United States Environmental Protection Agency Industrial Environmental Research Laboratory Research Triangle Park NC 27711 Research and Development EPA-600/S7-82-065a Mar. 1983 <&Efir\ Project Summary The Adipic Acid Enhanced Flue Gas Desulfurization Process for Industrial Boilers: Volume 1. Field Test Results P. A. Clarke, R. W. Gerstle, D. S. Henzel, K. W. Mason, and S. R. Sabatini This study evaluated the effect of adding adipic acid on the SCfe removal of a wet limestone flue gas desulfurization (FGD) system on a coal-fired industrial boiler at Rickenbacker Air National Guard Base near Columbus, OH. Emis- sion data were collected in accordance with the regulations for SOa compliance data specified in the Federal Register. Test results show that adding adipic acid to the limestone slurry significant- ly improved the SOj removal efficiency of the FGD system. Limited baseline data on operations with limestone only indicated a performance level of 55 percent SO2 removal. Adding about 2200 ppm of adipic acid to the lime- stone scrubbing systems, the unit's level of performance increased to an average of 94.3 percent SO2 removal which was maintained within a standard deviation of 2.2 percent over a 30-day test period during which boiler load was 70 - 130 million Btu/hr and gas throughput varied 300 percent. This Project Summary was devel- oped by EPA's Industrial Environmen- tal Research Laboratory. Research Tri- angle Park. NC, to announce key find- ings 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 report describes how the addition of adipic acid to a wet limestone scrubber system affects sulfur dioxide (S02) re- moval efficiency. The site selected for the test, Rickenbacker Air National Guard Base (RANGB) near Columbus, OH, has six spreader-stoker boilers with a total capacity of 222 GJ/h (210 x 106 Btu/h). The boilers produce hot water, primarily for space heating. S02 emissions are controlled by a scrubber system manu- factured by Research-Cottrell under license from A. B. Bahco of Sweden. The FGD system, shown in Figure 1, consists of a mechanical collector, Swedish Bahco scrubber tower, limestone storage and handling system, clarifier (thickener), booster fan, sludge disposal pond, and associated ductwork, pumps, and con- trols. Table 1 gives key design parame- ters for the scrubbing system. During the test a mechanical dry feeder introduced the adipic acid into the scrubber system at the same location where fresh lime- stone is added. Untreated flue gas from the individual boilers enters a common header equipped with a bypass stack and is fed through a mechanical collector for primary removal of particulates. The design removal effi- ciency of the mechanical collector is 70 percent. A fan then introduces the par- tially cleaned flue gas into the scrubbing tower for SC>2 removal. The Bahco scrubber is a tower con- sisting of two inverted venturi scrubbing stages. Untreated gas entering the first stage is diverted down to impinge on the liquid slurry surface of the mill. The gas then rises through the first stage venturi, where it intimately mixes with the slurry droplets now entrained in it The partially scrubbed gas is then diverted down onto the liquid slurry surface in the second- ------- Table 1. Design Process Information for Rickenbacker Air National Guard Base Scrubbing System Total rating Number of boilers Boiler capacity Number of separate FGD units Control system vendor Type of FGD system Start-up date SO2 removal efficiencies Paniculate removal efficiency Water makeup Sludge or by-product disposal 2600 Nm3/s