x>EPA
United States      Industrial Environmental Research  EPA-600/7-78-158
Environmental Protection  Laboratory          August 1978
Agency        Research Triangle Park NC 2771 1
Sampling System
Evaluation for
High-temperature,
High-pressure
Processes

Interagency
Energy/Environment
R&D Program Report

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                RESEARCH REPORTING SERIES

Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:

      1.   Environmental Health Effects Research
      2.   Environmental Protection Technology
      3.   Ecological Research
      4.   Environmental Monitoring
      5,   Socioeconomic Environmental Studies
      6.   Scientific and Technical  Assessment Reports (STAR)
      7.   Interagency  Energy-Environment Research and  Development
      8.   "Special" Reports
      9.   Miscellaneous Reports

This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this  series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the  Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of  energy-related pollutants and their  health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
                           REVIEW NOTICE

 This report has been reviewed by the participating Federal Agencies, and approved
 for publication. Approval does not signify that the contents necessarily reflect the
 views and policies of the Government, nor does mention of trade names or commercial
 products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.

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                                         EPA-600/7-78-158
                                                August 1978
      Sampling System Evaluation
for  High-temperature,  High-pressure
                    Processes
                           by

         William Masters, Robert Larkin, Larry Cooper, and Craig Fong

           Acurex Corporation/Energy and Environmental Division
                      485 Clyde Avenue
                  Mountain View, California 94042
                    Contract No. 68-02-2153
                Program Element Nos. EHE623 and 624
               EPA Project Officer: William B. Kuykendal

              Industrial Environmental Research Laboratory
                Office of Energy, Minerals, and Industry
                  Research Triangle Park, NC 27711
                        Prepared for

              U.S. ENVIRONMENTAL PROTECTION AGENCY
                 Office of Research and Development
                     Washington, DC 20460

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                            TABLE OF CONTENTS



Section                                                                Page

  1.        INTRODUCTION 	        1

  2.        OVERVIEW OF RESULTS  	        3

           2.1  Phase I ~ Demonstration Tests  	        3
           2.2  Phase II — Condensation Tests  	        4

  3.        EQUIPMENT DESCRIPTION  	        7

           3.1  Sampling System  	   7

           3.1.1  Phase I ~ Demonstration Tests  	        7
           3.1.2  Phase II -- Condensation Tests	       44

           3.2  Exxon Miniplant Test Facility 	       53

  4.        TEST DESCRIPTION   	       60

           4.1  Phase I — Demonstration Tests	       60

           4.1.1  Procedures	       50
           4.1.2  Pretest Activities  	       51
           4.1.3  First Run	       61
           4.1.4  Second Run	       62
           4.1.5  Third Run	       62
           4.1.6  Post-Test Activities  	       63

           4.2  Phase II -- Condensation Tests	       63

           4.2.1  Procedures	       63
           4.2.2  Pretest Activities  	       63
           4.2.3  Runs 1 and 2	       64
           Runs 3 and 4	              65
           4.2.5  Post-Test Activities  	       65

  5.        DATA AND RESULTS	'	       66

           5.1  Phase I ~ Demonstration Test Data	       66
           5.1.1  Test Conditions	       66
           5.1.2  Instrument Readings	       66

           5.2  Phase I — Demonstration Test Results	       73
           5.3  Phase II ~ Condensation Test Data	       78

           5.3.1  Test Conditions	       78
           5.3.2  Instrument Readings 	       98

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                        TABLE  OF  CONTENTS  (Concluded)

Section                                                                 Page
           5.4   Phase  II  — Condensation  Test Results	       102
           5.4.1  General  Results  and Observations   	       104
           5.4.2  Initial  Analyses for Condensation  Effects  ...       Ill
           5.4.3  Alternate Approach  	       122
  6        CONCLUSIONS  	       126
           REFERENCES    	       128

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                           LIST OF ILLUSTRATIONS

Figure                                                                 Page
 3-1       High-temperature, high-pressure sampling system	     11
 3-2       System schematic 	     13
 3-3       Exploded view of HTHP probe	     15
 3-4       Aerotherm HTHP sampling probe and duct interface
           valve	     19
 3-5       Access valves	     21
 3-6       HTHP probe housing/side view	     23
 3-7       HTHP probe housing/end view	     24
 3-8       HTHP probe/side view/front half	     25
 3-9       HTHP probe/side view/back half	  .     27
 3-10      HTHP probe rear access plate and  controls/side
           and end view	     28
 3-11      HTHP probe rear access plate and  controls/top view ...     29
 3-12      Dowtherm system	     30
 3-13      Dowtherm console  	     31
 3-14      Gas sampler train - flow control  oven	     34
 3-15      Oven assembly	     35
 3-16      Organic cartridge	     37
 3-17      Organic module	     38
 3-18      Organic module  — exploded view	    39
 3-19      Flow control  oven and gas train	     41
 3-20      Organic module  and  impinger bottles	     43
 3-21      Control consoles  	     45
 3-22      Probe configurations  	     47
 3-23      Scalping cyclone  assembled 	     49

                                    vii

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                      LIST  OF ILLUSTRATIONS  (Continued)

Figure                                                                  Pa9e
 3-24      Scalping  cyclone disassembled	     50
 3-25      Transport tube	     52
 3-26      Pressurized fluidized bed coal combustor  system  ....     54
 3-27      HTHP probe assembly installed at Exxon  miniplant ....     57
 5-1       Probe inlet bias	     72
 5-2       Particle size distribution	     76
 5-3        Impactor substrates  	     79
 5-4        Impactor substrates  	     81
 5-5        Impactor substrate — Run 3, Stage 5	     83
 5-6        Impactor substrate — Run 2, Stage 5	     85
 5-7        Particle photomicrographs Stage  1  	     87
 5-8        Particle photomicrographs Stage  2  	     89
 5-9        Particle photomicrographs Stage  4  	     91
 5-10      Particle photomicrographs Stage  6  	     93
 5-11      Particle chemical composition  	     95
 5-12      Condensation of  H2S04	    101
 5-13      Particle Photomicrographs -- Run 1, front filter ....    107
 5-14      Particle photomicrographs -- Run 4, front filter ....    109
 5-15      Particle photomicrographs -- Run 4, rear filter  ....    113
 5-16      Particle photomicrographs — Run 1, rear filter  ....    115
 5-17      Particle chemical composition — blank rear filter ...    117
 5-18      Particle chemical composition -- Run 4	   119
                                     vm

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LIST OF TABLES
Table
3-1
3-2
5-1
5-2
5-3
5-4
5-5
5-6
5-7
5-8
5-9
5-10
5-11
5-12
5-13

5-14


Sampling System Capabilities 	
Utility Requirements 	
Test Conditions 	
Phase I Probe Instrumentation Readings 	
Gas Train Instrument Readings 	
Anisokinetic Correction Factors — Phase I 	
Structure Temperatures 	
Parti cul ate Content 	
Particle Size Distribution 	
Exxon ~ Phase II FBC Operating Conditions 	
Probe Instrumentation Readings 	
Anisokinetic Correction Factors ~ Phase II 	
Particulate Concentration 	
Visual Observation of Filters — Phase II 	
Concentration of Elements in Flyash SSMS 	
Analysis (Partial) 	
Partial Comparison of Front and Rear Particulate ....
Catches from Exxon Test Series I and II 	
Page
9
59
67
68
69
70
74
75
77
97
99
103
105
106

123

124
     IX

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                                SECTION 1
                               INTRODUCTION

       Advanced coal  conversion processes  present new problems in parti -
culate sampling, including severe environments beyond the capabilities of
conventional equipment.
       Fluidized bed  combustion and coal gasification processes emit
gases containing large quantities of fine  particles.  These particles
must be removed to prevent damage to process equipment (mainly turbines)
and to eliminate potential environmental pollution.  Development of par-
ticulate removal equipment is an important step toward making advanced
coal conversion processes practical.  The sampling system described in
this report is  one of the first tools available for measuring the collec-
tion efficiency of fine particle removal devices operating in high-
pressure, high-temperature environments.  The  sampling system described
in this report  is specifically  designed for  the high  temperatures and
pressures found in pressurized  fluidized bed combustors  (PFBC).  The
system uses  an  extractive sampling  approach,  withdrawing  samples from  the
process stream  for complete  analysis of particulate  concentration,  shape,
size,  and chemical composition.  The capabilities  of  the  new  system have
been  demonstrated in  two  phases of  sampling  operations at Exxon
Corporations pilot-scale pressurized,  fluidized bed  combustion Miniplant
located in  Linden, New Jersey.  The first  phase of testing was performed

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during the week of March  21,  1977 with the sample probe in its basic
configuration.  The second  test phase used modified probe internals
designed to  investigate possible condensation of alkali metals as a
result of cooling the  sample  prior to collection.  These tests were
performed the week of  May 23,  1977.  The system performed successfully in
a variety of operating modes,  producing sample data from both test series.
       Acurex has developed the HTHP sampling system for the Industrial
Environmental Research Laboratory of the U.S. Environmental Protection
Agency.  This work  is  part  of the program, Measurements of
High-Temperature, High-Pressure Processes (Contract 68-02-2153), intended
to produce the new  sampling technology needed for advanced coal
conversion processes.  The  EPA project officer was William B. Kuykendal.
       An overview of  the results of both sampling operations is
presented in Section 2.   Section 3 discusses the sampling system
equipment in detail and gives a brief description of the Exxon Miniplant
test facility.  Section 4 describes assembly and operating procedures and
contains a narrative of events in each phase of tests.  All results and
supporting data are presented in Section 5 while Section 6 summarizes the
program conclusions.

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                                SECTION 2
                           OVERVIEW OF RESULTS

       This Section presents an overview of the results from both series
of sampling operations,  including the Phase I demonstration tests and the
Phase II condensation tests.  A more thorough discussion of the results
can be found in Section  5.
2.1    PHASE I — DEMONSTRATION TESTS
       The objective of the first sampling operation was to demonstrate
the HTHP sampling system's range of capabilities.  Three sampling runs
were successfully made:   one using a filter* to collect total
particulate, and two using  a cascade impactor to collect particle sizing
data.  Trace metals  and trace  organics  sampling equipment was operated
during the filter run.  The tests produced the following data:
       •   Particulate concentration
       •   Particulate size distribution
       t   Moisture  content
       •   Particulate chemical composition
       •   Particulate shape
 *A complete detailed description of the  sampling equipment'is  given  in
  Section 3.

