有机废物厌氧消化工艺应用现状及前景展望

与其他常规处理方法相比，利用厌氧消化技术处理有机废物更具有优嚏，因为它不仅可以有效减少污省染，还可以产生很好的经济效益和巨大的环境效益。简要介绍了厌氧消化技术的机理、影响因素、类型，以及在有机废物处理领域的应用现状，并重点介绍了国外近年来发展形成的典型厌氧消化工艺，同时分析了厌氧消化技术在有机废物资源化处理领域的广阔应用前景。     

柠檬酸生产废水处理技术

分析了柠檬酸生产废水的来源及水质特性,综述了厌氧生物法、厌氧-好氧生物组合法、乳状液膜法等在柠檬酸废水处理中的应用,介绍了中和废水回用和利用柠檬酸发酵废液开发糖化酶制剂的技术。     

有机固体废物高效腐殖化微生物调控原理与技术

堆肥作为有机固体废物资源化处理处置的方式之一,腐殖化效率低是制约其发展的瓶颈.本文从生物强化调控、微环境调控和调理剂调控3方面,系统梳理了有机固体废物腐殖化微生物调控原理和调控技术,并从基础理论层面和技术研发层面对该领域今后的研究方向进行了展望.指出:生物强化调控技术在腐殖化研究中前景较好;应重点关注腐殖化和矿化过程中...     

电化学法处理被污染土壤或水

美国LawrenceBerkeley国家实验室开发了一种新型的污染物生物处理系统，可用于处理被污染的土壤和水。常规的生物电处理方法是依靠化学药物的加入产生电子供体或受体，以刺激降解微生物的代谢过程。而该实验室的方法则是在一个单室的生物反应器中，采用电流电解被污染的液体，同时在阴极产生氢气、在阳极产生氧气。这些气体随后可刺激微生物的活性，使多种污染物经生物降解或生物转化作用形成良性的终端产品。由于不需有机电子供体，降低了操作成本。     

有机废水处理装置

该发明提供了一套处理有机废水的装置，依次为厌氧生物反应器、好氧生物反应器、膜分离反应器。该装置能通过生物处理过程去除水中的有机污染物，并用膜将固体与液体彻底分离。用该装置处理有机废水，可有效去除有机污染物、避免膜表面的结垢和剥落等问题，并可降低成本、提高效率。     

油气开采钻井固体废物处理与利用研究现状

对比分析了我国部分地区油气开采钻井固体废物的污染特征,对普通钻井固体废物和含油钻井固体废物的无害化处理与资源化利用技术分别进行梳理和分析,主要包括固化处理技术、生物处理技术、不落地处理技术、资源化利用技术、萃取技术、热解析技术和组合处理技术等。结合当前存在的主要问题针对性地提出了4条对策建议:加强源头控制,减少钻井固体废物产生量;对钻井固体废物进行分质分级区别处理和利用;开发高效、低成本、低能耗的钻井固体废物处理技术,发展联合处理工艺;制定相关政策和标准,加强油气田污染治理的事中事后监管。     

复合生物曝气工艺处理化纤生产废水

仪征化纤股份有限公司所排生产废水中以乙二醇和对苯二甲酸等有机物为主,有机负荷变化较大。复合生物曝气工艺是将传统的活性污泥法与生物膜法有机结合的高效废水处理工艺。即在普通活性污泥工艺的曝气池中投加各种能提供微生物附着生长表面的载体,利用载体容易截留和附着生物量大的特点,使曝气池中同时存在附着相和悬浮相生物,充分发挥两者的优越性,使之扬长避短,相互补充。由于该工艺兼有活性污泥和生物膜法的工艺特点,反应系统中厌氧和兼性厌氧菌的比例较高,生物膜中丝状微生物的数量和种类较多,且食物链稳定。     

好氧—厌氧微生物反复耦合处理废水新工艺

该发明公开了一种好氧—厌氧微生物反复耦合处理废水新工艺。采用生物流化床和生物固定床串联的工艺，先在流化床和固定床之间用溢流隔板连接组合起来；后在流化床和固定床中添加两种不同的多孔生物载体，通过在不同层次上的好氧—厌氧反复耦合，从而在实现处理废水中有机物和氮化合物的同时，原位分解剩余污泥。     

信息与动态

利用废物制氢的方法ChemicalEngineering,2005,112(8):17,18日本静冈大学的研究人员发明了从造纸黑液市政垃圾、碎纸甚至猪粪等生物质中一步法生产氢气的方法。该过程在超临界水(SCW)中完成,可产生比常规的重整—气化工艺多2～5倍的氢气。用废塑料制氢时,通常采用两步工艺:首先在0.5～2MPa压力下生成蒸汽,然后在1300～140℃、0.5～2MPa压力下进行气化—氧化。这一工艺的氢气收率仅为每克废物(以有机碳计)中不到1L。而采用SCW工艺时,生物质于700℃、10MPa压力下在高压反应器中气化和反应。当总进料中的水与碳的摩尔比为20、并加入质量…     

