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1.
调查了徐州市电磁辐射污染源的状况,分析了其电磁辐射环境质量的现状,并对全市电磁辐射环境质量进行了评价,指出了分析工作中存在的问题,提出了防治对策。 相似文献
2.
通过对富安茧丝绸清洁生产审计的实例分析,总结出了清洁生产审计,增加了企业的经济效益,降低了生产成本,提高了产品质量,减少了污染物排放。 相似文献
3.
简述了循环经济的内涵,分析了江苏建设循环经济的有利条件,归纳了江苏实践循环经济的类型,提出了7个方面的推进建议。 相似文献
4.
本文讨论了高磁分离中磁助凝的机理和作用.该工艺充分利用磁种的磁学特性,从而提高了处理效率.缩短了沉淀时间.延长了工作周期.降低了磁体电耗,改善了出水水质. 相似文献
5.
以苏州高新区为例,指出了主要环境问题,分析了实施循环经济的环境管理现状及不足,并重点提出了实施循环经济的环境管理对策,为开发区按循环经济的规律运行作了有益的探索,也为循环经济的顺利开展提供了科学依据。 相似文献
6.
简要介绍了高盐废水的概念、危害和传统的处理技术,分析了当前高盐废水处理技术面临的瓶颈。在此基础上提出了深井灌注处理高盐废水技术,概括了深井灌注的国内外发展状况,分析了该技术的应用条件和环境风险,讨论了中国采用深井灌注技术处理高盐废水的可行性。 相似文献
7.
一家机械加工厂采用先进的工艺和设备代替落后的工艺和设备,并且撤消了一些工序和对生产车间进行了重新布局,不仅提高了工作效率,而且减少了环境污染,促进了清洁生产,对此,从废水,废气,噪声和废渣四个方面进行了详细评述。 相似文献
8.
以苏州高新区出口加工区为例,分析了实施循环经济的环境管理现状及不足,指出了主要环境问题,提出了实施循环经济的环境管理对策,探索了出口加工区循环经济的运行规律,为循环经济的顺利开展提供了科学依据。 相似文献
9.
介绍了汽车涂装污水的特点,分析了沉淀池在污水处理应用中存在的问题。分析了斜管沉淀池的设计原理和管理使用难点,并结合实际运用对斜管沉淀池的设计参数的设定进行了探讨,最后提出了斜管沉淀池的优化设计方案。 相似文献
10.
环境激素污染严重威胁着人类及动植物的健康。综述了EDCs生物危害,简要介绍了美国、日本和欧盟的EDCs研究工作,分析了中国居民和动植物的EDCs暴露现状,归纳了现有的流行病学调查信息,并针对现状提出了建议。 相似文献
11.
介绍了生物修复石油污染海滩时常用的修复剂类型及其特点.当实验室环境条件能较好控制时,生物强化剂一般是有效的;然而污染现场得出的证据不能表明其对生物降解有促进作用.实验室和现场的研究均表明营养型生物促进剂能有效促进石油的生物降解.水溶性营养易被波浪和潮汐冲刷掉;缓释型营养盐面临的主要挑战是如何控制其释放速率,以保证孔隙水中能较长时间维持理想的营养浓度;亲油型肥料中含有有机碳,有可能在微生物降解石油之前被优先降解.建议根据污染环境的特点选用适合的生物促进剂. 相似文献
12.
本文以天然植物粉F691为原料 ,通过羧甲基化、接枝共聚和曼尼期 (Mannich)三步反应合成出两性天然高分子改性絮凝剂 (CGAAC)。对造纸混合污泥的絮凝脱水性能的研究结果表明 ,在用量为 2 0— 30mg/L范围内 ,CGAAC对造纸混合污泥有较佳的絮凝脱水效果。 相似文献
13.
Goal, Scope and Background Complexing agents are one of the major environmental concerns in electrolytic and chemical surface treatment (ECST) industry;
e.g. the EU reference document on the best available technology (BREF) pays special attention to the usage of EDTA. However,
no comprehensive studies are available on usage of EDTA or other complexing agents or their load to the receiving waters from
ECST industry. In this study, the concentrations of complexing agents were analyzed to get an overview of their usage and
load and also to recognize their relevance in the environmental permitting and compliance monitoring of such facilities.
