厌氧流化床反应器处理含硫废水毒性的实验

采用多孔聚合物载体固定化微生物在厌氧流化床（AFB）反应器中处理含硫废水,研究反应器抗硫化物（S^2－）毒性抑制和抗硫酸盐毒性抑制的能力;探索解除 S^2－毒性的方法．研究表明,当进料基质 COD浓度为 5000mg/L,HRT为5.2－5.4h,S^2－＜200mg/L时,反应器去除 COD效果不受影响,S^2－350mg/L时,厌氧消化受到明显抑制,反应器可容忍530mg/L S^2－浓度而未造成消化系统的破坏;SO₄^2－浓度高达3521mg/L,COD去除率仍可达77％－80％,但SO₄^2－去除率明显下降;当COD/SO₄^2－的比值大于1.45时,硫酸盐还原菌和产甲烷菌的生长未受到明显抑制,此时容积负荷为22－24kgCOD/（m³>·d）,COD去除率为80％,SO₄^2－去除率为58.8％;向反应器投加适量FeCl₂可很好地解除S^2－的抑制．     

In situ sequential treatment of a mixed contaminant plume

Groundwater plumes often contain a mixture of contaminants that cannot easily be remediated in situ using a single technology. The purpose of this research was to evaluate an in situ treatment sequence for the control of a mixed organic plume (chlorinated ethenes and petroleum hydrocarbons) within a Funnel-and-Gate. A shallow plume located in the unconfined aquifer at Alameda Point, CA, was found to contain up to 218,000 μg/l of cis-1,2 dichloroethene (cDCE), 16,000 μg/l of vinyl chloride (VC) and <1000 μg/l of 1,1 dichloroethene (1,1 DCE), trans-1,2 dichloroethene (trans-1,2 DCE) and trichloroethene (TCE). Total benzene, toluene, ethylbenzene and xylenes (BTEX) concentrations were <10,000 μg/l. Contaminated groundwater was funneled into a gate, 3.0 m wide, 4.5 m long and 6.0 m deep (keyed into the underlying aquitard) where treatment occurred. The initial gate segment consisted of granular iron, for the reductive dechlorination of the higher chlorinated ethenes. The second segment, the biosparge zone, promoted aerobic biodegradation of petroleum hydrocarbons and any remaining lesser-chlorinated compounds, stimulated by dissolved oxygen (DO) and carbon dioxide (CO₂) additions via an in situ sparge system (CO₂ was used to neutralize the high pH produced from reactions in the iron wall). Groundwater was drawn through the gate by pumping two wells located at the sealed, downgradient, end. Over a 4-month period an estimated 1350 g of cDCE flowed into the treatment gate and the iron wall removed 1230 g, or 91% of the mass. The influent mass of VC was 572 g and the iron wall removed 535 g, corresponding to 94% mass removal. The other chlorinated ethenes had significantly lower influent masses (3 to 108 g) and the iron wall removed the majority of the mass resulting in >96% mass removal for any of the compounds. In spite of these high removal percentages, laboratory column tests indicated that at these levels of chlorinated contaminants, surface saturation of the iron grains likely contributed to lower than expected reaction rates. In the biosparge zone, mass removal of cDCE appeared to occur predominantly by biodegradation (65%) with volatilization (35%) being an important secondary process. The dominant removal process for VC was volatilization (70%) although significant biodegradation was also indicated (30%). Laboratory microcosm results confirmed the potential for aerobic biodegradation of cDCE and VC. When average influent field concentrations for cDCE and VC were 220,000 and 46,000 μg/l, respectively, the sequential treatment unit removed 99.6% of the total mass and when the influent concentrations decreased to 26,000 and 19,000 μg/l for cDCE and VC, respectively, >99.9% removal within the treatment gate was attained. BTEX compounds were found to be significantly retarded in the iron treatment zone. Although they did eventually break through the granular iron, and into the gravel transition zone, none of these compounds was detected in the biosparge zone. No noticeable interferences between the anaerobic (reductive) and aerobic parts of the system occurred during testing. The results of this experiment show that in situ treatment sequences are viable, although further work is needed to optimize performance.     

铁促电解法处理垃圾渗滤液中有机污染物

采用铁促电解法处理垃圾填埋场渗滤液;考察了FeSO₄浓度、初始pH值、电流(电压)对污染物去除的影响.结果表明,与传统电解氧化降解有机物相比,铁促电解显著提高了有机污染物的去除效率;FeSO₄浓度越大,有机物去除效果越高;电解介质合理的初始pH值为3.0～4.0;铁促电解对渗滤液COD_Cr与NH₃^-N的去除率分别为68.37%,89.07%,色度和浊度的去除率大于98%.     

