污泥直接干化产生的恶臭及挥发性有机物特征研究

利用水泥窑高温的特性协同处置城市污水厂污泥,无害化处置污泥的同时实现能源再生利用.本研究实地调查和监测广州越堡水泥有限公司污泥干化生产线的干化尾气成分,解析污泥干化过程产生恶臭及挥发性有机物的特征和主要来源,为污泥的有效处理处置提供科学的参考依据.结果表明,干化尾气中带有大量的恶臭物质及挥发性有机物.恶臭物质以二氧化硫等含硫物质为主,挥发性有机物以苯系物为主.污泥的性质以及热介质(窑尾气)的成分对恶臭物质及挥发性有机物的产生有影响.经过干化,污泥中的总有机物显著减少.蛋白质、挥发性脂肪酸、多糖等有机物含量也明显降低.干化尾气中的挥发性有机物来自于污泥中的有机物;二氧化硫、二硫化碳等含硫物质一部分源自污泥中的含硫物质,一部分来自于用于干化污泥的窑尾气.     

复合式生物除臭反应器处理城市污水处理厂恶臭气体

采用复合式生物除臭反应器处理北京某城市污水处理厂污泥浓缩池和脱水间散发的恶臭气体,研究了反应器对恶臭气体的净化效果和微生物悬浮生长区与附着生长区内的生物特性及对恶臭污染物的去除能力。该污水处理厂的恶臭气体中主要发臭物质为硫化氢和氨,除臭反应器的运行结果表明,在设备稳定运行期间,进气中硫化氢和氨的浓度分别为0.21～22.61 mg/m³和0.1～0.5 mg/m³,而出气中硫化氢浓度在0～0.06 mg/m³,氨浓度为0～0.02 mg/m³。对反应器内部测试表明,微生物悬浮生长区和附着生长区对硫化氢和氨都有一定的去除,但去除机理不同。硫化氢主要被附着生长区的嗜酸性硫细菌生物氧化,少量硫化氢在悬浮区溶于水被中性硫细菌氧化;氨主要在悬浮区靠生物硝化作用去除,少部分氨在附着区被去除,且多因化学中和作用转移到填料所含的水中。     

上海市某生活垃圾中转站污染特征

通过对上海市某生活垃圾中转压缩站产生的污水以及恶臭气体进行为期1年的监测和分析,研究了其污染产生的状况和变化规律。结果表明:中转站产生的垃圾压滤污水呈弱酸性,pH变化范围为5.2～6.5,污水中主要污染物SS、BOD5、CODCr、氨氮和总磷的浓度范围分别为2.00～218.21 g/L、5.50～35.20 g/L、12.06～70.60 g/L、141～909.5mg/L和31～204 mg/L,中转站压滤污水中污染物浓度大体呈现夏秋季节高而冬春季节低的特征。中转站内气体污染物中H2S、NH3气体浓度范围分别为0.005～0.20 mg/m3和0.59～2.205 mg/m3。挥发性有机物VOCs中1,2-二氯乙烷、苯、甲苯、乙酸乙酯、间二甲苯等污染物在10-1～103μg/m3之间变化。中转站污染指标和环境因素的相关分析及PCA结果表明,温度与压滤污水主要水质指标和臭气浓度气体指标存在着相关性,而H2S、NH3气体污染物与水质相关性较小。     

Performance of two biofilters with neutral and low pH treating off-gases

Two different functional biofilters were carried out and compared for the treatment of off-gas containing multicomponent odors and volatile organic compounds (VOCs) in this study. The effects of pH values and the empty bed retention time (EBRT) on the performance of the bioreactors were studied; and the characteristics of microbial populations in the two biofilters were also determined. The experimental results indicated that the removal effciencies of hydrophilic compounds such as butyric acid and ammonia ...     

细菌与真菌复合作用处理臭味气体的试验研究

针对臭味气体中发臭物质的特性, 开发了一种新型的复合式生物除臭反应器.该生物反应器由2个生物反应区构成, 并分别接种不同的微生物,细菌和真菌.利用该复合式生物反应器对臭味气体的处理进行了连续运行的试验研究.试验废气中主要污染物乙酸、氨、苯乙烯、硫化氢、乙硫醇、乙硫醚的去除率分别达到97.1%, 96.7%, 96.6%, 92.1%, 78%和83%.研究结果表明, 反应器中的细菌与真菌微生物具有协同作用, 因此该生物反应器能够有效地去除废气中亲水性和疏水性污染物质.并且,不同性质的发臭物质在2个反应区内的去除效果是不相同的.     

