三电极系统处理含藻水

以铝、掺硼金刚石为阳极,不锈钢为阴极构建三电极系统处理含藻水,考察了电流密度、通电时间、沉降时间、初始pH、极板间距对处理效果的影响。结果表明,各因素对藻的去除率的影响顺序为:电流密度通电时间沉降时间初始pH极板间距,而且电流密度2 m A·cm~(-2),通电时间为30 min,沉降时间为15 min,pH=6,极板间距取1.0 cm为实验的最优工况点。     

钯修饰碳纳米管电极电催化氧化三氯生

采用钯修饰多壁碳纳米管(MWCNTs)电极电催化氧化降解三氯生,考察了极板间距、电流密度、离子强度、pH、初始浓度和电解时间对三氯生去除效率的影响,并探讨了其反应动力学。结果表明:钯修饰多壁碳纳米管(MWCNTs)电极电催化氧化降解三氯生的最佳条件为:三氯生初始浓度为50 mg/L,电流密度约为10 mA/cm2,极板间距为1 cm,pH为11,电解质Na2SO4浓度为1 000 mg/L。此条件下,反应时间为3 h时三氯生的去除率可达到99%以上,三氯生的降解为零级反应。     

电芬顿法去除兰炭废水COD

为处理高浓度生物难降解兰炭废水,考查了利用不锈钢作阳极和石墨气体扩散电极作阴极构成的电芬顿体系对兰炭废水COD的去除效果。系统地考察了空气流速、电流密度、溶液pH值及极板间距等因素对废水COD去除率的影响。电解过程的较佳条件:空气流速为2.5 L/min;电流密度为5.2 mA/cm2;溶液pH值为3;极板间距为2 cm。电芬顿法处理兰炭废水240 min之后,COD最高去除率可达78.62%,实现了对兰炭废水的预处理,为兰炭废水的处理提供了新的途径。     

RuO2-IrO2-SnO2/Ti阳极电催化氧化苯酚的研究

以RuO2-IrO2-SnO2/Ti钛网电极为阳极,RuO2-IrO2/Ti钛网电极为阴极,构建了电催化氧化体系,同时以苯酚为底物、硫酸钠为电解质,考察了不同pH、极板间距、电流密度和苯酚初始浓度对苯酚去除率的影响。结果表明,在pH为6.5、极板间距为1.0cm、电流密度为50mA/cm2、苯酚初始质量浓度为1 000mg/L的最佳实验条件下,取硫酸钠质量浓度为20g/L的苯酚模拟废水250mL,120min时苯酚去除率可以达到98.4%。     

电化学氧化法去除微污染水中的氨氮

以低氯离子浓度下微污染水中的氨氮(NH4+-N)为研究对象,采用电化学氧化法对污染水中的氨氮进行去除。通过静态和正交实验得到了极板的最佳运行参数。实验结果表明:Cl-浓度在各影响因素中对NH4+-N去除影响最大,且在其他影响因素不变的条件下,通过改变电解电流是解决动态运行时NH4+-N去除率下降较经济有效的方法。最佳运行工艺条件为:电流密度10 mA/cm2,电解时间10 min,极板间距1 cm,溶液初始pH为7,Cl-浓度100 mg/L,面体比102 m2/m3,氨氮的平均去除率在80%以上。     

掺硼金刚石三电极系统处理垃圾渗滤液实验研究

实验以掺硼金刚石电极为阳极构建三电极系统处理稳定的垃圾渗滤液。考察了稀释比、初始pH值、电流密度和极板间距4个因素对垃圾渗滤液污染物去除率的影响。实验结果表明,电流密度、稀释比是影响电化学氧化垃圾渗滤液的主要因素,极板间距、初始pH值对电化学氧化垃圾渗滤液的影响较小。在稀释比为1∶2、电流密度为75 mA/cm2、pH值未调节、极板间距为10 mm最优工况时,经过5 h电化学氧化后NH+4-N、COD均能完全去除;NH+4-N、COD去除率分别满足线性方程y=21.759t、y=20.717t,对应的线性相关系数为0.9923和0.9925。最优工况条件下,BDD电极电化学氧化垃圾渗滤液的能耗为260 kWh/m3。     

