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921.
垃圾渗滤液组合工艺处理技术   总被引:2,自引:0,他引:2  
针对垃圾渗滤液氨氮浓度高、COD浓度高、难降解物质含量高的特点,研究了MAP脱氮-生物处理-混凝组合工艺,考察了不同单元的作用及影响处理效果的因素。试验结果表明,高浓度的垃圾渗滤液经该优化组合工艺处理,污染物的去除率为COD97.5%、BOD599.2%、NH4-N87.2%、E26075.3%。除NH4-N外,其余指标均达到了生活垃圾填埋污染控制标准中规定的二级排放标准值。  相似文献   
922.
微电解法在废水处理中的研究及应用   总被引:15,自引:0,他引:15  
概述了近20多年来国内外微电解法在染料、印染、重金属、农药、制药、油分等废水处理方面的研究应用及进展,对其处理机理进行了分析。微电解法处理速度快、效率高,主要是在处理过程中同时发生吸附作用和电化学还原作用。因此,该法是一种很有实用价值的废水处理方法。为进一步提高微电解的处理效果,提出了目前微电解法应用中存在的几个问题,并初步探讨了今后的发展动向。  相似文献   
923.
通过对广州市城市生活垃圾处理设施的调查及其排放污染物的监测和分析,阐述了广州市城市生活垃圾处理设施的特点,并提出了规范城市生活垃圾填埋场建设、加强垃圾填埋场管理、减少其对周围环境的影响和发展生活垃圾焚烧发电技术等建议.  相似文献   
924.
作为对废物进行无害化处理及资源化利用的特殊企业,废物处理企业在清洁生产中扮演着与其它企业不同的独特角色。废物处理企业不仅作为废物处理和资源化利用的主体在清洁生产中发挥着直接的作用,而且还通过对废物产生源的影响、对废物处理技术和管理经验的开发和实践、以及对废物有关信息的反馈等方式,对废物产生单位的经营和管理部门决策施加影响,从而起到影响和促进清洁生产的作用。  相似文献   
925.
天然沸石的加工技术及其在水处理中的应用   总被引:10,自引:0,他引:10  
论述了天然沸石的吸附、离子交换和催化性能,介绍了沸石的超细粉碎、选矿提纯、化学增白、改性或改型、人工合成和再生等加工技术.从去除有机污染物、去除氨氮、降低氟含量、去除重金属离子、作污水滤料、消除放射性物质等方面回顾了沸石在水处理中的应用.并对应用前景和未来发展进行了展望。  相似文献   
926.
产酸脱硫反应器中碳硫比对群落生态特征的影响   总被引:10,自引:1,他引:9  
通过产酸脱硫反应器处理高浓度含硫酸盐废水的连续流试验,从群落动态的角度研究碳硫比(COD/SO42-)从4.2降低到2.0的过程中,pH值、氧化还原电位(ORP)、碱度(ALK)和末端产物(VFAs)组成、优势种群分布等群落生态特征的变化规律试验证明,在此过程中ORP和ALK提高,而pH值和VFAs中乙酸的分布比例降低,群落类型由高碳硫比稳定型转化为低碳硫比亚稳定型,但仍未改变乙酸型顶极群落的典型特征.  相似文献   
927.
CNT-TiO2 composite is used to activate PMS under UV-light assistance. Superior performance is due to the enhanced electron-transfer ability of CNT. SO4, •OH and 1O2 play key roles in the degradation of organic pollutants. In this work, a UV-light assisted peroxymonosulfate (PMS) activation system was constructed with the composite catalyst of multi-walled carbon nanotubes (CNT) - titanium dioxide (TiO2). Under the UV light irradiation, the photoinduced electrons generated from TiO2 could be continuously transferred to CNT for the activation of PMS to improve the catalytic performance of organic pollutant degradation. Meanwhile, the separation of photoinduced electron-hole pairs could enhance the photocatalysis efficiency. The electron spin resonance spectroscopy (EPR) and quenching experiments confirmed the generation of sulfate radical (SO4), hydroxyl radical (•OH) and singlet oxygen (1O2) in the UV/PMS/20%CNT-TiO2 system. Almost 100% phenol degradation was observed within 20 min UV-light irradiation. The kinetic reaction rate constant of the UV/PMS/20%CNT-TiO2 system (0.18 min1) was 23.7 times higher than that of the PMS/Co3O4 system (0.0076 min1). This higher catalytic performance was ascribed to the introduction of photoinduced electrons, which could enhance the activation of PMS by the transfer of electrons in the UV/PMS/CNT-TiO2 system.  相似文献   
928.