f55,000 scfm) 6 222 GJ/h (210 x 1& Btu/h) 1 Research- Cottrell/Bahco Retrofit March 1976 90%+ design with lime operation; lower with limestone operation 98% design Open loop Unstabi/ized CaS03/SO4 sludge to lined pond stage pan, and the process is repeated. The treated gas is then directed up into a cyclonic mist eliminator, where entrained slurry droplets are removed before the gas exits through a stub stack to the atmosphere. A certified extractive continuous emis- sion monitor (CEM) system and an onsite computer measured and recorded con- centrations of SC>2 and 02 in the flue gas stream. Equipment at RANGB includes a continuous SOa monitoring system on the scrubber, which was used during the test after some maintenance work and calibration. Research Triangle Institute, under contract to EPA, audited the moni- toring system on March 5 and 6, 1981, and found it to be operating properly. Both the certification (based on Federal Register procedures) and internal audits (based on certified 862 and 02 gases) showed that the monitors were operating properly. Some problems entailing un- scheduled maintenance were encoun- tered during the initial 168-hour monitor conditioning period. Also, on March 20 a small leak was discovered in the SO2 monitor internal valving system. Appar- ently, rich inlet gas had leaked through this valve into the outlet gas sample stream, causing a slightly higher outlet SC>2 concentration reading and corres- pondingly lower calculated SO2 removal efficiency. The extent of the leak was determined by introducing audit gases and making manual S02 tests of the flue gases; a correction factor was applied to the outlet readings from March 18 until the leak was repaired on April 3. Test Procedure The adipic acid test period at RANGB was from February 9 to April 10, 1981, during which time the equipment was set up and calibrated and data were collected The monitoring equipment began operat- ing on February 13, but the first few weeks of the test were used for shake- down and calibration of the monitors. The data collected included measured SC>2 and 02 concentrations in the gas stream at the scrubber inlet and outlet and chemical analyses of the scrubber slurry, limestone, and coal. Scrubber and boiler operating conditions were recorded sev- eral times daily. The adipic acid feeder was set up for continuous addition of the adipic acid to the slaker--the same location at which fresh limestone is added. When large quantities were necessary to increase slurry concentrations, the adipic acid was manually introduced directly into the thickener tank because the sudden addi- tion of adipic acid in large quantities to the slaker caused foaming in the slurry. This did not occur in the thickener. Slurry was analyzed at the site, but periodic samples were also checked at the Base laboratory for quality control. The adipic acid analytical procedure uti- lized silicic acid and provided the con- centration of all carboxylic acids, not just adipic. As indicated by the numbers in Figure 1, liquid samples were taken at (1)the limestone slurry feed into the scrubber, (2) the second-stage level tank, (3) the mill recycle loop (known as the' mill pump sample), (4) the thickener inlet stream, (5) the thickener overflow, and (6) the thickener underflow stream. Be- cause the limestone slurry feed sample was used as a control sample, it was taken twice a day. The mill pump sample was taken once a day, and samples were taken from all six locations once a week. Slurry solid samples, taken by filtering samples from the liquid sample streams, included