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       •   Duct gas temperature  and pressure
       •   Access port  and  valve external  surface temperatures
The test also produced  samples of trace organics collected on XAD-2
porous polymer sorbent  and  trace elements  collected in oxidizing impinger
solutions.  However, the  analysis of  these samples is beyond the scope of
the HTHP program.
       The test series  demonstrated the capability of the sampling system
to operate in a severe  PFBC environment of 740°C (1360°F) and 910 kPa
(9 atm).  Generally, the  system  operated as designed with regard to:
obtaining access to the pressurized duct while the process was operating,
inserting the sampling  probe,  sampling the gas stream, and withdrawing
the sampling probe.  However,  as might be  expected in a first field test
demonstration, a few hardware  problems were found.  Most of these were
corrected before the sampling  tests,  but one uncorrected problem, a
malfunctioning impactor heater,  gave  sample collection temperatures which
were  lower than desired.  The  heater  was replaced for the second phase of
testing.
       During the test  sequence, the  sampling operations proceeded very
smoothly.  The three sampling  runs were completed within a 30-hour period
(20 working hours).  The  tests showed the  versatility of the system,
operating with two different types of particle collectors, with and
without trace element sampling equipment.
2.2    PHASE II — CONDENSATION  TESTS
       The goal of Phase  II was  to determine the effect of sample cooling
on measured particlate  mass and  composition.  We were particularly
concerned that trace elements might condense in the probe in significant
quantities between process  temperature and 450°F.  The condensation

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effects tests were also successfully performed.  A total of four separate
runs were completed with the cyclone-dual filter configuration.  The only
difference between the runs was the sampling time of each, and, in the
case of test number three and four, two Saffil alumina filters were
"sandwiched" to comprise the front filter (at stream conditions).  Tests
1 and 2 used a single front filter.  All other conditions, both in the
FBC system and in the sampling system remained, nominally, the same.
Trace element and trace organic sampling equipment were not employed in
the Phase II tests.
       Again, as in the first test series at the Miniplant, certain
hardware problems prevented some measurements, the most important of
which, was the malfunctioning of the stack thermocouple.  This
temperature  is approximated at 730°C (1350°F), the average stack
temperature  during the  first  test  series.  Very  similar PFBC  system
operating conditions  between  the two test series make this a  reasonable
approximation.   Another less  critical malfunction occurred in the
transport tube outlet filter  thermocouple.   This problem  was  an
intermittent electrical  short.  Consequently,  the measurement could  be
made  only periodically.   Another problem occurred with  the scalping
cyclone.  Its protective gold plating blistered  and  peeled causing  gold
contamination  in the  cyclone  and front  filter  catches.  The  resultant
oxidation of the titanium cyclone  body  did not  appear  to  contribute  to
the contamination  problem.
       As previously  mentioned, the purpose  of the  Phase  II  tests  was  to
investigate  the  effect of sample cooling on  measured particulate mass  and
composition. Based on one test at one  set of  PFBC  operating  conditions,
the Phase  II tests showed no  apparent  indication of  trace element

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condensation at the  reduced  sample  collection  temperature.  In other
terms, we can  say  that  sample  cooling  seems  to have had little effect on
measured particulate mass  and  composition.

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                                SECTION 3
                          EQUIPMENT DESCRIPTION

       The following  discussion is divided into two parts:  (1) a
description of the advanced sampling system,  this section being further
divided to discuss the original probe configuration and the modified
configuration for the condensation effects tests, and (2) a description
of the PFBC Miniplant test facility.
3.1    SAMPLING SYSTEM
       The sampling system described in  this report samples particulate,
trace organics and trace metal contaminants  in high-pressure, high-
temperature gas streams.  The  system represents  an advancement  in the
state of the  art  designed to sample new  coal conversion processes.  This
section is divided into a discussion of  the  sampling  as  it was  used both
in Phase  I and Phase  II tests.  Since  there  were many similarities
between the two systems, such  as  the pressure  containment  vessel  and
traversing mechanism, only the differences between the two probe
configurations will be mentioned  in Section  3.1.2.
3.1.1  Phase  I -- Demonstration Tests
       The basic  functions of  the  sampling system  are to:
       •   Safely contain facility pressure
       •   Insert the sample probe into  the  process  duct  while  the
           process is operating
       •   Extract a  representative sample

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       •   Cool the  sample  to  a temperature which  is compatible with
           developed particle  collectors yet prevents condensation
           (230°C)
       t   Collect  and  aerodynamically  size particulates
       •   Collect  trace organics  and trace metals
       •   Monitor  duct conditions  and  control sample flowrate to give
           accurate  isokinetic capture  conditions
       •   Remove the sample probe  and  close off duct access  so that
           collected samples may be removed while the process remains
           pressurized
       To  perform these functions,  the  sampling system  includes the
following  subsystems:
       •   Sample probe assembly
       t   Dowtherm coolant system
       •   Hydraulics for probe traverse actuation
       •   Flow control oven
       •   Trace organics module
       •   Trace metal  impinger train
       •   Control  consoles
       System  capabilities  are described in Table 3-1.  Figures 3-1 and
3-2 show system schematics  of  the  HTHP  sampler.
3.1.1.1  Probe Assembly
       The probe assembly includes  the  sample  probe, probe housings, and
duct access  valves.   The sample probe itself,  shown  in  Figure 3-3, con-
sists of the sample  nozzle,  pitot  tube, Dowtherm-cooled section with man-
ifold, a sample particulate collection  device, a flowmeter, a heated
transport tube section,  transducer  and  control devices  mounted on the

                                     8

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                  TABLE  3-1.   SAMPLING SYSTEM CAPABILITIES
Sample Environment

    t   Temperature

    •   Pressure
        Gas  Constituency
            CO
            C02
            NO
            S02
            H20
            NOX
            H2S
            trace orgam'cs
            trace inorganics

        Stream Velocity

        Particulate Grain Loadings
    •   Particulate Size Range
        (for classification)
     •    Duct  Size
 Sampling  System  Configuration
 Traverse  Capability or Penetration
 of Nozzle into  Duct or Vessel
650°C - 1000°C (1200°F - 1800°F)

300 - 2000 kPa (3 - 20 atm)

Concentrations subject to further
investigation, dependent on process
sampled
2-46 m/s (8 - 150 fps)

0 - 34.3 g/m3 (0-15 gr/ft3)
(subject to further consideration
and actual process characteristics)

0.2-26 microns (Notes:  Larger
particulates may be acceptable in
most cases of total mass determination.
or if classified, they may be amenable
to "scalping" ahead of classification
device)

Variable depending on probe; std.
is 20.3 cm (8 in.) I.D. minimum

Modular, so as to allow in-situ or
extractive sampling by cooled probe

Approximately 46 cm (18 in.) either
in-situ or extractive configuration
(some dependence on internal config-
uration of duct or vessel).  Can be
extended by relatively minor hardware
modification (longer probe, chamber
extension, spool piece, etc.)

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                            TABLE 3-1.   (Concluded)
Access  Process Port Requirements
Stream Constituency Analysis
Standard:  10.2 cm (4 In.) IPS
minimum, 136 kg (300 lb.) flange
access through 10.2 cm (4 In.)
IPS alloy gate value (Note:
Smaller ports may be acceptable
If special probe assembly is used)

Particulates, gases (inorganic and
organic, trace elements,  trace
organics)
                                      10

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                                                                         S-038b
Probe Drive
Hydraulic Cylinder
               Microswitches For
               Transverse Control
                          Inner Tubular Housing
              Hydraulic Lines
            Control Umbilical
                                                     Dowtherm Coolant
                                                   Systems And Controls
                                                         JL
Outer Tubular
Housing
Dowtherm Coolant
Supply And Return

=_^_^._=_=^===,-^-^  /
                                               Sample Line
             B T) H a
             a 3 ra§
             3* ® -s S
             •aa* Hts'4
             -»' A IV
                           Hydraulic
                                          Control Valve
                                          And  Operator
            Control Console    Supply System

                     Figure 3-1. High-temperature, high-pressure sampling system.
                                                                  ACUREX

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                                                                           i
Flow
              Process Duct
             Access Valves
                          Enclosure
                          (Pressure Boundary)
     s


KNKNL/
                                                      Control Valves
                                                             Flexible Line
                                                              Heat Tracing
                                                                           Vent
                                       Flow        Organic
                                     Controls     Collector

                           Figure 3-2.  System schematic.
                                                           Trace
                                                           Metals
                                                         Impingers

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        Transducers
        &  controls
Impactor
stacks
Heated
transport
tube
                                                                   5
                                                                   i
                               Nozzles


                         Figure 3-3.
                Exploded view of HTHP probe.
                                                       Pi tot
                                                       tube
                              15

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end of the probe.  All probe components, internal and external, that
would be exposed to temperatures in excess of 1000°F, were constructed
of 625 Inconel.  These include the probe tip, nozzle, cooling section,
and transport tube up to the cascade impactor.  Most other probe
components were constructed of grade 316 stainless steel.  The assembled
sample probe is then installed in an inner probe housing.  The inner
probe housing is a tube that telescopes into  an outer probe  housing and
is sealed by a bolted flange and sliding seal.  The outer probe housing,
on its laboratory support stand designed to a factor of safety of 4.0,  is
shown in Figure 3-4.  The outer probe housing is bolted to the process
duct by two 10.2 cm (4-in) diameter gate valves in series.   This 10.2 cm
(4-in) opening provides clearance for the sample probe to be inserted
into the sample stream, as shown in Figure 3-5.  The entire  telescoping
system, shown in Figures 3-6 and 3-7, is driven by hydraulic cylinders.
       Two types of sample particulate  collection devices were used in
the demonstration tests.  They were a University of Washington Mark III
cascade impactor with seven stages of particulate sizing  and a glass
fiber thimble filter with a large total mass  capacity but with no sizing
capability.
       The inlet nozzle is interchangeable to allow isokinetic sampling.
The nozzle diameter used was 1.9 cm (0.75 in) for all tests  and was sized
according to the anticipated Exxon miniplant  stream conditions.  The
actual stream velocity (a calculated, not measured value) was not as
close to expected conditions as would be desirable.  A discussion of
isokinetic sampling rates is in Section 5.
                                    17

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                       Figure 3-4.
Aerotherm HTHP sampling probe and duct interface valve.

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I- •
                                                                                                              eo
                                                                                                              in
                                                                                                              o
                                                     Figure 3-5.

                                                     Access valves.

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ro
CO
                                                                                                SEE SEPARATE PARTS LIST PL 7123-053
                                                                                                                          1    23
                                         Figure  3-6.   HTHP probe housing/side view.

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Figure 3-7.   HTHP probe housing/end view.

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ro
en
                              Figure  3-8.   HTHP probe/side view/front half.

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       Sample gas enters the inlet nozzle isokinetically  and  travels
through the Dowtherm-cooled section, shown in Figure 3-8.  The  sample  gas
then passes through one of the particulate collection devices mentioned
above.  It then goes to a flowmeter and an electrically heated  and
controlled transport tube section which is mounted to and  routed  through
a rear access plate.  Process pressure, velocity pressure, orifice
differential pressure, and sample gas temperature instrumentation lines,
lead aft to the access plate, as shown in Figures 3-8 and  3-9.
Thermocouples, pressure transducers, control valves, and  Dowtherm
manifolds are mounted behind the rear access plate (Figures 3-10  and
3-11).  After cooling, the sample gas, now at 232°C (450°F),  is
transported through a heat-traced line to the flow control oven.
3.1.1.2  Dowtherm Coolant System
       The sample conditioning heater/cooler in the front  probe assembly
receives working fluid from the Dowtherm system, shown in  Figures 3-12
and 3-13.  This system maintains the Dowtherm temperature  at  about
232°C (450°F).  The system consists of a pump, heater, heat
exchanger, flowmeter, transfer lines, and a primary receiver/deareator
tank with a Dowtherm surge/supply tank and an air receiver tank.
Dowtherm can be quickly heated or cooled by selected valving
arrangements.  The pressure can be controlled to raise the boiling
point.  Heat flux can be controlled with a flowmeter.  The self-contained
unit also has mechanical instrumentation for flowrate, system pressure,
temperature, and fluid level for process monitoring.
3.1.1.3  Hydraulics
       Probe  insertion, extraction,  and precise positioning  is
 accomplished  by hydraulic  cylinders.  These drive the telescoping probe

                                     26

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                           M M  "-ACCEPTABLE ROUTING
                      SELTION ?i-n   LOCATION FOR HEATER
 2 PLACED ACCEPTABLE ROUTING
     " LOCATION FOR THERMOCOUPLE
               , REF
Figure  3-9.    HTHP probe/side view/back  half.

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                                                                           D 50726  7123-053   A
Figure 3-10.   HTHP  probe rear access  plate and controls/side and end view.

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                                                                             SEE SHEET I FOR REVISIONS
                                    36) LOCATE AT ASSf
                                                                                  50726
                                                                                        7l23r053
Figure 3-11.   HTHP  probe  rear access plate and  controls/top view.