三维电催化氧化技术处理草铵膦农药废水

选用石墨板作为三维电催化装置的阳极、不锈钢板作为阴极,以活性炭颗粒作为粒子电极进行反应,研究了三维电催化氧化技术处理草铵膦农药废水的效果;并考察了电流密度、极板间距、电解时间、初始浓度、pH值和粒子电极用量等因素对其处理效果的影响。实验结果表明,在废水初始浓度为300 mg·L~(-1),反应时间为90 min,极板间距为4 cm,pH值为5,电流密度为31.5 m A·cm-2,粒子电极的用量为3.08 g·L~(-1)的条件下,废水的COD去除率为83.48%。三维电催化氧化技术通过减小粒子间距改善电荷传质效果;电流效率的提高也促使废水的处理效果显著提升。     

三维电极法深度处理维生素生产废水

采用三维电极法对维生素废水进行深度处理,分别以钛涂钌铱板、铁板和不锈钢板作为电极阳极,石墨板作为电极阴极,柱状活性炭作为粒子电极,结果表明,当以钛涂钌铱板作为阳极,以粒径为1 mm的柱状活性炭作为粒子电极时电解效果最好,COD和色度去除率最高。实验选择电解电压、电极板间距、电解时间和初始pH值作为主要影响因素进行正交实验,实验研究证明,各因素的影响大小为电解电压>电极板间距>电解时间>初始pH值,得到的最佳参数组合分别为:电解电压为10 V,电极板间距为8 cm,电解时间为20 min,初始pH值为4,得到COD和色度最大去除率分别为59.5%和93.57%。     

电解絮凝法处理老龄垃圾渗滤液的实验研究

为考察简便低耗的电解材料处理效果,采用铸铁阳极电解絮凝法对老龄垃圾渗滤液进行了处理,通过正交实验和单因素实验考察了电解液浓度、电流密度、pH、极板间距对处理效果的影响.结果表明,电解絮凝法对该老龄垃圾渗滤液有较好的处理效果,当电流密度为50 mA/cm2、pH值为9、极板间距为2 cm、电解75 min后,COD和NH...     

Ce-PbO_2/C电极的制备及其去除水中酸性红B

采用电沉积法制备铈修饰的PbO2/C电极,通过SEM、XRD、XPS及循环伏安对PbO2/C、Ce-PbO2/C电极进行表征,结果表明,Ce-PbO2/C电极比PbO2/C颗粒细小,表面均匀致密,电化学氧化能力较强,修饰电极中Ce以CeO2的形态存在。以Ce-PbO2/C为工作电极,电解浓度为1 000 mg/L的高盐酸性红B模拟活性染料废水,考察了电压、pH、电解质浓度、极间距对脱色率、氨氮去除率及COD去除率的影响。确定适宜工艺条件为：初始酸性红B溶液浓度为1 000 mg/L,pH值为6,电压10 V,电解时间1 h,电极间距1.5 cm,该条件下脱色率、氨氮去除率和COD去除率分别为99.98%、97.23%和90.17%。通过UV-Vis及GC-MS初步分析了降解过程可能存在的中间产物及降解途径。     

氯离子对氨氮电化学氧化的影响

以自制的二氧化铅粉末多孔电极为阳极,不锈钢为阴极,探讨了投加Cl-对氨氮电化学氧化反应速率、途径及产物等的影响。结果表明,投加Cl-能显著提高氨氮的电化学氧化速率;有氯离子存在的条件下,氨氮的去除主要靠电催化过程中产生的强氧化性物质.OH,HClO的作用,其去除率随着电流密度的增大呈增高的趋势,随初始pH的增大而增大;投加氯离子后,NO3--N的生成量增加,但氧化产物主要是以N2为主的含氮气体。     

组合阳极联合气体扩散阴极电催化降解苯胺

采用气体扩散电极为阴极,钛基氧化物（Ti／SnO2-Sb2O5-IrO2）和金属铁构成组合阳极,构建了新型电化学氧化体系用于降解有机污染物。利用该氧化体系,在不同实验条件下考察了苯胺降解的效果与降解过程的相关规律。结果表明,阴极电位、铁阳极通电时间以及苯胺初始浓度均显著影响苯胺的降解效果。当阴极电位为-0．7V,pH3．0,铁阳极通电时间20min时,电化学处理200mg／L苯胺480min,TOC的去除效率达到80．4％,矿化电流效率（MCE）为8．6％,显示了该氧化体系具有良好的有机物降解能力。此外,苯胺降解过程中氨氮和硝态氮浓度的变化表明,苯胺分子中的氮主要转化为NH4和NO3^-。     

