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UASCB-SMBR处理垃圾渗滤液的试验研究 总被引:1,自引:1,他引:0
研究了厌氧污泥复合床 (UASCB) 序批式膜生物反应器 (SMBR)串联工艺 ,处理垃圾渗滤液的工艺性能及影响因素 ,并与单纯的SMBR工艺进行了对比。试验结果表明 ,在进液COD浓度平均为 2 50 0mg/L ,NH+ 4-N平均浓度为 360mg/L ,厌氧反应器COD的负荷为 7~2 0kgCOD/m3·d ,SMBR负荷为 1~ 5kgCOD/m3·d,系统总水力停留时间为 1 4~ 2 8h时 ,该串联工艺COD去除率达到 92 %以上 ,NH+ 4-N的去除率在 80 %以上 相似文献
413.
固定污染源氨气的手工监测,干扰因素较多,其中采样环节尤为关键。实验通过催化氧化-化学发光法考察不同采样管线材质对氨气的吸附效果,离子色谱法考察化学吸收法采集氨气的吸收瓶类型、采样流量、吸收液种类、吸收液浓度及体积等采样条件对氨气吸收效率的影响。实验表明,316 L不锈钢与聚四氟乙烯对氨气的吸附较小,氨气的采样流量不宜超过1.0 L/min,棕色气泡式吸收瓶更适用于氨气样品的采集,磷酸溶液作吸收液对氨气的吸收效率较好,对于低浓度的氨气样品,应采用低流量长时间采集。 相似文献
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The nuisance impact of air pollutant emissions from wastewater pumping stations is a major issue of concern to China. Hydrogen sulfide and ammonia are commonly the primary odor and are important targets for removal. An alternative control technology, biofiltration, was studied. The aim of this study is to investigate the potential of unit systems packed with compost in terms of ammonia and hydrogen sulfide emissions treatment, and to establish optimal operating conditions for a full-scale conceptual design. The laboratory scale biofilter packed with compost was continuously supplied with hydrogen sulfide and ammonia gas mixtures. A volumetric load of less than 150 gH2S/(m^3.d) and 230 gNH3/(m^3.d) was applied for about fifteen weeks. Hydrogen sulfide and ammonia elimination occurred in the biofilter simultaneously. The removal efficiency, removal capacity and removal kinetics in the biofilter were studied. The hydrogen sulfide removal efficiency reached was very high above 99%, and ammonia removal efficiency was about 80%. Hydrogen sulfide was oxidized into sulphate. The ammonia oxidation products were nitrite and nitrate. Ammonia in the biofilter was mainly removed by adsorption onto the carrier material and by absorption into the water fraction of the carrier material. High percentages of hydrogen sulfide or ammonia were oxidized in the first section of the column. Through kinetics analysis, the presence of ammonia did not hinder the hydrogen sulfide removal. According to the relationship between pressure drop and gas velocity for the biofilter and Reynolds number, non-Darcy flow can be assumed to represent the flow in the medium. 相似文献
417.
Osmotic distillation (OD) was found to be a coupled process in membrane absorption (MA) for the treatment of high strength ammonia wastewater. As a result, ammonia could not be concentrated in absorption solution(AS) as expected. The inhibition of the coupled OD in MA process was investigated as well as various factors affecting the inhibition. The results indicated that the coupled OD can be effectively inhibited by heating concentrated solution and cooling dilute solution. It was also found that experimental minimum inhibition temperature difference(MITD) between concentrated and dilute solutions was different when using polyvinylidene fluoride(PVDF) and polypropylene(PP) membranes respectively, which could be ascribed to material properties, such as OD and membrane distillation (MD) coefficients of the membranes. Experimental MITDs were found to be higher than theoretical MITDs which were calculated using a simplified method. 相似文献
418.
针对高斯模型中忽略物质质量流率的变化导致模拟结果与实际存在偏差的问题,将物质质量流率根据泄漏持续时间进行离散化处理,获得不同时间段的物质泄漏量,以此对高斯烟团叠加模型进行修正,得到若干烟团不同时刻的浓度分布模型,并以液氨储罐泄漏事故为研究对象,获得较恒速泄漏条件具有明显差异的有毒云团危害区域。针对其后果偏差产生的原因——罐内初始压力Pn及储罐的充装水平α进行研究,分别比较在不同的Pn及α取值情况下泄漏后果的变化及差异。研究表明,增大Pn或减小α能够有效减小液氨泄漏的危害距离,并且会减小恒速泄漏条件分析后果的偏差,对液氨等罐区的管理提供依据。 相似文献
419.
厌氧氨氧化菌富集培养过程微生物群落结构及多样性 总被引:2,自引:0,他引:2
为深入理解厌氧氨氧化菌富集培养过程微生物群落变化特征,采用ASBR反应器进行厌氧氨氧化菌富集培养,考察了不同培养时间微生物群落组成、多样性及物种网络关系.结果表明,通过逐步提高基质浓度,实现了厌氧氨氧化菌富集,NH4+-N和NO2--N去除率分别为97.6%和95.4%,总氮去除率为84.9%.高通量测序发现,整个培养过程优势菌门(相对丰度>5%)为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、绿弯菌门(Chloroflexi)、浮霉菌门(Planctomycetes)、装甲菌门(Armatimonadetes)和放线菌门(Actinobacteria);富集培养获得的主要厌氧氨氧化菌为Candidatus Brocadia,相对丰度从1.42%增长到24.66%;培养过程,微生物群落优势菌群组成未发生变化,但相对丰度呈现显著差异(P<0.05).富集培养过程不同时间,微生物群落α多样性呈现先升高后降低的趋势,且存在显著差异(P<0.05);微生物群落β多样性在富集培养过程发生明显空间分异特征,且存在显著差异(R=0.5672,P<0.01).培养过程不同时间,物种网络密度分别为0.188、0.068、0.059、0.18和0.0735;虽然富集培养过程导致微生物间的关联作用变弱,但浮霉菌门相关类群的物种成为网络中的主要节点. 相似文献
420.
Municipal solid waste (MSW) is one of the most well-known biomass resources that can be utilized to produce renewable energy. Numerous countries are plagued by the proliferation of waste, particularly organic waste that can be utilized for energy recovery. Palestine suffers from inefficient solid waste management, and only recently have a few projects focused on bioenergy production been implemented. Throughout the years, the city of Tulkarm experiences power outages which cause a challenge to the Palestine Technical University-Kadoorie campus in Tulkarm. Thus, the possibility of energy recovery from the organic portion in Palestine Technical University-Kadoorie was evaluated. The analysis of an economic impact included discussions of a number of economic aspects, including Levelized cost of energy, internal rate of return, present worth, annual worth, and payback period. On the other hand, a carbon dioxide savings analysis and gas emission were evaluated. The outcomes of the energy optimization demonstrated that the suggested system could supply the institution with an average of roughly 7 MWh of electrical energy. According to the economic study, this project offers 0.25 million dollars in present value, 0.144 million dollars in annual value, a 13 percent internal rate of return, a payback period of 6 years, and a levelized cost of energy of 0.11 dollars for each kWh generated. Additionally, the environmental assessment revealed that this system might reduce CO2 emissions by around 8,343,778 tons. For effective waste management, energy recovery, and emission reduction, it is advised to implement anaerobic digestion technology. 相似文献