污泥活性炭的制备及其在污水处理中的应用研究现状

市政污水处理厂在处理污水的同时会产生大量污泥,如果处理不当,将会造成严重的环境污染和资源浪费。污泥制备吸附剂因能使其稳定化而展现出特殊前景。利用市政污泥制备活性炭,不仅可以实现污泥的资源化利用,而且可以生产用途广泛的廉价吸附材料,具有良好的环境效益和社会效益,引起国内外研究者的高度关注和深入研究。综述了国内外污泥活性炭的制备研究进展及其在污水处理中的应用研究现状,综合分析了污泥活性炭对废水中污染物的吸附效果。     

污泥基活性炭的制备及其在环境污染治理中的应用进展

从污泥基活性炭的制备及其在水和大气环境领域的应用两个部分进行了综述。主要总结了3种传统制备方法的原理;同时,对比了7种不同制备方法的优缺点和主要用途,汇总了通过添加农作物秸秆和矿物来提升污泥活性炭性质的相关研究。污泥基活性炭在环境领域的应用主要包括其对废水中有机染料、有机药物、小分子有机化合物和重金属的吸附以及其对硫化氢等工业废气和甲醛等室内废气的净化。另外,分别举例说明了不同来源污泥基活性炭的用途和性能。最后,总结分析了污泥基活性炭在研究中存在的问题以及今后的主要发展方向。     

污水厂剩余污泥材料化和能源利用技术研究进展

剩余污泥为污水处理厂副产物,具有成分复杂难处理,易滋生二次污染的特性。主要介绍了近年来剩余污泥制吸附剂和能源化技术的研究进展。由于剩余污泥中有机质含量丰富,首先对单一污泥和剩余污泥添加工农业废弃物制备吸附剂的研究现状进行了介绍,指出吸附材料制备过程中活化剂大量使用会造成环境的再污染;随后综述了剩余污泥直接能源化,或通过热解等手段将其间接能源化的研究进展;最后提出用生物质废弃物代替化学活化剂制备污泥吸附剂的研究思路,并指出将污泥制备材料和能源利用技术相结合是今后剩余污泥资源化研究的主要发展方向。     

污泥填料制备实验研究

本文是以脱水污泥为骨料制备用于污水处理中生物膜载体填料,探索了以废制废、污泥资源化的新途径.实验使用脱水污泥为主要原料、粉煤灰和牯土为添加剂,得到制备填科最佳成分配比和最佳工艺条件是烧成温度为1000±25℃、污泥掺量为70%、保温时间为40min,填料的抗压强度达到25Mpa、吸水率17%,污泥填料处理药厂废水常温下CODCr的平均去除率为74.091、SS去除率为54.1%.结果表明,污泥作骨科,可以制备出性能优良的填料.     

污泥基生物炭的制备及其对萘的吸附性能研究

为了探索市政生活污水处理厂剩余活性污泥资源化方式，以市政污泥为原料，采用热解法制备污泥基生物炭(SBC),探究SBC最佳制备条件以及对多环芳烃萘的吸附影响因素。结果表明：SBC的最佳制备条件为污泥粒径0.25mm,升温速率2.5℃/min,热解温度800℃,停留时间1h,在该条件下市政污泥的产炭率、产油率和产气率分别为61.36%、15.55%和23.09%;SBC对萘的最佳吸附条件为转速200r/min,温度35℃,投加量0.4g,在该条件下萘的去除率可达85.06%;SBC对萘的吸附过程符合准二级动力学模型，Langmuir等温吸附模型可以更好地描述SBC对萘的吸附。扫描电子显微镜和BET比表面积分析表明，SBC表面粗糙，具有丰富的孔隙结构，能有效吸附废水中的萘。     

污泥制备活性炭对 Pb(Ⅱ)和Ni(Ⅱ)的吸附和回收利用

在静态条件下研究了用污泥制备的活性炭吸附剂去除水溶液中Pb(Ⅱ)、Ni(Ⅱ)的效果,考察了溶液pH值、吸附时间、吸附剂用量和Pb(Ⅱ)、Ni(Ⅱ)的初始浓度对去除率的影响.结果表明,污泥制备的活性炭吸附剂对Pb(Ⅱ)、Ni(Ⅱ)具有较强的吸附性能,pH值是影响吸附的主要因素;吸附过程符合Langmuir吸附等温式;在试验条件下,其对Pb(Ⅱ)具有更高的去除能力.还探讨了吸附Pb(Ⅱ)、Ni(Ⅱ)后回收铅和镍的可行性.     