Methods Complexing agent concentrations of treated waste water samples of 23 ECST plants with vat volume exceeding 30 m 3 was studied. HPLC and GC-MS were used to analyze and identify complexing agent concentrations, ICP-AES to analyze metals,
and TOC to analyse the organic load. The number of the plants in this study equals around 50% of such installations in Finland
subject to environmental permit as the IPPC directive provides.
Results EDTA, DTPA, and NTA were found in 11 samples out of 23 mainly in rather small concentrations. Their annual load to the receiving
waters may be estimated to be 0.3 tons and the total load from Finnish ECST industry can be extrapolated to be up to 1 ton.
Compared to the estimated use of 5–10 tons in the industry this finding is rather low, even though in Finland cast-off treatment
baths are typically delivered to the hazardous waste treatment plants.
Discussion Since the load of complexing agents is rather low, the chemical waste water treatment seems to be either capable of reducing
complexing agent concentrations to some extent or their usage is lower than expected. On the other hand, it is possible that
not all complexing agents were identified from the samples. The metal concentrations and TOC were well hand in hand with concentrations
found in the Finnish environmental database, which proves that the samples were of average quality of the waste water from
the facilities.
Conclusions According to the results, complexing agents cannot be considered as an environmental risk in the ECST industry in Finland;
EDTA concentrations are clearly below PNEC aqua (2.2 mg/l) and the total discharge is very marginal compared to the discharge from the pulp and paper industry. However,
DPTA seems to be as commonly used as EDTA, but also biodegradable NTA was found.
Recommendations and Perspectives Since EDTA has gained plenty of attention in the BREF, DTPA and other, poorly biodegradable complexing agents should also
be taken into account when the BREF is updated within a few years. Also an EU risk assessment report especially for DTPA should
be supplied, since its use is obviously increasing. 相似文献
14.
This study concerns with the development of modified montmorillonites as adsorbents for water treatment. Polymeric aluminium and iron intercalated forms of montmorillonites have been prepared in the absence and presence of an alkylammonium cationic surfactant (Hexdecyl-trimethyl-ammonium bromide, HDTMA). Montmorillonites intercalated with polymeric Al, Fe, Fe/Al (2:1 Fe to Al ratio in solution), possess large N2 Brunauer-Emmett-Teller (BET) surface areas. XRD data also shows trace amounts of illite and plagioclase within the clay materials. Montmorillonites intercalated with HDTMA, polymeric Fe/HDTMA, polymeric Al/HDTMA and polymeric Fe/Al/HDTMA (1:1 metal to surfactant molar ratio in solution) undergo some losses of N2 BET surface areas. Preliminary adsorption studies on phenol have shown that polymeric Al/HDTMA- and HDTMA-only-modified montmorillonites possess a good affinity for phenol, whereas the polymeric Al/Fe modified- and starting montmorillonites have little affinity for phenol adsorption. 相似文献
15.
The purpose of this study was to evaluate photodegradabilities of the following new low-nitrogen chelating agents: N-bis[(carboxymethoxy)ethyl]glycine (compound 1), N-bis[(1,2-dicarboxyethoxy)ethyl]glycine (compound 2) and N-bis[(1,2-dicarboxyethoxy)ethyl]aspartic acid (compound 3). At first photodegradation of these chelating agents as uncomplexed Na-compound 1–3 and Cu(II) complexes were tested, both in lake and distilled water, by exposing them to near-UV region radiation at the range of 315–400 nm. Uncomplexed Na-compounds 2 and 3 were selected to sunlight exposure experiments carried out in lake and distilled water. Compound 3 was also tested in sunlight as Cu and Ca complexes in both solutions. Photodegradation of Na 6-compound 3 in distilled water was studied by exposing it to radiation at the wavelength of 253.7 nm. Photodegradation products were analysed by means of GC-MS (gas chromatography with mass selective detector). The results demonstrated that compound 1 was quite photostable even as Cu complex while compounds 2 and 3 were found to be photodegradable. Over 90% reduction of compound 3 was achieved during one week and 80% reduction of compound 2 in two weeks' time when they were added as Na salt to lake water and exposed to sunlight. Compound 3 as Cu complex degraded totally in the sunlight in less than one week. In the case of compound 3, the degradation rate decreased depending on the counter cation in the order Cu > Na Ca. The study demonstrated that photodegradation of Na6-compound 3 does not result in total mineralization of the compound. A photodegradation pathway for Na6-compound 3 is proposed. 相似文献
16.
