生物脱臭技术的现状与展望

生物脱臭技术是利用固定在载体上的微生物，分解H2S、NH3、有机溶剂等有害、发臭气体，使之成为无害、无味气体，从而达到除臭的目的。生物脱臭法与活性炭吸附、药液吸收等物理化学脱臭法相比，具有维护管理简单、运行成本低等优点。指出生物脱臭技术是一种应用前景广泛的除臭技术。     

污水除臭技术的应用及研究现状

近年来城市污水处理设施数量不断增加,由此产生的臭气污染严重影响了环境空气质量,并严重损害了城市居民健康。污水脱臭问题引起广泛关注。通过介绍除臭技术在污水处理厂的实际应用,分析了常用除臭技术的优缺点和适用条件,阐述了目前低温等离子体法及纳米材料净化法等除臭新技术的研究现状,同时对除臭技术发展趋势进行展望,为实际工程应用提供指导。     

污水处理厂几种除臭技术的效果比较

重点介绍了污水处理厂运行过程中产生臭气的消除方法，以及采用土壤脱臭、化学反应除臭、生物／活性炭脱臭和高能离子脱臭的作用原理、工艺流程及设计参数，并举出了具体的工程实例。     

城镇污水处理厂生物除臭技术的关键影响因素及案例分析

城镇污水处理厂运行中产生恶臭气体并因此导致空气污染的问题日益严重.生物除臭技术具有操作简便、运行成本低、二次污染小等优点,适用于污水处理厂恶臭气体的处理.阐述了污水处理厂臭气的主要成分、浓度及分布特点,分析了生物除臭技术的4个关键影响因素(微生物、营养液、pH和填料),并结合影响因素剖析了3个工程应用典型案例,总结了生...     

污水厂生物除臭设施运行及影响因素的研究

在污水处理过程中会有大量的恶臭气体产生,主要含硫化氢和氨等发臭物质.这些臭味物质逸散到空气中,对污水处理厂及其周边的空气环境造成危害.针对清河污水处理厂原有生物除臭设施除臭效率难以提高的问题,对气体收集系统和生物除臭滤池内的喷淋管路进行了改造,并更换了新型生物填料.本研究对改造前后的除臭效果进行了考察,结果显示,硫化氢的平均去除率从改造前的36.5%提高到62.9%,最大去除率可以达到96.2%;氨的去除率从28.2%提高到接近100%.臭味气体的处理效果随除臭滤池的温度、气体的相对湿度的升高而提高.为此,对臭味气体的负荷、流量、温度以及湿度等因素进行了研究,在温度＞20℃、相对湿度＞80%的条件下,生物除臭滤池能够有比较理想的处理效果.     

逆流式和错流式生物滴滤装置脱臭性能研究

采用逆流式生物滴滤塔(DBTF)和错流式生物滴滤装置(CBTF)处理含氨和三甲胺的恶臭气体,研究生物脱臭性能。研究结果表明,逆流式和错流式生物滴滤装置都能有效地去除含氮混合恶臭气体,对氨和三甲胺的净化效率可达99.4%以上。逆流式和错流式生物脱臭装置具有较好的抗冲击负荷,运行稳定。DBTF和CBTF的适宜工艺操作条件为:氨进气负荷分别为26 g/(m3.h)和24.6 g/(m3.h),三甲胺进气负荷都为113 g/(m3.h);停留时间分别为29.1 s和32 s,喷淋量分别为37 mL/min和51.5 mL/min,循环液pH值范围都是6.3~7.0。这为生物脱臭技术工程推广应用和产业化应用奠定基础。     