Fenton试剂预活化污泥制备活性炭及对腐殖酸吸附作用

采用Fenton试剂对污泥进行预处理,将制成的污泥基活性炭(SBAC)作为环保材料应用于吸附治理环境水体中腐殖酸,研究了吸附过程中的理论问题。实验结果表明,Fenton试剂对污泥进行预处理可有效改善吸附材料的化学活性并提高污泥基活性炭(SBAC)的孔隙率(比表面积由原来的92.65m2/g增加至172.8m2/g),增大了材料的吸附容量;近中性水液中吸附容量较大,升高温度有利于吸附;298K,pH值=8时,污泥基活性炭对腐殖酸的最大吸附容量为89.63mg/g,大于市售颗粒活性炭和凹凸棒/活性炭;吸附过程符合Freundlich等温模型,对吸附动力学的拟合结果表明,该过程更符合Lagergren二级动力学方程;吸附过程吸热、熵值增加,常温下可自发进行。污泥基活性炭可用于吸附去除水体中腐殖酸。     

丽水市污水处理设施污泥的年产生量及处置方法调查分析

通过对丽水市下属九县市区污水处理设施的全面调查,分析近年来污水处理设施污泥的年产生量及处置方法,建议深化污泥的无害化处置工作,加强污泥无害化处置设施建设,阐述对污泥这一固废处理的必要性和紧迫性。     

泥质活性炭对三种染料的吸附性能

利用污水处理厂污泥为原料制备了泥质活性炭,通过静态吸附实验探究了泥质活性炭对三种染料(酸性大红GR、碱性湖蓝BB和活性艳兰B-RV)去除率的影响因素,从动力学角度探讨其吸附机理。结果表明,泥质活性炭投加量、吸附时间、染料初始浓度、pH值对染料去除率有显著影响,吸附温度对染料去除率无明显影响。泥质活性炭对三种染料平衡吸附量(qe)均随着初始浓度增加而增加,相同条件下,平衡吸附量(qe)大小顺序为碱性湖蓝BB酸性大红GR活性艳兰B-RV。采用伪二级动力学模型能够很好地描述三种染料在泥质活性炭上的吸附动力学行为,伪二级动力学模型包含了外部液膜扩散、表面吸附和颗粒内扩散等在内的所有吸附过程。     

燃煤电厂脱硫废水及污泥中重金属污染物控制研究进展

燃煤发电中常采用湿法烟气脱硫技术,该工艺会产生含有重金属污染物的脱硫废水和污泥,潜在环境危害性强,需谨慎处理。介绍了燃煤电厂脱硫废水和脱硫污泥的产生来源、成分组成、重金属污染物含量水平和排放处置标准,对沉淀法等脱硫废水重金属处理技术和脱硫污泥重金属去除及固化技术的原理、优点、适用性和局限性进行总结对比分析。脱硫废水重金属控制方法中,目前普遍使用的三联箱工艺难以满足日益严格的排放标准,需进行改进;吸附法、微生物法等新型方法也因成本和技术等问题而难以普及;零排放技术因其无污染的特性将逐渐成为研究和推广的主流。脱硫污泥重金属控制方法大多仍处于研究中,化学修复和药剂固化方法因效果好、适用性强将逐渐在电厂生产实践中推广。     

Treatment of sewage sludge using electrokinetic geosynthetics

The treatment and disposal of sewage sludge is one of the most problematical issues affecting wastewater treatment in the developed world. The traditional outlets for sewage sludge are to spread it on agricultural land, or to form a cake for deposit to landfill or incineration. In order to create a sludge cake, water must be removed. Existing dewatering technology based on pressure can only remove a very limited amount of this water because of the way in which water is bound to the sludge particles or flocs. Several researchers have shown that electrokinetic dewatering of sludge is more efficient than conventional hydraulically driven methods. This involves the application of a dc voltage across the sludge, driving water under an electrical gradient from positive (anode) electrode to negative (cathode) electrode. However, there have been several reasons why this technique has not been adopted in practice, not least because the, normally metallic, anode rapidly dissolves due to the acidic environment created by the electrolysis of water. This paper will describe experimentation using electrokinetic geosynthetics (EKG): polymer-based materials containing conducting elements. These have been used to minimise the problem of electrode corrosion and create a sludge treatment system that can produce dry solids contents in excess of 30%. It will suggest different options for the treatment of sludges both in situ in sludge lagoons and windrows, and ex situ as a treatment process.     