the limestone slurry feed (once a week), the thickener inlet (three times a week), and the thickener underflow(once a week, usually while sludge was being pumped to the settling pond). Coal samples were taken once a day, and limestone samples were taken once a week. The coal samples were combined into weekly composites before being analyzed. For highest S02 removal efficiency, best limestone utilization, and most effi- cient use of adipic acid, optimum scrubber operation was maintained by keeping the pH of the limestone dissolver tank slurry near 5.0. This was done by manually adjusting the limestone feed rate to correspond with changes in the boiler load. Except during occasional upsets in scrubber operations, the adipic acid feed rate remained constant at a concentra- tion of 2000 - 2500 ppm throughout the test. On March 20 and 21 the limestone feed rate and adipic acid concentrations were increased in an effort to achieve still higher S02 removal efficiency. From March 4 to April 10 the test was interrupted only twice because of scrub- ber operation. On March 23 the electrical power to the scrubber was interrupted, and on March 30 the scrubber was shut down because the thickener tank had plugged (apparently as the result of some plastic sheeting) and remained down until 8 a.m. on April 1. On April 10 the addition of adipic acid was stopped, and the continuous monitoring program was terminated. Sufficient data had been accumulated by that time, and warmer weather was resulting in increasingly reduced boiler loads. Quality Assurance Plan for Continuous Monitoring PEDCo performed a quality assurance check on the continuous emission moni- toring system (CEMS) to ensure the reli- ability of the data collected. The check consisted of two distinct but equal func- tions: (1) assessment of the quality of the CEMS data by estimating precision and accuracy, and (2) the control and improvement of the quality of the CEMS data by implementng quality control policies and corrective actions. The second function was related to the first in that determination of data quality inade- quacy resulted in an increase in the quality control effort until the data were considered acceptable. The field operations included stan- dard daily procedures for ensuring that the following activities were performed adequately. Calibration of the CEMS The CEMS was calibrated with gases of known S02 concentrations. Two gases and ambient air were run through the analyzer for each test mode (inlet and outlet). The results of each were re- ------- Sfac* • Adipic Acid Feeder . Limestone — — J| Feeder Tl—I Limestone, Truck ~"b Makeup Water t t Outlet SO2 Probe Thickener .Limestone Storage Overflow to Limestone Feed Tank To Mill Sump Seal Water Sludge To Pond • Bypass Makeup Stack Flue Gas From Heat Plant Unloading Station Mill Pump Recycle From Thickener Underflow Figure 1. Flow diagram of the scrubber system at ftickenbacker. corded, and any necessary adjustments were made. All activities involved in routine cali- bration and adjustment of the CEMS were recorded daily in a standard calibration data log. Calibration of Drift Determination Daily initial calibration readings for all CEMS zero and span values were com- pared with the final calibration readings of the preceding day to determine if any change had occurred in 24 hours. Seven consecutive sets of these initial/final readings were recorded for each parame- ter to determine 24-hour drift Preventive Maintenance for CEMS The CEMS was regularly inspected for problems that might lead to loss in opera- bility or