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Research on treatment of odor gas containing hydrogen sulfide by multilayer biofilter
多层生物滤塔净化硫化氢废气研究

Zhang Huaxin,Li Shunyi,Yang Songbo,Ma Hongyan,Wang Yan,
张华新
,李顺义,杨松波,马红妍,王岩

环境工程学报 , 2011,
Abstract: Using sawdust as filler, biofiltration technique for treating H2S-contaminated gas streams was investigated. The suitable technological conditions and removal kinetics were studied. The results showed that the multilayer biofilter had a higher removal rate of H2S than that of the single layer biofilter. The removal rate of H2S was higher than 90% when the inlet volumetric loading rate of H2S was below 153.2 g H2S/(m3·d). When the inlet hydrogen sulfide was lower than 70 mg/m3, the bottom layer which was 200 mm thick removed more than 50% of the total H2S removal. The biofilter worked well as the moisture content ranged from 50% to 60%.The removal kinetics were researched based on the Michaelis-Menten model, two kinetic parameters were Ks with a value of 22.5 mg/m3 and Vm with a value of 1 000 g H2S/(m3·d).
Effects of Moisture content and pH on H2S Removal in a Biofilter
填料湿度、pH值对BF系统处理H2S废气的影响

WANG Jiade,GAO Zengliang,CHU Shuyi,CHEN Jianmeng,
王家德
,高增粱,褚淑祎,陈建孟

环境科学学报 , 2006,
Abstract: In order to optimize the design and operation of biofilters, effects of moisture content and pH on H2S removal in a biofiher have been studied in this paper. The experiment has reached following important results. The H2S removal efficiency in the biofiher decreased when the moisture content was below 45% and a proper moisture content ranging from 50% to 70% was essential to the biofilter for a long-term operation. The properties of the inlet gas such as gas velocity, relative humidity and temperature, interacted with the biological activities to change the moisture content in the biofiher, and under the conditions of this experiment, the maximum drying rate of packing was in proportion to the logarithm of relative humidity, 0.68 power of gas velocity and 0.8 power of temperature. Finally the effect of pH on the activity of H2S-oxided bacteria was obvious when the value of pH exceeded 8.0.
Study on packing biofilm and process conditions of hydrogen sulfide and ammonia removal by composite biofilter
复合生物滤池处理H2S和NH3的挂膜与工艺条件

Yu Guanghui,Xu Xiaojun,He Pinjing,
余光辉
,徐晓军,何品晶

环境工程学报 , 2007,
Abstract: The composite biofilter(a combination of biotrickling filter and biofilter),taking surfactant-modified clinoptilolite and wood chip as the media respectively,was applied to treat the mixed odors(H_2S and NH_3).The microbial acclimation and the process conditions were studied.The results indicated that the period of packing biofilm was 10~14 d with surfactant modification,which shortened 14~18 d,compared to the activated carbon used in literatures.The optimum height and recycle liquid rate of composite biofilter were 120 cm and 4.56 L/h,respectively.The biotrickling had better removal efficiency for hydrophilic NH_3 than biofilter,while the biofilter had better removal efficiency for hydrophobic H_2S than biotrickling filter.Therefore,the composite biofilter could be used to treat the mixed odors.
Experimental study on the treatment of odor gas containing hydrogen sulfide by peat biofilter
泥炭生物滤塔处理低浓度H2S气体的试验研究

