亚硝酸盐型同步脱氮除硫工艺单质硫产率及特性

采用SBR同步脱氮除硫反应器,设置了化学对照组(灭菌,不添加污泥)和生物试验组(添加污泥),以期研究亚硝酸盐型同步脱氮除硫工艺中S0的产率以及特性.发现化学对照组中NO2--N和S2--S的去除率最高可分别达到25.07％和62.26％,其主要产物为NH4+-N和S2SO32--S,并无S0生成.而在生物试验组中,NO...     

生物填料塔同步脱氮除硫的研究

本试验针对含硫化物和硝酸盐氮的人工模拟废水,以硫化物为电子供体、硝酸盐为电子受体,采用厌氧生物填料塔进行同步脱氮除硫的实验研究,探讨了该生物填料塔的启动性能及塔内生物膜菌群的生长特性。结果表明:当S/N(摩尔比)为5∶3,初始pH为8.3⁸.5,温度为28℃,进水硫化物负荷为500 g/(m3·d)时,硫和氮的去除率分别达到96.7%和87.5%;厌氧生物填料塔中的优势菌群为脱氮硫杆菌,该菌的适宜生长温度为288.5,温度为28℃,进水硫化物负荷为500 g/(m3·d)时,硫和氮的去除率分别达到96.7%和87.5%;厌氧生物填料塔中的优势菌群为脱氮硫杆菌,该菌的适宜生长温度为28³0℃,pH值范围为630℃,pH值范围为6⁷;且经驯化后该菌种对初始硫化物浓度的耐受能力提高到6257;且经驯化后该菌种对初始硫化物浓度的耐受能力提高到625¹250 g/m3。     

基质浓度冲击对同步厌氧生物脱氮除硫反应器性能的影响

采用上流式厌氧污泥床(UASB)反应器研究了基质浓度冲击对同步厌氧生物脱氮除硫反应器性能的影响.根据反应器性能对基质浓度冲击的响应特征,可将基质浓度冲击过程分为冲击期、惯性期和恢复期3个阶段.基质浓度的冲击效应与冲击强度有关.冲击强度较低(1.5倍以下的基质浓度冲击)时,反应器性能所受的影响较小;冲击强度较高(2.0倍以上的基质浓度冲击)时,反应器性能所受的影响较大,出水pH值及基质浓度显著升高.在所试验的冲击强度范围内,反应器性能受扰后均可恢复稳态,恢复时间均小于30h(7.5HRT).出水硫化物浓度对基质浓度冲击的响应较为灵敏,其受扰时的浓度值可高达10.13mg /L,为受冲击前稳定运行时的18倍,可用作反应器性能变化的指示参数.     

信号分子联合脱氮硫杆菌对同步脱氮除硫的影响

为探究信号分子联合菌对同步脱氮除硫效果的影响,发现同时投加信号分子和脱氮硫杆菌可以加快硫化物和硝酸盐氮的去除且相比单独投加时更有利于单质硫的稳定积累和氮气产量的增加,并通过FISH技术检测了反应结束后微生物总量,信号联合脱氮硫杆菌可以增加微生物总数,因此能够实现较好地脱氮除硫效果.实验从不同信号分子浓度中找出了有利于单质硫稳定积累的最佳浓度,进而在此浓度下分析了单独投加信号分子、单独投加脱氮硫杆菌,以及同时投加信号分子和脱氮硫杆菌3种情况下的脱氮除硫效果.结果表明,当硫化物浓度为200 mg·L-1时,延长反应时间至72 h后,信号分子联合脱氮硫杆菌使硫化物的去除率提高至99. 8%,硝酸盐去除率提高至96. 9%,且单质硫转化为硫酸盐的速率减慢,氮气的产量增加,反应结束后其单质硫和氮气的量分别达到59. 0 mg和80. 0 m L.当硫化物浓度为300 mg·L-1时,单独投加2. 5μmol·L-1的信号分子在72 h时其硫化物和去除率达到99. 0%,硝酸盐的去除达到93. 9%,单质硫和氮气的产量分别达到63. 1 mg和79. 5 m L.     