喷消石灰脱除垃圾焚烧炉尾气中HCl和SO2的试验研究

在日处理200t进口流化床垃圾焚烧炉上,进行烟气喷水降温加上喷消石灰粉末脱除尾气中的酸性气体HCl和SO2的试验研究,HCl和SO2浓度由布袋除尘器出口的在线气体分析仪测得,结果表明HCl和SO2的去除率在Ca/Cl摩尔比等于9时分别为80%和20%,说明该法消石灰利用率较低,宜改为半干法脱除HCl和SO2酸性气体,以便降低吸收剂用量,提高运行的经济性.     

气-固流化床光催化氧化甲苯的研究

在自制的流化床光催化反应装置中研究了中低浓度(28~140mg/m3)甲苯的气相光催化降解过程,考察了光照时间、初始浓度、表观气速和催化剂负载量等因素对甲苯光催化降解率的影响规律。结果表明,紫外灯照射约1·5h,甲苯的转化率达最大值,甲苯初始浓度越低,维持此最大值的时间越久;在一定低浓度范围内(28~55mg/m3),甲苯的转化率不随浓度变化,符合一级反应动力学,浓度进一步增加,则甲苯的转化率下降;表观气速和催化剂负载量的最佳值分别为3·3Umf和0·19gTiO2/gSiO2。     

氮磷在阶式水生植物床中的去除效果及组成变化

利用串联运行的阶式水生植物床净化富营养化河水。考察了不同形态的氮磷在处理前后的浓度变化,在此基础上阐述水生植物床去除富营养化水体中氮磷的过程与机理。在水力负荷为74cm/d的条件下,总磷和总氮的去除率分别达73.1%和64.5%。植物根系对悬浮物的截留对去除河水中的氮磷起关键作用。采用多级串联的运行方式能有效克服一般湿地运行一段时间后因沉积物释放作用而引起处理水溶解性营养盐浓度上升的难题。     

HCl emission characteristics and BP neural networks prediction in MSW/coal co-fired fluidized beds

IntroductionWiththedepletionofspaceforlandfillingofmunicipalsolidwasteandtherisingpricesforrawmaterials ,moreandmorefluidizedbedincineratorshavebeenusedtotreatMSWduetotheprimaryadvantagesofhygieniccontrol,volumereductionandenergyrecovery .BecausetheMSWhas…     

散射光下铁(Ⅲ)-丙酮酸盐配合物还原铬(Ⅵ)的研究

研究了在散射光下铁（Ⅲ）-丙酮酸盐配合物对铬（Ⅵ）的光还原反应;考察了溶液pH、铁（Ⅲ）、丙酮酸钠、铬（Ⅵ）浓度对反应的影响;分析了铬（Ⅵ）光还原反应的动力学。实验结果表明：铁（Ⅲ）-丙酮酸盐配合物体系能在较弱的散射光下还原铬（Ⅵ）。在铬（Ⅵ）浓度为19．2μmol／L、铁（Ⅲ）浓度为10．0μmol／L、丙酮酸钠浓度为240μmol／L、pH为3．0、光照240min的条件下,铬（Ⅵ）的还原率达到99．7％。从表观动力学方程的反应级数看,铁（Ⅲ）的级数（0．83）最高,铁（Ⅲ）浓度是影响铬（Ⅵ）光还原反廊速率的主要因素．铁（Ⅱ）是铬（Ⅵ）光还原的主要还原剂。     

载体好氧预挂膜处理对厌氧生物颗粒性能的影响

研究了生物膜载体经好氧预挂膜处理对厌氧附着膜膨胀床(AAFEB)反应器中生物颗粒性能的影响.载体经10 d好氧预挂膜处理后,形成了7～8 μm厚的生物膜,在起动运行过程中,处理反应器中载体的挂膜进程比对照要快.在整个运试期间,处理反应器中的生物膜厚度和污泥浓度值均高于对照.前者厌氧生物颗粒致密、结实,生物膜结构良好,滞留于反应器中的性能较佳,比后者较不宜随水流失.处理反应器厌氧生物颗粒的一些性能指标值,如最大比产酸活性、最大比产甲烷活性、脱氢酶活性、辅酶F₄₂₀含量等均高于对照.另外,厌氧生物颗粒内微生物相也有明显的差异.      

铁硫化物对高砷地下水中As(Ⅲ)的去除效果研究

高砷地下水具有极高的毒性,人类长期饮用高砷地下水可造成砷中毒.在查明山阴地区高砷地下水污染特征的基础上,将室内批试验与PHREEQC软件数值模拟相结合,考察了投料比、pH值对铁硫化物除砷效果的影响,为原位修复高砷地下水工艺确定了最佳条件.结果表明:山阴地区砷超标地下水样的pH值为7.6?8.5,总砷浓度为17～242 ...