污水处理中的恶臭对周边环境的污染及其治理

就污水处理厂运行过程中产生的臭气对周边环境产生的污染情况,针对臭气的治理方法,重点介绍了物理脱臭法、化学脱臭法、生物脱臭法的作用原理、工艺流程及设计参数。     

城市污水处理厂除臭生物滤池运行效果及影响因素研究

对山东某城市污水处理厂散发的恶臭气体进行除臭研究,考察了除臭生物滤池的运行效果、工艺影响因素和除臭生物滤池内微生物相特点。结果表明:(1)在进气量为828 m3/h、气体停留时间为30 s、硫化氢和氨进气质量浓度分别为0.5~28.4、0.9~34.3 mg/m3的条件下,稳定运行时,大部分时间硫化氢和氨去除率分别达98%和80%以上,而且除臭生物滤池对于进气负荷具有较强的抗冲击能力。(2)当填料含湿量为43.6%~63.4%时,硫化氢去除率在90%以上;氨去除受填料含湿量的影响较大,填料含湿量越高越利于氨的去除。(3)在处理低浓度含硫化氢和氨的恶臭气体时,生物除臭工程可以在低填料pH(3.0左右)下长期运行,并保持较高的恶臭气体去除率。(4)运行第60天后,当温度为10℃以上时,硫化氢和氨去除率几乎不受影响;第169天后,当温度降至10℃以下时,硫化氢和氨去除率均有一定程度的下降,最低分别为94.6%和79.8%。(5)除臭生物滤池稳定运行时,优势硫氧化菌主要为嗜酸性硫细菌。     

生物法降解养殖场臭气中H_2S的反应器启动

畜禽养殖场臭气成分复杂,完全去除较为困难。生物法是目前应用较广泛的脱臭方法,其中能否将生物膜附着在填料上是影响生物法去除恶臭气体效率的重要因素。本实验采用定时定量投加Na2S的方式驯化活性污泥,并选用MLSS浓度和SO42-浓度增量变化2个指标作为污泥驯化成熟的指标,比传统的以MLSS作为污泥驯化成熟的指标更准确。采用循环污泥的挂膜方式,运行2 d后,通入新鲜的空气和H2S气体,2周后反应器启动成功。     

生物法降解养殖场臭气中H2S的反应器启动

畜禽养殖场臭气成分复杂,完全去除较为困难。生物法是目前应用较广泛的脱臭方法,其中能否将生物膜附着在填料上是影响生物法去除恶臭气体效率的重要因素。本实验采用定时定量投加Na2S的方式驯化活性污泥,并选用MLSS浓度和SO42-浓度增量变化2个指标作为污泥驯化成熟的指标,比传统的以MLSS作为污泥驯化成熟的指标更准确。采用循环污泥的挂膜方式,运行2 d后,通入新鲜的空气和H2S气体,2周后反应器启动成功。     

生物滴滤器处理味精厂挥发性恶臭废气的试验研究

报道了采用以沸石为填料的生物滴滤器净化处理味精厂内挥发性恶臭废气的试验结果。在一定的试验条件下,当高强度恶臭废气的进气量<3.0m3/h时,系统除臭效果显著,这为净化以味精厂内恶臭废气为代表的多组分复杂气体提供了切实可行的新技术,具有很好的市场应用前景。此外,研究表明,在净化氨氮臭气取得良好效果的生物膜基础之上,加入特定菌液能较快地培养出适宜处理味精厂内恶臭废气的微生物种群,且能获得满意的净化效果。     

On the Determination of Odor Thresholds in Air Pollution Control—An Experimental Field Study on Flue Gases from Sulfate Cellulose Plants

From the hygienic point of view, not only the health hazards caused by air pollutants but also the odor from emitted flue gases should be reduced to a minimum. An effective control of the risk of odor at ground level presupposes knowledge of the source concentration of the odoriferous gas as well as its odor threshold. This threshold has to be estimated empirically, as the flue gases often contain a complex mixture of different odoriferous substances, the odor thresholds of which are in most cases unknown. For this purpose a method has been developed for estimating the odor thresholds of flue gases emitted, from different industrial processes. The method, afield method, is based on an exposure procedure, a number of subjects compare different concentrations of the flue gas with samples of fresh air and decide at what concentration the flue gas is no longer noticeable. The gas samples used are neither compressed, nor absorbed or heated before the exposure test. The method has been used in two studies on gases from Swedish sulfate cellulose plants. In order to estimate the effect on the odor threshold of different deodorizing measures, gas samples were taken not only from the stack but also from different phases in the production process. The results and a brief discussion on the practical applications of the method are given.     

