【作者】 刁炳祥；

【导师】 奚旦立；

【作者基本信息】 东华大学 ， 环境工程， 2010， 博士

【摘要】 电镀污泥是制造业对金属表面处理废液进行集中处理后产生的污泥。由于它含有种类和浓度各不相同的镍、铬、锌、铅、铜等重金属离子,随意弃置将对土壤等环境产生较大危害,威胁动植物和人类健康。所以,我国将电镀污泥列入《危险废物名录》,作为危险废物的一种实施严格的监督管理。随着发达国家制造业陆续向我国转移,我国电镀污泥的产生量越来越大。其产生量之巨大,已成为重点危险废物产生源之一。据不完全统计,目前上海市每年产生的电镀污泥超过2万吨。而且,多数不能进行回收的电镀污泥必须安全处置。即使少数浓度高、来源单一的电镀污泥进行重金属离子等的回收后,残余物仍要作为电镀污泥安全处置。若按要求对电镀污泥实旌安全处置,费用可观。作为电镀污泥临时安全处置的一种替代办法,把电镀污泥掺入粘士中制砖。虽然这种做法对毒性浸出指标是否达标一直存在争议,但它在一段时间内解决了电镀污泥去向的燃眉之急。随着国家政策的调整,有限的土地资源被依法保护,像上海市等一些我国经济发达地区,已禁止烧制粘土砖。就目前全国各地的实际来看,危险废物的安全处置设施尚不健全,绝大多数省市和地区还没建成符合危险废物安全处置要求的处置硬件设施。即使具备了对电镀污泥的处置能力,每吨近2000元的安全处置价格也会让多数企业望而却步。电镀污泥的去向已经成为当前必须亟待解决的问题。在上海市,长期以来作为建筑材料被综合利用的粉煤灰,受建筑规模周期和金融危机的影响,也变得多余;而石洞口、竹园和白龙港等污水处理厂污水生化处理技术的陆续上马,产生的大量活性污泥也亟待寻找合适的处置去向。因此,本研究具有很强的现实意义。本研究以节能减排和循环经济理念为指导,寻找以电镀污泥为主,包括粉煤灰、活性污泥等其他固体废物在内的利用出路为出发点,把需要付费处理的“废物”变为可产生经济效益的产品原料。在对电镀污泥、粉煤灰、活性污泥和陶粒制作等基本特性初步研究的基础上,分析将前面三种原料研磨后混合,作为焙烧陶粒原料的可行性。通过实验研究,以陶粒筒压强度为主要指标,首先找出三种原料焙烧陶粒的最合适配比。在此基础上,运用正交试验,找出焙烧陶粒的最佳预热温度和预热时间,焙烧温度和焙烧时间,并分析其筒压强度、表观密度和吸水率等指标。再引入广西白泥,测试在最佳原料添加比例下,不同焙烧环境条件对烧成陶粒的指标影响。最后,把实验焙烧的两种陶粒引入生产实践。通过常见的几种不同生产工艺条件比较,选择出适合所研制陶粒的生产工艺,并对生产粉煤灰陶粒、电镀污泥粉煤灰陶粒和添加了广西白泥后的电镀污泥粉煤灰陶粒进行经济效益分析,从而得出初步结论和建议。掺混电镀污泥焙烧陶粒研究的主要内容是:第一,关于电镀污泥或由电镀污泥焙烧成的陶粒的浸出毒性是否符合《危险废物鉴别标准—浸出毒性鉴别》(GB5085.3-2007)要求,这是决定电镀污泥是否能够被再利用的关键问题。第二,在原料中掺混电镀污泥制作陶粒的可能性,因进行尝试时鲜有现成的经验可以借鉴,在研究之初能否成功没有把握。第三,考查焙烧环境条件变化对陶粒的影响。要研究不同原料添加比例,不同预烧温度和时间,不同焙烧温度和焙烧时间变化对陶粒烧成参数的影响,以便于对焙烧条件进行合理取舍。第四,运用正交试验优化陶粒的烧制条件。由于原料配比、预烧温度和时间、焙烧温度和时间等影响烧成陶粒的因素较多,需引入正交试验来完成。第五,对使用不同添加剂的试验结果进行对比分析。在电镀污泥和粉煤灰材料基本保持不变的情况下,增加广西白泥作为添加剂进行陶粒焙烧。通过对比分析,得出不同添加剂对陶粒性能的影响。第六,进行生产工艺选择和经济效益分析。研究将添加电镀污泥的陶粒制作引入实际生产需要什么工艺,又能够产生什么样的经济效益,使研究能更好地为生产实践服务。论文是采用电镀污泥、粉煤灰等原料进行焙烧陶粒的应用性研究。在研究过程中具体采用了多种研究方法。前期主要以调查研究和访问研究为主,后期主要以实验性研究为主。在对陶粒焙烧原料的基础研究中,运用内容分析法,对搜集到的各类原料及陶粒产品的特性进行认真分析,对其特性有一定的认识。在后期的实验研究中,具体运用了观察研究法对焙烧陶粒的外观特性进行分析研究;并运用个案研究法对不同配比和环境条件下焙烧的陶粒进行分析,并结合相关研究法将其与其他配比和环境条件下焙烧的陶粒进行对比。再结合定性研究对焙烧陶粒的筒压强度、吸水率和表观密度数据进行定量分析,得出最好的原料配比和焙烧环境条件。最后,再运用比较分析法,对不同生产工艺和原料生产陶粒的经济收益情况进行定量比较。通过本论文的研究,得出以下主要结论:1、在粉煤灰中掺混电镀污泥、活性污泥是能够烧成陶粒的。能够焙烧陶粒的原料有多种,其中起决定作用的主要是原料中氧化硅和氧化铝的含量比例。当两者含量达到80%以上时,就初步具备了焙烧陶粒的基本条件。研究表明,常规粉煤灰中二者的含量是高于这一比例的。电镀污泥和活性污泥中也含有这两种物质,同时还含有其他多种金属离子。在粉煤灰中加入适当比例的电镀污泥和活性污泥后,一方面,可以保持氧化硅和氧化铝的制成陶粒的含量,另一方面,其中的重金属离子还可以起到催化作用,不但能增强陶粒的强度,还能提高陶粒的焙烧速度。在此后的实验中印证了理论上的判断。2、不同的原料配比对焙烧陶粒的强度等指标产生较大的影响。试验中,为了测试不同原料配比对焙烧陶粒指标的影响程度,分别配置X、Y、Z三组不同原料比例的样品,每组包含4个样品。粉煤灰的添加比例在55%-85%之间变化:电镀污泥的添加比例在0%-40%之间变化;活性污泥的添加比例在5%-15%之间变化。结果显示,不同原料配比焙烧出的陶粒颜色差别较大;陶粒强度相差达15.5倍之多。使陶粒强度最大的配比是电镀污泥:粉煤灰:活性污泥=10:80:5。3、运用正交试验,寻找焙烧陶粒的最佳环境条件。试验表明,除原料配方对陶粒强度等指标产生较大影响外,不同的预热温度、预热时间、焙烧温度和焙烧时间等因素对陶粒的烧成也产生较大影响。为了找到最佳焙烧条件,引入正交试验进行筛选。正交试验中第10号样品焙烧的陶粒强度最强,筒压强度为4.526MPa,电镀污泥陶粒的其他指标等均达到优等品标准;含水率为27.3%。当4个因素指标分别达到预热温度700℃、预热时间为15min、焙烧温度为1200℃、焙烧时间为30min时,能够烧制出筒压强度最强的陶粒。4、原料中添加了广西白泥后,陶粒变化指标明显,筒压强度明显增强。添加广西白泥的目的就是观察陶粒指标的变化并将其与没有添加广西白泥的电镀污泥陶粒进行比较,丰富焙烧电镀污泥陶粒的配方和选择。试验分为两组,每组32个试验。广西白泥的添加比例保持20%不变,电镀污泥的添加比例变化幅度为20%.35%,活性污泥为10%-15%,粉煤灰为30%-50%。结果显示,陶粒的吸水率相差高达6993.5倍。与未添加广西白泥的电镀污泥陶粒相比,陶粒的筒压强度普遍增强,样品中最高的达10.35MPa的高强陶粒等级水平。添加广西白泥的最佳配料比和最佳焙烧环境条件是:电镀污泥含量30%,粉煤灰含量40%,活性污泥含量10%,广西白泥含量20%;预热温度600℃,预热时间15min,焙烧温度1175℃,焙烧时间25min。5、选择制作电镀污泥陶粒的生产工艺并进行经济效益分析。通过比选,选择烧结机烧结工艺。生产1m~3陶粒获毛利润分别为,粉煤灰陶粒20.5元,电镀污泥陶粒160.125元,添加广西白泥的电镀污泥陶粒503.125元。说明焙烧电镀污泥陶粒经济效益明显。本研究表明,掺混电镀污泥焙烧陶粒前景广阔。更多还原