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GO
o
                                                                                                                    aur
                                                                                                                  outlet
                                                                                                                  temperature
                                                                                          OmercutUi
                                                                                          pressure gtuge
                                                                                                   System outlet
                                                                                                    temp
            Fran HTHP
            probe
            outlet
Heat
exchanger
                                                     Figure  3-12.   Dowtherm system.

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Figure 3-13.  Dowtherm console.
              31

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housing, which, in turn, is driven by a hydraulic pump powered by an
electric motor.  Solenoid valves plumbed in line with the hydraulic
supply lines are used to control the hydraulic cylinders.  These operate
by remote switches on the probe control console.  Fail-safe devices .have
also been incorporated to avoid inadvertantly traversing the probe.
Probe positioning in the process duct can be automatically repeated by
setting cams prior to testing.
3.1.1.4  Flow Control Oven
       Sample gas at duct pressure exits the throttling valve of the
probe and enters the flow control oven.  This oven contains a back
pressure regulator to reduce sample gas pressure to 172 kPa (25 psig),  an
adjustable-choked orifice for flow measurement, a heater, and a flow
control valve, as shown in Figures 3-14 and 3-15.  Excess sample gas  is
vented to the atmosphere.  The balance  is routed to the impingers and
organic train at a known pressure, flowrate, and temperature.  The oven
was run at 232°C (450°F) for this series of tests to  avoid
condensation of selected sample gas constituents.  Controls and
instrumentation are remotely mounted in the gas train control console
which is connected by an umbilical cord containing the  various pressure,
power, and temperature lines.
3.1.1.5  Organic Module
       An organic module was used to collect trace organic gas
constituents.  It cools the sample gas  to 20°C  (68°F) and collects
organic vapors in a porous polymer granular sorbent bed.  Rohm-Haas XAD-2
chromatographic packing material -- chemically  cleaned  prior  to testing
~ was the sorbent used.  Cooling and conditioning is accomplished by a
single and double concentric shell heat exchanger, and  by water

                                    33

-------
                         To
                                        Back pressure relief
                                                                        To ATM
To organic tr«1n
•nd linger bottles
                                                                           Over prtisure
                                                                           rupture disk
                                                                                             Insulated httt
                                                                                             traced staple
                                                                                             line
                                                                                                                   Gas saeple
                                                                                                                   fran HTHP
                                                                                                                   probe
Indicating heat
trace temperature
controller
                                                                                                               Differential
                                                                                                               pressure
                                                                                                               gauge
                                                                                                     .r*in          w^
                                                                                                     control console I
                               Figure  3-14.   Gas  sampler train  —flow control  oven.

-------
CO
en
                                                                                                                                          3,4,. ,/2,QDX .04-9
                                                                                                                                  MA_E CDsJKtECLTCR
                                                                                                                                      CONNE.CToa
                                                                                                                                  STA^4DARD CVCLQNJE, CVEN t
                                                                                                                         "'° ^ff ^


                                                                                                                         '"'." -' '".- .-L5S1JS
                                                                                                                                       &CUREX
                                                                                                                                      ' Aerolhem
                                                                                                                                     D  50726   7237-OOe
                                                              Figure  3-15.    Oven  assembly.

-------
circulating through the impinger ice bath.  The water is either heated or
cooled automatically to the preset system temperature.  Condensation is
expected to occur and a valve is available for decanting the sample.
This unit is identical to that used in the Acurex commercially available
Source Assessment Sampling System.  The organic cartridge and the organic
module assembly are shown in Figures 3-16, 3-17, and 3-18 respectively.
3.1.1.6  Trace Metal Collectors
       A train with three high-volume glass impingers followed by a
silica gel dryer was used to collect trace metals.  The impingers were
charged with the following oxidizing reagents as prescribed by the
IERL-RTP Procedures Level 1 Environmental Assessment Manual (Reference 1)

            Impinger                     Solution
             No. 1           6M - H202
             No. 2           0.2 M (NH4)2 S208 + 0.02 M AgN03
             No. 3           0.2 M (NH4)2 S208 + 0.02 M AgN03
             No. 4           Indicating Type Silica Gel
Figure 3-19 is  a photograph of the trace element  impingers  along with  the
organic module  and  flow  control oven as they appear assembled for a  test
run.  Figure 3-20 shows  a  schematic of the organic module  and  impinger
bottle assembly.
3.1.1.7   Controls
       The  sampling system includes instruments  for measuring
temperatures  and pressures in  the process  duct,  the gas sample,  system
heaters  and coolant.   The  system  has  controls  for sample  flowrate,
 traverse drive, heaters, coolant  pump and  purge gas.   Sample  flowrate  was
 controlled by a motor-actuated valve  located at the  probe exit.   A

                                     36

-------
                              80 MESH 316SS
                                    UPPER CRIMP RING
                                    AND SEALING FLANGE
                                     316SS TUBE
                                     LOWER CRIMP RING
Figure 3-16.  Organic  cartridge.

-------
oo
CXI
        Return Flow
         Impinger Bath
    Cold Water From
      Impinger Bath


         Hot Gas	
      From Oven
      Liquid Passage

           Gas Passage

         Gas Cooler
    Organic Cartridge


         Condensate
            Reservoir
             Section
3-Way Solenoid Valve

      To Heat Exchanger
      In Impinger Case

    From Heat Exchanger
    In Impfnger Case
      Cooling Fluid
      Reservoir
                                                                Immersion
                                                                Heater
                                                           Liquid Pump
   Temperature
   Controller
                                Figure 3-17.  Organic module.

-------
Ice Water In
Hot Gas In
                      I   I
Ice Water Return
Gas Cooler
Inner Wall

Coolant Fluid Out
                                    Coolant Fluid  In



                                    Organic Cartridge


                                    • Case


                                    Cool Gas  Out

                                    Condensate Out
        Figure 3-18.  Organic module —exploded view.
                         39

-------
  Flow
Control
 Oven
                                        rganic
                                         odule
                       Figure 3-19.  Flow control oven and gas train.

-------
              From gas sample
              train-flow control
                           Primary concentric
                           double-shell heat
                           exchanger
                  Secondary
                  concentric
                  single shell
                  heat exchanger
CO
                                                                      3-way
                                                                      solenoid
                                                                      valve
                                                                             Hater cooling lines

1
.
>
>
>
r
t
Imners
heater

7
Ion
In
te
CO


dlcatlng
mperature
ntrol ler
<^>
Accumulating
(cooling
reservoir)
                                                                               To ATM
                                                                               0
                                                                                    s
                                                                                    •S
                                                                                    Cr
                                                                                                                                   Bottle No.  4
                                                                                                                                   silica gel
                                                                                                          Bottle No, 1  t No. 2
                                                                                                          silver nitrate &
                                                                                                          ammonium  persutfate
                                                                                                                             Bottle
                                                                                                                             silica
                                                                      No.
                                                                      gel
3  \  ^F
                                                                                                   Ice bath
                                                                                                   coolant
                                                                                                   pump
                                              Figure  3-20.   Organic module  and  impinger  bottles.

-------
redundant  manual  valve preceeded the automatic valve for safety
purposes.   The  probe  traverse  drive was hydraulically actuated from a
control  console.   All  heaters  were thermoscatically controlled.  The
coolant  pump  was  manually operated by a switch located on the Dowtherm
console.   The nitrogen purge gas was supplied by Exxon and controlled by
a single stage  regulator mounted adjacent to the probe housing.  Most of
the  instrument  readouts and controls are housed in the two portable
control  consoles, shown in Figure 3-21.  Control, power and instrument
connections are made  by multi-pin connectors and umbilical cords.
3.1.2  Phase  II — Condensation Tests
       Following  the  system demonstration tests, a second series of sam-
pling operations  was  conducted at the Exxon Miniplant.  The purpose of
these tests was to investigate the effect of sample cooling on measured
particulate mass  and  composition.  There was specific concern that trace
elements in vapor form might condense to the solid state between process
temperature and pressure conditions and the particulate collection
temperature and pressure.
       Of  particular  interest  to process developers are the more common
corrosive  alkali  metals, sodium and potassium.  For these tests, the
sampler  was configured to collect particulate at process temperature (see
Figure 3-22), so  trace element condensation occurring within the sampling
system could  be investigated.  First, particulate would be filtered at
process  conditions, then the sample could be cooled and filtered to
collect  condensation  products. The trace element concentrations could be
analyzed and  compared for significant differences between the hot and
cold filters.
                                     44

-------
en
                                           Figure  3-21.   Control  consoles,
                                                        Control consoles.

-------
Normal


Cooler


Impactor
       Process Flow


Condensation Test

  Scalping   732° C
  Cyclone   Filter
                                                       Sample Flow
       Process Flow
                                    (Or Filter)  Throttling
                                                 Valve


                                             Control
                                             Valve
                                  Choked
                                  Orifices
I
1


Cooler
^

!
(400°F)
 Filter
                       Figure 3-22.  Probe configurations.

-------
       The  individual components of this  sampling  train,  where different
 from  the standard configuration, are discussed  in  the  following
 sections.   It should be noted that since  this test  series was  to study
 condensation phenomena only, no provisions for  sampling  trace  organics or
 trace elements by the impinger method were included.   After  final
 filtering through the cold filter,  the sample gas was  simply vented  to
 the atmosphere.
 3.1.2.1    Scalping Cyclone
       The cyclone (shown in Figure 3-23  and 3-24)  at  the front of the
 probe was designed and fabricated by Southern Research Institute to
 operate at stream ccnditions.   It was made of 6AL-4V titanium  alloy  with
 a 26-ym thick gold plate for corrosion resistance.  Because  of the high
 temperature, it was designed with flat faced flanges and  bolted with ti-
 tanium nuts and bolts.
       The cyclone's nominal D5Q cutpoint is 0.3 urn (aerodynamic
 diameter) at 4.38 x 10"5 m3/sec (1.01CFM)  at standard  temperature  and
 pressure.  SRI was unable to predict the DSQ cutpoint  at  stream
 temperature and pressure.
3.1.2.2    Front-End Filter (Saffil Alumina)
       The front end filter element is made from Saffil alumina fiber
matt.   Saffil  alumina is a ceramic  fiber material that Acurex  is
 currently testing for high-temperature baghouse filters.   This material
 seems  to offer excellent temperature resistance and effective  filtration,
 but its performance has not yet been fully characterized.  Its
 performance in the condensation tests (Phase II) was quite good,
 particularly with a two-filter "sandwich".  The filter matt  is sandwiched
 between two 47-mm 316 SST screens stitched together with  316 SST wire.

                                    48

-------
Figure 3-23.  Scalping cyclone assembled.

-------
  T
1.905 cm
(0.7
75 in
       0.508 cm
       (0.2 in)
                                                 0:836  cm
                                                 (0.329 in)
                                       1.524  cm
                                       (0.6 in)
                              0.9525 cm
                              (3/8  in)
    Figure  3-24.  Scalping cyclone disassembled.
                       50

-------
The filter housing is made from 316 SST and uses flat face bolted flanges
for sealing.
3.1.2.3    Sample Conditioning
       The primary requirement of the sample conditioning system is to
reduce the temperature and pressure to 204°C (400°F) and 101 kPa
(1 atm).  A further requirement of the system is to not let the
temperature drop significantly below 204°C (400°F).
       To accomplish this, the sample undergoes the following process:
       •   Cooling from stream conditions to 232°C (450°F) in the
           existing Dowtherm cooling section
       •   Transport through a bypass sleeve in the impactor housing
           section because it is important to keep the velocity high to
           keep any condensates from settling
       •   Reheat to approximately 300°C  (570°F).  This is necessary
           because sonic throttling (done in the next section) will cool
           the gas about 80°C (170°F) at  the throat (the temperature
           will then recover back to 300°C (510°F)).  Heating is done
           by running the gas through an  annular passage past electrical
           heaters, as shown in Figure 3-25.  The  gas is passed through
           the annular passage because a  high velocity  is required to  get
           the necessary heat transfer coefficient.
       •   Pressure drop from stream pressure to ambient occurs through
           three critical orifices.  This is done  to avoid supersonic
           conditions downstream of each  throat and hence very large
           local temperature drops.  The  orifices  were  sized such that
           the velocity downstream of each throat  was slightly supersonic
           at the design flowrate.