SBR单级自养脱氮系统氮素转化途径

利用氮素计量关系和批式实验研究了SBR系统中基于短程硝化的单级自养脱氮特性和脱氮途径。结果表明,SBR系统获得良好脱氮效果,TN最高去除负荷和去除速率分别达0.49 kg N/(m3.d)和0.20 kg N/(kg VSS.d);系统中82%的氨氮转化成气体脱除,10%的氨氮转化成硝酸盐氮。批式实验结果表明,SBR系统中的污泥同时具有厌氧氨氧化、亚硝酸盐氧化和自养反硝化活性,三者的反应速率分别为0.12 kg NH4+-N/(kg VSS.d)、0.04 kg NO2--N/(kg VSS.d)和0.03 kg NO2--N/(kg VSS.d)。综上,SBR系统中氮的脱除是短程硝化、厌氧氨氧化和反硝化共同作用的结果,产生的硝酸盐是厌氧氨氧化和硝化作用所致。     

Simultaneous nitrification and denitrification by Pseudomonas sp. Y-5 in a high nitrogen environment

Pseudomonas sp. Y-5, a strain with simultaneous nitrification and denitrification (SND) capacity, was isolated from the Wuhan Municipal Sewage Treatment Plant. This strain could rapidly remove high concentrations of inorganic nitrogen. Specifically, Pseudomonas sp. Y-5 removed 103 mg/L of NH₄⁺-N in 24 h without nitrate or nitrite accumulation when NH₄⁺-N was its sole nitrogen source. The NH₄⁺-N removal efficiency (RE) was 97.26%, and the average removal rate (RR) was 4.30 mg/L/h. Strain Y-5 also removed NO₃^?-N and NO₂^?-N even in aerobic conditions, with average RRs of 4.39 and 4.23 mg/L/h, respectively, and REs of up to 99.34% and 95.81% within 24 h. When cultured in SND medium (SNDM-1), strain Y-5 achieved an NH₄⁺-N RE of up to 97.80% and a total nitrogen (TN) RE of 93.01%, whereas NO₃^?-N was fully depleted in 48 h. Interestingly, high nitrite concentrations did not inhibit the nitrification capacity of Y-5 when grown in SNDM-2, the RE of NH₄⁺-N and TN reached 96.29% and 94.26%, respectively, and nitrite was consumed completely. Strain Y-5 also adapted well to high concentrations of ammonia (~401.68 mg NH₄⁺-N/L) or organic nitrogen (~315.12 mg TN/L). Our results suggested that Pseudomonas sp. Y-5 achieved efficient simultaneous nitrification and denitrification, thus demonstrating its potential applicability in the treatment of nitrogen-polluted wastewater.

     

超声波-膜生物法联合处理垃圾焚烧厂渗滤液

采用超声波-膜生物法(MBR)联合处理垃圾渗滤液,探讨了超声波辐射时间和MBR的水力负荷对COD、NH3-N和TP去除的影响。结果表明,(1)超声波单独处理时,超声波辐射时间在30～90 s时,COD、NH3-N最大增加率分别34.31%、3.36%,而对TP的去除没有影响;(2)超声波-膜生物(MBR)联合处理时,超声波辐射时间为300 s,MBR的水力负荷为6.4 L/(m2.d)时,COD、NH3-N和TP的最佳去除率分别为92.20%、80.10%和91.12%;MBR的水力负荷为12.8 L/(m2.d),超声波辐射时间在5～20 min时,COD、NH3-N的最佳去除率分别为92.34%、79.93%,TP的浓度低于0.2 mg/L;MBR反应时间为7 h,超声波辐射时间为5～20 min,与未进行超声波辐射处理(超声波辐射时间为0 min)相比,COD、NH3-N的去除率增加了11.37%、15.26%;超声波预处理有助于提高后续MBR对COD、NH3-N的去除作用。     

复合沸石滤床修复北方景观水体的实验研究

以天然矿物质沸石、细砂及煤渣取代传统滤料构建复合基质生态床,表面种植景观植物,采用下向流-上向流运行方式修复北方景观水体。分别进行静态实验及不同循环速率下的动态实验,考察对水体污染物去除过程。结果表明,2种运行方式下对水体NH⁺₄-N去除率都在85%以上,其中以1 h为循环周期的运行方式去除率达97%,较静态提高12.8%;TN去除率最高为84%;TP去除不稳定,过程缓慢。煤渣层对NH⁺₄-N的去除效果差,硝化作用不彻底与反硝化作用的加强使下层出水NH⁺₄-N 、NO^-₂-N及NO^-₃-N浓度均高于上层。提高循环速率有利于对氮的去除。     

