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1.
湿法稀土清洁生产工艺研究   总被引:1,自引:0,他引:1  
对某稀土湿法冶炼工艺进行了清洁生产主案研究,结果表明,精矿REO浸取率由90%提高到97%,从酸浸废液中年回收硫酸亚铁3000t;从碱转废液中年回收硫酸钠3000t;废吕中氟回收率86%;生产废话水排放量削减58%,废水污泥量削减90%;经济效益年200万元以上。  相似文献   

2.
粉煤灰的有效利用   总被引:6,自引:0,他引:6  
介绍了我国粉煤灰利用状况及政策,结合实例分析了粉煤灰的有效利用和清洁生产对促进粉煤灰有效利用的作用。  相似文献   

3.
粉煤灰对脱硫用石灰石溶解特性的影响研究   总被引:2,自引:1,他引:2  
石灰石-石膏湿法烟气脱硫是我国广泛应用的脱硫技术,其中石灰石(CaCO3)活性对优化脱硫装置的设计,降低脱硫成本,提高脱硫效率显得尤为重要。通过实验对CaCO,活性进行了研究,在固定pH值的条件下,采用酸滴定CaCO3浆液的方法,研究了不同pH值以及粉煤灰对CaCO3溶解率的影响。结果表明,在所测的pH值范围内,较低的pH值有利于CaCO3的溶解,pH值每降低0.5,CaCO3的溶解率增加8%左右。但为了保持吸收溶液的脱硫效果,一般选择pH值=5.0~5.5之间。粉煤灰对石灰石硫酸溶解的影响较小,初始2h内粉煤灰对CaCO3的溶解有较大的促进作用,2h后变为微弱的阻碍作用。  相似文献   

4.
对抚顺矿业集团引进国外新的油母页岩加工技术,从生产成本、工艺技术、吨产品能耗物耗、污染物产生和排放等方面进行了对比分析,得出该技术清洁生产水平国内先进的结论。  相似文献   

5.
阐述了湿法气浮处理粉煤灰废水的原理、工艺流程、工艺参数、主要设备等,列举了该方案投产后的成本和效益.  相似文献   

6.
随着社会不断的发展和进步,人们的综合预防环境保护策略的可持续应用在生产过程和产品中的意识也越来越高。经过实行清洁生产,不但能够降低甚至能够达到彻底的消除它们可能够对人类及环境危害的可能性,并且可以节省许多的能源、治理的费用、减轻废物处理、节约材料,这样可以减少生产的基本资金、提高生产的质量和效率,以此来提高产品在市场上的竞争能力。清洁生产可以推动环境影响评价的深入研究和探索,以此来防止环境影响评价缺少可靠性和有效性。本文就清洁生产的内在涵义、环境音响评价中清洁生产的要点分析及环境影响评价中清洁生产分析的方法等进行论述。  相似文献   

7.
第三产业清洁生产方案的研究   总被引:2,自引:0,他引:2  
通过第三产业中宾馆饭店、旅游景点、学校等试点单位开展清洁生产的具体措施,分析了第三产业清洁生产的特点、标准规范,提出可操作的第三产业实施清洁生产的程序方案.  相似文献   

8.
粉煤灰生产铝硅合金的新技术   总被引:1,自引:0,他引:1  
本文简要叙述炉渣粉煤灰生产铝硅合金的工艺技术、理论根据和现实性。  相似文献   

9.
去年太湖蓝藻的爆发,导致太湖流域实施了更加严格的污水排放标准。针对太湖流域印染企业大规模采用的污水厂提标改造的末端治理方法,指出了清洁生产才是面对"新标"的根本解决办法,介绍了印染行业实施清洁生产的新方案和途径,并以某印染企业为例,从无/低费用和中/高费用清洁生产方案两个方面说明了环境保护和经济效益的双赢,为太湖流域其他印染企业的改造提供借鉴。  相似文献   

10.
以禾友化工有限公司清洁生产审计为例,根据市场的需要,适时的实施产品转型的策略,在提高资源的利用效率、降低生产成本和能耗、降污等方面产生明显的效果,进而提高了经济效益和环境效益。  相似文献   

11.
清洁生产是依靠科技进步,改进技术而得到的清洁生产过程,通过清洁生产可以获得清洁的产品。讨论了在中国现阶段实施清洁生产的必要性;分析了清洁生产在中国实施的意义。  相似文献   