【Abstract】 Electroplating sludge refers to the sludge produced by manufacturing industry after concentrated disposal to the metal surface waste liquid. Since it contains various heavy metal ions in different types and concentrations such as Nickel, Chromium, Zinc, Lead and Copper, casual abandonment will bring about great hazard to the soil and threaten the animals, plants and human health. Therefore, China has listed electroplating sludge into the Hazardous Waste List and implemented strict supervision and management as a kind of hazardous waste. With the constant transfer of manufacturing industries from developed countries into our country, China has had an increasing production volume of electroplating sludge which has thus become one of the major hazardous waste sources. According to an incomplete statistics, more than 20,000t electroplating sludge will be produced in Shanghai each year. And most irrecoverable electroplating sludge must be disposed safely. Even though a small amount of electroplating sludge featured as high concentration and single source has been recovered with heavy metal ion, the residue shall be disposed safely as the electroplating sludge. The expense of safety disposal is considerable. As a substitute method of temporary safety disposal, the electroplating sludge shall be mixed into clay for brick fabrication. Although this method is still contraversial to standard accordance of toxicity extraction index, it has settled the urgent orientation of electroplating sludge within a short period of time. With the adjustment of national policies, limited land resources are protected by law. It has been prohibited to calcinate clay bricks in some developed areas in China such as Shanghai. According to the current actual conditions in various areas of the country, safety disposal facilities of hazardous waste are far from complete. Most of the provinces, cities and regions have not established disposal hardware facilities in accordance with the safety disposal requirements of hazardous waste. In spite of disposal ability to the electroplating sludge, the safety disposal price of 2000 Yuan/ton will stop most of the enterprises. The orientation of electroplating sludge has become the urgent problem requiring for immediate solution.At the same time, coal fly ash utilized as construction material for a long time in Shanghai has become abundant under the influence of construction scale, circulation and financial crisis; but the sewage water biochemical disposal technologies in Shidongkou, Zhuyuan and Bailonggang sewage water disposal plants have produced huge amount of active sludge which requires for proper disposal orientation. Therefore, this research has a great realistic significance.Based on the above facts, this research has followed the guidance of energy-saving, discharge reduction and circulation economic principle, searched for the starting point of utilization direction mainly using electroplating sludge and including other solid waste such as coai fly ash and active sludge and changed "waste" requiring for paid disposal into product raw materials that can bring economic benefits. On the basis of initial research to the basic features of electroplating sludge, coal fly ash, active sludge and ceramisite fabrication, the feasibility of grinding and mixing above three raw