污泥-高钙煤系废物制备地聚合物的技术与性能

鉴于地聚合物是一种低碳排放且能源、资源消耗较少的新型胶凝材料,其制备技术倍受关注。采用热活化污泥和高钙煤系废物制备地聚合物,并与采用高钙粉煤灰和矸石制备地聚合物的反应机制与性能进行了对比分析,确定了制备污泥-高钙煤系废物地聚合物的最佳工艺参数。采用XRD、SEM、TG-DTA及FTIR等对制备的地聚合物的原料组成和性能进行了深入分析。研究表明: 经900℃焙烧45 min掺量为40%(＜50 μm)热活化污泥-煤系废物制备的地聚合物具有较好的抗压强度。无定形地聚合物胶凝包裹在球状粉煤灰颗粒周围,有类沸石矿物生成,Al—O/Si—O对称伸缩峰及Si—O—Si/Si—O—Al弯曲振动峰明显。     

Preparation of adsorbents made from sewage sludges for adsorption of organic materials from wastewater

The carbon-bearing adsorbents were prepared from biochemical and surplus sludges by physical activation and chemical activation. The results indicated that the adsorbents made by way of chemical activation were better, with the optimum activator being complex of ZnCl(2) and H(2)SO(4). Moreover, the optimum preparation conditions were concentration of two activators 5 mol/L (the ratio of ZnCl(2) and H(2)SO(4) was 2:1), at the activating temperature of 550 degrees C, in the proportion of solid to liquid 1:2.5, in a period of 2h. Contrasting the active carbon, the carbon-bearing adsorbents were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM), BET and BJH. By application of those adsorbents to treatment of wastewater of urban, the treatment effect of the carbon-bearing adsorbents were better than the active carbon. On the condition that the concentration was 0.5%, the COD, P and chromaticity color removal rates of carbon-bearing adsorbent made from the biochemical sludge of sewage were higher, which were 79.1, 98.3 and 87.5%, respectively, and the dynamic adsorption capacity was 47.8 mg/g.     

Carbon‐Based Functional Materials Derived from Waste for Water Remediation and Energy Storage

Carbon‐based functional materials hold the key for solving global challenges in the areas of water scarcity and the energy crisis. Although carbon nanotubes (CNTs) and graphene have shown promising results in various fields of application, their high preparation cost and low production yield still dramatically hinder their wide practical applications. Therefore, there is an urgent call for preparing carbon‐based functional materials from low‐cost, abundant, and sustainable sources. Recent innovative strategies have been developed to convert various waste materials into valuable carbon‐based functional materials. These waste‐derived carbon‐based functional materials have shown great potential in many applications, especially as sorbents for water remediation and electrodes for energy storage. Here, the research progress in the preparation of waste‐derived carbon‐based functional materials is summarized, along with their applications in water remediation and energy storage; challenges and future research directions in this emerging research field are also discussed.     

转炉污泥吸附性能研究

Converter sludge, a byproduct produced on large amounts in the steel making process, is an important resource that can be utilized effectively. This paper describes an experiment in which converter sludge was tested as an adsorbent for the removal of phosphorus from waste water. It was found that the phosphorus removal depended on the amount of converter sludge added, the pH value and the contact time. Under laboratory conditions when the added sludge was 2. 0mg/100ml, the contact time 4h and the pH value of equalized 4, over 88% of phosphorus was removed; the experimental data on converter sludge adsorption of phosphorus in the water fitted the Freundlich isotherm model. Converter sludge was found to be very effective in adsorbing the phosphorus.     

Review of technologies for oil and gas produced water treatment

Produced water is the largest waste stream generated in oil and gas industries. It is a mixture of different organic and inorganic compounds. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging produced water on the environment has lately become a significant issue of environmental concern. Produced water is conventionally treated through different physical, chemical, and biological methods. In offshore platforms because of space constraints, compact physical and chemical systems are used. However, current technologies cannot remove small-suspended oil particles and dissolved elements. Besides, many chemical treatments, whose initial and/or running cost are high and produce hazardous sludge. In onshore facilities, biological pretreatment of oily wastewater can be a cost-effective and environmental friendly method. As high salt concentration and variations of influent characteristics have direct influence on the turbidity of the effluent, it is appropriate to incorporate a physical treatment, e.g., membrane to refine the final effluent. For these reasons, major research efforts in the future could focus on the optimization of current technologies and use of combined physico-chemical and/or biological treatment of produced water in order to comply with reuse and discharge limits.     

Environmental-benign utilisation of fly ash as low-cost adsorbents

Fly ash is a waste substance from thermal power plants, steel mills, etc. that is found in abundance in the world. In recent years, utilisation of fly ash has gained much attention in public and industry, which will help reduce the environmental burden and enhance economic benefit. In this paper, the technical feasibility of utilisation of fly ash as a low-cost adsorbent for various adsorption processes for removal of pollutants in air and water systems has been reviewed. Instead of using commercial activated carbon or zeolites, a lot of researches have been conducted using fly ash for adsorption of NO(x), SO(x), organic compounds, and mercury in air, and cations, anions, dyes and other organic matters in waters. It is recognised that fly ash is a promising adsorbent for removal of various pollutants. Chemical treatment of fly ash will make conversion of fly ash into a more efficient adsorbent for gas and water cleaning. Investigations also revealed that unburned carbon component in fly ash plays an important role in adsorption capacity. Directions for future research are also discussed.