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701.
从膨润土中筛选出可在含2 g/L苯酚的PDA培养基上生长的菌种,经过逐级驯化,得到1株可以在1 g/L苯酚的无机盐固体培养基上生长并降解苯酚的优势菌种HJ01,其对苯酚600 g/L降解率可达94%.该菌生长的适宜碳源和氮源分别为蔗糖和NH4Cl,温度为25 ℃,pH值范围为6-7.  相似文献   
702.
Fenton process, as a pretreatment method, was found to be effective in the primary treatment of mature/medium landfill leachate. However, the main problem of the process is the large amount of produced sludge that requires an accurate feasibility evaluation for operational applications. In this study, the response surface methodology was applied for the modeling and optimization of Fenton process in three target responses, (1) overall COD removal, (2) sludge to iron ratio (SIR) and (3) organics removal to sludge ratio (ORSR), where the latter two were new self-defined responses for prediction of sludge generation and applicability assessment of the process, respectively. The effective variables included the initial pH, [H2O2]/[Fe2+] ratio and Fe2+ dosage. According to the statistical analysis, all the proposed models were adequate (with adjusted R2 of 0.9116–0.9512) and had considerable predictive capability (with prediction R2 up to 0.9092 and appropriate adequate precision). It was found that all the variables had significant effects on the responses, specifically by their observed role in dominant oxidation mechanism. The optimum operational conditions obtained by overlay plot, were found to be initial pH of 5.7, [H2O2]/[Fe2+] ratio of 17.72 and [Fe2+] of 195 mM, which led to 69% COD removal, 2.4 (l sludge/consumed mole Fe2+) of SIR and 16.5 (gCOD removed/l produced sludge) for ORSR in verification test, in accordance with models-predicted values. Finally, it was observed that [H2O2]/[Fe2+] ratio and Fe2+ dosage had significant influence on COD removal, while Fe2+ dosage and [H2O2]/[Fe2+] ratio had remarkable effects on SIR and ORSR responses, respectively.  相似文献   
703.
从可持续发展战略出发,阐述了目前我国在工业生产发展中面临的问题。为解决工业发展与保护环境的矛盾,实现社会与自然的协调发展,提出了以清洁生产为主,末端处理为辅,从根本上消除污染,节约原料与能源走发展工业的新路。  相似文献   
704.
Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate.This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m3), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MWe anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems.The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined.The vacuum evaporation process determined a relevant mass reduction of digestate.The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass.Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high concentrations of total Kjeldhal nitrogen (TKN), 55,000 mg/kg as average.Condensate, instead, represented 94.4% of input mass, containing 2.5% of TKN. This fraction could be discharged into surface water, after purification to meet the criteria imposed by Italian regulation. Most likely, condensate could be used as dilution water for digestion input, for cleaning floor and surfaces of animal housings or for crop irrigation.The research showed the great effectiveness of the vacuum evaporation process, especially in the two stage configuration with acidification. In fact, the concentration of nutrients in a small volume determines easier transportation and reduction of related management costs. In full scale plants energy consumption is estimated to be 5–8 kWhe/m3 of digestate and 350 kWht/m3 of evaporated water.  相似文献   
705.
电解法处理含镍废水及纯镍的回收   总被引:1,自引:0,他引:1  
采用电解回收法处理Ni2+含量为2g/L的废水,在阴极回收纯镍。研究了电解电流、极距、NH4Cl浓度、pH值等因素对Ni2+去除率、槽压、阴极能耗的影响,得出最优工艺参数为:温度20℃,电解时间20min时、电解电流300mA,极距15mm,NH4Cl浓度5g/L,pH值8.0,该条件下Ni2+去除率为96.926%,槽压16.21V,阴极能耗22.418kW.h/kg,在阴极可得到沉积6.45μm厚的镍板。  相似文献   
706.
本文研制了一种可用于废水处理的新型阳极和阴极,研制电极电解处理离子染料色模拟液时,分解电压低,脱色率高,电能消耗少。  相似文献   
707.
废弃钻井泥浆的固化处理   总被引:2,自引:0,他引:2  
席建  李进强 《四川环境》1994,13(4):28-31
废弃钻井泥浆的处理是油气勘探与开发工业中人们极为关注的。文章在分析废弃钻井泥浆性质的基础上,通过化学稳定与固化处理试验研究得出以水泥为主,烟炭,石灰等为添加剂的固化剂配方,实验结果表明,经固化处理的废弃泥浆,其固化产物重金属浸出率低,稳定性好,具有一定的抗氧强度,从而能有效地降低废弃泥浆对环境的污染危害,文中还对各种辅加剂对固化效果的影响进行了分析。  相似文献   
708.
用尿素和甲醛作为主要原料合成脲醛树脂季胺盐和脲醛树脂叔胺盐。采用WEMCO浮选模型机和自行设计的模拟现场充气浮选的气浮设备及现场污水对絮凝浮选剂除油、除悬浮物的性能进行了评价。另外,用核磁共振和红外光谱测定了脲醛树脂叔胺盐的结构,并用凝胶色谱法测定了其分子量。  相似文献   
709.
含油污泥的处理与利用   总被引:12,自引:1,他引:12  
石油开采和加工过程中产生的含油污泥,带有有害物质和较高的热值,既需处理又可综合利用,这是一个复杂而又重要的课题。当前,我国含油污泥处理与利用和国外先进水平有较大差距,处理装置技术落后,不配套,多数污泥未进行无害化处理,造成了环境污染和能源资源的浪费。在收集了大量资料的基础上,列举了含油污泥的性质及危害。“九五”期间应积极开展先进工艺设备的引进推广工作,特别在含油污泥的脱水干燥、污油回收和绿化利用上,可推广江汉、中原油田的先进工艺设备,使含油污泥达到无害化乃至变废为宝。  相似文献   
710.
石油工业废弃物处置及其生物治理趋势   总被引:4,自引:0,他引:4  
鉴于我国石油工作者对石油工业废弃物的普遍关注,现在介绍生物治理的基本概念及SPE石油工程师协会中有关含油污泥生物处置的途径及其突出优越性。生物液/固处理工艺(LST)是目前含油污泥处置现场最经济可行的处置方案。这种好氧的LST工艺过程,能够比较充分地代谢和降解石油污泥中的油和脂并大量除去多环芳烃类(PAH)化合物及其它有机化合物,明显地降低了石油废弃物对人、畜的毒害程度。其工艺较简单,操作也简易,凡经此工艺处理后的废弃物不留残毒和后患,因此早已被世界上先进国家的炼油业视为处理含油污泥的有效选择了。石油工业废弃物的生物防治和生物降解工艺较大程度地领先于目前我国现场正在执行的各种处理含油废弃物的处理工艺。  相似文献   
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