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1.
ABR反应器结构对水力特性的影响   总被引:11,自引:0,他引:11  
ABR反应器的结构决定了反应器的流态, 从而控制着可能达到的处理效率.为进行反应器结构优化设计, 首次研究了ABR的下、上向流室宽度比、折流板底端距底板距离和折流板折角等结构参数与ABR水力特性之间的关系.厌氧折流板反应器ABR的典型结构由一系列相同结构单元串联组成.反应器的水力特性可通过研究单个单元的水力特性推知.采用停留时间分布RTD (residence time distribution)方法研究了反应器各结构参数的变化对一个5.2 5L的ABR单元清水水力特性的影响.结果表明: ABR的死区较小, 远低于其他厌氧生物反应器; 流态接近理想推流式; 下、上向流室宽度比不宜过小, 最佳值为1∶3;折流板底端距底板距离与死区在本试验所取范围内(1~ 5cm)成正比关系; 折流板折角以50°左右为佳.   相似文献   

2.
厌氧折流板反应器中酸化菌活性研究   总被引:5,自引:0,他引:5  
本实验将厌氧折流板反应器控制在水解酸化阶段,以比INT脱氢酶活性来表征反应器中各室内的酸化菌活性。探讨了各格室酸化菌活性的变化规律,并对影响各室酸化菌活性的影响因素进行了分析。结果表明,在有机负荷2.4 kgCOD/(m3·d) 条件下,反应器中各室酸化率与酸化菌比INT脱氢酶活性成相关性,一室、二室的酸化率占总酸化率的73%;同一格室内比INT脱氢酶活性中部高于底部。  相似文献   

3.
为优化高负荷生物絮凝-膜反应器(HLB-MR)的工艺参数,提高其资源化城市污水的效能,采用平行对比实验,考察了不同固体停留时间(tSR)条件下反应器的有机物去除效率、生物絮凝效果、有机物回收效果和膜污染情况。结果表明:在tSR分别为0.2、0.6、1.0 d时,HLB-MR反应器有机物去除效率均在85%以上,其出水化学需氧量(COD)质量浓度均保持在30 mg/L左右;反应器内的生物絮凝效果随着tSR的延长而增强,其胶体COD絮凝效率从tSR为0.2 d时的66%增加到tSR为1.0 d时的95%,与此同时,有机物的矿化损失率也逐渐增加,从tSR为0.2 d时的6.9%增加到tSR为1.0 d时的10.5%,总COD的回收率逐渐降低;反应器内浓缩液的膜污染潜势随着tSR的延长逐渐缓解,这与较长tSR条件下反应器内胞外聚合物(EPS)产量较高、生物絮凝效果较好、微细颗粒(0~1 μm)的颗粒浓度较低有关。经过综合对比分析,0.6 d为反应器较优的tSR参数,在该条件下,胶体COD的絮凝效率高达90%,膜污染程度较轻;总COD的矿化损失率低至7.4%,总COD的回收率(忽略膜清洗时有机物损失)可高达80%以上。  相似文献   

4.
蛇绿混杂岩是研究洋陆转换、板块构造向板内构造转换过程的关键证据。本文以西藏班公湖蛇绿混杂岩中的硅质岩为研究对象,通过岩石学以及主量、稀土元素地球化学特征研究,分析了硅质岩成因和沉积环境。研究区硅质岩呈夹层产出在沙木罗组或断片产出在玄武岩中,具有隐晶质结构、生物碎屑结构和块状构造,含有晚侏罗世—早白垩世放射虫。硅质岩w(SiO2)为73.80%~90.44%,w(Al2O3)为3.67%~12.33%;MnO/TiO2,Fe2O3/SiO2,Fe2O3/TiO2和Al2O3/(Al2O3+Fe2O3)分别为0.14~0.91,31.44~141.88,1.83~11.80和0.66~0.96;稀土元素北美页岩标准化后显示平坦型稀土配分模式,δ...  相似文献   