materials as the raw material of ceramisite calcination shall be analyzed. The experimental research shall be conducted with ceramisite cylinder pressure as the main index to first find out the most suitable mixing ratio of ceramisite calcination with three raw materials. The orthogonal test shall be conducted on such a basis to find out the optimal pre-heat temperature and time of ceramisite calcination, optimal calcination temperature and time and analyze the cylinder pressure strength, surface density and water absorption rate. Then Guangxi white mud shall be utilized to test the index influence of different calcination environmental conditions on the ceramisite calcination under the best raw materials adding proportion. Finally, two calcination ceramisite shall be introduced into the production practice. Several frequently utilized and different production technical conditions shall be compared to select the production technique suitable to the researched and fabricated ceramisite. Besides, economic benefit analysis shall be conducted to the production of coal fly ash ceramisite, electroplating sludge coal fly ash ceramisite and the electroplating sludge coal fly ash ceramisite added with Guangxi white mud with the view to gain initial conclusion and suggestions.Generally speaking, this thesis has mainly researched into the following content: first, identify whether toxicity extraction of ceramisite calcinated by electroplating sludge or electroplating sludge accords with relevant requirements of Identification standards for hazardous wastes-Identification for extraction toxicity (GB5085.3-2007). This is the critical issue in deciding the re-utilization of electroplating sludge. Secondly, identify the possibility of ceramisite fabrication by mixing electroplating sludge into the raw materials. Since very few existent experiences can be borrowed during the attempt, there is both chance of success and failure. Thirdly, the influence of calcination environmental changes on ceramisite shall be investigated. The influence of changes in different raw materials adding proportion, different pre-calcination temperature and time, different calcination temperature and time on the ceramisite calcination parameters shall be analyzed to reasonably take or eliminate calcination conditions. Fourthly, the orthogonal test shall be conducted to optimize the ceramisite alcination conditions. Given numerous elements affecting the ceramisite calcination such as raw materials adding proportion, pre-calcination temperature and time and calcination temperature and time, the orthogonal test shall be conducted to complete the task. Fifthly, a contrast analysis shall be conducted to the test results using different additives. Under the condition of basically unchanged electroplating sludge and coal fly ash materials, Guangxi white mud shall be added as the additive for ceramisite calcination. The influence of different additives on ceramisite performance can be obtained through this contrast analysis. Sixthly, production technical selection and economic benefit analysis shall be conducted. Research shall be made into concrete techniques in introducing ceramisite fabrication (adding electroplating sludge) into the real production