Sulfate reducing bacterial community and in situ activity in mature fine tailings analyzed by real time qPCR and microsensor

Sulfate reducing bacteria(SRB) play significant roles in anaerobic environments in oil sands mature fine tailings(MFTs). Hydrogen sulfide(H2S) is produced during the biological sulfate reduction process. The production of toxic H_2S is one of the concerns because it may hinder the landscape remediation efficiency of oil sands tailing ponds. In present study, the in situ activity and the community structure of SRB in MFT and gypsum amended MFT in two settling columns were investigated. Combined techniques of H_2S microsensor and dissimilatory sulfite reductase β-subunit(dsrB) genes-based real time quantitative polymerase chain reaction(qPCR) were applied to detect the in situ H_2S and the abundance of SRB. A higher diversity of SRB and more H_2S were observed in gypsum amended MFT than that in MFT, indicating a higher sulfate reduction activity in gypsum amended MFT; in addition, the activity of SRB varied as depth in both MFT and gypsum amended MFT: the deeper the more H_2S produced. Long-term plans for tailings management can be assessed more wisely with the information provided in this study.     

翻堆频率对厨余垃圾堆肥过程中H_2S和NH_3排放的影响

为研究厨余垃圾堆肥过程中翻堆频率对H2S和NH3排放的影响,以大类粗分后的厨余垃圾为研究对象,玉米秸秆为调理剂,设置4组翻堆频率不同的处理(每周2次,2周1次,2周1次和不翻堆)进行对比研究。结果表明:翻堆频率的变化对H2S的排放影响不大,对NH3的排放有显著的影响,翻堆频率过高会增加NH3的累积排放量,翻堆频率过低虽然能降低NH3的累积排放量,但会影响到堆肥产物的腐熟。综合厨余垃圾堆肥的无害化指标、H2S和NH3的排放以及最终堆肥产品的毒性检验,在实验条件下,翻堆频率设为每周1次在堆料腐熟的基础上对H2S和NH3减排效果最好。     

板式生物滴滤塔高效净化硫化氢废气的研究

采用营养液分层喷淋、pH分别在线控制(pH 2.5、 4.5、 6.5)的板式生物滴滤塔(plate type-biotrickling filter, PTBTF)净化H₂S废气,考察PTBTF于挂膜启动及稳定运行阶段对H₂S的降解性能.结果表明,PTBTF系统在14 d内即完成挂膜,对浓度为188.6mg·m^-3的H₂S去除率达到100%;在进口浓度100～1000mg·m^-3、空床停留时间(EBRT)28～4 s的条件下,H₂S的去除率可达到99%以上;当H₂S去除率≥90%时, PTBTF系统的最大去除负荷随EBRT(3.3～6 s)的增加而增大,EBRT 6 s的最大去除负荷达到1019.0g·(m³·h)^-1;上、中、下3层填料对H₂S的去除负荷随进口H₂S负荷的波动呈显著变化;通过荧光染色观察填料上的细胞数,发现在挂膜阶段微生物数量增长明显,第125 d上层、中层和下层填料上的菌落数(以干填料计)分别达到了1.29×10⁷、 5.47×10⁸和1.07×10⁹个·g^-1;采用扫描电镜观察填料表面的生物膜,可见上填料层和下填料层的优势菌分别为杆菌和丝状菌;利用变性梯度凝胶电泳初步揭示了系统运行过程中生物群落的演替规律;通过对产物的分析,确定该PTBTF系统降解H₂S后主要产生SO^2-₄和单质硫.     

串联组合离子选择电极的研究——利用Ag2S电极测定废水中S2-离子含量

本文依据电池串联原理将多组电极串联组合,减少了因电动势测量误差而造成的测定浓度的相对误差,明显地提高了测定的精密度和准确度.对工业废水中S~(2-)离子含量的测定结果令人满意.其相对偏差低于2.5％,方法回收率为97.5—101.7％,明显优于现有离子选择电极测定方法.与比色法进行比较,测得结果基本一致.     

硫化钠处理含汞废水

为了消除汞污染,采用硫化钠沉淀含汞废水。研究结果表明,出水中汞的含量小于国家规定的排放标准（0.05mg/L）,沉渣体积小,且化学稳定性很好,易处置。此法具有工艺简单,操作方便,反应速度快,沉淀效率高,随废水中含汞浓度的高低投加不同量的硫化钠,根据废水量的大小,可连续处理和间歇处理,处理费用低等优点。该法可在中小型化工行业中推广应用。     

二甲基硫醚光解及二甲基二硫醚生成速率研究

用低压汞灯照射二甲基硫醚（ＤＭＳ）,在２０ｍ的长光池中用富里叶红外光谱仪测量其光解产物,结果表明二甲基硫醚光解生成二甲基二硫醚（ＤＭＤＳ）和乙烷。测量其不同光照时间的光解产物,结果表明Ｉｎ＾ｃ０／ｃｔ在直解坐标上是一条直线,说明了二甲基二硫醚生成按生一极反应进行,其生成的速率常数为８．７０×１０＾－５ｓ＾－１用低压汞灯照射ＤＭＳ＋Ｈ２Ｏ２体系,富里叶红外光谱检测其产物,在有足够的Ｈ２Ｏ２情况下,生     

SW型脱硫剂脱硫性能的研究

以硫酸烧渣为主要原料制备ＳＷ型脱硫剂,并对其脱硫性能进行了研究,对半水煤气、葡萄酒厂污水处理产生的沼气和焦炉煤气、水煤气中的Ｈ２Ｓ进行了工业脱硫试验,经半年以上运行证明,可使其Ｈ２Ｓ含量从３０００－５０００ｍｇ／ｍ＾３降为２０ｍｇ／ｍ＾３以下（符合国家标准）,当脱硫剂工作硫容达３０％时可返回硫酸生产中,再生周期一般为３个月,其主要性能达到国内外同类产品水平。     

硫化碱脱除二氧化硫工业烟气的可行性分析

分析了国内外烟气脱硫的研究现状,论述了用硫化碱脱除二氧化硫化工业烟气在理论上和实验上的可能性。     

Biological removal of air loaded with a hydrogen sulfide and ammonia mixture

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.     

川东北三高气田钻完井风险因素分析

分析了三高（高压、高产、高含硫）气田存在的主要有害因素,以及三高气田钻完井作业过程中存在的主要危险及其发生的潜在原因,并提出了相应的控制措施。针对我国三高气田区域地质环境的特殊性,分析了我国三高气田钻完井过程中可能诱发事故的特殊因素,并对应对措施进行了探讨。