                                    51

-------
                     xxx x x x x" x x" x*
tn
ro
                          Flow measurement
                               orifice
                                                                                 Sonic orifices
                                          Figure 3-25.   Transport tube.

-------
       •   Cooling from 300°C (570°F) to 204°C (400°C).  This is
           done between the exit of the probe and the rear-end filter
           housing through natural air convection.  The tube is heat
           traced to give a final temperature control.
3.1.2.4    Final Filter Gelman Micro-Quartz Glass Fiber
       The final cleanup filter was a 47-mm Gelman microquartz glass
fiber filter.   It has a minimum 99.9-percent retention of 0.3 m
particles.  It was selected because of its low trace metal content.
3.2    EXXON MINIPLANT TEST FACILITY
       This section describes the Exxon Miniplant facility itself and the
deployment of the sampling system in the facility during both series of
sampling operations.
       The Miniplant is a pilot-scale pressurized, fluidized bed
combustor operated by the Exxon Research and Engineering Company at
Linden, New Jersey.  The PFBC process is being developed as  a more
efficient and cleaner method of burning coal.  A  sketch of a typical PFBC
system is shown in Figure 3-26.  Coal, along with limestone  or  dolomite,
which act as SO^ sorbents, is injected into the bottom of the
pressurized boiler.  Coal is burned  in the  limestone  bed which  is
fluidized by the incoming combustion  air.   Sulphur dioxide formed  in the
combustion process is removed by the  limestone bed.   Steam coils immersed
in the fluidized bed remove some of  the heat of combustion and  maintain
the bed temperature in the range of  816°C  (1500°F) to 927°C
(1700°F).  Steam thus generated operates a  steam  turbine.  The
desulphurized flue gas passes through a particulate removal  system  and  is
then expanded across a gas turbine.   The particulate  removal system must
reduce the particulate loading down  to levels sufficiently low  to protect
                                     53

-------
           Gas turbine
                     Sampling  location

                         Separator
Jl
               Coal  and'
               make-up
               sorbent
                                            Air
                                         compressor
                             Boiler
                                               Solids
                                              transfer
                                               system
                         £
                         X.
                         r
                          To sulfur
                          recovery
                                                                    I Separator

                                                                 I
                  fl
                                                                Discard
                                                       Regenerator
Figure 3-26.   Pressurized fluidlzed bed coal combustor system.
                                 54

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the gas turbine and meet current pollutant emission standards.  The
Miniplant facility does not presently include a final gas cleanup device
or turbines.
       The Miniplant facility consists of the combustor tower and control
building.  The combustor is a four-story structure, with platforms at
each level.  Stairways connect the platforms.  A crane on the top level
is available for moving large equipment.  The control building includes a
laboratory area.
       For both test phases, the sampling location was downstream of the
secondary cyclone (particulate removal device), as indicated in Figure
3-26.  At this location, there is a specially constructed duct section
with a sampling port.  The sampling port has a 10.2-cm (4-inch) 136-Kg
(300-pound) pipe flange which interfaces with the sampling  system access
valves.  The duct diameter at the sampling  location  is 25.4 cm (10
inches).
       The sampling location was physically located  at the  top of the
combustor tower.  When installed, the probe assembly was horizontal,
about 1.22 m (4 feet) above the platform  (see Figure 3-27). The coolant,
console  and hydraulic pump were also placed on the top platform, near the
probe assembly.  The control consoles and gas train  equipment were set  up
one floor below, where a partial enclosure  gave  some weather protection.
       The route between the laboratory area and the sampling location
included four flights of stairs and about a 30.5 m  (100-feet) walk.  The
sample probe assembly was hand-carried along this route  before and after
each sampling run.  Probe cleaning, assembly, disassembly  and sample
removal  were all done in the laboratory.  The lab facility had an
analytical balance, oven, desiccator and  other equipment used in sampler
                                    55

-------
          Figure  3-27
     HTHP probe assembly
installed at Exxon miniplant.

-------
preparation and sample processing.   Labware and materials  were  supplied
by Acurex.
       The Exxon facility provided  a number of utilities supporting the
sampler operation.   Power connections, water,  and nitrogen supplies are
summarized in Table 3-2.   In addition, Exxon supplied technician support
during equipment setup and disassembly.

                     TABLE 3-2.  UTILITY REQUIREMENTS
      Electrical:
         480 VAC, 3 phase, 40 amp
         115 VAC, 15 amp
      Water:
         18.9 L/min (5 gpm), 34.47  kPa  (50 psi)
      Pure Nitrogen:
         (flow and pressure  required depending on  stream
          conditions)
         •   For this test,  about 8.76  x lO"1*  Nm3/sec.
             (2 scfm) at 861.8  kPa  (125 psi)
1 line
6 lines
1 line
1 line
                                   59

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                                SECTION 4
                             TEST DESCRIPTION

       This section describes assembly and operating procedures for  the
sampling equipment and some of the significant events which occurred
during the two test phases.  The narrative of events in each phase  is
divided into four sections:  procedures,  pretest activities, sampling
runs, and post-test activities.
4.1    PHASE I -- DEMONSTRATION TESTS
4.1.1  Procedures
       Equipment setup and operation was  done according to a formal
procedure which defined proper installation of access valves and probe
housing, probe setup and assembly, system preparations for testing,  test
sequence, shutdown and sample removal.
       In several cases, decisions were made in the field to change
predefined procedures.  For example, the  exposure and limited space  on
the sampling platform made impactor removal at the sampling location
impractical.  The entire probe was carried to the lab for disassembly.
       In precleaning the sampling equipment, the procedures in the
IERL-RTP Procedures Manual for Level 1 Environmental Assessment were
followed with one exception;  the nitric acid passivation of some internal
surfaces of the probe, organic module and flow control oven was omitted
                                    60

-------
because large acid containers were not available.  Sample  removal  and
post-test cleaning also followed Level 1 procedures.
4.1.2  Pretest Activities
       Pretest activities included planned unpacking, setup  and  checkout,
plus fixing several problems with the facility  and sampling  system.  The
test preparations were completed between March  22 and March  30.
Heavy equipment was installed with the help of  Exxon personnel.   For the
nitrogen purge gas, Exxon provided a connection to the  facility  nitrogen
supply.  Exxon also assisted in making a support for the  cantilevered
probe housing.
4.1.3  First Run
       For the first test run, the sampling  system was  set up  using  the
thimble filter particulate collector  and gas  train equipment for the
purposes of obtaining grain  loadings.  Following preheating, the duct
access valves were opened and the sampling probe inserted into the duct
stream.  The sample flow control valve was opened  until the flow orifice
indicated a sample flow of 0.75  acfm  at  nominal particulate collector
conditions.  When flow conditions were established,  the gas train flow
control valve was opened, diverting  total  sample flow  through  the organic
module and impinger train.   Sampling  continued  for  30  minutes.
Instrument readings during the test  run  are  listed  in  Table 5-2.  At the
end  of the test run, the motor driven  sample flow  valve was left open  and
the  sample flow was shut off using the manual ball  valve.  The probe was
then withdrawn and gate valves were  closed.   After  cooldown, the probe
assembly was removed.  The probe  and  gas  train  were  taken to the lab area
for  sample recovery and cleaning.
                                     61

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4.1.4  Second Run
       For the second test run, the cascade impactor was  used  for
participate collection.  Since this was to be a very short  test  with a
small amount of gas sample collected, the gas train equipment  was  not
used.  Based on estimated particle concentration and impactor  capacity,
the maximum sampling duration was estimated to be between 30 seconds and
1 minute.  For this test run, 30 seconds was chosen.  To  achieve proper
sample flow as soon as possible, the motor driven control valve  was  left
at the same setting as the earlier filter run, and on-off control
accomplished with the manual  ball  valve.  As soon as the  probe reached
the in-stream position, the sample flow was started.  No  attempt was made
to adjust flow while sampling.   After 30 seconds, sample  flow  was  stopped
with the ball valve, the probe  was withdrawn and access valves closed.
After cooldown and probe removal,  the probe assembly was  carried as
carefully as possible down the  combustor tower stairs to  the lab.  There,
the impactor assembly was removed, disassembled and inspected.   The
amount and patterns of the catch seemed to indicate normal  operation of
the device (see Figures 5-3).  However, on one stage (Stage 4) the
substrate shifted slightly, and on another (Stage 7} some of the jets
were plugged.  After sample removal and cleaning, the probe was  ready to
be set up for the third and final  test run.
4.1.5  Third Run
       The third test run also  used the impactor for particulate
collection and omitted the gas  train equipment.  Based on the  lightly
loaded appearance of the 30-second impactor catch from Run  No. 2,  the
duration of this run was increased to 1 minute.  The flow control  method
for this run was identical to Run No. 2.  The manual valve  was again used

                                    62

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to start and stop sample flow with no attempt to adjust flowrate during
sampling.   Again the probe was taken to the lab for disassembly and
sample removal.  The impactor substrates were noticeably more heavily
loaded than for the 30-second impactor run (see Figures 5-3 and 5-4).
Figures 5-3 and 5-4 also show that the substrates from Stage 7 were
partially plugged for these runs.  We were unable to clear the jets
without risking alteration of the jet diameter.  With the completion of
sample removal and cleaning of the sampling equipment, the testing phase
was finished.
4.1.6  Post-Test Activities
       Following test completion, sampling system hardware was packed  and
stored onsite  at Exxon  in preparation for the Phase  II sampling program.
Test samples were brought back to Acurex, where  analysis was performed.
4.2    PHASE II - CONDENSATION  TESTS
4.2.1  Procedures
       Equipment setup  and operation was  executed  according  to  an  amended
formal procedure which  was developed from the previous  demonstration
tests.  This defined a  proper  sequence  of assembly  of  the  gate  valves,
probe housing,  ancillary equipment  and  prescribed  probe  setup,  systems
preparations for testing, test sequence,  shutdown  and  sample removal.
       As  in the previous demonstration tests,  all  procedures  followed
the  IERL-RTP Procedures Manual for  Level  1  Environmental  Assessment.
4.2.2  Pretest Activities
       Pretest activities consisted  of  unpacking the probe from Exxon,
storage, setup and  checkout,  and check  fitting  the modified  probe  parts.
Test  preparations were  completed between  May 21  and May  22.   Exxon
personnel  assisted  in the  installation  of heavy equipment  and  utilities