5.
高岭土是自然界较常见的无机矿物,对微生物的生长代谢有促进作用,煤中赋存大量高岭土,而有关其对煤生物产气影响的报道确较少。为探究高岭土对煤生物产气的影响,以陕西榆林煤为研究对象,以驯化的微生物作为产气菌群,通过在培养基中添加不同质量分数的高岭土进行煤生物模拟产气,利用气相色谱仪、酶标仪、傅里叶红外光谱仪、Illumina高通量测序平台,研究CH4产量、总挥发性脂肪酸(Volatile Fatty Acids, VFAs)浓度、辅酶F420含量、产气前后煤的有机官能团和微生物群落结构的变化。结果表明:高岭土的添加影响生物产气过程,0~8.0%高岭土添加量可明显分为2个区间,0~1.0%和2.0%~8.0%,产甲烷量、累积产甲烷量和F420在2个区间内呈先升后降趋势,而乙酸和VFAs浓度变化趋势相反;模拟生物产气50 d后,添加高岭土实验组(0.5%)每克煤累积产甲烷量最高可达216 μmol,较空白组提高55.4%;同时,添加高岭土可以提高辅酶F420的含量,最高可达48.93 ng/L,也有助于煤中的醇、酚—OH、—NH—和—NH2被微生物利用。高岭土对煤生物产气体系中细菌种群结构的影响规律不明显,仅Firmicutes(厚壁菌门)在0~1.0%和2.0%~8.0%添加区间呈现先增后减的变化趋势;相比之下,高岭土的添加对古菌丰度变化影响较明显,体系中的古菌主要是Euryarchaeota(广古菌门),其中,Methanosarcina(甲烷八叠球菌属)和Methanobacterium(甲烷杆菌属)是古菌中丰度最高的种属,Euryarchaeota和Methanosarcina丰度在0~1.0%和2.0%~8.0%区间内与甲烷累积产量变化、F420变化趋势一致,Methanobacterium却和VFAs变化趋势一致。由此得出,高岭土的添加会影响榆林煤的生物产气,其产甲烷量、VFAs、F420酶活性、微生物群落结构和煤中有机官能团组成均会发生变化,这为后续研究煤中无机矿物对煤的生物产气的影响提供参考。   相似文献   

6.
三相生物流化床处理啤酒废水   总被引:11,自引:4,他引:7  
通过三相生物流化床处理啤酒废水的实验研究,探讨曝气量和水力停留时间对处理效果的影响,确定最佳曝气量为0.25 m3/h,最佳水力停留时间为1.5 h。在该实验条件下,CODcr平均去除率在85%以上,生物浓度高达28.31 mg/L,生物膜活性强,同时反应器具有较强的抗冲击负荷能力。  相似文献   

7.
活性TiO2的制备与去除地下水中氟离子(F-)性能的研究   总被引:4,自引:0,他引:4  
通过静态和动态(柱)吸附实验,探讨了活性TiO2去除地下水中氟离子(F)时活性TiO2的投加量、处理时间、酸度等影响因素。实验结果表明:在静态实验中,在50 mL,F-浓度为10 mg/L的地下水样中,加入0.3 g活性TiO2,处理15 min,F-的去除率可达90%以上,且处理前后水样的pH值不变。在动态实验中,0.3 g的活性TiO2和120 g砾石可使150 mL水样的除氟率达到90%以上。处理后均可达到饮用水的标准。  相似文献   

8.
大兴安岭东部地区下白垩统龙江组新认识   总被引:3,自引:0,他引:3  
对龙江地区龙江组建组剖面进行了岩石地层、生物地层、同位素年代和岩石地球化学等多方面的研究,重新厘定了龙江组的含义.新义龙江组岩石组合由安山岩、英安岩及其火山碎屑岩、流纹质火山碎屑岩和沉积碎屑岩组成;生物化石属于EosestheriaLycoptera-Ephemeropsis trisetalis热河生物群中期生物化石组合,其中叶肢介化石以Eosestheria opima-E.(Dongbeiestheriaguanghuaensis(丰满东方叶肢介-光华东北东方叶肢介)组合为代表;火山岩的岩石地球化学SiO2含量在59.71%~75.65%之间,具有高Al2O3(12.19%~19.39%)和高Na2O(1.04%~5.24%),较富碱性(Na2O+K2O 3.65%~6.25%)的特点,火山岩属于高钾钙碱性岩系列;轻稀土(LREE)富集.全岩激光40Ar/39Ar同位素年龄等时线年龄值为125.4±1.8 Ma.  相似文献   

9.
生物有效硒是评价土壤中硒对植物供给能力的重要指标,目前,我国缺少测试土壤有效硒的国家标准方法。本文采用了10种不同的化学浸提剂对土壤有效硒进行提取,结果表明,各浸提剂浸提能力大小顺序依次为:NaOH(10.57%)> SOL-Se+EX-Se(8.10%)> AB-DTPA(6.79%)> NaHCO3(4.99%)> K2SO4(4.57%)> KH2PO4-K2HPO4(4.33%)> KH2PO4(3.05%)> SOL-Se(2.28%)> EDTA(1.40%)> NH4F-HCl(1.22%),其中KH2PO4、NaHCO3、SOL-Se、KH2PO4-K2HPO4...  相似文献   