YIN Jun,FANG Shi,CHEN Yingxu,
殷峻
,方士,陈英旭

环境科学学报 , 2003,
Abstract: Biofiltration technique for treating H 2S-contaminated gas streams was investigated. The effects of retention time and volumetric mass loading on H 2S removal efficiency, the ability of biofilter to buffer shock loading of the peat biofilter and removal kinetics were studied. The results showed that when the gas retention time was 30*!s, the H 2S removal efficiency was higher than 99%, and the reactor was robust enough to recover reasonably quickly in a shock loading scenario.
Numerical simulation for volatile organic compound removal in rotating drum biofilter
Hong Chen,ChunPing Yang,GuangMing Zeng,KongLiang Yu,Wei Qu,GuanLong Yu,Lei Meng
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0332-8
Abstract: Rotating drum biofilters (RDBs) could effectively remove volatile organic compounds (VOCs) from waste gas streams. A mathematical model was developed on the basis of mass transport and mass balance equations in an RDB, the two-film theory, and the Monod kinetics. This model took account of mass transfer and biodegradation of VOC in the gas-water-biofilm three-phase system in the biofilter, and could simulate variations of VOC removal efficiency with a changing specific surface area and porosity of the media due to the increasing of biofilm thickness in the biofilter. Toluene was used as a model VOC. This model was further simplified by introducing a coefficient of the gas velocity and neglecting the water phase due to the complexity of operating conditions. The equations for the biofilm phase, gas phase, and biofilm accumulation in this model were solved using colloction method, analytic method, and the Runge-Kutta method separately. A computer program was written down as MATLAB to solve this model. Results of numerical solutions showed that toluene removal efficiency in the RDB increased and reached the maximum values of 97% on day 4 after the startup, and then decreased the remained at 90% after 5 more days of operation. Toluene concentration was high at the outermost layer where more than 70% toluene was removed, and was low at the innermost layer where less than 10% toluene was removed. The dynamic removal efficiencies from this model correlated reasonably well with experimental results for toluene removal in a multi-layered RDB.
Moisture removal of paddy by agricultural residues: basic physical parameters and drying kinetics modeling
Tirawanichakul, Y.,Tirawanichakul, S.,Saniso, E.
Songklanakarin Journal of Science and Technology , 2007,
Abstract: The objectives of this research were to study basic physical parameters of three agricultural residues that could be used for prediction of paddy drying kinetics using desiccants, to investigate a suitable methodfor moisture reduction of fresh paddy using 3 absorbents, and to modify the drying model of Inoue et al. for determining the evolution of moisture transfer during the drying period. Rice husk, sago palm rachis andcoconut husk were used as moisture desiccants in these experiments. From the results, it was concluded that the apparent density of all adsorbents was a linear function of moisture content whilst an equilibriummoisture content equation following Hendersonís model gave the best fit to the experimental results. From studying the relationship between moisture ratio and drying time under the condition of drying temperaturesof 30, 50 and 70oC, air flow rate of 1.6 m/s and initial moisture content of absorbents of 15, 20 and 27% dry-basis, it was shown that the moisture ratio decreased when drying time increased. In addition, thethin-layer desiccant drying equation following of the Page model can appropriately explain the evolution of moisture content of paddy over the drying time. The diffusion coefficient of all absorbents, which was in therange of 1x10-8 to 6x10-8 m2/h, was relatively dependent on drying temperature and inversely related to drying time. The diffusivity of coconut husk had the highest value compared to the other absorbents.The simulating modified mathematical model to determine drying kinetics of paddy using absorption technique and the simulated results had good relation to the experimental results for all adsorbents.
Removal of styrene from waste gas stream using a biofilter  [cached]
B Bina,R Dehghanzadeh,H Pourmoghadas,A Kalantary
Journal of Research in Medical Sciences , 2004,
Abstract: Background: Styrene is produced in large quantities in the chemical industries and it has been listed among the 189 hazardous and toxic atmospheric contaminants under Clean Air Act Amendments, 1990, due to its adverse effects on human health. The biofiltration has been widely and efficiently applied during recent decades for the treatment of air streams contaminated by volatile organic compounds at low concentrations. Also this technology has been applied widely and efficiently in the removal of styrene from waste gas streams. Methods: Biofiltration of waste gas stream polluted by styrene vapor was investigated in a three-stage bench scale reactor. Yard waste compost using shredded hard plastics as a bulking agent in a 75:25 v/v mix of plastics:compost was used to packing biofilter. The system inoculation was achieved by adding thickened activated sludge obtained from municipal wastewater treatment plant and the effects of loading rate, inlet concentration, and empty bed retention time variations on the performance and operation of biofilter were studied. Results: Microbial acclimation to styrene was achieved with inlet concentration of 65 ± 11 ppm and bed contact time of 360 s after 57 days of operation. Under steady state conditions experimental results showed equal average removal efficiency of about 84% at loading rates of 60 and 80 g m-3 h-1 with empty bed retention time of 60 s. Maximum elimination capacity was obtained up to 81 g m-3 h-1 with organic loading rate of about 120 g m-3 h-1. Reduction in performance was observed at inlet concentrations of upper than 650 ppm related to organic loading rates up to 160 g m-3 h-1 and then removal efficiency was decreased sharply. Evaluation of the concentration profile along the bed height of column indicated that the most value of elimination capacity occurred in the first section of biofilter. Elimination capacity also showed higher performance when empty bed retention time was reduced to 30 s. Conclusion: Microbial acclimation period for biofiltration of styrene inoculated with activated sludge was longer than inoculation with adapted or enriched bacteria. Addition of compost improved performance of the biofilter because of high water retention capacity. Also high pollutant load with significant concentration to the first sections has a clear inhibitative effect on biofilter performance along the bed height of biofilter. Keywords: biofilter, styrene, Volatile Organic Compounds (VOCs), waste gas, compost.
