x°/EPA
United States
Environmental Protection
Agency
Environmental Sciences Research
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S2-80-202 Feb. 1981
Project Summary
Metal Particulate Emissions
from Stationary Sources
Volume 1. Standard Sampling
and Analysis Method
A program was undertaken to
develop reliable methods for measur-
ing trace elements in emission
streams. This program concerns a
sampling and analysis method for
arsenic (As), cadmium (Cd),
chromium (Cr), cobalt (Co), manga-
nese (Mn), nickel (Ni), lead (Pb), sele-
nium (Se), and vanadium (V). Based
upon a review of the literature, atomic
absorption spectrophotometry was
selected as the analysis method for all
metals. To approximate a stationary
source, a simulation system consist-
ing of a fuel oil combustion chamber
and stack with sampling ports was
constructed. Known amounts of
metals were introduced to the system
as organometallic additives to the
fuel. Flue gas sampling was carried
out simultaneously with two trains
permitting a direct comparison of
changes in configuration, impinger
solutions and sample recovery proce-
dures. Based upon replicate experi-
ments, precisions of 7 to 11 percent
were obtained for all elements except
As (15 percent) and Se (21 percent).
Accuracies of Co, Ni, Mn, Cd, Cr and
V were within 15 percent at the 100
ug level, with Pb being 31 percent
high and As and Se being low by 32
and 48 percent, respectively.
This Project Summary was devel-
oped by EPA's Environmental
Sciences Research Laboratory,
Research Triangle Park, NC, to
announce key findings of the research
project that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).
Introduction
The objective of this work under EPA
Contract No. 68-02-1219, is to develop
reliable methods for sampling and
analysis of potentially hazardous metal
species present at trace levels in emis-
sion streams.
Because of their submicron particle
size, typically reported to be in the range
of 0.1 - 1 (jim, collection by present
control systems is not very efficient.
This report describes the develop-
ment of standard sample collection and
analysis methods for As, Cd, Cr, Co, Mn,
Ni, Pb, Se and V, and an evaluation of
the promulgated test methods 101 and
104 for mercury (Hg) and beryllium (Be),
respectively.
Conclusions
An evaluation of the collection and
analysis of known levels of As, Cd, Co,
Cr, Mn, Ni, Pb, Se and V (and, in some
cases. Be) from stack emission samples
leads to the following conclusions:
• A single stack emission sample can
be analyzed for all metals of interest.
The procedure uses a Method 5-type
sampling train with a quartz filter and
0.1 M nitric acid wet impingers.
Special glassware precleaning and
train cleanup procedures are
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required. After a nitric acid digestion
of the combined samples from the
collection train, analysis for each
element is carried out by atomic
absorption spectrophotometry.
Based on nine replicate experiments
at sample levels of about 100//g for
each metal, sampling and analysis
yields a precision of 7 to 11 percent
for all elements except As (15
percent) and Se (21 percent). The fol-
lowing accuracies (expressed as per-
centages) were obtained:
Pb
Cd, Cr, V
Mn
Co, Ni
As
Se
+31
+ 13 to 16
+6
-2 to -4
-32
-48
• The poor recoveries for As and Se
may be due to incomplete combus-
tion (oxidation) of the organometallic
additives for these compounds, as
the hydride evolution method is only
suitable for the inorganic species of
these elements.
• Analysis of Beat levels of 1 and 10/ug
yielded good recoveries by Method
104 and by the sampling and
analysis method described here for
other metals.
• Evaluation of Method 101 for Hg
yielded good recoveries at 1 ug level.
For best accuracy, the average of at
least 10 measurements of peak
height should be used for analysis.
Recommendations
Further work is recommended with
respect to simplifying the sampling train
precleaning and sample recovery proce-
dures and to improving the precision
and accuracy for the analysis of As, Se
and Pb.
Presently, the glassware is rinsed
with concentrated HNOs during pre-
cleaning and sample recovery. It is
recommended that the effectiveness of
a 0.1 N HNOa rinse be evaluated. Be-
sides reducing the risk of injury to
operating personnel, this would reduce
the number of samples to be collected.
Furthermore, if shown to be suitable for
sample recovery, the influence of 0.1 N
HNOa on the stainless steel nozzle
should be evaluated with a viewtoobvi-
ating the need to remove the probe liner
for cleaning.
The low recoveries obtained for As
and Se and the high recovery for Pb
indicates problems with the sampling
and analysis methods for these ele-
ments. Further studies should be con-
ducted to identify the source of loss (or
gain) for these elements. Specific areas
to be considered include trace metal
introduction into the combustion gas
stream, losses within the combustion
system, adequacy of the sampling train
to collect these elements, recovery from
the sampling train, sample workup
procedure and analysis method.
This Project Summary was authored by Staff of the Center for Environmental
Research Information. USEPA. Cincinnati, OH 45268.
Roy L. Bennett is the EPA Project Officer (see below).
The complete report, entitled "Metal Paniculate Emissions from Stationary
Sources: Volume 1. Standard Sampling and Analysis Method," (Order No.
PB 81-120 024; Cost: $11.00, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield. VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Sciences Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
U.S GOVERNMENT PRINTING OFFICE. 1961 -757-012/7027
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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Agency
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