and concrete economic benefits to enable research to better serve the production practice.This thesis refers to the applicability research into ceramisite calcination by adopting raw materials such as electroplating sludge, coal fly ash and so on. Numerous research methods have been adopted in the concrete research. Investigation and visit researches are the main form at the initial period while experimental research has been made adopted in the late period. The content analytical method has been adopted in the basic research of ceramisite calcination raw materials to seriously analyze the features of various collected raw materials and ceramisite product to have certain knowledge. In the late period experimental research, observation research method has been adopted to analyze and research the appearance features of ceramisite calcination; and individual research method has been adopted to analyze the calcinated ceramisite under different mixing ratio and environmental conditions. Besides, relevant research methods have been integrated to make a contrast with the calcinated haydie under other mixing ratio and environmental conditions. Later, a quantitative analysis has been conducted to the cylinder pressure strength, water absorption rate and surface density of calcinated ceramisite by integrating qualitative research to obtain the best raw materials proportion and calcination environmental conditions. Finally, comparative analytical method has been adopted to make a quantitative comparison to the economic benefits in ceramisite production with different production techniques and raw materials.We can mainly come to the following conclusion through research in this dissertation:1. It is able to calcinate ceramisite by mixing electroplating sludge and active sludge into the coal fly ash. There are numerous raw materials for ceramisite calcination. And the decisive factor lies in the content ratio of silicon dioxide and aluminium oxide in the raw material. Once the content of above two substances has reached above 80%, the initial conditions for ceramisite calcination have been prepared. Research has shown that the content of above two substances in normal coal fly ash is higher than this ratio. The electroplating sludge and active sludge contain these two substances. At the same time, they contain other metal ions. After a certain ratio of electroplating sludge and active sludge has been added into the coal fly ash, the ceramisite calcination content of silicon dioxide and aluminium oxide can be maintained and heavy metal ion can play a catalytic role——it can not only enhance the ceramisite strength, but also accelerate the calcination speed. The later tests have proven the theoretical judgement.2. Different raw materials mixing ratio will have a rather great influence on the strength of ceramisite calcination. During the test, three groups (X, Y, Z) of samples in different raw materials mixing ratio have been prepard in order to test the influential degree of different raw materials mixing ratio on the ceramisite calcination index. Each group contains 4 samples. The coal fly ash adding ratio changes between 55%-85%; the electroplating sludge adding ratio changes between 0%-40%; the active sludge adding