Evaluation of Stormwater Biofilter Media for Escherichia coli Removal in a Laboratory Microcosm
Gregory T. Kleinheinz, Tabitha Zehms and Kathryn Koenig
Air, Soil and Water Research , 2012,
Abstract: Recreational water sites such as beaches along lakes, rivers, or oceans, are one of the most popular activities in many parts of the world. Recently rainfall and runoff due to rainfall events has been associated with increasing microbial levels in recreational water. This runoff can lead to beach closures and potentially unsanitary conditions at popular swimming beaches. The impact of stormwater on beach water quality has led to a myriad of option for controlling stormwater. Some of these include grass buffer partitions, stormwater detention basins, media filters, catch basin inserts, and infiltration units. Biofilters, or infiltration units are gaining popularity as a treatment option for stormwater around the Great Lakes basin, but we are aware of no studies that have looked at the indicator organism (i.e. Escherichia coli, or E.coli) removal potential of these infiltration units and the media used in them. The overall objective of this study was to evaluate the performance of a stormwater biofilter medium in removing the indicator organism E.coli in a laboratory system. When several laboratory biofilter system were challenged with E.coli concentrations of 2.82E3 and 2.85E5 E.coli/100mL of simulated stormwater in a 1.25 cm rain event, the systems were able to remove between 83 and 100% of the E.coli in this influent. During a subsequent 1.25 cm rain event with E.coli-free water, the biofilter was able to retain 68%–100% of the E.coli originally inoculated into the system. The results of this study indicate that these systems hold promise for mitigation of E.coli from storm water near recreational beaches. These findings will assist beach managers, engineers, and municipal stake holders evaluate the usefulness of biofilter infiltration as a storm water management tool in order to decrease E.coli input into beach areas.
Evaluation of Stormwater Biofilter Media for Escherichia coli Removal in a Laboratory Microcosm
Gregory T. Kleinheinz,Tabitha Zehms,Kathryn Koenig
Air, Soil and Water Research , 2008,
Abstract: Recreational water sites such as beaches along lakes, rivers, or oceans, are one of the most popular activities in many parts of the world. Recently rainfall and runoff due to rainfall events has been associated with increasing microbial levels in recreational water. This runoff can lead to beach closures and potentially unsanitary conditions at popular swimming beaches. The impact of stormwater on beach water quality has led to a myriad of option for controlling stormwater. Some of these include grass buffer partitions, stormwater detention basins, media filters, catch basin inserts, and infiltration units. Biofilters, or infiltration units are gaining popularity as a treatment option for stormwater around the Great Lakes basin, but we are aware of no studies that have looked at the indicator organism (i.e. Escherichia coli, or E.coli) removal potential of these infiltration units and the media used in them. The overall objective of this study was to evaluate the performance of a stormwater biofilter medium in removing the indicator organism E.coli in a laboratory system. When several laboratory biofilter system were challenged with E.coli concentrations of 2.82E3 and 2.85E5 E.coli/100mL of simulated stormwater in a 1.25 cm rain event, the systems were able to remove between 83 and 100% of the E.coli in this influent. During a subsequent 1.25 cm rain event with E.coli-free water, the biofilter was able to retain 68%–100% of the E.coli originally inoculated into the system. The results of this study indicate that these systems hold promise for mitigation of E.coli from storm water near recreational beaches. These findings will assist beach managers, engineers, and municipal stake holders evaluate the usefulness of biofilter infiltration as a storm water management tool in order to decrease E.coli input into beach areas.
Isolates identification and characteristics of microorganisms in biotrickling filter and biofilter system treating H2S and NH3
YU Guang-hui,XU Xiao-jun,HE Pin-jing,
YU Guang-hui
,XU Xiao-jun,HE Pin-jing

环境科学学报(英文版) , 2007,
Abstract: A combination system of biotrickling filter (BTF) and biofilter (BF), adopting surfactant-modified clinoptilolite and surfactant-modified wood chip as the media respectively, was applied to treat H2S and NH3 simultaneously. The identification and sole carbon sources utilization patterns of isolates in the combination system were studied by Biolog system. The isolates were identified as Bacillus sphaericus, Geobacillus themoglucosidasius (55 degrees C) and Micrococcus luteus (ATCC 9341) in BTF, and Aspergillus sydowii (Bainier & Sartory) Thorm & Church in BF. Among 95 substrate classes supplied by Biolog system, the carboxylic acids and methyl esters had the highest utilization extent for the four species, followed by the amino acids and peptides. The descending sequence of carbon sources utilization capability of isolates was A. sydowii (52.6%), M. luteus (39.5%), B. sphaericus (21.6%), and G. thermoglucosidasius (17.7%).
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