Release of volatile organic compounds during bio-drying of municipal solid waste

Three treatments were tested to investigate the release concentrations of volatile organic compounds (VOCs) during the bio-drying of municipal solid waste (MSW) by the aerobic and combined hydrolytic-aerobic processes. Results showed that VOCs were largely released in the first 4 days of bio-drying and the dominant components were: dimethyl disulfide, dimethyl sulfide, benzene, 2-butanone, limonene and methylene chloride. Thus, the combined hydrolytic-aerobic process was suggested for MSW bio-drying due to fewer aeration quantities in this phase when compared with the aerobic process, and the treatment strategies should base on the key properties of these prominent components. Malodorous sulfur compounds and terpenes were mainly released in the early phase of bio-drying, whereas, two peaks of release concentrations appeared for aromatics and ketones during bio-drying. Notably, for the combined hydrolytic-aerobic processes there were also high concentrations of released aromatics in the shift from hydrolytic to aerobic stages. High concentrations of released chlorinateds were observed in the later phase. For the VOCs produced during MSW bio-drying, i.e., malodorous sulfur compounds, terpenes and chlorinateds, their release concentrations were mainly determined by production rates; for the VOCs presented initially in MSW, such as aromatics, their transfer and transport in MSW mainly determined the release concentrations.     

两段生物滤池处理城市污水厂恶臭气体中试研究

采用两段式生物滤池工艺处理山东某城市污水处理厂格栅间和污泥浓缩池散发的恶臭气体,研究了反应器的运行效果、污染物去除特性和微生物特性。该污水处理厂格栅间和污泥浓缩池逸散气体的主要成分为硫化氢、氨以及由甲硫醇、二甲胺、甲醇、丙酮、乙酸、丁酸和苯乙烯等物质组成的挥发性有机化合物。应用两段式生物滤池能够有效地去除这些污染物质,...     

The ability of conditioned Microplitis croceipes (Hymenoptera: Braconidae) to distinguish between odors of aflatoxigenic and non-aflatoxigenic fungal strains

Summary. The parasitic wasp Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) learns to associate odors with food resources and subsequently exhibits a characteristic food-seeking behavior when encountering the learned odor. Wasps so conditioned, learned and subsequently demonstrated an ability to distinguish among aflatoxigenic and non-aflatoxigenic Aspergillus flavus and A. parasiticus strains. The effects of fungal species, strain, age (5, 10-12, 20, and 30 d) and growth media (potato dextrose agar, peanut agar and corn agar) on the learning and recognition responses of the conditioned wasps were examined. The level of differentiation between fungal strains by conditioned wasps was lowest when working with 5-d-old fungal cultures but increased with age and generally peaked with 20-d-old fungi. Wasps responded generally stronger to the fungal strain conditioned to independent of growth media. This ability of parasitic wasps to learn and distinguish fungal odors can open new avenues in insect learning.     

Performance of two biofilters with neutral and low pH treating o -gases

Two different functional biofilters were carried out and compared for the treatment of off-gas containing multicomponent odors and volatile organic compounds (VOCs) in this study. The effects of pH values and the empty bed retention time (EBRT) on the performance of the bioreactors were studied; and the characteristics of microbial populations in the two biofilters were also determined. The experimental results indicated that the removal effciencies of hydrophilic compounds such as butyric acid and ammonia ...     

脉冲放电等离子体治理炼油厂恶臭气体研究

应用脉冲放电等离子体技术,在线板式反应器内对炼油厂恶臭气体中代表性污染物———硫化氢、乙硫醇的去除进行了试验,试验规模4～16m3·h-1 采用闸流管开关脉冲电源,其最大输出功率1kW,最大脉冲电压峰值100kV.试验考察了峰值电压、重复频率、进口浓度、处理气量、背景气体各单因素对去除率的影响.结果表明:硫化氢几乎完全去除,乙硫醇最大去除率为84%;在有正己烷背景气体存在时,乙硫醇的去除可不受低浓度背景气体影响;在高浓背景气体情况下,乙硫醇的去除率有所降低,硫化氢也有类似规律;硫化氢和乙硫醇中硫元素主要转化为二氧化硫.结合恶臭气体去除率与能量密度、进口浓度的关系,建立反应器动力学模型,获得硫化氢和乙硫醇的氧化速率常数分别为0 042和0 034L·J-1,为进一步反应器优化、放大设计及与电源匹配提供了基础数据.