自养厌氧生物工艺同步脱氮除硫试验研究

在恒温水浴厌氧接触反应器中,作者接种成熟的亚硝酸盐型厌氧氨氧化菌种,投加人工配制的含硫含氮无机废水,进行自养厌氧生物工艺同步脱氮除硫的连续试验研究。分别进行了含NO_2-N和无NO_2-N废水处理的试验,试验结果表明:在NO_2-N存在的情况下,同步脱氮除硫很难实现。无NO_2-N存在的情况下,进水氨氮和硫酸根浓度分别控制在140 mg/L和480 mg/L,经过一段时间的培养驯化,发生了氨氮和硫酸根的同步去除,此时氨氮和硫酸根的平均去除率分别为20.2%和17.1%。     

响应面法优化亚硝酸型同步脱氮除硫工艺研究

采用EGSB反应器运行亚硝酸盐型同步脱氮除硫工艺.基于响应面实验设计探讨了基质浓度、水力停留时间和循环比三因素两两交互对工艺基质去除性能和单质硫产量的影响,并根据模型结果优化工艺运行条件.结果表明,基质浓度对亚硝酸盐型同步脱氮除硫工艺的基质去除性能和单质硫产量具有显著影响.高基质浓度虽有助于单质硫产生,但不利于提高基质去除率;且提高水力停留时间和循环比有助于缓解高基质浓度带来的不利影响.经过响应面模型优化,该工艺最优运行条件为:进水硫化物640.00mgS/L,水力停留时间2h和循环比30,硫化物和亚硝酸盐去除率可达(99.90%±0.03%)和100.00%,单质硫产率可达(77.75%±0.84%).     

一体式厌氧-好氧流化床反应器同步脱氮除硫实验

采用一体式厌氧-好氧流化床反应器处理含氮和含硫化物的废水,分别考察了硫氮比(硝氮和亚硝氮)、碳氮比(氨氮)等因素对同步脱氮除硫效果的影响,并对厌氧区固体产物进行了分析.实验结果表明:混养条件下获得了较好的脱氮、脱硫、去除COD的效果;s2-浓度增加对厌氧COD去除、反硝化过程无显著影响;当S2-浓度小于4.6mmol·L-1时,对厌氧氨氮去除有一定的促进作用.S/N(NO-3-N和NO-2-N)在0.2～1.7范围内.可以获得20%～75%单质硫转化率.C/NH4 4-N的降低对厌氧脱氮效果无明显影响,但可促进硫化物的去除.X射线衍射分析表明,厌氧区固体产物为单质硫.好氧进水中硫化物浓度增加对好氧区COD去除影响不明显,但S2-浓度大于15mg·L-1时会对硝化过程产生明显抑制.     

硫氮比对厌氧生物同步脱氮除硫工艺性能的影响

研究了硫氮摩尔比对厌氧生物同步脱氮除硫工艺高效性、稳定性和选择性的影响.单质硫型厌氧生物同步脱氮除硫反应(硫氮摩尔比为5:2)的硫化物和硝酸盐容积去除速率高达4.86 kg·m-3.d-1和0.99 kg·m-3.d-1工艺效能明显高于混合型和硫酸盐型(硫氮摩尔比分别为5:5和5:8).单质硫型厌氧生物同步脱氮除硫反应各项出水指标的波动相对较小,但当进水硫化物浓度超过临界值时,工效失稳,其主要原因是pH无法维持在所需范围.在所试的3种进水硫氮摩尔比下,实际反应的硫氮摩尔比有靠拢5:2的趋势.将硫氮摩尔比调控在较高水平(硫氮摩尔比为5:2),可提高同步厌氧生物同步脱氮除硫反应对单质硫和氮气的选择性.对不同硫氮比时反应物之间的电子得失情况进行了分析.     

MDAT-IAT同步脱氮除磷工艺活性污泥在不同基质中的厌氧释磷特性研究

对改进型MDATIAT(ModifiedDemandedAerationTankIntermittentAerationTank)同步脱氮除磷工艺中活性污泥在不同基质下的厌氧释磷特性进行了研究.在葡萄糖、甲酸钠、乙酸钠和丙酸钠4种单一基质中,活性污泥厌氧释磷量分别为1.58、3.55、3.04和1.86mg·L-1;释磷速率分别达到0.02、0.05、0.15和0.10mg·L-1·min-1.另外,在葡萄糖、甲酸钠、乙酸钠和丙酸钠组成的混合基质中的活性污泥厌氧释磷试验结果表明,混合基质中活性污泥释磷量和释磷速率均大于4种单一基质中的释磷量和释磷速率,分别达到8.51mg·L-1和0.31mg·L-1·min-1.     