ratio changes between 5%-15%. The result has shown that ceramisite has great color difference under calcination in different raw materials mixing ratio; ceramisite strength gap is 15.5 times. The mixing ratio leading to maximum ceramisite strength is as follows: electroplating sludge: coal fly ash: active sludge= 10:80:5.3. The orthogonal test shall be conducted to find out the optimal environmental conditions for ceramisite calcination. Test has proven that apart from great influence of raw materials ingredient on ceramisite strength, different pre-heat temperature and time and calcination temperature and time will also have rather great influence on ceramisite calcination. The orthogonal test shall be introduced for sieving process in order to find out the optimal calcination conditions. No. 10 sample in the orthogonal test has the greatest ceramisite strength. The cylinder pressure strength is 4.526MPa. And high quality product standard has been reached; the water content rate is 27.3%. Once the index of four elements has reached 700℃pre-heat temperature, 15min pre-heat time, 1200℃calcination temperature and 30min calcination time, ceramisite with maximum cylinder pressure strength can be calcinated.4. After Guangxi white mud is added into the raw material, the ceramisite has obvious change index and cylinder pressure strength is greatly enhanced. The objective of adding Guangxi white mud is to observe ceramisite index changes and compare with electroplating sludge ceramisite without Guangxi white mud. Efforts shall be made to enrich the prescription and choice of electroplating sludge ceramisite calcination. The test is divided into two groups and each group has 32 tests. The additing ratio of Guangxi white mud shall remain 20%. The adding ratio of electroplating sludge has a change margin of 20%-35%, active sludge is 10%-15% and coal fly ash is 30%-50%. The result has shown that the water absorption rate gap of ceramisite is as high as 6993.5 times; the surface density changes between 745.5 kg/m~3-1671.7 kg/m~3. Compared with electroplating sludge ceramisite without Guangxi white mud, the cylinder pressure strength of ceramisite has been generally enhanced. 10.35Mpa ceramisite level has been obtained in the samples. The optimal prescription ratio and calcination environmental conditions in adding Guangxi white mud are as follows: electroplating sludge content: 30%; coal fly ash content: 40%; active sludge content: 10%; Guangxi white mud content: 20%; pre-heat temperature: 600℃; pre-heat time: 15 minutes; calcination temperature: 1175℃; calcination time: 25 minutes.5. The production technique in electroplating sludge ceramisite fabrication shall be selected and economic benefit analysis shall be conducted. The sintering techniques shall be selected for the sinterer through comparison. The net profit in 1m~3 product production is as follows: 20.5 Yuan for coal fly ash ceramisite, 160.125 Yuan for electroplating sludge ceramisite and 503.125 Yuan for electroplating sludge ceramisite added with Guangxi white mud. It means that electroplating sludge ceramisite calcination enjoys obvious economic benefits.Research has shown that there is a broad prospect for electroplating sludge ceramisite production.更多还原