The wastewater from industrial area was treated by EC via Fe and Al electrodes. Cu, Ni, Cr and Zn were highly removed at the first minutes, simultaneously. Pseudo-2nd-order was found to be more suitable for kinetics. Adsorption capacities based on kinetic modeling were observed as Cr>Cu>Ni>Zn. The chemical cost in the case of pH adjustment after EC was less as 3.83 $/m3. It is known that wastewater produced by the metal-plating industry contains several heavy metals, which are acidic in nature and therefore toxic for the environment and for living creatures. In particular, heavy metals enter the food chain and accumulate in vital organs and cause serious illness. The precipitation of these metals is mostly achieved by pH adjustment, but as an alternative to this method, the electrocoagulation process has investigated in this study using iron and aluminum electrodes. The effects of the pH adjustment on removal before and after the electrocoagulation process were investigated, and cost analyses were also compared. It was observed that a high proportion of removal was obtained during the first minutes of the electrocoagulation process; thus, the current density did not have a great effect. In addition, the pH adjustment after the electrocoagulation process using iron electrodes, which are 10% more effective than aluminum electrodes, was found to be much more efficient than before the electrocoagulation process. In the process where kinetic modeling was applied, it was observed that the heavy metal removal mechanism was not solely due to the collapse of heavy metals at high pH values, and with this modeling, it was seen that this mechanism involved adsorption by iron and aluminum hydroxides formed during the electrocoagulation process. When comparing the ability of heavy metals to be adsorbed, the sequence was observed to be Cr>Cu>Ni>Zn, respectively.  相似文献   
929.
• Mechanochemical treatment reduced the calcination temperature for biochar synthesis. • Biochar is converted to graphite after mechanochemical treatment. • Biochar was reduced to nanoscale after mechanochemical treatment. Biochar (BC) has been extensively studied as adsorbent for the treatment of water pollution. Despite the distinct advantages, the high calcination temperature and low adsorption capacity of pristine BC limit its practical applications. Most of the former studies focused on the structure and/or surface modification to improve the adsorption capacity of BC. However, the harsh experiment conditions involved in the biochar modification limited the application in industrial level. Herein, we introduced mechanical treatment into BC preparation to reduce the calcination temperature and improve the adsorption capacity simultaneously. The results indicated that the calcination temperature was reduced and the adsorption capacity of the treated BC was improved after mechanochemical treatment. Characterization of the samples disclosed that BCs were graphitized with the particle size reduced to nanoscale after treatment. Adsorption tests indicated that the mechanochemically treated BCs showed much better removal performance of organic contaminants than that of pristine BCs. For instance, among four pristine BCs (BC600, BC700, BC800, and BC900), only BC900 has strong adsorption capacity for MB, while BC600 has low adsorption capacity (1.2 mg/g). By comparison, the adsorption capacity of MB increased greatly to 173.96 mg/g by BC600-500/1 (treated at 500 r/min for 1 hour). To optimize the mechanochemical treatment, the effects of rotation speed and agitation duration were also investigated.  相似文献   
930.
本文围绕好氧触媒在造纸法再造烟叶污水处理中的应用展开分析。如对好氧触媒在再造烟叶污水处理中的应用必要性及好氧触媒作用原理予以介绍,并对好氧触媒在造纸法再造烟叶污水处理中应用展开试验。  相似文献   
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