啤酒废水同步脱氮除磷工艺启动研究

为了将短程硝化反硝化与A/O法除磷同时应用于SBR工艺处理啤酒废水,通过改变序批式反应器(SBR)工艺运行方式,使活性污泥依次经历厌氧、好氧、缺氧3个阶段,控制ρ(MLSS)=4 700 mg/L、pH=7.5～8.0、DO=0.3～0.5 mg/L(好氧阶段)。反应器内短程硝化反硝化同步除磷效果明显,氨氮去除率大于90%,亚硝酸盐积累率大于85%,磷去除率大于98%。试验结果表明短程硝化反硝化与A/O法除磷可同时应用于SBR工艺处理啤酒废水。     

Acute toxicity formation potential of benzophenone-type UV filters in chlorination disinfection process

Benzophenones （BPs） are a class of widely used UV filters, which have been frequently detected within multiple environmental matrices. Disinfection is a necessary process in water treatment processes. The transformation behaviors and toxicity changes of 14 BP-type UV filters during chlorination disinfection treatment were investigated in this study. A new index, the acute toxicity formation potential, was proposed to evaluate the toxicity changes and potential risks of BP-type UV filters during chlorination treatment. It was found that 13 of 14 BP-type UV filters exhibited toxicity decreases in the chlorination disinfection process, more or less, while one showed a toxicity increase. The toxicity changes were dependent on substitution effects, such that 2,4-di-hydroxylated or 3-hydroxylated BPs exhibited significant toxicity decreases after chlorination treatment due to the ready cleavage of the aromatic ring. Importantly, the acute toxicity changes could be duplicated in an ambient water matrix.     

不同pH值下对发光菌的毒性及QSAR研究

测定了11种苯酚类化合物在不同pH下对发光菌的急性毒性(15minEC50。)。应用两种理化参数logP和pKa对毒性数据进行了定量构效关系(QSARs)研究,并在此基础上初步探讨了苯酚类化合物的毒性机制。结果表明,苯酚类化合物对发光菌的毒性随pH的升高而减小,这与不同pH下苯酚类化合物的电离程度有关。相同pH下,苯酚类化合物的毒性随取代基团的种类、个数及取代位置而不同。苯酚类化合物属于极性麻醉(麻醉Ⅱ型)化合物,毒性可用logP和pKa来联合描述。     

GeoChip-based analysis of the microbial community functional structures in simultaneous desulfurization and denitrification process

The elemental sulfur （S^0） recover）, was evaluated in the presence of hi,ate in two development models of simultaneous desulfurization and denitrification （SDD） process. At the loading rates of 0.9 kg S/（m^3.day） for sulfide and 0.4 kg N/（m^3.day） for nitrate, SO conversion rate was 91.1% in denitrifying sulfide removal （DSR） model which was higher than in integrated simultaneous desulfurization and denitrification （ISDD） model （25.6%）. A comprehensive analysis of functional diversity, structure and metabolic potential of microbial communities was examined in two models by using functional gene array （GeoChip 2.0）. GeoChip data indicated that diversity indices, community structure, and abundance of functional genes were distinct between two models. Diversity indices （Simpson＇s diversity index （1/D） and Shannon-Weaver index （H′）） of all detected genes showed that with elevated infiuent loading rate, the functional diversity decreased in ISDD model but increased in DSR model. In contrast to ISDD model, the overall abundance of dsr genes was lower in DSR model, while some functional genes targeting from nitrate-reducing sulfide-oxidizingbacteria {NR-SOB）, such as Thiobacillus denitrficans, Sulfurimonas denitrificans, and Paracoccus pantotrophus were more abundant in DSR model which were highly associated with the change of SO conversion rate obtained in two models. The results obtained in this study provide additional insights into the microbial metabolic mechanisms involved in ISDD and DSR models, which in turn will improve the overall performance of SDD process.     

Experimental study on the simultaneous desulfurization and denitrification by duct injection

The highly active absorbent with oxidization based on fly ash, lime and additive was prepared.Experiments of simultaneous desulfurization and denitrification were carried out using fixture bed and duct injection.The influencial factors for the absorptive capacity of the absorbent were studied. The absorptive capacities of 120.7 mg for SO2 and 43.7 mg for NOx were achieved at a Ca/(S N) molar ratio 1.2, respectively, corresponding removal efficiencies of 87% and 76%, while spent absorbent appeared in the form of dry powder. The optimal temperature and humidity of flue gas treated with this process were shown to be approximately 50℃, and 5% respectively. The mechanism of removal for SO2 and NOx was investigated. In comparison with traditional dry FGD,this process appears to have lower cost, less complicated configuration and simpler disposal of used absorbent. The valuable references can be provided for industrial application by this process. The foreground of application will be vast in China and in the world.     