data quality. Each day the four separate systems of the CEMS were checked independently: the SO2 analy- zer, the 02 analyzer, the instrument recorders, and the sampling interface. Program of Corrective Action for Malfunctioning CEMS Any CEMS malfunctions discovered during preventive maintenance checks prompted immediate corrective action. A complete log of all CEMS malfunctions and corrective actions was maintained. Accuracy Assessment PEDCo performed relative accuracy tests on the CEMS according to EPA reference methods and system audits with EPA-tested audit gases based on Standard Reference Materials (SRM). Figures 2 and 3 show the locations of the CEM probes and reference method sampling ports for the inlet and outlet Inlet and outlet sampling locations were selected to represent the streams tested and to achieve equivalence between manual and CEMS samples. Performance Specification Test Regu- lations require that a minimum of 9 and a maximum of 12 sets of reference method data be taken at a rate of no more than one set per hour. Regulations also require that the analyzer monitor stack gas concentrations continuously during refer- ence method testing. All data derived using the reference method and the continuous monitor are given on a dry basis; a moisture correc- tion factor is used to give results on a consistent basis. SO? and oxygen tests were run simultaneously. The CEM anal- ysis of moisture content was determined by measuring the temperature of a sample taken after the moisture trap in the samp- ------- Reference Method Sample Ports Continuous Reference ;*.» A lathnei Probe Ports i Induced Draft Fan I 76 cm £ V . IT nl JO in.) H 11 J ^r^^"Tr" f 129.5 cm (51 in.) • — J — ^ u 722 cm frL — 760 c/r?_. 1 (48 in.) (63 in.) Scrubber Module Figure 2. Scrubber inlet sampling locations. ling system. Moisture content was then calculated because the gas stream being analyzed was saturated. Tables 2 and 3 give the relative accura- cy data for the initial certification period. Relative accuracy, based on nine sets of reference method data, was calculated according to equations in Section 7, Appendix B, Federal Register, Vol. 44, No. 197. These calculations showed that the relative accuracy at the inlet was 1.72 percent (based on S02 concentrations) and 7.30 percent (with S02 expressed on a weight per heat input basis). The corresponding values at the scrubber outlet were 18.67 and 16.43 percent, respectively. Performance Audits Performance audits were conducted to maintain quality control throughout the monitoring period. Audit gases certified by the EPA were introduced at the scrubber inlet through a manifold pres- surized to 3.39 kPa(1 in. Hg) to duplicate sampling conditions. Audit gases were introduced at the scrubber outlet through an open-end manifold at ambient atmos- pheric pressure. No adjustments were made to the analyzer flow rates. Analyzer response to audit concentrations was determined by the computer used for storage and retrieval of the emission monitoring data. Results of these tests showed excellent agreement between the audit gas concentrations and analyzer readings for SOa and oxygen at both the inlet and outlet Results Table 4 summarizes the daily average SOa monitoring data for those 30 days when 18 hours or more of acceptable readings were obtained and high effi- ciency was achieved. These data show that 94.3 percent was the mean removal efficiency, with a corresponding standard deviation of 2.1. These data do not include days when the limestone feed rate was low or when other known operating problems occurred. The