                                     63

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supply.  The previous nitrogen purge gas, probe housing support,  and
cooling water lines were used.
       The front cyclone and filter housing, choked orifice train,
extension tube and rear filter housing were fitted to the outer probe
housing for check fitting and traversed through the operating modes.
During the first traverse through the access valves, the front cyclone
and filter failed to clear the sampling valve seats resulting in  a  damage
to the cyclone nozzle and filter housing.  A redesigned filter housing
which featured a reduced profile and an integrated filter screen  was
machined on May 23 with the assistance of Exxon personnel.  The assembly
was retested May 25 with success.
4.2.3  Runs 1 and 2
       For the first test run, the choked orifice train was not used  due
to an installation problem involving 0-ring seal abrasion.  Instead,  the
                                                                  o
primary flow control valve was set to the desired flow of 0.0144  m  /min
using the previous demonstration test data results.  Following the
prescribed preheating, the duct access valves were opened and the sampling
probe inserted into the duct stream.  The manual ball valve was opened
and the flow measured by the existing orifice within the inner probe.
Sampling continued for 30 minutes with data taken at 5-minute intervals.
The manual ball valve was closed with the flow control valve  left in  its
initial position.  The probe was then withdrawn and gate valves closed.
The system was then cooled and the probe assembly removed and taken to
the lab area for sample recovery and cleaning.  During sample recovery,
it was noted that the front filter had evidence of particulate blowby.
Cleaning solvent rinses were bottled  and labeled for analysis.
                                    64

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       For the second test run, the choked orifice train was installed by
modifying mechanical links for more clearance within the existing
transport tube.  To prevent mechanical abrasion of the 0-ring seals, a
rinse solvent mixture was used as a final rinse and lubricant.  Both test
runs were conducted May 23.
4.2.4  Runs 3 and 4
       For Test Runs 3 and 4, the choked orifice train, extension  tube,
front and rear filters, and the cyclone were used following the identical
procedures and test parameters as Run 2.  Two saffil alumina filters were
"sandwiched" to comprise the front filter in order to minimize
particulate blowby.  Sample recovery  showed little or no sign of
particulate blowby on these runs.  However, chemical analysis of the
cyclone and front filter catch showed significant gold contamination.
This was caused by failure of the cyclone's protective gold plating upon
extended exposure to the PFBC flue gases.  Titanium contamination  due  to
heavy oxidation of the cyclone body was  not evident  in  any of the
samples.  With the completion of  sample  recovery  and cleaning,  the
testing phase was finished.
4.2.5  Post-Test Activities
       The sampling  system hardware was  packed  for  surface shipment back
to Acurex.  Solvent  wash test samples were  sent by  special surface
carrier and test filters were hand-carried  back to  Mountain  View.
Packing and packaging were completed  May 24.
                                     65

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                                SECTION 5
                             DATA AND RESULTS

       This section presents  the detailed information collected and the
results obtained during the complete HTHP sampling system test program at
Exxon's Miniplant.   This section has been divided into subsections which
discuss the individual  data and results from each of the two test series,
the Phase I ~ Demonstration  Tests and the Phase II ~ Condensation
Effects Tests.  The Phase II  discussion also includes a discussion on the
comparative results of both phases of testing.
5.1    PHASE I ~ DEMONSTRATION TEST DATA
5.1.1  Test Conditions
       Plant operating conditions are listed in Table 5-1.  The nominal
conditions were identical for all three sampling runs.  The facility  ran
steadily without interruption during the tests.
5.1.2  Instrument Readings
       The sampling system includes a number of instruments which measure
duct, sample and equipment operating conditions.  Readings from these
instruments are presented in Tables 5-2, 5-3 and 5-4.
       Table 5-2 gives readings from probe assembly  instruments.  Duct
temperature and pressure were typically  about 740°C  (1360°F)  and 860
kPa  (110 psig).  The drop  in temperature from 900°C  (1650°F)  in the
combustor  to 740°C  (1360°F)  at  the  sampling  location  is due to normal

                                     66

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                                            TABLE 5-1.   TEST CONDITIONS
                                    Run:
#2
Date
Time
Ambient temperature
Bed Conditions
Temperature
Pressure (gage)
Ca/Sulphur Ratio
Excess Air
Coal
Dolomite
Flowrate - sm /m1n (scfm)
Average Duct Velocity -
m/s( ft/sec)
3-31-77
3:30 p.m.
18°C (64°F)
900°C (1650°F)
912 kPa (9 atm)
1.25
30%
Champion
Pfzizer
14(544)
2.0(6.7)
4-1-77
10:30 a.m.
21°C (70°F)
900°C (1650°F)
912 kPa (9 atm)
1.25
30%
Champion
Pfzizer
14(546)
1.9(6.3)
4-1-77
2:40 p.m.
19°C (67°F)
900°C (1650°F)
912 kPa (9 atm)
1.25
30%
Champion
Pfzizer
14(546)
2.0(6.7)
CT>

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                                 TABLE 5-2.  PHASE I PROBE  INSTRUMENTATION READINGS

Run No. 1

Insertion
Sample Flow







Shut-off
Run No. 2
Before Insert
Sample Flow
Run No. 3

Insertion
Sample Flow




Time

3:10 p.m.
3:22 p.m.
3:32 p.m.
3:35 p.m.








10:30 a.m.


2:58 p.m.






Elapsed
Time
(minutes)

0
0
0
0.1
5.0
10.0
15.0
20.0
25.0
30.0


0
0.5

0
0
0
0.33
0.67
0.83
1.0
Stack
Pressure
(pslg)

861.8(125)'
861.8(125)"
758.4(110)
751.5(109)
758.4(110)
758.4(110)
751.5(109)
758.4(110)
758.4(110)
758.4(110)


834.3(121)"
827.4(120)

861.8(125)a
765.3(111)





Stack
Gas
Temp
°C(°F)

77(170)
83(190)
738(1360)
732(1350)
732(1350)
727(1340)
716(1320)
716(1320)
716(1320)
716(1320)


91(195)
738(1360)

88(190)
738(1360)
738(1360)
738(1360)
738(1360)
738(1360)
738(1360)
Dowtherm
Inlet
Temp
•C(°F)

222(431)
218(425)
225(437)
225(437)
225(437)
225(437)
225(437)
218(425)
225(437)
225(437)


222(431)
222(431)

222(431)






Dowtherm
Exit
Temp
°C(°F)

216(420)
208(407)
224(435)
224(435)
224(435)
224(435)
224(435)
208(407)
224(435)
224(435)


216(420)
216(420)

216(420)






Sample
Temp
Impactor
Inlet
°C(°F)

-
-
-
-
-
-
-
-
-
-


-
-

-
-
-
-
-
-
-
Sample
Temp
Orifice
Inlet
°C(°F)

161(322)
167(332)
167(332)
178(352)
189(373)
202(395)
210(410)
216(421)
227(441)
237(459)


167(332)
107(225)

164(327)
164(327)





Sample
Temp
Transport
Tube Exit
•CPF)

-
-
-
-
-
-
-
-
-
-


-
-

-
-
-
-
-
-
-
Sample
Flow-
rate
m'/sec » 10'"
(acfm)6

0(0)
0(0)
0(0)
3.45(.73)
3.02(.64)
3.87(.82)
3.92(183)
4.0K.8S)
4.11(.87)
4.15(.88)


0(0)
4.25(.90)

0(0)
0(0)
0(0)
4.29(.91)
4.20(.89)
4.15(.88)

Impactor
Heater
Temp
•CCF)

.
-
-
-
-
-
-
-
-
-


-
-

-
-
-
-
-

-
Transport
Tube
Heater
Temp
'C('f)

232(450)
233(452)
233(452)
233(452)
233(452)
233(452)
229(445)
238(460)
238(460)
238(460)


229(445)
229(445)

229(445)






CT>
oo

-------
                                           TABLE 5-3.   GAS  TRAIN  INSTRUMENT  READINGS
MO

Run No. 1



Start Flow





Stop Flow
Time

3:10 p.m.
3:22 p.n.
3:32 p.m.







Elapsed
Tine

0
0
0
0
5.0
10.0
15.0
20.0
25.0
27.65
Flow-
rate
a'/sec x 10"*
(acf«)
4.72(1.0)*
0(0)
0(0)
0{0)
3.45(.73)
3.02(.64)
3.87(.82)
3.92(.83)
4. 01 (.85)
4.n(.B71
4.is(.sa)
Transport
Line Terap
«C(«F)

229(444)
234(453)
-
-
232(449)
232(449)
231(447)
231(447)
236(456)
232(450)
Flow Control
Oven Tenp
•Ct-F)

232(449)
-
-
-
202(396)
218(425)
237(458)
234(45*)
230(446)
229(444)
Organic
Module
Tenp
-cm

14(58)
-
-
-
21(70)
22(72)
23(74)
22(71)
24(76)
24(75)
Inpinger
Train
lemp
'C('f)

21(70)
-
-
-
21<69)
21(69)
21(70)
2?(7)3
23(73}
23(73)
Anfctent
Ten?
°C(*F)

18(65)



18(64)
18(65)
19(67)
19(67)
18(65}
19(66)
                                                                                                                                 U1
                                                                                                                                  I
                                                                                                                                 oo
                                                                                                                                 £T>

                                                                                                                                 f-
                                                                                                                                 CO
                                                                                                                                 3
                                                                                                                                 73
              At orifice conditions - see Table 4-2.
                                                                                                                                 cn

-------
                        TABLE 5-4.  ANISOKINETIC CORRECTION FACTORS  -  PHASE  I
Run
1
2
3
Sampl e
Flowrate
m'/sec
(acfm)
4.0 x 10""
(0.85)
4.0 x 10""
(0.90)
4.0 x 10""
(0.90)
Nozzle
Velocity
m/sec
(ft/sec)
2.8(9.3)
4.0(13.0)
3.4(11.3)
Estimated
Duct
Velocity
m/sec
(ft/sec)
2.0(6.7)
1.9(6.3)
2.0(6.7)
Velocity
Ratio
0.72
0.48
0.59
Particle Concentration3
Correction Factor
measured
true
0.99
0.98
0.99
Calculation per method in Handbook of Aerosols,  TID-26608,  1976, Section 5.1-1 and Figure 5-2.

-------
system heat losses.  Sample conditioning data showed that the sample gas
was cooled below the desired 230°C (450°F) in passing through the
unheated particle collection device.  In Run 1, with the filter
collector, minimum temperature after the impactor was 107°C  (225°F).
Temperatures did, however, remain above the dewpoint for 97°C
(207°F), 930 kPa (120 psig) 6 percent water (although probably not
above the H2SO. dewpoint).  Consequently, no water condensation
occurred during these tests.  Correcting the impactor heater malfunction
will eliminate the  low collection temperatures  in future sampling.
       The sample flowrate, 380 cm3/s to 425 cm3/s (0.8 to 0.9 acfm)
at orifice inlet conditions, was maintained within the  impactor  operating
range throughout the test  series.  This flowrate gave nozzle velocities
which were somewhat above  duct velocity (anisokinetic).  The flowrate  was
chosen based on  the expected stream  velocity.   Unfortunately,  a  damaged
pitot tube prevented measuring the  velocity  to confirm  the  proper
flowrate  needed  to  maintain  isokinetic  conditions.   However, for the high
gas temperature  and pressure,  fine  particles  and  low velocities  involved,
the variance from  isokinetic conditions  has  no significant  effect on
measured  particulate concentration.   The  error in  measured  particle
content  as  a function  of an  isokinetic  velocity mismatch  can be  estimated
analytically  (see  Figure 5-1).   A comparison  of duct and  sampling
velocities  and the calculated  correction  factors  for anisokinetic
conditions  is  presented  in Table 5-4.   As shown,  the measured  particulate
concentrations are within 1  or 2 percent  of  isokinetic  measurements.
        Table  5-3 lists  the instrument readings from the gas sampling
equipment used during  Run 1.   Gas sample  flow was started  shortly after
particulate sampling began,  so the total  elapsed  time is  less  than shown

                                     71

-------

   2.0
   1.8
   1.6
§  1-«

Z
O
o

UJ
D
CC
o
tr


UJ
O

o
o

o
UJ

cc
UJ
v>
CO
o

u.
O
   1.2
2 1.0
   0.6
   0.4
   0.2
          k = 0.005
          k = 0.02
          k = 0.04
          k = 0.08
          k = 0.14
       . k = 0.32
          k = 1.0
                0.1
                                                                     eo
                                                                     co
                                               "
                                            CcpVd2

                                            18nD
                          where

                           d = diameter of particles, cm

                           p = density of particles,  g/cm3

                           0 = probe  diameter, cm

                           v = probe  inlet velocity,  cm/sec

                           V = main stream velocity, cm/sec

                           n = gas  viscosity, poise

                           Cc = Cunningham correction factor.