12.
Land disposal of fly ash (FA) and sewage sludge (SS) is a major problem due largely to their potentially harmful constituents. Combined use of FA and SS however may help reduce the associated pollution potential. In this paper we summarize the results of several case studies designed to assess the feasibility of land application of FA with and without SS. A wide range of application rates was tested under laboratory, greenhouse and field conditions. The leaching of metals from soil columns amended with moderate rates of FA applications (8-16 Mg ha−1) generally had no significant impact on the metal content of leachate or their downward migration in the soil. The application of FA or SS at a much high rate (74.1 Mg ha−1) significantly increased both leaching and downward migration of metals. The use of 1:1 FA+SS mixture at 148.2 Mg ha−1 reduced metal leaching compared to the combined metal quantities leached when FA or SS applied at 74.1 Mg ha−1. The results indicate that combined use of FA and SS at a rational rate of application should not cause any significant effect on drainage water quality. Plant studies conducted using FA and SS mixtures indicated that these materials could be beneficial for biomass production, without contributing significant metal uptake or leaching. The application of FA as high as 560 Mg ha−1 in a long-term field trial had no detectable deterioration in soil or groundwater quality and no substantial increases in plant uptake of metals and other trace elements were observed. Low to moderate rates of FA and SS therefore could be successfully used as soil amendments, particularly so when used as a mixture.  相似文献   

13.
改性粉煤灰吸附对硝基苯酚的研究   总被引:15,自引:2,他引:15  
研究了粉煤灰 (FA)和浸渍粉煤灰 (IFA)吸附水溶液中有害的对硝基苯酚 ,试验了颗粒大小、浸渍条件、p H值和温度等因素对吸附量的影响。结果表明 ,在稀溶液中进行吸附时 ,提高温度、减小粒径和 p H值 ,可增加粉煤灰对对硝基苯酚的吸附量 ;用 Al3+离子浸渍的粉煤灰具有较大的吸附量 ;吸附机理是多孔物质吸附和静电共同作用的过程。  相似文献   

14.
The metal finishing industry is water intensive. Surveys of South African metal finishing companies indicate that water consumption is as high as 400 L/m2 of metal surface treated, whilst best available practice can achieve less than 10 L/m2. The industry uses hazardous chemicals such as chrome VI, cadmium, nickel and cyanide. If consumption of these chemicals can be optimized, quantities of heavy metals released into the environment will be reduced. In some cases where cleaner production techniques were applied by local companies, heavy metals have been completely eliminated from effluents discharged to municipal sewers, which represent a significant benefit to the urban environment. This benefit was accompanied by significant reduction in the use of chemicals, with a concomitant cost saving and competitive advantage to the companies concerned.A Danish environmental aid initiative promoted cleaner production in the South African metal finishing industry. Local consultants were trained by Danish experts in this field. The general methodology was to conduct an audit of the chemical, water, human resource and environment aspects of the company and compare it to best available practice. Once the review was completed, a detailed feasibility was performed on systems and equipment required to reduce chemical consumption, water consumption, human resources and environmental impact. Applied to a number of South African companies, these methods have typically achieved reductions of the order of 90% in water use and 50–60% in the use of chemicals.There were difficulties in applying the Danish methodology to South African metal finishing companies, as it makes use of quantitative indices derived from the process operations. The companies are often small and technically unsophisticated, and do not have ready access to the process data that are needed. An alternate system is required to simplify the evaluation and optimization process. This paper proposes a case study on a fuzzy-logic operator based evaluation system that outputs the cleaner production status of the company. The model is compared to an established cleaner production tool.  相似文献   

15.
以南方某稳定化飞灰填埋场为研究对象,通过钻孔获取了新鲜、1、3、6和11个月等5个龄期的试样,并在实验室开展了颗粒分析、含水量、持水量等测试.不均匀系数Cu > 5,曲率系数Cc<1,属于级配不良土,容易形成优势流通道.含水量介于18.6%~46.4%之间,随埋深的增大而减小,随龄期的增长而增大.持水量介于15.0%~52.4%之间,随上覆应力的增大而减小,随龄期的增长而增大,由此建立了持水量计算模型.对于相同龄期和埋深的稳定化飞灰,其含水量要低于持水量2.6%~13.7%,这表明稳定化飞灰整体上未达到持水量状态,由此推测底部导排层收集到的渗滤液主要由雨水入渗后经过稳定化飞灰体内优势通道而进入导排层.在此基础上,建立了考虑填埋进程、降雨入渗量、优势流通道、稳定化飞灰产/吸水量等因素的填埋场渗滤液产量预测模型,并利用现场记录数据对模型进行了参数率定.模型分析结果表明,填埋场开始运营后的9个月内,渗滤液主要来源于降雨入渗量和运输车辆冲洗水量,分别占比约48%和52%.当稳定化飞灰体内优势流通道占总孔隙的比例从0%增至20%,导排层收集到的渗滤液量占渗滤液总收集量的比例从0增至34.1%.因此,建议对稳定化飞灰进行充分压实后再填埋,以减少优势流现象的发生,同时改用节水型车辆冲洗装置,最终降低渗滤液总产量.上述研究成果能够为我国类似稳定化飞灰填埋场中导排系统、调节池等的设计提供重要参考.  相似文献   

16.
洁净型煤技术及推广应用探讨   总被引:1,自引:0,他引:1  
洁净型煤的推广使用是有效控制煤烟型污染的一种重要手段,采用在原煤中添加化学药剂,重新加工成型的方法,达到降尘、固硫、节能的目的。通过推广使用,有效的降低二氧化硫、烟尘的产生量和排放量,减少对城市大气环境的污染,达到煤的热量高效、清洁利用。  相似文献   