emis- sion values are based on an F factor of 2.63 x 10'7 m3/J (9780 dscf/106 Btu). The average inlet SOa loading for the test period was 2125 ng/J (4.94 lb/106 Btu) of heat input to the boiler; whereas, the average SOa outlet value measured was 122 ng/J (0.28 lb/106 Btu). Limited data obtained on February 12 - 16, before adding adipic acid, showed scrubber removal efficiency of 45 - 65 percent. Analyses of the coal burned during the initial monitor operating period and the test period are shown in Table 5. These data show that the coal sulfur content during the continuous monitoring period was 2.22 - 3.55 percent by weight on a dry basis. Based on these data, the calcu- lated SOa emission rate (assuming that 95 percent of the sulfur is converted to SO2) was 1299 - 2210 ng/J (3.02 - 5.14 lb/106 Btu). The average daily feed rates for lime- stone and adipic acid for the entire test period are shown in Table 6. This table also gives the quantity of coal used per day, which indicates the variation in boiler load. From March 4 to April 10, 1981, coal usage varied from 60.8 to 138 Mg/day (55 to 125 tons/day), reflecting the effect of changes in daily temperature on the boiler heat output demand. Of particular interest is the ratio of adipic acid to limestone used to maintain the high SOa removal efficiencies during the test the ratio varied from 6 to 30 g/kg(12 to 60 Ib/ton) and averaged 1 2 g/kg (24 Ib/ton). Uniform limestone and adipic acid addition was difficult to maintain because of the use of manual controls, the varying boiler load, and the inter- mittent discharge of sludge to the holding pond. Conclusions The project resulted in the successful completion of a certified continuous SOa monitoring performance test which veri- fied that the addition of adipic acid did enhance the SOa removal capability of the Rickenbacker FGD limestone control unit without having any adverse effect on operating parameters. Before the test, this limestone scrubber was achieving about 55 percent SOa removal. The adipic acid additive increased the unit's SOa removal efficiency to 90 - 97.4 percent (averaging 94.3 percent) over a 30-day test period. ------- Reference Method Train 166.4 cm (65.5 in.) Inside Diameter Continuous Monitor Reference Method Sample Port Continuous ^ Monitor Location Figure 3. Scrubber outlet sampling locations. Table 2. Inlet Reference Method and CEM Results Reference method Monitor3 Test Vmb (std) (JO-4 No. Time NrrP RIC-1 O749-O819 O.O251 RIC-2 0926-0951 O.0257 RIC-3 1010-1035 0.0254 RIC-4 1110-1135 0.0257 RIC-5 1210-1235 O.0254 RIC-6 1310-1335 0.0274 RIC-7 1410-1435 O.0277 RIC-8 1510-1535 0.0265 RIC-9 1610-1635 O.0278 RIC-10 1710-1735 0.0286 a Three monitor readings taken (dscf) (0.888) (0.908) (0.897) (0.908) (0.896) (0.967) (0.979) (0.937) (0.982) (1.01) g/Nm3 2.03 2.15 2.11 1.94 1.76 2.02 1.92 1.83 1.83 1.86 during reference Ib/dscf) (1.27) (1.34) (1.32) (1.21) (1. 10} (1.26) (1.20) (1. 14) (1. 14) method run. SO2, ppm 775 816 802 734 671 766 753 693 697 703 (ib soy ng/J 1965. 1 1849.0 1849.0 1840.4 1831.8 1763.0 1737.2 1732.9 1732.9 1775.9 Monitor readings 106 Btit (4.57) (4.30) (4.28) (4.28) (4.26) (4. 10) (4.04) (4.03) (4.03) (4. 13) were then <) %O2 15.2 14.5 14.6 15.1 15.6 14.6 14.6 15.1 15.1 15.1 averaged S02, ppm 753 803 805 736 668 793 768 694 689 707 for final (ib soy ng/J 1930. 7 2132.8 2029.6 1887. 7 1711.4 1874.8 1874.8 1874.8 1797.4 1724.3 emission 10s Btu) (4.49) (4.96) (4. 72) (4.39) (3.98) (4.36) (4.36) (4.36) (4. 