                               dimensionless
                                              I
                                                        10
                     0.3         1         3


                      VELOCITY RATIO (R)


Figure  5-1.  Probe inlet bias  (from Reference  3).
                               72

-------
in Table 5-2.  During gas sampling, all sample flow was diverted to the
gas-train, so the flowrates given for the gas train are the same as those
for the parti oil ate collector.  The temperature readings show that all
gas train components were operating correctly.
       During the test series, the surface temperatures of the  access
port, gate valves and probe housing were measured.  These readings are
presented in Table 5-5.  The gate valve surface temperature remained
below 126°C  (258°F) at all times .  Accessible surfaces of the  probe
housing also remained cool, below 75°C (167°F).
5.2    PHASE I  -- DEMONSTRATION TEST RESULTS
       The tests produced data on  particulate concentration,  size
distribution, appearance, chemical composition,  and moisture  content.
Although  trace  organic and trace element  samples  were  collected,
demonstrating that particular HTHP system capability,  the  analysis of
these samples was beyond  the  scope of  the program.
       The measured particle  concentrations  are  listed in  Table 5-6.   The
values of 1.06  to 1.58 g/m3  (0.43  to 0.64 gr/scf) are  reasonable
compared  to  other measurements made  in the unpressurized  portions  of  the
                                                                    3
Exxon process.   Those measurements have ranged  from 0.5 to 2.96 g/m
(0.2 to 1.2  gr/scf).  The 1.58  g/m3  (0.64 g/scf)  value from the
30-minute sample is the  most  accurate  measurement from the current
tests.  It  comes from the largest  sample and best defined conditions.
       The  moisture content  measured in Run 1 was 6.2  percent by volume.
This compares well with  Exxon's  preliminary estimate of 5.8 percent.
        Particle size distribution  information is presented in Figure  5-2
and  Table 5-7.   As  shown, there  is some difference in  the results  from
                                     73

-------
TABLE 5-5.   STRUCTURE TEMPERATURES
Pretest (11:00 a.m.,  3-30-77)

    Duct Wall         176°C (349°F)
    Pressure Cylinder
        Top          146°C (294°F)
        Side         138°C (280°F)
        Bottom        87°C (189°F)
    Gate Valve -  Duct Side
        Top          126°C (258°F)
        Side         104°C (220°F)
        Bottom        91°C (195°F)

Run No. 1 (3:30 p.m., 3-31-77)
Time
0
10 min
20 min
60 min
Valve-
Probe
Side
64°C(147°F)
71°C(159°F)
69°C(157°F)
88°C(190°F)
Inner
Probe
Housing
56°C(133°F)
55°C(131°F)
56°C(133°F)
N/A
Outer
Probe
Housing
56°C(133°F)
68°C(154°F)
75°C(167°F)
N/A
                   74

-------
TABLE 5-6.  PARTICULATE CONTENT
        Run #1
Run
Run #3
Date:
Time:
Particle Catch:
(grams)
Filter
Impactor
Residue
Total
Sample Volume:
m3(scf)
Particle Content:
(9/m3)(gr/scf)
Particle content:
(g/m3)(gr/scf)
(Anisokinetic
Correction Applied)
3-31-77
1530

3.2515
-
1.8565
5.108
3.22(122.5)
1.58(0.64)
1.60(0.65)
4-1-77
1030

-
0.0554
0.0334
0.0884
0.082(3.13)
1.06(0.43)
1.08(0.44)
4-1-77
1500

-
0.0892
0.0595
0.1497
0.132(5.03)
1.13(0.46)
1.16(0.47)
                75

-------
   100

    80


    60



    40
    10

    e
E
a.


&    A
Hi    4

UJ
o
s.
o.
   i.o

   0.8

   0.6



   0.4
   0.2
    0.1
                   10
PERCENTAGE UNDERSIZE (BY WEIGHT)

20   30   40   50   60   70    80
                                                               90
                   90      80    70   60   50   40   30

                               PERCENTAGE OVERSIZE
                              20
                                      10
                                                                             98
                                                     §
                                                     N
                                                     4
            Figure 5-2.   Particle size distribution  — Phase I tests.
                                          76

-------
TABLE 5-7.  PARTICLE SIZE DISTRIBUTION
Stage
1
2
3
4
5
6
7
Filter
D50
Microns
26.0
12.0
4.3
2.1
1.2
0.6
0.3

Run #2
Weight
Collected
0.0076
0.0080
0.0171
0.0139
0.0022
0.0036
0.0020
0.0010
% Total
Weight
13.7
14.4
30.9
25.1
4.0
6.5
3.6
1.8
%
Smaller
86.3
71.8
41.0
15.9
12.0
5.4
1.8

0.0554 grams
Run #3
Weight
Collected
0.0093
0.008
0.0221
0.0215
0.0135
0.0081
0.0039
0.0028
0.0892 grams
% Total
Weight
10.4
9.0
24.8
24.1
15.1
9.1
4.4
3.1
%
Smaller
89.6
80.6
55.0
31.7
16.6
7.5
3.1


-------
the two impactor runs.  However, both show that most of the participate
falls within the 1-to 20-micrometer range.
       The impactor substrates are shown in Figures 5-3 through 5-6.
Generally, the patterns are typical of normal impactor operation.
Stage 7, however, shows evidence of several plugged jets.  A comparison
of Figures 5-4 and 5-5 show the differences in particulate loading for
substrates from Run 2 and Run 3.  Run 2 substrates were lightly loaded,
while those from the longer duration Run 3 showed heavy,
three-dimensional deposits.
       The particulate sample from Run 2 were photographed using a
scanning electron microscope (see Figures 5-7 through 5-10).  The
particulate is irregular in appearance, suggesting that it may be calcium
sulphate crystals from the dolomite bed and ash from low-temperature
combustion.  Some of the photos show congealed masses of particles.  The
source of this phenomena could be any of the following:  a property of
the collected particulate, condensation on the particulate, or the
conductive spray applied to the sample for SEM photography.
       The chemical composition of collected particulate was analyzed by
dispersive X-ray fluorescence analyzer.  Spectra of X-ray emissions are
shown in Figure 5-11.  The peak heights for each element indicate the
relative elemental concentration.  The analysis shows detectable amounts
of aluminum,  silicon, calcium, sulphur, iron, potassium, titanium and
copper.
5.3    PHASE II ~ CONDENSATION TEST DATA
5.3.1  Test Conditions
       Plant operating conditions are listed in Table 5-8.  As in the
Phase I tests, the nominal conditions were similar for all test runs.   In

                                    78

-------
Impactor substrates.
   Impactor  substrates.
        Figure 5-3.
            79

-------
Impactor substrates.
Impactor substrates.
 Figure 5-4.
     81

-------
00
                                                    Figure  5-5.
                                        Impactor  substrate  Run  3,  Stags  5

-------
oo
 n
                                                Figure 5-6.


                                      Impactor substrate — Run 2, Stage 5,

-------
            1000X
             10 Microns
           3000X
           Figure  5-7.
Particle photomicrographs Stage 1
              87

-------
             \ooox
              10 Microns
           3000X

             3 Microns
          Figure 5-8.

Particle  photomicrographs Stage  2,

               89

-------
             1000X
              10 microns
             3000X
              3 microns
           Figure 5-9.
Particle photomicrographs Stage 4.
               91

-------
            3000 X
          10000X
             1  micron
          Figure  5-10.
Particle photomicrographs Stage 6.

               93

-------
          S£^
              Stage  1,  Run 2
          •=COO
                                   U_   O
               Stage 6,  Run  2
Figure 5-11.   Particle checmical  composition.
                     95

-------
                          TABLE 5-8.  EXXON - PHASE II FBC OPERATING CONDITIONS
Run
Date
Sampling Time
Ambient Temperature °C(°F)
Bed Conditions
    Temperature °C(°F)
    Combustor Pressure
     kPa(atm)
    Ca/Sulphur Ratio
Coal
Dolomite
Combustor Flowrate -
 sm^/mi n
Avg. Duct Velocity -
^
n/s
 m/sec(ft/sec)
     1
  5-24-77
1433 - 1503
  32(90)


 893(1640)
   932.2
   1.25
 CHAMPION
 PFZIZER
16.5(628)

2.43(7.97)
                                                      2
                                                   5-24-77
                                                 0900 - 0920
                                                   29(85)
 891(1635)
   932.2
   1.25
 CHAMPION
 PFZIZER
16.6(630)
2.44(7.99)
                          3
                       5-24-77
                     1134 - 1153
                       29(85)
 893(1640)
   922.1
   1.25
 CHAMPION
 PFZIZER
16.6(631)
2.44(800)
      4
   5-24-77
 1700  - 1715
   31(88)


 896(1644)
   922.1
   1.25
 CHAMPION
 PFZIZER
16.8(639)
2.47(8.11)

-------
 fact, the test conditions for both phases of testing were very similar.
 Champion coal from the same shipment and Pfzizer dolomite were used for
 all testing.   Combustor flowrate and average duct gas velocity were
 approximately 15 percent greater in the Phase II tests.   The facility ran
 steadily with no interruptions during the tests.
 5.3.2  Instrument Readings
        The  Phase II  sampling system employed the same instrumentation
 control  modules as the Phase I tests.  Readings of duct,  sample and
 equipment operating  conditions are presented in Table 5-9.
        The  stack gas thermocouple malfunctioned throughout  the four
 tests.   This  temperature was approximated at 732°C (1350°F)  -- the
 average  stack  temperature during the first test series.   Very similar
 PFBC  operating  conditions between the two test series make  this a
 reasonable  approximation.   Another less critical malfunction occurred in
 the transport  tube outlet filter thermocouple.   This problem had the
 nature of an  intermittent electrical short.   Consequently,  the
measurement could be made only periodically.
       The  sample conditioning data showed the sample temperature falling
below the target of  232°C (450°F).   Temperatures sometimes  fell  as
 low as 93°C (200°F)  immediately after the flow control valve and
rarely exceeded  204°C (400°F)  in the transport tube leading  to the
final filter.  Assuming  that flue gas S03 concentrations  are below
30 ppm, as they  are  in conventional  fossil  fuel  fired boilers,  then
Figure 5-12 indicates the  H2S04 dewpoint temperature to be  between
177°C (350°F) and 204°C  (400°F).   Consequently,  it  should be
 expected  that formation  of  sulfuric  acid mist occurred in the transport
 tube.  Upon analysis  of  the  rear  filter  catch,  this was found to be the
                                     98

-------
                             TABLE 5-9.   PROBE  INSTRUMENTATION  READINGS

Run No. 1
5-24-77 Tues.
Zero Point






Closed Ball Valve
Retract Probe
Run No. 2
5-24-77 Tues.
Zero Point



Closed Ball Valve
Retract Probe
Time
of
Day
1333
1351
1358
1404
1408
1412
1416

1420
2100
2105
2110
2115
2119
2122
Elasped
Time
(Mln)
0
5
10
15
20
25
29
30
Stop-off
0
0
5
10
15
19
20
Stop-off
Stack
Pressure
kPa(psl)
882.5(128)
765.3(111)
758.4(110)
758.4(110)
758.4(110)
758.4(110)
758.4(110)