17.
Various cleaner production (CP) audits have been conducted in the South African metal finishing industry. These studies have been successful in effecting changes to the general status of the local metal finishing industry. In this paper, the initiatives undertaken by a Danish government sponsored project are detailed. The project included the conducting of in-plant assessments, using a tailor-made tool for CP benchmarking. Details on this tool's operations and typical results are presented. Typical assessments indicated potential water savings of 78%, with chemical savings of approximately 30%. The plant modifications undertaken in order to achieve the CP objectives, are described. The affects of these initiatives on local municipal wastewater treatment works are detailed with specific reference to significant reductions in incoming wastewater-borne heavy metals. The main challenge for companies has been data retrieval for the tool and overcoming social barriers for implementing the improvement options. Recommendations include redesigning the assessment tool.  相似文献   

18.
随着生活垃圾焚烧技术的普及,垃圾焚烧飞灰的资源化利用迫在眉睫,然而飞灰中的高浓度氯元素严重阻碍了其资源化进程.水洗技术作为常用的脱氯除盐技术,得到越来越多的应用,但除氯效果受飞灰自身性质特征影响较大.本研究从重庆和天津采集了两种理化性质具有较大差异的垃圾焚烧飞灰,在对其粒径分布、化学组成、矿物组成、pH值和浸出毒性等基本特征进行分析表征的基础上,采用水洗技术和碳酸化水洗技术对两种飞灰进行了脱氯处理.结果表明,重庆飞灰氯元素的赋存形态包括NaCl、KCl等可溶性氯盐,还含有较高浓度的难溶氯盐(如CaClOH、Friedel盐和Ca6(CO3)2(OH)7Cl),因此,水洗技术难以达到理想的脱氯效果,氯盐去除率最高为88%.在水洗过程中通入CO2可以显著降低反应体系的pH值,促进难溶盐的转化和溶解,进而提高飞灰氯盐的去除率.重庆飞灰采用加速碳酸化水洗技术,氯盐去除率最高可达94%.天津飞灰中氯元素主要以可溶性氯盐的形式存在,难溶盐占比很少,因此,水洗技术可以达到较高的脱盐率(96%).采用加速碳酸化技术对天津飞灰进行处理,发现氯盐去除率较纯水洗技术反而有所降低,分析其主要原因可能与加速碳酸化过程中碳酸钙等物质的再沉淀对氯盐的裹挟作用有关.由此可知,飞灰自身性特征尤其是氯盐的赋存形态对于脱氯除盐技术的选择有重要影响.因此,实际资源化利用过程中,可根据飞灰性质来决定预处理手段,从而最大化提升效率和节约成本.  相似文献   

19.
垃圾焚烧飞灰的熔融特性研究   总被引:4,自引:0,他引:4  
以飞灰从开始熔融到熔渣全变成液体这一过程中的4个温度段所得到的熔渣为研究对象,探讨了它们的外观结构、成分、浸出毒性以及液固比、浸取液的pH值对熔渣中Ba、Cd、Ni等重金属浸出量的影响规律.结果表明:飞灰开始熔融后,随着温度的升高,熔渣的颜色逐渐变深、质地逐渐变硬、玻璃化现象逐渐明显,Ca、Al、Mg、K、Fe等主量元素的质量百分含量逐渐升高;熔融温度在1230℃以上所得到的熔渣不再是具有浸出毒性的危险废物;液固比对Ba、Zn、Cd和Ni的浸出量影响较大,而对As的影响较小;Ba、Cu、Pb和Zn等重金属元素在强酸和强碱环境下比较容易浸出.  相似文献   

20.
生活垃圾焚烧飞灰生物脱氯机制研究   总被引:1,自引:0,他引:1  
垃圾焚烧飞灰中的高氯含量是限制其在水泥工业中资源化利用的重要因素,如何实现垃圾焚烧飞灰的有效脱氯是飞灰应用于水泥工业亟需解决的关键技术问题.在对我国7个典型垃圾焚烧厂飞灰组成及特征分析的基础上,开发了飞灰与污泥共处置脱氯工艺,结果表明,我国典型生活垃圾焚烧厂飞灰氯含量达4.6%~12.7%;不同地区焚烧飞灰中氯含量差异性比较明显,主要原因是不同地区垃圾组成不同,其中工业垃圾是飞灰中不可溶氯的主要来源之一;对比水洗前后飞灰同步辐射X射线衍射分析结果,飞灰中可溶氯主要以KCl、NaCl、CaClOH形态存在,不可溶氯主要以AlOCl形态存在;飞灰与污泥按质量比8:2混合,并共处置150d后,飞灰氯含量由14%降低至0.03%,满足我国《通用硅酸盐水泥》(GB175-2007)标准所规定的水泥氯含量不高于0.06%的要求;飞灰与污泥共处置发酵产酸使得混合体系pH值降低,促进飞灰中不可溶氯盐向可溶性氯盐转化是飞灰生物脱氯的主要机制.  相似文献   

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