10.
Fenton氧化膜-生物反应器出水中丙烯腈的实验研究   总被引:4,自引:0,他引:4  
采用膜-生物反应器和Fenton氧化组合工艺对丙烯腈废水进行处理。从GC/MS测量结果来看,膜-生物反应器出水中主要物质为2,6双(二甲基-乙基)-4-酚、苯二甲酸和硝基苯二甲酸,均为生物难降解有机物,使出水不能达标。后续Fenton氧化工艺处理膜生物反应器出水,可以使COD含量等指标达到所要求的排放标准。经过膜-生物处理与Fenton法结合的优化工艺,COD去除率达到80%~88%,去除率达到98%,出水水质可达排放标准。Fenton氧化工艺的最佳工艺条件为:pH值为3.4,硫酸亚铁的投加量为700mg/L,双氧水的投加量为600mg/L。  相似文献   

11.
This study focuses on treatment of landfill leachate in column experiments by immobilized Trametes versicolor on polyurethane foam, collected from Nonthaburi landfill site, Thailand. In this study, glucose was used as a co-substrate. The effect of biomass growth on color removal was observed by immobilizing fungi on polyurethane foam. The same immobilized fungi were used for four cycles of 5 days each to find the reuse of fungi. Leachate was diluted to see the effect of organic loading on color removal. At optimum pH of 4 and in 20 days with 3 g/L of glucose, the fungi could decolorize 78 % and 63 % for 5-times dilution and concentrated leachate, respectively, using immobilized fungi after 4 days initial growth. Fungi could also reduce biological oxygen demand and chemical oxygen demand of 52 % and 42 % (with initial biological oxygen demand and chemical oxygen demand of 48,900 and 96,512 mg/L), respectively, with glucose 3 g/L in concentrate leachate and with 4 days initial immobilization of fungi on polyurethane foam. About 1–6% higher color removal was observed on day 20 with 15 days fungi immobilization initially as compared to 4 days immobilization. Higher removal efficiency was observed for the same leachate after dilution due to reduction in organic loading. Addition of co-substrate enhances significantly removal of color, biological oxygen demand and chemical oxygen demand. Chemical oxygen demand removal reached to 0.6 mg/mg of biomass with the co-substrate. Therefore, white rot fungi can be considered as potentially useful microorganisms in landfill leachate treatment.  相似文献   

12.
An activated carbon-impregnated cellulose filter was fabricated, and the capacity to remove dust and volatile organic compounds was evaluated in a laboratory. The adsorption capacities for benzene, toluene, ethyl benzene and m-xylene gases were compared by an adsorption isotherm test conducted as a preliminary test, showing that m-xylene and benzene were the most and least favorable for adsorption onto activated carbon, respectively. Cellulose filters were made with four levels of activated carbon contents, and dust removal was performed with all of the filters showing 99 % and higher efficiencies stable with a small variation during the experiment. Activated carbon content of 5 g in the unit filter area (125 g/m2) was found optimum for benzene, toluene, ethylbenzene and m-xylene removal, as it appeared that higher than 5 g activated carbon content was unnecessary for the improvement of its capacity. With increasing benzene, toluene, ethylbenzene and m-xylene loading, the highest removal rates were determined as 0.33–0.37 mg/cm2 s for as short as 0.0046 s of air filter residence time. The rapid removal was possible because of the high surface area of the activated carbon-impregnated cellulose filter provided by powdered activated carbon, which is distinguished from the granular form in conventional activated carbon towers. As fixed within a cellulose scaffolding structure, the powdered activated carbon performed excellent benzene, toluene, ethylbenzene, and m-xylene adsorption (98.9–100 %), and at the same time, particular matters were removed in average 99.7 % efficiency after being filtered through the cellulose filter sheet.  相似文献   

13.
吗啉废水的生化处理工艺   总被引:2,自引:0,他引:2  
以含有吗啉、甲基吗啉的高浓度有机废水为研究对象,提出了曝气吹脱-吸附-生物处理的联合工艺,并在室内进行了小试实验。结果表明:原废水经过2次曝气吹脱后,ρ(NH3-N)从62 500 mg/L降为431 mg/L,ρ(COD)从50 840 mg/L降为26 051 mg/L。通过吸附实验,ρ(COD)从26 051 mg/L降为2 769 mg/L,ρ(NH3-N)从412 mg/L降为134 mg/L。在生物处理室内小试实验中,采用了活性污泥反应器与曝气生物滤池相结合的处理工艺。在活性污泥反应系统中,当废水pH为7.5、ρ(DO)为4.3 mg/L、水力停留时间为30 h时,COD的去除率最高,可以达到83.1%。在曝气生物滤池中,当ρ(DO)为3.3 mg/L时,COD去除率最高,达到55.8%。在生物处理的最佳参数条件下进行连续监测,当进水ρ(COD)为2 769 mg/L、出水ρ(COD)平均值为387 mg/L时,COD去除率可达到85.9%。吗啉废水经过此联合工艺的处理,ρ(COD)从50 840 mg/L降为387 mg/L。  相似文献   