758.4(110)
765.3(111)
758.4(110)
758.4(110)
765.3(111)
765.3(111)
765.3(111)
765.3(111)
Stack
Temp
•cm
M
M
-
-
M
-
-

510(950)
493(920)
493(920)
493(920)
493(920

Dow therm
Inlet
Temp
•C('F)
185(365)
188(370)
182(360)
188(370)
189(372)
188(370)
189(372)

188(370)
182(360)
188(370)
185(365)
187(368)
189(372)
189(372)
182(360)
Dowtherm
Outlet
Temp
*C(°F)
188(370)
193(380)
188(370)
193(380)
194(372)
193(380)
194(381)

188(370)
188(370)
193(380)
193(380)
193(380)
194(381)

188(370)
Traverse
Tube Heater
Temp
2 'C(°F)
206(403)
201(394)
203(397)
203(397)
202(395)
201(393)
202(395)

202(395)
209(409)
203(397)
203(398)
204(400)
206(402)
rintnrf

208(407)
Traverse
Tube Outlet
Temp
3 °C(°F)
41(106)
102(215)
122(252)
125(257)
124(255)
129(265)
129(264)

71(160)
36(97)
141(285
148(298)
144(291)
144(291)
l/j.1 ,,n
Value
86(187)
Traverse
Tube Outlet
Filter Temp
4 «C(°F)
33(91)
34(93)
33(92)
33(92)
34(93)
33(92)
34(93)

33(92)
33(91)
163(325)
173(344)
174(345)
176(349)

84(183)
Sample
Flowrate
ro'/sec x 10"*
(acfm)
2.41(.51)
2.4K.51)
2.41(.51)
2.4K.51)
2.4K.51)
2.4K.51)
2.41(.51)

2.41(.51)
2.41(.51)
2.41(.S1)
2.41(.51)
2.41(.51)
2.41(.51)
2.4K.51)
Transport
Tube Temp
°C(°F)
277(530)
277(530)
277(530)
277(530)
277(530)
277(530)
277(530)

OFF
293(560)
293(560)
249(480)
254(490)
257(495)
257(495)
OFF
Note:  M Indicates malfunction

-------
                                               TABLE  5-9.   (Concluded)

Run No. 3
5/25/77, *d.
Zero Point
Prtstart



Closed Ball Vtlvt


Run No. 4
5/25/77. Wed.




Ball Valve Cloud

Time
Of
Day

11:12 . ,
11:18 . .
11:34 . .
11:41 . .
11:46 . .
11:51

11:58


4:55 p.m.
5:00 p.m.
5:02 p.m.
5:07 P.M.
5:11 P.M.


Elapsed
Time
(rin)

-5
0
0'
5
10
15
19
Stopoff


-5
0
5
10
14
is
01
Stack
Pressure
kPi (psl)

834.3 (121)
841.2 (122)
765.3 (111)
765.3 (111)
765.3 (111)
765.3 (111)

765.3 (111)


634.3 (121)
765.3 (111)
765.3 (111)
765.3 (111)
765.3 (111)


Stack
Temp.
•c ft)

H
H
M
N
M
H
M
N


N
H
N
M

Stopoff
M
Dowtherm
Inlet
Temp.
•C (*F)

188 (370)
189 (372)
188 (370)
194 (382)
191 (375)
188 (370)

177 (350)


191 (375)
196 (385)
192 (378)
193 (380)
196 (385)

179 (355)
Dowtherm
Outlet
Temp.
•C («F)

188 (371)
188 (370)
188 (370)
198 (389)
193 (379)
188 (370)

182 (360)


189 (372)
199 (390)
193 (380)
194 (381)
197 (387)

182 (360)
Traverse
Tube
Heater
Temp.
•C ("F)

211 (411)
208 (407)
211 (411)
206 (405)
206 (403)
206 (402

87 (188)


206 (402)
199 (390)
201 (394)
202 (396)
201 (394)
fait1* Ihwn
Off
Traverse
Tube
Inlet
Temp.
•C CF)

36 (97)
37 (99)
38 (100)
149 (300)
152 (305)
152 (305

79 (175)


41 (105)
135 (275)
151 (303)
148 (299)
142 (288)

78 (173)
Traverse
Tube
Outlet
Filter
Temp.
•C (*F)

34 (93)
35 (95)
37 (98)
172 (341)
177 (351)
179 (354)

._


35 (95)
158 (316)
171 (340)
173 (344)
172 (341)


Sample
Flow Rate
m'/sec x 10'*

2.41 (0.51)
2.41 (0.51)
2.41 (0151)
2.41 (0.51)
2.41 (0.51)
2.41 (0.51)

2.41 (0.51)


2.41 (0.51)
2.41 (0.51)
2.41 (0.51)
2.41 (0.51)
2.41 (0.51)

2.41 (0.51)
Transport
Tube
Temp.
*C (*F)

266 (510)
271 (520)
282 (540)
268 (515)
268 (515)
268 (515)

Off


263 (505)
271 (520 L
266 (510)
266 (510)
271 (520)

Off
o
o

-------
10130 (100)
                                  1  3  10 30 100
  1013 (10)
£
re

re



-------
case (see following section).  This  analysis  also  showed contamination
from the disintegration of control valve  packing  located just  upstream  of
the rear filter.
       Sampling flowrates were predetermined  by assuming a duct velocity,
pressure and temperature, based  on the  Phase  I tests,  and appropriately
sizing a nozzle and the choked orifices to  yield  isokinetic  nozzle
velocities.  The actual sample flowrate gave  nozzle  velocities
approximately 15 percent below duct  velocities.   However, as was the  case
with the Phase I tests, the  high gas temperatures  and  pressures, the  fine
particles and low velocities involved minimized the  effect of
anisokinetic conditions on the measured particulate  concentration.
Furthermore, since the purpose of the Phase II tests was to  examine only
elemental concentrations in  the  hot  and cold  filters,  particle size
biasing caused by anisokinetic sampling conditions was relatively
unimportant.  A comparison of duct and  sampling velocities and the
calculated correction factors for anisokinetic conditions is presented  in
Table 5-10.  The measured particulate concentrations are within 3 percent
of the true concentration.
5.4    PHASE II - CONDENSATION  TEST RESULTS
       The condensation test results section  is divided into three
subsections.  General results and observations of  the  samples, both
visually and by photomicrographs, are discussed first.  Attempts at
comparing the analyses of the hot and cold  filter  catches and  the
associated problems are treated  next.   Finally, an alternate approach to
answering the question of condensation  of trace elements is  discussed.
Tentative conclusions are drawn  from the  limited  data  obtained.
                                    102

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                       TABLE  5-10.  ANISOKINETIC CORRECTION FACTORS - PHASE II
Run
1
2
3
4
Sample
Flowrate
m3/s x 10""
(acfm)
2.4(.51)
2.4(.51)
2.4(.51)
2.4(.51)
Nozzle
Velocity
m/sec
(ft/sec)
2.2(7.1)
2.2(7.1)
2.2(7.1)
2.2(7.1)
Estimated
Duct
Velocity
m/sec
(ft/sec)
2.4(8.0)
2.4(8.0)
2.4(8.0)
2.4(8.1)
Velocity
Ratio
1.13
1.13
1.13
1.14
Particle Concentration3
Correction Factor
measured
true
1.03
1.03
1.03
1.03
Calculation per method  in Handbook of Aerosols, TID-26608, 1976,
 Section 5.1-1  and  Figure 5-2.

-------
5.4.1  General Results and Observations
       Table 5-11 shows particulate  concentration.   As  noted, Run No. 3
samples were, retained by EPA for  SSMS  analysis  and,  consequently, not
weighed.  The reported values for particulate catch  have  been obtained by
using standard EPA drying and weighing techniques.   The values of 0.99 to
2.49 g/m3 (0.40 to 1.01 gr/scf)  are  reasonable  compared to  other
measurements made on the FBC.  As stated earlier,  these values have
ranged from 0.49 to 2.96 g/m3  (0.2 to  1.2 gr/scf)  on a  wet  basis.
A flue gas moisture content of 6  percent could  be  assumed if  it  is
desired to obtain dry basis particulate  concentrations.  This is an
approximate value from the Phase  I test  series.
       Visual observations of  the front  and rear filters  from Tests  1, 2,
and 4 are summarized in Table  5-12.   In  addition,  all these samples  were
photographed using a scanning  electron microscope.
       As in the first test series,  the  particulate  is  irregular in
appearance, suggesting that  it may be calcium sulfate crystals from  the
dolomite bed and ash from low-temperature combustion.   However,  some of
this particulate is undoubtedly  gold deposited  as  a  result  of corrosion,
blistering, and flaking of the gold  plating on  the scalping cyclone.
Chemical analysis of the  hot  filter  catch showed considerable gold
concentrations — many times  greater than would be expected in flyash.
This gold contamination has  little negative effect on the condensation
test results.  The photographs in Figures 5-13  and 5-14 show  agglomerated
particles.  For the front filter, the cause could  be either a property  of
the collected particulate or  the conductive spray applied to  the sample
                                    104

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                   TABLE 5-11.   PARTICULATE CONCENTRATION
                            Run #1
Run #2
Run 14
Date
Time
Participate Catch
(grams)
Cyclone
Front Filter
Rear Filter
Probe Wash
TOTAL
Sample Volume
NmMscf)
Particle Content
g/m3/(gr/scf)
Particle Content
g/mV(gr/scf)
(Anisokinetic
Correction Applied)
5-24-77
1445

1.414
.374
.014
.266
2.068
2.05(78)
1.01 (.41)
.99(.40)
5-24-77
0910

2.354
.654
.014
.469
3.491
1.37(52)
2.56(1.04)
2.49(1.01)
5-25-77
1710

1.243
.598
.006
.359
2.206
1.03(39)
2.14(.87)
2.07(.84)
Note:  Run 3 samples retained by EPA for SSMS analysis - no weights
       available.
                                        105

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             TABLE 5-12.   VISUAL OBSERVATION OF FILTERS - PHASE  II
                      Front
              (all  disintegrating)
          Flesh  color -  fine particles
          light  loading


          Flesh  color -  fine particles
          medium loading
          Flesh color - fine particles
          medium loading
             Rear
Dark tan - very few metal lie-like
particles, medium coating of
fine particles

Dark tan - more metallie-like
particles, medium coating of
fine particles

Grey with a tan tinge -  many
metallic-Tike particles,
light coating of fine particles,
4- to 5-mm hole either abraded
or corroded in center of filter
Note:  No observations made on Test 3 - filters given to
       EPA for SMS analysis.
                                       106

-------
   -.-•
   c


   L
                                                             3 microns
                              3000 X
   n
   E.


                                                             1 micron
Figure 5-13.
               10000 X


Particle photomicrographs -- Run 1, front filter.