废水同步脱硫脱氮关键工艺参数及微生物群落结构的研究

大量未经处理的含硫化物和硝酸盐废水的排放将带来严重的环境问题.根据以废治废原则,使用厌氧滴滤塔反应器构建的同步脱硫耦联反硝化脱氮反应(SDD)能很好的去除废水中S~(2-)和NO-x-N.其中以聚氨酯泡沫为填料的厌氧滴滤塔反应器中生物活性最强,脱氮脱硫效果最好.体系中功能菌优先将S~(2-)氧化成S0,待S~(2-)去除完全后,再进一步将S0氧化成SO_4~(2-).同时,SDD反应降解NO_3~--N的速率快于NO_2~--N.进水S/N摩尔比越大,产物中SO_4~(2-)相对含量越低.结合实际工程考虑,应控制进水S/N摩尔比在5/3~5/2之间,S~(2-)浓度控制在538 mg·L-1以下.微生物群落结构分析结果表明,Thiobacillus属在4组反应器上占绝对优势,其相对丰度均高于40%.其次相对丰度较高的Rhodanobacter、Arenimonas和Truepera属与厌氧反硝化作用密切相关.对4组反应器中微生物进行Alpha-多样性分析结果表明取得较好脱硫耦联反硝化效果的体系中物种多样性指数也较高.     

明亮发光杆菌毒性试验在生活饮用水水质监测中的应用

5．12四川汶川地震发生以后,为保障救灾部队及灾区群众的饮水安全,成都军区环境监测中心站对成都军区联勤部设在北川的供水站进行了水质监测,采用明亮发光杆菌毒性试验测定饮用水的急性综合毒性。结果表明,该供水站出水对生物体的急性综合毒性为低毒。测定结果与pH、氰化物、挥发酚、六价铬、砷、汞、硝酸盐氮等理化指标的监测结果有可比性,建议将两类监测方法结合使用。     

重金属Zn、Pb和Cd对可口革囊星虫的急性毒性作用

研究了必需元素Zn及非必需元素Pb、Cd对可口革囊星虫(Phascolosoma esculenda)的急性毒性作用,得到Zn2 的48 h LC50和96 h LC50分别为61.09、10.91 mg/L;pb2 的48 h LC50和96 h LC50分别为29.44、10.59 mg/L;Cd2 的48 h LC50和96hLC50分别为10.69、4.46mg/L.估算得到Zn、Pb和Cd对可口革囊星虫的安全浓度分别为0.55、0.53和0.22mg/L.     

用QSAR模型预测苯酚类化合物对发光菌的联合毒性

测定了苯酚与11种取代苯酚对发光菌的单一毒性和毒性单位比为1:4,1:1,4:1二元混合物的联合毒性.采用相加指数法对联合毒性进行了评价,结果表明,苯酚和取代苯酚的二元混合物对发光菌的联合作用以相加作用为主.在此基础上,根据12种苯酚类化合物的单一毒性建立了QSAR方程: -lgEC₅₀=6.158-0.279pKa,对混合物中取代苯酚的毒性进行了预测,预测值与实测值吻合较好.     

Experimental study on simultaneous desulfurization and denitrification based on highly active absorbent

Simultaneous removal of SO2 and NO from flue gas by the highly active absorbent prepared from fly ash, lime and a few oxidizing manganese compound additive was studied using a flue gas circulating fluidized bed （CFB） under different experimental conditions. The effects influencing the removal effiencies were discussed. The optimal flue gas temperature, flue gas humidity, gas velocity of CFB and Ca/（S＋N） molar ratio with this process were approximately 110℃, 6%, 1.8 m/s and 1.05, respectively. Removal efficiencies of 92.3% for SO2 and 60.88% for NO were obtained under the optimal experimental conditions. While the spent absorbent appeared in the form of dry powder, the mechanism of removal for SO2 and NO based on the highly active absorbent was investigated by a scanning electron microscope （SEM）, a X-ray energy spectrometer and the chemical analysis methods. The valuable references can be provided for industrial application by the process. The foreground of application will be vast in China and in the world.     

Nitrogen removal and simultaneous nitrification and denitrification in a fluidized bed step-feed process

For urban wastewater treatment, we conducted a novel four-stage step-feed wastewater treatment system combined with a fluidized bed laboratory experiment to investigate chemical oxygen demand (COD), NH₄⁺-N, and total nitrogen (TN) removal performance. The removal rates of COD, NH₄⁺-N and TN were 88.2%, 95.7%, and 86.4% with effluent concentrations of COD, NH₄⁺-N and TN less than 50, 8, and 10 mg/L, respectively. Biomass and bacterial activities were also measured, with results showing more nitrobacteria in the activated sludge than in the biofilm; however, bacterial activity of the biofilm biomass and the activated sludge were similar. Nitrogen concentrations during the process were also detected, with simultaneous nitrification and denitrification found to be obvious.