ANAMMOX与反硝化协同作用及氮素负荷研究

向成功启动并稳定运行630 d后的UASB生物膜反应器系统连续添加有机物,分析其对厌氧氨氧化反应脱氮效果的影响,并进行氮素浓度负荷试验.在厌氧氨氧化反应器系统中连续投加有机COD(葡萄糖),系统运行稳定,有机COD(葡萄糖)存在对系统去除氮素能力影响不大,有机COD去除率达到92.0%,仅用23 d,在同一反应器系统中成功实现了厌氧氨氧化与反硝化协同作用脱氮.氮素浓度负荷试验阶段,进水氨氮(NH 4-N)、亚硝氮(NO-2-N)以及总氮(TN)浓度负荷分别从0.063 kg/(m3·d)和0.063 kg/(m3·d)和0.126 kg/(m3·d)提升到了0.239 kg/(m3·d)、0.315 kg/(m3·d)和0.554 kg/(m3·d),相应去除率分别为84.0%、93.0%和85.0%,厌氧氨氧化工艺的UASB生物膜反应器对氮素浓度负荷仍有很大提升空间.     

A Novel Design for Anaerobic Chemical Oxygen Demand and Nitrogen Removal from Leachate in a Semiaerobic Landfill

Abstract

The removal capacity of carbon and nitrogen from an artificial leachate was evaluated by using laboratory-scale columns, and a design was proposed to remove nitrogen more efficiently from a semiaerobic landfill. Five columns (i.e., two artificial municipal waste columns under anaerobic and semiaerobic conditions, an artificial construction waste column under semiaerobic conditions, and two crushed stone columns under anaerobic and semiaerobic conditions) were used. The influent load rates of organics [g chemical oxygen demand (COD)/m³ ·day], NH₄ ⁺, NO₃ ^?, and aeration conditions for the columns were varied, and the removal capacities of the columns for COD, NH₄ ⁺-N, and NO₃ ^?-N were measured.

Among the packed column materials, crushed stone was shown to be most effective in removing COD, NH₄ ⁺-N, and NO₃ ^?-N from artificial leachate. Average removal rates of crushed column under the semiaerobic condition (column D) for COD and NH₄ ⁺-N were estimated at about 150 g COD/m³·day and 20 g COD/m³ ·day, while those of crushed column under anaerobic condition (column E) for COD and NO₃ ^?-N at about 400 and 150 g COD/m³ ·day, respectively. It also was found that denitrification and nitrification reactions in column D occurred at the same time, and the ratio of denitrification to nitrification was estimated to be about 80%. Therefore, an anaerobic structure, which could be attached to the bottom of a main pipe in a semiaerobic landfill, is suggested to remove nitrogen and organic substances more effectively.     

电催化氧化技术处理制革综合废水

选择DSA电极中的钛基掺硼金钢石膜电极(Ti/BDD),用于制革综合废水的电催化氧化处理研究,考察了在不同的电流密度、电压、电解质、pH值和电解时间等因素对COD去除率和电流效率的影响。结果表明,控制电流密度为30mA/cm2,电压为8.0 V,电解质(NaCl)浓度为2.0 g/L,pH为4.0,电催化氧化处理2 h后,废水的COD和NH4+-N的去除率分别达到了83.6%和90.3%,BOD/COD为0.45,比能耗为35.34 kWh/kg COD,电流效率为37%。     

Treatment of pretreated coking wastewater by flocculation,alkali out,air stripping,and three-dimensional electrocatalytic oxidation with parallel plate electrodes

The coking wastewater generally comprises highly concentrated, recalcitrant, and toxic organic pollutants, so its treatment has been of great importance to prevent living beings and their environment from these hazardous contaminations. The treatment of pretreated coking wastewater by flocculation-coagulation, alkali out, air stripping, and three-dimensional (3-D) electrocatalytic oxidation was performed (gap between the used β-PbO₂/Ti anode and titanium cathode, 12 mm; mass ratio of Cu-Mn/granular activated carbon (GAC) to effluent, 1:4; cell voltage, 7 V). The results showed that the pH adjusting from 3.7 to 6.1 was necessary for coagulants; alkali out played an important role because it brought up precipitation containing higher fatty acids as well as other contaminants to decrease the chemical oxygen demand (COD) in the effluent, and it had also forced the reduction of ammonia nitrogen (NH₃-N) by incorporating with air stripping; for 3-D electrocatalytic oxidation with a bleaching liquid assisting, the initial pH 8.5 of effluent was suitable for Cu-Mn/GAC; moreover, it was considered that its Cu component was dedicated to the decrease of COD and NH₃-N, while the Mn component specialized in the decay of NH₃-N. The residual COD and NH₃-N values in the final effluent with pH 6.5 were 95.8 and 8.8 mg/L, respectively, demonstrating that the whole processes applied were feasible and low in cost.