                 107

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  c
  =«=
                                                           T3
                                                           CD
                                                           O
                                                           C
•      I
                                                            3 microns
                                        i
                                                              I
                                                            1 micron
                              10000 X
Figure 5-14.  Particle photomicrographs -- Rund 4, front  letter.
                                109

-------
for SEM photography.  For the rear filters, shown in Figures 5-15  and
5-16, these causes are again possibilities, in addition to the known
existence of H^SO, condensation and valve packing contamination.
       The rear filter for Test 4, shown in Figure 5-15,  is noticeably
lighter in particulate than Tests 1 and 2 rear filters  (Figure 5-13).
This is because two front filters were used in Test 4 while only one was
used in Tests 1 and 2.  Figure 5-17 shows a photograph  and a dispersive
X-ray analysis of a blank rear filter.  Dispersive X-ray  fluorescence
analysis for the Test 4 front filter  (Figure 5-18) shows  detectable
amounts of aluminum, silicon, sulfur, potassium, calcium, titanium,  and
iron.  The rear filter analysis from  the same test shows  that the
compounds of most elements almost completely filtered out in the front
filter.
       The cyclone used was  a Southern Research  Institute model designed
for much less severe operating temperatures.  It was  readily available,
was small enough for insertion into the duct, and had a very efficient
0.6 micron cutpoint.  As previously mentioned, the cyclone's protective
gold plating blistered and peeled,  leaving titanium  surfaces exposed to
heavy oxidation.  Chemical analysis of the particulate  samples  showed
significant gold contamination in the cyclone and front filter  catches
but none in the rear filter  catch.  Titanium contamination was  not
evident in any of the samples.
5.4.2  Initial Analyses for  Condensation Effects
       The original  intention of the  Phase II tests  was to compare the
elemental concentrations found in the filtered material of the  in-stack
scalping cyclone and backup  filter with the material  caught  on  the rear
filter.  If the system worked  ideally, one could  assume all  the material

                                    111

-------
  ro
  a;
                                    3 microns
                  3000 X
  re
  
-------
 t

                                                             I
                                                          3 microns


 -
=«=

     N
    W

                            10000 X
                                                          1 micron
   Figure 5-16.   Particle photomicrographs -- Run 1, rear filter.
                              115

-------
_^
c
-:

I
                                                          1 micron

                           10000 X


        Particle photomicrograph — blank rear filter.
*
c
03

CO

      Particle  chemical  composition  - blank rear filter.




                          Figure  5-17.


                               117

-------
c
o
S-
                                            a;  o;
                           Front  filter
-
-
- :

:
                 
-------
on the rear filter was in a gaseous state at stream conditions and would
thereby pass through the hot cyclone/filter combination  and thus be
indicative of condensation products produced within the  probe.
Unfortunately, the rear (or cold) filter could not be reliably analyzed.
Carryover of glass fiber filter material during sample preparation (the
small amount of the sample available on the cold filter  and additional
contamination already mentioned), yielded poor detection  limits with the
spark source mass spectrometer (SSMS).  Moreover, the values  reported for
this filter were in mass units rather than concentration  units because a
net filter collection weight was not determined.  This made any direct
comparisons of cold and hot catches from Phase II results  alone difficult
if not speculative.
       Samples of the probe wash were analyzed by Arthur  D. Little,  Inc.,
to determine the source of the suspected contamination of  the rear
filter.  A sample from each test was analyzed by thermal  gravimetric
analysis (T6A), infrared analysis (IR), X-ray fluorescence (XRF), and low
resolution mass spectra (LRMS).  Results indicated there  were three
sources of contamination.  They were by weight: (1) approximately 30
percent particulate ~ attributed to hot, in-stack filter  breakthrough,
(2) approximately 25 percent sulfuric acid and sulfate condensate --
attributed to localized cold spots (measured at 200°F, below  the
H2S04 condensation temperature), and (3) approximately 40  percent
organics — later attributed to the disintegration of packing material
from a valve located just upstream of the rear filter.   The evidence of
breakthrough particulate contamination was supported by  photomicrographs,
which showed similar appearance between material on the  front and rear
filters, and by dispersive fluorescent X-ray spectrum which shows a

                                   121

-------
similarity in chemical composition.  The sulfur content did, however,
increase on the rear filter, apparently as a result of sulfate
condensation.
5.4.3  Alternate Approach
       An alternate approach was taken to resolve the question of trace
metal condensables.  During the Phase I demonstration tests at Exxon,  a
test run was made at essentially the same operating and stream conditions
as the Phase II tests.  A total mass filter was used in place of the
cascade impactor and was maintained at about the same temperature as for
Phase II.  Northrop Services, Inc.  performed a SSMS analysis of the
Phase I bulk filter catch, as they did with the Phase II hot
cyclone/filter samples.
       Table 5-13 presents the results for these analyses.  The measured
elemental content is similar to common flyash.  A partial,
nondimensionalized comparison of these two sets of results, Phase I and
Phase II, is presented in Table 5-14.  Reference quantities Fe and Mg,
have been chosen to nondimensionalize the results because they exist in
significant concentrations in each sample and are not likely to be
present as a result of contamination.  Nondimensionalizing was done
because there appeared to be a diluent present in the Phase I sample
filter catch.  The Si concentrations indicate that the filter material
itself may be the diluent in the sample.  In fact, the sample analyst
acknowledged some difficulty with separating the sample from the
filtering media prior to analysis.
       Aside from the silicon results, comparison of the other quantities
shown indicates that there was no detectable change in the concentration
of Na or K from the hot to cold particulate catches.  It should be

                                   122

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                                 TABLE  5-13.
CONCENTRATION OF ELEMENTS IN FLYASH

SSMS ANALYSIS (PARTIAL)

Element
K
Na
Rb
/%_
cs
Al
S1
Fe
Ca
Mg
T1
Sr
Ba
A..
Au
P
Cu
Zr
N1
Cr
Pb

Cyclone
(ppm)
8,200
1,310
< 70
67
./
164,000
94,000
30,000
20,000
11,400
2,430
810
710
£cn
650
276
248
160
120
< 90
85
TEST #3
Front
(ppm)
8,850
2,500
< 68
oo
.tO
94,000
82,600
13,400
19,000
17,800
1,950
555
694
1 1 Q
1 10
223
165
140
100
< 140
75
- PHASE II
Rear
(ppm)
15.1
< 135. *
< .43 *
^ co *
< .DC
64.2
<2510. *
60.
< 6.6 *
38.
7.1
.6
< 5.0
x 1 A
< \ .H
< 224. *
< 1.5 *
< 2.1 *
5.8
< 13.1
< 4.0 *

Rear Blank
(ppm)
5.4
91.
.13


6.4
1210.
2.36
7.3
5.9
3.1
1.15
1.5


68.
.91
.64
.29
6.4
1.2
PHASE I
Bulk Filter
(ppm)
16,250
3,560
866
80
• o
Major
310,000
36,300
44,000
28,600
10,600
1,320
1,080
?n
C. t O
1,880
142
334
348
366
86
ro
co
      Notes:   <  -  natural  background  limited  detection  limit

              <* -  blank limited  detection  limit

-------
TABLE 5-14.   PARTIAL COMPARISON OF FRONT AND REAR PARTICULATE
             CATCHES FROM EXXON TEST SERIES I AND II

K
Na
Fe
S1
Fe
Ca
Fe"
Mg.
Fe
Sr
Fe
Ba
Fe"
K
M?
Na
*?
S1
Mg
Fe
Mg
Ca
M?
Sr
M?
Ba
Mg
Phase I Tests
Bulk Filter

0.45
0.10
8.54
1.23
0.79
0.04
0.03
0.57
0.12
10.84
1.27
1.56
0.05
0.04
Phase II Tests
Cyclone Front Filter Avg.

0.27 0.66 0.47
0.04 0.19 0.12
3.13 6.16 4.65
0.67 1.42 1.05
0.38 1.33 0.86
0.03 0.04 0.04
0.02 0.05 0.04
0.72 0.50 0.61
0.11 0.14 0.13
8.25 4.64 6.45
2.63 0.75 1.69
1.75 1.07 1.41
0.07 0.03 0.05
0.06 0.04 0.05
Ratio

0.96
0.83
1.84
1.17
0.92
1.00
0.75
0.93
0.92
1.68
0.75
1.11
1.00
0.80
                              124

-------
stressed that these are very limited data from two tests taken at
different times comparing hot and cold filter catches.  However, the PFBC
was using the same coal and dolomite under very similar operating
conditions for both tests, thereby supporting the validity  of the
comparison.  Further testing is recommended  to provide data points  at
other PFBC operating levels and possibly with different filtering media
and collection temperatures.
                                    125

-------
                                SECTION 6
                               CONCLUSIONS

       The sampling system described in this report demonstrates that
extractive sampling is a feasible approach for sampling high-temperature,
high-pressure processes.  In addition, the limited data obtained at one
PFBC operating level  during the Phase II condensation tests, seems to
indicate that trace element condensation would have minimal effect on
particulate composition collected at a low temperature (approximately
400°F).  Technology for sampling pressurized fluidized bed combustors
is now developed and  available.  Future development also will be required
to make useful application of this technology and extend it to other
advanced coal conversion processes.
       One of the remaining issues for FBC high-temperature,
high-pressure sampling is system cost/performance trade-offs.  Process
developers seem to be interested in both upgraded and downgraded versions
of the sampling system.  Upgraded versions offer longer sampling
durations, quicker turnaround and better operating convenience.
Downgraded versions,  such as fixed-probe designs, are cheaper, but give
less information.
                                   126

-------
       The next objective for extractive sampling  is  to  develop  sampling
technology for gasifiers.  Participate measurement  is  also  important  for
developing these processes, and environmental difficulties  are even more
severe than for PFBC's.
                                    127

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                                REFERENCES
1.  Hamersma, J. W.,  et.  al., "IERL-RTP Procedures Manual:  Level 1
    Environmental Assessment," EPA-600/2-76-160a, June 1976.

2.  JANAF, "Thermochemical Tables," Second Edition, the Thermal Research
    Laboratory, Dow Chemical Company,  Midland, Michigan, 1971.

3.  Dennis, Richard,  "Handbook on Aerosols," U.S. Energy Research and
    Development Administration, 1976.
                                   128

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TECHNICAL REPORT DATA
(Please read tmtructions on the reverse before completing)
1. REPORT NO. 2.
EPA-600/7-78-158
4. TITLE AND SUBTITLE
Sampling System Evaluation for High-temperature ,
High-pressure Processes
7. AUTHOR(S)
William Masters, Robert Larkin, Larry Cooper,
and Craig Fong
&. PERFORMING ORGANIZATION NAME AND ADDRESS
Acurex Corporation/Energy and Environmental Division
485 Clyde Avenue
Mountain View, California 94042
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
August 1978
6. PERFORMING ORGANIZATION CODE
8, PERFORMING ORGANIZATION REPORT NO,
10. PROGRAM ELEMENT NO.
EHE623 and 624
11. CONTRACT/GRANT NO.
68-02-2153
13. TYPE OF REPORT AND PERIOD COVERED
Final; 3/76-7/77
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTES J.ERL-RTP project officer is William B. Kuykendal, Mail Drop 62,
919/541-2557.
16. ABSTRACT The report describes a sampling system designed for the high temperatures
and high pressures found in pressurized fluidized-bed combustors (PFBC). The sys-
tem uses an extractive sampling approach, withdrawing samples from the process
stream for complete analysis of particulate size, mass concentration, shape, and
chemical composition. Two series of tests were run at Exxon's pilot-scale PFBC
in  Linden, New Jersey: the first was run to measure particulate mass and size distri-
bution (particulate sizing was achieved using a commercial cascade impactor opera-
ting at about 105 C); the second was run to determine if condensation occurred between
the process temperature of 720 C and the impactor temperature.  Results show that
cascade impactors can be successfully used for sizing in the high-temperature, high-
pressure process  stream of the PFBC, and that condensation was not a problem in
the tests conducted.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Pollution
Sampling
Extraction
Evaluation
High Temperature
Tests
Condensing
8. DISTRIBUTION STATEMENT

Unlimited
High Pressure Tests
Fluidized Bed Pro-
cessors
Analyzing
Dust
Impactors




b.lDENT!FIERS/OPEN ENDED TERMS
Pollution Control
Stationary Sources
Particulate
Mass Concentration
Cascade Impactors


19. SECURITY CLASS (This Report)
Unclassified
2O. SECURITY CLASS (This page)
Unclassified
c. COSAT1 Field/Group
13B
14B
07A/13H 131

11G

07D
21. NO. OF PAGES
134
22. PRICE
 PA Form 2220-1 (9-73)
129

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