Removal of hydrogen sulfide and sulfur dioxide by carbons impregnated with triethylenediamine

Activated carbon (AC) adsorption has long been considered to be a readily available technology for providing protection against exposure to acutely toxic gases. However, ACs without chemical impregnation have proven to be much less efficient than impregnated ACs in terms of gas removal. The impregnated ACs in current use are usually modified with metalloid impregnation agents (ASC-carbons; copper, chromium, or silver) to simultaneously enhance the chemical and physical properties of the ACs in removing specific poisonous gases. These metalloid agents, however, can cause acute poisoning to both humans and the environment, thereby necessitating the search for organic impregnation agents that present a much lower risk. The aim of the study reported here was to assess AC or ASC-carbon impregnated with triethylenediamine (TEDA) in terms of its adsorption capability for simulated hydrogen sulfide (H2S) and sulfur dioxide (SO2) gases. The investigation was undergone in a properly designed laboratory-scale and industrial fume hood evaluation. Using the system reported here, we obtained a significant adsorption: the removal capability for H2S and SO2 was 375 and 229 mg/g-C, respectively. BET measurements, element analysis, scanning electron microscopy, and energy dispersive spectrometry identified the removal mechanism for TEDA-impregnated AC to be both chemical and physical adsorption. Chemical adsorption and oxidation were the primary means by which TEDA-impregnated ASC-carbons removed the simulated gases.     

Index

Abstract

Activated carbon (AC) adsorption has long been considered to be a readily available technology for providing protection against exposure to acutely toxic gases. However, ACs without chemical impregnation have proven to be much less efficient than impregnated ACs in terms of gas removal. The impregnated ACs in current use are usually modified with metalloid impregnation agents (ASC-carbons; copper, chromium, or silver) to simultaneously enhance the chemical and physical properties of the ACs in removing specific poisonous gases. These metalloid agents, however, can cause acute poisoning to both humans and the environment, thereby necessitating the search for organic impregnation agents that present a much lower risk. The aim of the study reported here was to assess AC or ASC-carbon impregnated with triethylenediamine (TEDA) in terms of its adsorption capability for simulated hydrogen sulfide (H₂S) and sulfur dioxide (SO₂) gases. The investigation was undergone in a properly designed laboratory-scale and industrial fume hood evaluation. Using the system reported here, we obtained a significant adsorption: the removal capability for H₂S and SO₂ was 375 and 229 mg/g-C, respectively. BET measurements, element analysis, scanning electron microscopy, and energy dispersive spectrometry identified the removal mechanism for TEDA-impregnated AC to be both chemical and physical adsorption. Chemical adsorption and oxidation were the primary means by which TEDA-im pregnated ASC-carbons removed the simulated gases.     

Characteristic analysis for odor gas emitted from food waste anaerobic fermentation in the pretreatment workshop

Gas chromatography–mass spectrometry, olfactometry, and other related methods were applied for the qualitative and quantitative analysis of the characteristics of odorous gases in the pretreatment workshop. The composition of odorous gases emitted from municipal food waste was also investigated in this study. The results showed that the tested gases are mainly composed of aromatic gases, which account for 49% of the total volatile organic compounds (VOC) concentrations. The nitrogenous compounds comprise 15% of the total concentration and the other gases comprise the remaining 36%. The level of odor concentration ranged from 2523 odor units (OU) m^?3 to 3577 OU m^?3. The variation of the total chemical composition ranged from 19,725 µg m^?3 to 24,184 µg m^?3. Among the selected four sampling points, the discharge outlet was detected to have the highest concentration in terms of odor, total chemical, sulfur compounds, and aromatics. The correlation analysis showed that the odor concentrations were evidently related to the total chemical composition, sulfur compounds, and aromatics (P < 0.05, n = 5). The odor activity value analysis identified the top three compounds, hydrogen sulfide (91.8), ethyl sulfide (35.8), and trimethylamine (70.6), which contribute to air pollution complaint of waste materials.