18) (4.01) results. %02 14.9 15.1 14.8 14.9 14.9 14.4 14.6 15.2 15.0 14.6 b Vm = metered volume (dry basis). ------- Table 3. Outlet Reference Method and OEM Results Reference method8 Monitor Test No. ROC-1 ROC-2 ROC-3 ROC-4 ROC-5 ROC-6 ROC- 7 ROC-8 ROC-9 ROC- 10 ROC- 11 ROC-1 2 Time 0832-0857 0952-1017 1052-1117 1202-1227 1302-1327 1412-1437 1512-1537 1612-1637 1717-1742 1807-1832 1907-1932 2007-2032 Vmt> Nm> 0.0270 0.0266 0.0263 0.0286 0.0284 0.0275 0.0278 0.0323 0.0289 0.0296 0.0298 0.0276 (std) (dscf) (0.952) (0.941) (0.930) (1.01) (1.002) (0.972) (0.982) (1.14) (1.022) (1.046) (1.053) (0.973) g/NrrP 0.072 0.051 0.091 0.062 0.061 0.087 0.075 0.067 0.062 0.088 0.095 0.088 (10* Ib/dscf) (0.045) (0.032) (0.057) (0.039) (0.038) (0.054) (0.047) (0.042) (0.039) (0.055) (0.059) (0.055) S02, ppm 27.4 19.2 34.5 23.7 23.2 32.8 29.2 25.6 24.0 33.6 36.2 33.7 ng/J 63.2 43.4 78.6 54.6 52.4 67.9 64.5 55.4 57.2 80.8 82.5 68.8 (ib soy 1fj6 Btu) (0. 147) (0.101) (0. 183) (0. 127) (0. 122) (0. 158) (0. 150) (0. 129) (0. 133) (0. 188) (0. 192) (0. 160) %02 14.6 14.4 14.5 14.5 14.5 13.9 14.2 14.2 14.9 14.9 14.6 13.9 S02, ppm 26.6 39.2 40.2 29.0 29.2 33.1 35.3 34.1 20.1 36.3 34.6 37.4 ng/J 56.7 72.6 103.6 78.2 61.5 67.0 83.8 64.5 44.3 71.3 81.7 83.4 (Ib SO2/ 1& Btu) (0. 132) (0. 169) (0.241) (0. 182) (0. 143) (0. 156) (0. 195) (0. 150) (0. 103) (0. 166) (0. 190) (0. 194) %02 13.7 12.6 12.8 15.2 13.6 13.3 12.7 12.8 13.9 13.1 14.4 14.0 a Emission results based on use of 0.001 b Vm — metered volume (dry basis). N barium perchlorate. Tab/a 4. 30-Day Summary of SO2 Concentrations and Scrubber Efficiency March-April 1981 Hours Date CEM Data March 4 March 5 March 6 March 7 March 8 March 9 March 10 March 1 1 March 12 March 14 March 15 March 20 March 21 March 22 March 24 March 25 March 26 March 27 March 28 March 29 March 30 April 2 April 3 April 4 April 5 April 6 April 7 April 8 April 9 April 10 Mean Maximum Minimum STD DEV % STD DEV 24 18 21 23 19 20 20 19 18 18 22 21 19 23 22 18 21 21 23 19 18 24 21 22 22 22 22 23 22 23 S02lnlet SO2 Outlet lb/1& Btu ng/J Ib /10ft Btu ng/J 4.00 3.10 4.11 3.82 4.16 4.17 4.88 4.37 4.45 6.19 5.21 4.95 5.22 4.64 5.48 4.97 6.15 4.85 4.52 6.43 5.38 4.83 5.07 4.79 5.27 5.15 5.40 5.50 6.16 5.06 4.94 6.43 3.10 0.75 15.2 1719.8 1332.9 1767.1 1642.4 1788.6 1792.9 2098.2 1878.9 1913.3 2661.4 2240. 1 2128.3 2244.4 1995.0 2356. 1 2136.9 2644.2 2085.3 1943.4 2764.6 2313. 1 2O76. 7 2179.9 2059.5 2265.9 2214.3 2321.7 2364. 7 2648.5 2175.6 2125.1 2764.6 1332.9 323.1 15.2 0.30 0.14 0.24 0.30 0.37 0.27 0.27 0.21 0.22 0.45 0.30 0.32 0.15 0.25 0.55 0.32 0.32 0.29 0.43 0.61 0.36 0.14 0.13 0.18 0.33 0.19 0.17 0.21 0.34 0.16 0.28 0.61 0.13 0.12 41.3 129.0 60.2 103.2 129.0 159.1 116.1 116.1 90.3 94.6 193.5 129.0 137.6 64.5 107.5 236.5 137.6 137.6 124.7 184.9 262.3 154.8 60.2 55.9 77.4 141.9 81.7 73.1 90.3 146.2 68.8 122.1 262.3 55.9 50.4 41.3 Eff % 92.5 95.5 94.2 92.1 91.1 93.5 94.5 95.2 95.1 92.7 94.2 93.5 97.1 94.6 90.0 93.6 94.8 94.0 90.5 90.5 93.3 97.1 97.4 96.2 93.7 96.3 96.9 96.2 94.5 96.8 94.3 97.4 90.0 2.1 2.2 ------- Table 5. Coal Composition8 (%, except as noted) 2/12 Sulfur 2.62 Carbon 73.06 Hydrogen 5.24 Oxygen 9.24 Nitrogen 1.58 Chlorine 0.19 Volatile matter 41.65 Fixed carbon 50.09 Ash 8.26 Heat value. kJ/kg 31,410 (Btu/lb) (13,500) Moisture 3.66 2/13 2/14 2.80 3.00 73.67 69.37 5.22 4.72 8.38 13.84 1.56 1.51 0.21 0.20 41.54 41.71 50.09 50.73 8.37 7.56 31,040 31,225 (13,340) (13,420) 3.57 3.81 2/1 6 2/1 7 1.62 2.51 76.23 74.71 5.11 5.26 7. 19 7.59 1.81 1.64 0.20 0. 