United States Environmental Protection Agency Hazardous Waste Engineering Research Laboratory Cincinnati OH 45268 Research and Development EPA/600/S2-85/120 Dec 1985 SrEPA Project Summary Evaluation of Fabric Filter Performance at Ames Solid Waste Recovery System F. D. Hall, J. M. Bruck, and D. N. Albrinck EPA conducted a 36-month study to measure air pollution emissions and to evaluate control technologies for waste- as-fuel processes. One of the processes studied was the resource recovery plant operated by the municipal Department of Public Works of Ames. Iowa, which processes municipal solid waste. A fabric filter was used to control dust from the shredders, air density separa- tion (ADS), and conveyor transfer points. The fabric filter has operated successfuly since 1978 with a notice- able reduction in in-plant air dust concentrations. The major output of the Ames re- source recovery plant is refuse-derived fuel (RDF), which is transported to an adjacent power plant for burning and subsequent generation of power. This Project Summary was developed by EPA's Hazardous Waste Engineering Research Laboratory, Cincinnati, OH, 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). Background Particulate concentrations in the inlet and outlet gas streams of the fabric filter operating at the Ames resource recovery facility were tested to determine panic- ulate collection efficiency of the fabric filter and to quantify inlet and outlet paniculate concentrations. Over a 2-day test period, four simul- taneous inlet-outlet test runs were completed. Inlet samples were obtained by EPA Method 5. Outlet samples were obtained by simultaneously traversing the "open-air" top of the fabric filter with two high-volume (hi-vol) samplers, along two separate straight traverses. The particulate concentrations found along each outlet traverse were averaged to obtain the outlet particulate concentration for each run. The full report includes four appendices which give detailed information about the testing. Appendix A provides the specifi- cations of the fabric filter unit. Appendix B discusses the sampling and analytical methodology. Appendix C consists of computerized data calculations for inlet sampling conditions and hand-completed data sheets for outlet sampling. Appendix D describes the quality assurance pro- cedures. Results Table 1 summarizes the fabric filter performance. Calculations of average inlet and outlet particulate concentrations were based only on the values from the first three test runs because of a sampling error during Test Run B-4. The outlet concentration measured during Test Run B-4 is reported as an individual value; because there is no corresponding inlet value, it is not used in calculating the efficiency of collection. Excluding Test Run B-4, the average particulate removal efficiency was 97.8 percent. The results of inlet particulate sampling are shown in Table 2. The results of Test Run B-4 were not considered in the final evaluation because of an unreasonably high moisture content. Excluding Test Run B-4, inlet particulate concentration averaged 446 mg/dry standard m3, with a range from 259 to 748 mg/dry standard ------- m3. The corresponding participate mass flow rate averaged 32.3 kg/h and ranged from 19.5 to 52.6 kg/h. The results of outlet paniculate sam- pling are shown in Table 3. Each outlet test run is composed of two sample traverses, right and left. The final evalu- ation of performance is based on an average of the right and left traverse for each run For all test runs, outlet panic- ulate concentration averaged 11.9 mg/ dry standard m3, with a range from 8.63 to 18.6 mg/dry standard m3. The average paniculate emission rate from the fabric filter was 0 878 kg/h, with a range from 0.588 to 1.36 kg/h. Conclusions and Recommendations Results indicate that the fabric filter effectively controls particulates generated by various sources in the Ames resource recovery plant. The fabric filter was tested and evaluated under normal operating Table 1. Summary of Fabric Filter Performance Test Run No. B-1 B-2 B-3 B-4 A verage Inlet Paniculate Concentration, mg/dry std. m3 748 259 331 b 446" Outlet P articulate Concentration," mg/dry std m3 11.4 8.63 9.16 18.6 3.73d Paniculate Removal Efficiency % 985 967 97.2 c 97.8" "Average of two outlet samples per run. ''Inaccurate value because of sampling error "Not calculated because of sampling error aNot including Test Run B-4. conditions; no attempt was made to optimize the operation or collection effi- ciency of the unit. Although the data show that the fabric filter at the Ames plant functions effec- tively, some improvements can be made. Bag shaking, a medium-energy cleaning mechanism, is currently used to remove dust that is prone to bridging and difficult to clean from the bags, and clogged bags remain a problem at the Ames plant Use of a high-energy cleaning mechanism (such as air pulsing) might solve the problem, but such a mechanism must be implemented in the design phase of an installation. This solution might increase power consumption and shorten bag life, but it would decrease maintenance time. The dust collection hoppers contributed to bag clogging, especially around the perimeter of each section of bags The location of the baghouse requires rela- tively shallow hopper side angles, which sometimes prevent dust from flowing freely from bags to hopper where the hopper side is very near the bottom of the bag Steeper side angles would alleviate the problem. Table 2. Inlet Paniculate Data* Test Average Run Temperature No at Inlet, °R B-1 B-2 B-3 B-4 555 557 557 558 Actual Volume of Volume of Gas Gas Sampled, Sampled at Standard m3 (ft3/ Conditions, m3 (ft3) 0.984(34.76) 1 1 1 13 .15 09 (39.95) (40.46) (38 44) 0.942 (33.3) 1 06 1.07 1.03 (37.6) (379) (36.4) Total Paniculate Paniculate. Concentration, mg mg/dry std, m3 704.6 275.0 353.9 731.2 748 259 331 710 "For all test runs, the barometric pressure was 760 0 mm (29.92 in.) Hg, the stack pressure was 766.6 mm (30.18 in.) Hg, and the sampling time was 48 min Table 3. Outlet Paniculate Data3 Test Run No" B-1R B-1L B-2R B-2L B-3R B-3L B-4R B-4L Average AW,C cm (in ) HZ0 12 7 (5.0) 10.4(4 1) 16.0(6.3) 15.5 (6 1) 185(73) 21.8(86) 19.1 (7.5) 23.6 (93) A verage Temperature at Outlet, °R 557 557 555 555 550 550 554 554 Samp/ing Flow Rate, m3/min (acfm) 1 07 (37.9) 0.977 (34 5) 121 (42.7) 1 19 (41.9) 131 (464) 1 45 (51 2) 1 33 (47 1) 152 (538) Sampling Time, min 48 40 48 45 48 45 48 45 Volume of Gas Sampled at Standard Conditions, m3 (ft3) 48.7(1720) 37.1 (1310) 55.2(1950) 50.7(1790) 606(2140) 62.6(2210) 61.2(2160) 65.4(2310) Total Particu/ates, mg 451.4 501.5 362.2 542.5 695.0 4263 1292.3 10525 Paniculate Concentration, mg/dry std. m3 9.27 13.5 6.56 10.7 11.5 6.81 21 1 16.1 "For all test runs, the barometric pressure was 760 0 mm (29.92 in.) Hg. DR designates right traverse and L designates left traverse. cSee Figure 4-1 in the full report ------- F. D. Hall, J. M. Bruck, and D. N. Albrinck are with PEDCo Environmental, Inc., Cincinnati. OH 45246. Robert A. Olexsey and Michael Black are the EPA Project Officers (see below). The complete report, entitled "Evaluation of Fabric Filter Performance at Ames Solid Waste Recovery System," (Order No. PB 86-110 933/AS; Cost: $9.95, 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 Officers can be contacted at: Hazardous Waste Engineering Research Laboratory U.S. Environmental Protection Agency Cincinnati, OH 45268 United States Environmental Protection Agency Center for Environmental Research Information Cincinnati OH 45268 Official Business Penalty for Private Use $300 EPA/600/S2-85/120 GQOC329 PS ------- |