Implications: Currently, the amount of food waste has rapidly increased, which leads to difficulty in waste management and more odorous gases released as air pollution. In processing of food wastes by anaerobic fermentation, odorous gases are generated, which significantly affect the workers and occupants in the plant. In the pretreatment workshop for anaerobic decomposition, the odorous gases are generated because of the stacking and decomposition of food wastes. The gases emitted mainly consist of organic gases because the food wastes are mainly organic materials. The other odors that comprise 1% of the gases are S-compounds, aromatics, esters, alkanes, and limonene, which result in unpleasant odors that are harmful to the health.     

一株高效脱硫脱氨氮菌的分离、鉴定及系统发育分析

从运行稳定的能同步脱臭的曝气生物滤池中采集样品,富集分离获得一株能高效脱硫脱氨氮的菌株TS-1。对分离菌株进行形态观察、生理生化试验及16S rRNA基因序列分析,结果表明,该菌株TS-1为革兰氏阳性菌,杆状;菌落在营养琼脂培养基上呈圆形,表面光滑,乳白色半透明;V-P试验阴性,能水解淀粉和明胶,利用柠檬酸盐生长;对菌株进行16S rRNA的PCR扩增,扩增产物测序结果表明分离菌株TS-1与巨大芽孢杆菌（Bacillus megaterium）同源性达到99%;以16S rRNA同源性为基础构建了包括24株相关种属细菌在内的系统发育树,在系统发育树中,分离菌株TS1与Bacillus megaterium在同一分支。结合形态观察、生理生化试验及16S rRNA基因序列分析结果,将其初步鉴定为巨大芽孢杆菌（Bacillus megaterium）。在常温（30±2）℃、转速为150 r/min的条件下,处理pH 7、S^2-和NH⁺₄-N分别为80 mg/L和88 mg/L的水样40 h,硫化物和氨氮的脱除率分别为91.8%和96.6%。     

生物焦炭滴滤塔降解苯乙烯废气的中试启动研究

苯乙烯废气既是一种挥发性有机化合物(VOCs),又属于我国恶臭气体控制的范围之内。其作为一种化工原料和有机溶剂广泛应用于工业生产中。生物法处理有机废气具有运行费用低和没有二次污染等优点。采用焦炭填料滴滤塔对苯乙烯废气的处理进行了中试启动研究。启动过程中,进气浓度范围是50~114 mg/m3,去除率为30%~45%左右,最高可达90%左右。所采用的焦炭填料可以认为是一种环境友好型填料,废弃后可作为燃料,值得推广。     

硝基芳香烃废水处理技术研究进展

本文综述了硝基芳香烃废水处理技术的研究现状及在实际工程中的应用现状 ,这些技术的原理主要基于物理、化学、生物等方面的作用。同时本文还展望了此类废水处理技术的应用前景 ,采用生物处理及其他多种处理方法协同作用已成为发展趋势。     

Impact of air pollution on outdoor cultural heritage objects and decoding the role of particulate matter: a critical review

Environmental Science and Pollution Research - Atmospheric gases and particulate matter (PM) in contact with the material’s surface lead to chemical and physical changes, which in most cases...     

城市危险化学品事故统计分析与对策

通过对2002-2004年发生在中国内地12个主要城市的435起非爆炸品类危险化学品事故统计分析,发现:(1)危险化学品事故总体呈进一步发展趋势;(2)处于城市生活区的化工企业发生危险化学品事故对城市的影响最大;(3)危险化学品在运输阶段,发生事故的比例最高;(4)民用燃气是造成使用阶段危险化学品事故的主要危险源,而人为失误和违规操作是民用燃气类危险化学品事故的主要原因.在统计分析基础上提出了相应的对策.