18 37.47 38.61 54.49 53. JO 8.04 8.29 31,550 31,410 (13.560) (13,500) 3.70 2.34 Date 1981 2/24 3/2-6" 3/9-13" 3/16-20" 3/23-27" 1.64 2.86 3.55 2.85 2.70 74.29 71.48 72.19 74.98 72.61 5.30 5.37 5.19 5.37 3.64 9.06 7.76 7.72 7.83 11.77 1.74 1.54 1.56 1.65 1.54 0.14 0.18 0.12 0.16 0.09 37.18 38.99 39.08 40.82 40.01 54.85 50.20 51.25 52.02 52.34 7.97 10.81 9.67 7.16 7.65 31,690 30,250 30,510 31,620 31,010 (13,620)(13,000) (13,114) (13,590) (13,328) 2.02 8.62 7.92 9.35 6.99 3/30-4/3" 4/6-1 Of 2.73 2.22 74. 1 3 75.50 5.33 5.61 9.78 8.99 1.49 1.67 0.09 0. 12 40.58 40.93 52.97 53.18 6.45 5.89 31,240 32,470 (13.427) (13.955) 6.35 4.26 aDry basis except for moisture. ^Composite. Table 6. Adipic Acid, Limestone, and Coal Usage Date 11981) February 20 21 22 23 24 25 26 27 28 March 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 pril 1 2 3 Average adipic acid feed. kg/h (Ib/h)* 3.63 (8) 3.63 (8) 1.81 (4) 1.81 (4) 3.63 (8) 2. 72 (6) 6.35 (14) 2. 72 (6) 4.54 (10jc 5.44 (12)c 3.63 (8)c 4.54 (10)c 3.63 (8) 3.63 (8) 3.63 (8) 2.62 (6) 4.08 (9) 4.08 (9) 4.54 (10) 3.63 (8) 7.26 (16)' 4.54 (10) 7.26 (16)c 6.35 (14)c 1.81 (4)d 2. 72 (6) 3.63 (8) 4.54 (10) 3.63 (8) 4.54 (10) 4.54 (10) 3.63 (8) 2.27 (5)^ OfOJf 6.35 (14)c 5.44 (12) 3.63 (8) Average limestone feed. kg/h (Ib/hp 261 (575) 281 (619) 331 (729) 319 (702) 325 (716) 311 (686) 321 (707) 327 (720) 341 (752) 362 (798) 372 (820) 360 (793) 388 (854) 387 (853) 370 (814) 347 (765) 350 (771) 353 (778) 337 (742) 331 (728) 332 (731) 311 (686) 220 (489) 246 (542) 320 (704) 404 (890) 391 (861) 318 (700) 218(479) 236 (520) 298 (656) 285 (627) 270 (595) 262 (576) 213(468) 184 (405)<> 0(0)' 292 (644) 212(467) 198 (435) Mg (tons) of coal used/day 85.0 (77. 1) 90.3 (81.9) 92.7 (84.0) 112.1 (101.6) 126.6(114.8) 127.8(115.9) 113.4(102.8) 130.4(118.2) 113.5(102.9) 124.6 (113.0) 108.6(98.5) 106. 1 (96.2) 100.8(91.4) 112.6(102.1) 132.0(119.7) 131.4(119.1) 138. 1 (125.2) 123.1 (111.6) 121.1 (109.8) 99.9 (90.6) 94.6(85.8) 97.5(88.4) 102. 1 (92.6) 101.1 (91.7) 112.3(101.8) 133.2 (120.8) 118.5 (107.4) 136.4 (123. 7) 127.1 (115.2) 113.2(102.6) 99.2 (89.9) 103.2 (93.6) 98.8(89.6) 98.5 (89.3) 94.2 (85.4) 97.9(88.8) 95. 1 (86.2) 78.4(71.1) 69.4 (62.9) 79.9(72.4) 71. 1 (64.5) 76. 1 (69.0) 60.8(55.1) ------- Table 6. (continued) Date 11981) 4 5 6 7 8 9 10 Average adipic acid feed, kg/h (lb/h>» 3.63 (8) 1.81 (4)1 4.54 (10) 4.54 (10) 2. 72 (6) 2.72(6) 2.27 (5) • Average limestone feed, kg/h (Ib/hp 218(480) 239 (526) 276 (608) 225 (496) 207 (455) 203 (447) 212 (467) Mg (tons) of coal used/day 60.9 (55.2) 74.2 (67.3) 68.1 (61.7) 68.4 (62.0) 66.2 (60.O) 63.4 (57.5) 74.2 (67.3) "24-hour basis. t>Based on hours of feed. cAdipic acid was dumped in the thickener. ^Vibrator was turned off. Adipic acid feeder plugged. eScrubber was bypassed at 1940 because the thickener was adipic acid feeds were turned off at that time. 'The scrubber was still off-line. It was restarted before 8 a. m. plugged. Limestone and on April 1. P. A. Clarke, R. W. Gerstle, D. S. Henzel, K. W. Mason, andS. R. Sabatiniare with PEDCo Environmental, Inc., Cincinnati, OH 45246. J. David Mobley is the EPA Project Officer (see below). The complete report, entitled "The Adipic Acid Enhanced Flue Gas Desulfurization Process for Industrial Boilers: Volume 1. Field Test Results." (Order No. PB 83-144 774; Cost: $32.50. 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: Industrial Environmental Research Laboratory U.S. Environmental Protection Agency Research Triangle Park, NC 27711 United States Environmental Protection Agency Center for Environmental Research Information Cincinnati OH 45268 Postage and Fees Paid Environmental Protection Agency EPA 335 Official Business Penalty for Private Use $300 PS 0000329 AGENCV ------- |