Contamination of concrete at various nuclear power plants and spent nuclear fuel reprocessing facilities by radionuclides represents a significant problem for the world's nuclear power industries and nuclear waste management. The present publication summarizes the most recently published data on Electrokinetic Remediation (EK) of various concrete installations and advantageous effects of the combination of EK with different chelating agents. The specific aspects of decontamination of concrete and mortar surfaces are analyzed, such as: (a) effect of chelating agents (EDTA, citric acid), (b) effect of the zeta-potential (zeta) of concrete surface, (c) effects of sorption and complex formation equilibrium, and (d) specific advantages and problems of the electrokinetic decontamination process. The results of laboratory and in situ tests of chelating agent assisted EK removal of radionuclides are reported. It is demonstrated that the correct combination of EK with specific chelating agents can be effectively employed for decontamination of concrete surfaces. 相似文献
17.
This article presents an overview with critical analysis of technical applicability of advanced oxidation process (AOP) in removing chelating agents from aqueous solution. Apart from the effect of metals for chelating agents as a major influencing factor, selected information such as pH, oxidant’s dose, concentrations of pollutants and treatment performance is presented. The performance of individual AOP is compared. It is evident from our literature survey that photocatalysis with UV irradiation alone or coupled with TiO 2, ozonation and Fenton’s oxidation are frequently applied to mineralize target pollutants. Overall, the selection of the most suitable AOP depends on the characteristics of effluents, technical applicability, discharge standard, regulatory requirements and environmental impacts. 相似文献
18.
Massive utilization of bisphenol A (BPA) in the industrial production of polycarbonate plastics has led to the occurrence of this compound (at μg/L to ng/L level) in the water treatment plant. Nowadays, the presence of BPA in drinking water sources is a major concern among society because BPA is one of the endocrine disruption compounds (EDCs) that can cause hazard to human health even at extremely low concentration level. Parallel to these issues, membrane technology has emerged as the most feasible treatment process to eliminate this recalcitrant contaminant via physical separation mechanism. This paper reviews the occurrences and effects of BPA toward living organisms as well as the application of membrane technology for their removal in water treatment plant. The potential applications of using polymeric membranes for BPA removal are also discussed. Literature revealed that modifying membrane surface using blending approach is the simple yet effective method to improve membrane properties with respect to BPA removal without compromising water permeability. The regeneration process helps in maintaining the performances of membrane at desired level. The application of large-scale membrane process in treatment plant shows the feasibility of the technology for removing BPA and possible future prospect in water treatment process. 相似文献
19.
在实验室模拟的条件下,利用从克拉玛依的石油污染土壤中筛选出的4株高效降解菌,以石油烃降解率、脱氢酶活性、呼吸强度、微生物量碳氮和土壤毒性作为评价指标,研究不加生物菌剂不翻耕、不加生物菌剂翻耕、加生物菌剂不翻耕、加生物菌剂翻耕、加固定化菌剂不翻耕和加固定化菌剂翻耕6种不同实验条件对石油污染土壤修复的效果。结果表明,在63 d的修复过程中,加固定化菌剂翻耕实验F组的石油去除率达到了78.7%,比不加生物菌剂不翻耕实验A组的石油去除率提高了49.5%。随着土壤毒性逐渐降低,玉米(Zea mays L.)和赤子爱胜蚓(Eisenia fetida)可以在F组土壤中良好的生长,达到了修复的效果。 相似文献
20.
Background, aim, and scope Anti-tumour agents and their metabolites are largely excreted into effluent, along with other pharmaceuticals. In the past,
investigations have focused on the input and analysis of pharmaceuticals in surface and ground water. The two oxazaphosphorine
compounds, cyclophosphamide and ifosfamide are important cytostatic drugs used in the chemotherapy of cancer and in the treatment
of autoimmune diseases. Their mechanism of action, involving metabolic activation and unspecific alkylation of nucleophilic
compounds, accounts for genotoxic and carcinogenic effects described in the literature and is reason for environmental concern.
The anti-tumour agents cyclophosphamide (CP) and ifosfamide (IF) were not biodegraded in biodegradation tests. They were not
eliminated in municipal sewage treatment plants. Degradation by photochemically formed HO radicals may be of some relevance
only in shallow, clear, and nitrate-rich water bodies but could be further exploited for elimination of these compounds by
advanced oxidation processes, i.e. in a treatment of hospital waste water. Therefore, CP and IF are assumed to persist in
the aquatic environment and to enter drinking water via surface water. The risk to humans from input of CP and IF into surface
water is not known. 相似文献
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