14.
Endocrine disrupting chemicals are discharged into the environment mainly through wastewater treatment processes. There is a need for better understanding of the fate of these compounds in the unit processes of treatment plant to optimise their removal. The fate of oestrone, 17β-estradiol, 17α-ethinyestradiol and nonylphenol in the unit processes of full scale wastewater treatment plants in the UK, including activated sludge plant, oxidation ditch, biofilter and rotating biological contactor were investigated. The overall removal efficiencies of all the compounds ranged from 41 %to 100%. The removals were predominantly during the secondary biological treatment with the rates of removal related to the nitrification rates and the sludge age. The removal efficiency of the treatment processes were in the order activated sludge > oxidation ditch > biofilter > rotating biological contactors. Activated sludge plant configured for biological nutrient removal showed better removal of the endocrine disrupting chemicals compared to conventional activated sludge plant effluents. Tertiary treatment was also significant in the removal process through solids removal. Overall mechanisms of removal were biodegradation and sorption unto sludge biomass. Phytoremediation was also significant in the removal processes. The endocrine disrupting chemicals persisted in the anaerobic sludge digestion process with percentage removals ranging fro 10–48 %. Sorption of the endocrine disrupting chemicals onto the sludge increased with increasing values for the partitioning coefficients and the organic carbon contents of the sludge.  相似文献   

15.
In this research, physical, chemical and biological treatability of Tehran solid waste leachate was studied. Results indicate that the amount of COD for the fresh raw leachate of Tehran is equal to 66,608 mg/l. The leachate is transferred to an equalization tank for storage and pH control process. After neutralization, leachate is introduced to an up flow and down flow anaerobic reactor. The effluent of anaerobic reactor is conducted to a sequencing batch reactor. Sequence batch reactor (SBR) effluent was pumped in to sand and activated carbon filters, after chemical coagulation and clarification. Results showed that anaerobic reactor with detention time of 3 days had a 35% COD removal and increasing the detention time to 4.5 days would improve the COD removal to 45%. Nutrient adjustment with phosphorus and nitrogen increased the initial 23% efficiency of sequence batch reactor to 44%. The effluent COD of SBR reactor was 21,309 mg/l. Recycling of aerobic reactor effluent with incoming feed to anaerobic reactor reduced the anaerobic reactor influent COD to 20,000 mg/l and this caused 53% and 57% COD removal in the anaerobic and aerobic effluent, respectively. The total systems COD performance increased to 80% and SBR effluent COD eventually reduced to 4,000 mg/l. Coagulation, flocculation and sedimentation processes were practiced to make the 4,000 mg/l effluent COD comply with environmental standards of Iran. The optimum coagulant found to be ferric chloride with the dosage of 50 mg/l at pH of 12, which reduced 10% of COD to an amount of 3,676 mg/l. The effluent was stored in a tank and then pumped in to pressure sand filter and afterwards to activated carbon filter. The COD removal was three and 90% for sand and activated carbon filters, respectively. The total process reduced the remaining COD to 36 mg/l, which is in compliance with environmental standards of Iran.  相似文献   

16.
In this study, the removal of free cyanide from aqueous solutions by activated carbon was investigated. Effects of metal impregnation (Cu and Ag), aeration, and concentrations of adsorbent and cyanide on the rate and extent of the removal of cyanide were studied. The results have shown that the capacity of activated carbon for the removal of cyanide can be significantly improved (up to 6.3-fold) via impregnation of activated carbon with metals such as copper and silver. Silver-impregnated activated carbon was found to be the most effective at the reduction of cyanide level in solution. This appeared to be coupled with its comparatively high metal content after impregnation process where silver (5.07%) could be more readily loaded on activated carbon than copper (0.43%). Kinetics and equilibrium data for cyanide removal by plain and metal-impregnated activated carbons were determined to be consistent with the pseudo second-order kinetics and the Langmuir adsorption isotherms, respectively. Aeration (0.27 l/min) was found to exert a profound effect on the process leading to a 5.5–49.1% enhancement in the performances of plain and metal-impregnated activated carbons. This enhancement could be attributed to the increase in the availability of active sites on activated carbon for adsorption and the catalytic oxidising activity of activated carbon in the presence of oxygen. Practical limiting capacity of plain, copper- and silver-impregnated activated carbons for the removal of cyanide were experimentally determined to be 19.7, 22.4 and 29.6 mg/g, respectively.  相似文献   

