固废处理行业臭气治理技术及其应用

臭气的产生机理为固废与氧气相互作用在好氧或厌氧菌的影响下,其中的有机成分衍生出刺激性气味或分解形成氧化物质。固废处理行业臭气成分主要包括含硫(S)臭气、含氮(N)臭气、卤代烃、烃类化合物、含氧(O)臭气等。臭气治理技术主要有活性炭吸附技术、离子除臭技术、生物除臭技术、植物液除臭技术。应用时应考虑费用、操作、投资与实际情况的匹配程度进行技术的选择。     

城市恶臭污染环境影响

随着工业的发展和城市化进程的加快,城市恶臭污染影响日趋严重。目前,城市主要恶臭污染源包括城镇污水厂、生活垃圾填埋场以及化工、炼油等工业排放源,生活污染源对居住环境的影响也不容忽视。为切实改善城市居民生活环境质量,政府及管理部门应加快建立完善的恶臭环境标准体系,从管理层面、技术改进及公众监督三个方面共同促进我国环境空气质量与城市居住环境质量的改善。     

某生活垃圾卫生填埋场填埋作业区覆膜抽气除臭试验研究

本文采用三种不同的覆膜抽气模式对填埋场作业面进行除臭试验研究,结果表明:覆膜1.0mm+3台负压车、2条负压管比单层覆膜0.3mm+1台负压抽气车、2条临负压管或覆膜0.3mm+3台负压车对氨气、硫化氢和臭气浓度的去除效果都要更好;但覆膜抽气法对总挥发性有机物(Total Volatile Organic Compounds,TVOC)的去除效果较之前更差,这主要是由于TVOC主要为分子量较大的有机物,扩散较慢,且垃圾堆体在厌氧条件下产生的TVOC浓度更高。     

碱渣处理装置的现状与展望

碱渣处理一直是困扰炼厂环境保护的一大难题。碱渣处理装置成为炼厂的主要恶臭污染源，亟需处理。为此，我们通过国内外技术交流，在文献调研基础上，提出了碱渣空气氧化预处理脱臭治理方案。该工艺成熟、简单、可靠，已用于国外一些炼厂，并可大大改善大气污染，提高回收副产品的质量。     

微生物过滤法净化恶臭污染物

分析了处理恶臭污染物的吸附法、化学吸收法、催化燃烧法、生物处理法等优缺点 ,并介绍了微生物过滤器法净化恶臭物质的过程及工艺实例。     

Determination of urine-derived odorous compounds in a source separation sanitation system

Source separation sanitation systems have attracted more and more attention recently.However, separate urine collection and treatment could induce odor issues, especially in large scale application. In order to avoid such issues, it is necessary to monitor the odor related compounds that might be generated during urine storage. This study investigated the odorous compounds that emitted from source-separated human urine under different hydrolysis conditions. Batch experiments were conducted to investigate the effect of temperature, stale/fresh urine ratio and urine dilution on odor emissions. It was found that ammonia, dimethyl disulfide, allyl methyl sulfide and 4-heptanone were the main odorous compounds generated from human urine, with headspace concentrations hundreds of times higher than their respective odor thresholds. Furthermore, the high temperature accelerated urine hydrolysis and liquid–gas mass transfer, resulting a remarkable increase of odor emissions from the urine solution. The addition of stale urine enhanced urine hydrolysis and expedited odor emissions. On the contrary, diluted urine emitted less odorous compounds ascribed to reduced concentrations of odorant precursors. In addition,this study quantified the odor emissions and revealed the constraints of urine source separation in real-world applications. To address the odor issue, several control strategies are recommended for odor mitigation or elimination from an engineering perspective.     

Ecological niche and in-situ control of MIB producers in source water

Odor problems in source water caused by 2-methylisoborneol (MIB) have been a common issue in China recently, posing a high risk to drinking water safety. The earthy-musty odorant MIB has an extremely low odor threshold (4–16 ng/L) and is hard to remove via conventional processes in drinking water plants (DWP), and therefore could easily provoke complaints from consumers. This compound is produced by a group of filamentous cyanobacteria, mainly belonging to Oscillatoriales. Different from the well-studied surface-blooming Microcystis, filamentous cyanobacteria have specific niche characteristics that allow them to stay at a subsurface or deep layer in the water column. The underwater bloom of these MIB producers is therefore passively determined by the underwater light availability, which is governed by the cell density of surface scum. This suggests that drinking water reservoirs with relatively low nutrient contents are not able to support surface blooms, but are a fairly good fit to the specialized ecological niche of filamentous cyanobacteria; this could explain the widespread odor problems in source water. At present, MIB is mainly treated in DWP using advanced treatment processes and/or activated carbon, but these post-treatment methods have high cost, and not able to deal with water containing high MIB concentrations. Thus, in situ control of MIB producers in source water is an effective complement and is desirable. Lowering the underwater light availability is a possible measure to control MIB producers according to their niche characteristics, which can be obtained by either changing the water level or other measures.     

污水处理厂除臭工艺选择及工程设计

随着无锡市城北污水处理厂二期工程的扩建,污水处理厂除臭问题日益突出.针对目前常用的化学、活性炭吸附、氧离子基团、燃烧、纯天然植物提取液喷洒和生物等6种除臭方法,重点说明了除臭工艺的选择及除臭系统的工程设计,最后结合运行情况总结了除臭系统的设计特点.     

Simultaneous removal of hydrogen sulfide and volatile organic sulfur compounds in off-gas mixture from a wastewater treatment plant using a two-stage bio-trickling filter system

A two-stage BTF system was established treating odorous off-gas mixture from a WWTP. The two-stage BTF system showed resistance for the lifting load of H₂S and VOSC. Miseq Illumina sequencing showed separated functional microbial community in BTFs. Avoiding H₂S inhibition and enhancement of VOSC degradation was achieved. Key control point was discussed to help industrial application of the system. Simultaneous removal of hydrogen sulfide (H₂S) and volatile organic sulfur compounds (VOSCs) in off-gas mixture from a wastewater treatment plant (WWTP) is difficult due to the occasional inhibitory effects of H₂S on VOSC degradation. In this study, a two-stage bio-trickling filter (BTF) system was developed to treat off-gas mixture from a real WWTP facility. At an empty bed retention time of 40 s, removal efficiencies of H₂S, methanethiol, dimethyl sulfide, and dimethyl disulfide were 90.1, 88.4, 85.8, and 61.8%, respectively. Furthermore, the effect of lifting load shock on system performance was investigated and results indicated that removal of both H₂S and VOSCs was slightly affected. Illumina Miseq sequencing revealed that the microbial community of first-stage BTF contained high abundance of H₂S-affinity genera including Acidithiobacillus (51.43%), Metallibacterium (25.35%), and Thionomas (8.08%). Analysis of mechanism demonstrated that first stage of BTF removed 86.1% of H₂S, mitigating the suppression on VOSC degradation in second stage of BTF. Overall, the two-stage BTF system, an innovative bioprocess, can simultaneously remove H₂S and VOSC.     

三点比较式臭袋法测定环境中臭气浓度

就三点比较式臭袋法在测定环境空气臭气浓度时应注意的现场踏勘、采样点的选择、采样次数、配气、嗅辨过程,以及臭气浓度计算等问题进行探讨,使该方法更加完善、简便.