17.
The use of suspensions of nanoparticles of titanium dioxide in photocatalytic degradation of dye solution has disadvantages of inconvenient separation of fine particles for reuse and limited penetration of light for effective degradation. These problems can be minimized by supporting titanium dioxide on various inert supports. The present study involves the preparation of immobilized titanium dioxide films by three different techniques and characterization of the prepared films. The immobilized films of nanocrystals of titanium dioxide were prepared using sol?Cgel technique, polyvinyl alcohol?Cformaldehyde binder and acrylic emulsion. The photocatalytic performance of the prepared films for degradation of amaranth dye has also been evaluated and compared. Combination of photodegradation and adsorption processes induces strong beneficial effects on removal of dyes. Addition of high adsorption capacity activated carbon to photoactive titanium dioxide in photodegradation of dyes improves the efficiency of dye mineralization. The activated carbon has also been immobilized along with titanium dioxide in the present work to examine the dual effect of photodegradation and adsorption in the removal of amaranth. The films formed with the help of polyvinyl alcohol?Cformaldehyde binder showed better dye degradation capabilities.  相似文献   

18.
混合PRB介质处理渗滤液污染地下水的可行性研究   总被引:6,自引:0,他引:6  
宗芳  赵勇胜  董军  马莉  李爽 《世界地质》2006,25(2):182-186
反应介质的选择是可渗透反应墙(PRB)系统原位处理污染地下水的一个关键问题。本实验采用两种混合介质A(陶粒与活性炭的混合物)和B(沸石与活性炭的混合物),对修复被渗滤液污染的地下水的可行性进行了研究。结果表明,混合介质A和B对CODCr的平均去除率分别达到了71.8%和63.4%;对NH4 的平均去除率分别为13.5%和58.7%;对重金属的去除,反应介质B则优于A。因此,PRB反应介质的选择要根据污染物的性质而定。  相似文献   

19.
Acid Mine Drainage (AMD) needs to be treated before it can be re-used or discharged in receiving water bodies due to the low pH, high salinity and high sulphate concentrations of the water. Several treatment methods are currently applied including chemical treatment (e.g. neutralisation of the low pH waters), physical treatment (e.g. reverse osmosis) and biological treatment to reduce the high sulphate concentration. When treating AMD biologically, sulphate reducing bacteria (SRB) reduce sulphate to sulphide, provided that a suitable and cost effective carbon and energy source is present. In the present study mine water was remediated biologically, using the degradation products of grass-cellulose, as carbon and energy sources for the sulphate reducing bacteria. A laboratory scale one stage anaerobic bioreactor (20 L volume) containing grass cuttings and biomass consisting of rumen fluid microorganisms and immobilized SRB, was initially fed with synthetic sulphate rich water and later with diluted AMD. The results indicated an average of 86% sulphate removal efficiency when feeding synthetic sulphate rich feed water to the reactor. When feeding diluted AMD, the highest sulphate removal efficiency was 78%. The sulphate removal was dependant on Chemical Oxygen Demand (COD) concentrations in the reactor. Increased COD concentrations were obtained when fresh grass was added to the reactor on a regular basis. Metal removal, especially iron, was observed due to the metal sulphide precipitates formed during biological sulphate removal.  相似文献   

20.
The efficiency of denitrification and enhanced biological phosphorus removal in biological nutrient removal activated sludge systems is strongly dependent on the availability of appropriate carbon sources. Due to high costs of commercial compounds (such as methanol, ethanol, acetic acid, etc.) and acclimation periods (usually) required, the effective use of internal substrates is preferred. The aim of this study was to determine the effects of slowly biodegradable compounds (particulate and colloidal), as internal carbon sources, on denitrification, phosphate release/uptake and oxygen utilization for a full-scale process mixed liquor from two large wastewater treatment plants located in northern Poland. Since it is difficult to distinguish the effect of slowly biodegradable substrate in a direct way, a novel procedure was developed and implemented. Four types of one- and two-phase laboratory batch experiments were carried out in two parallel reactors with the settled wastewater without pre-treatment (reactor 1) and pre-treated with coagulation–flocculation (reactor 2). The removal of colloidal and particulate fractions resulted in the reduced process rates (except for phosphate release). The average reductions ranged from 13 % for the oxygen utilization rate during the second phase of a two-phase experiment (anaerobic/aerobic), up to 35 % for the nitrate utilization rate (NUR) during the second phase of a conventional NUR measurement.  相似文献   

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