废水厌氧处理系统微量金属生物有效度及影响因素

介绍了废水厌氧处理系统中微量金属营养元素生物有效度的概念,分析了影响微量金属营养元素生物有效度的诸多因素。厌氧生物处理系统存在微量金属营养元素并不等于存在微量金属营养元素生物有效度;对厌氧生物处理系统进行微量金属营养元素生物有效度的检定是非常必要的;微生物的螯合作用对微量金属营养元素生物有效度起非常重要的作用;微量金属营养元素必须直接加入反应器内才能充分保证其生物有效度。     

Comparison of aerobic and anaerobic stability indices through a MSW biological treatment process

A complex mechanical-biological waste treatment plant designed for the processing of mixed municipal solid wastes (MSW) and source-selected organic fraction of municipal solid wastes (OFMSW) has been studied by using stability indices related to aerobic (respiration index, RI) and anaerobic conditions (biochemical methane potential, BMP). Several selected stages of the plant have been characterized: waste inputs, mechanically treated wastes, anaerobically digested materials and composted wastes, according to the treatment sequence used in the plant. Results obtained showed that the main stages responsible for waste stabilization were the two first stages: mechanical separation and anaerobic digestion with a diminution of both RI and BMP around 40% and 60%, respectively, whereas the third stage, composting of digested materials, produced lesser biological degradation (20-30%). The results related to waste stabilization were similar in both lines (MSW and OFMSW), although the indices obtained for MSW were significantly lower than those obtained for OFMSW, which demonstrated a high biodegradability of OFMSW. The methodology proposed can be used for the characterization of organic wastes and the determination of the efficiency of operation units used in mechanical-biological waste treatment plants.     

An overview on olive mill wastes and their valorisation methods

Olive mill wastes represent an important environmental problem in Mediterranean areas where they are generated in huge quantities in short periods of time. Their high phenol, lipid and organic acid concentrations turn them into phytotoxic materials, but these wastes also contain valuable resources such as a large proportion of organic matter and a wide range of nutrients that could be recycled. In this article, recent research studies for the valorisation of olive mill wastes performed by several authors were reviewed: second oil extraction, combustion, gasification, anaerobic digestion, composting and solid fermentation are some of the methods proposed. Special attention was paid to the new solid waste generated during the extraction of olive oil by the two-phase system. The peculiar physicochemical properties of the new solid waste, called two-phase olive mill waste, caused specific management problems in the olive mills that have led to the adaptation and transformation of the traditional valorisation strategies. The selection of the most suitable or appropriate valorisation strategy will depend on the social, agricultural or industrial environment of the olive mill. Although some methods are strongly consolidated in this sector, other options, more respectful with the environment, should also be considered.     

The influence of sodium on biohydrogen production from food waste by anaerobic fermentation

Anaerobic fermentation of food waste for hydrogen production was performed in serum bottles with various linear alkylbenzene sulfonate (LAS) dosages (7.1–21.4 g/l) and sodium concentrations (5.03–28.7 g/l). LAS can effectively inhibit the activity of hydrogen-consuming bacteria, and the maximum hydrogen yield of 109.2 ml/g volatile solid (VS) was obtained at an LAS dosage of 14.3 g/l without added sodium. The feasible pH for hydrogen production is 5.0–6.0, and the process will slow down or stop when the pH is below 5.0.The hydrogen production potential increased when the sodium concentration increased in the range 5.03–14.41 g/l. The maximum hydrogen yield was 154.8 ml/g VS, and then the hydrogen production began to decrease when the sodium concentration increased further. A sodium chloride concentration of 20 g/l and higher will enhance the osmotic pressure and make bacteria inert. In the effluent, acetic acid is the major by-product. The results indicated that the hydrogen production from the anaerobic fermentation of food waste could clearly be increased with the additives and a sodium concentration less than 20 g/l.     

Biodegradability of leathers through anaerobic pathway

Leather processing generates huge amounts of both solid and liquid wastes. The management of solid wastes, especially tanned leather waste, is a challenging problem faced by tanners. Hence, studies on biodegradability of leather become imperative. In this present work, biodegradability of untanned, chrome tanned and vegetable tanned leather under anaerobic conditions has been addressed. Two different sources of anaerobes have been used for this purpose. The effect of detanning as a pretreatment method before subjecting the leather to biodegradation has also been studied. It has been found that vegetable tanned leather leads to more gas production than chrome tanned leather. Mixed anaerobic isolates when employed as an inoculum are able to degrade the soluble organics of vegetable tanned material and thus exhibit an increased level of gas production during the initial days, compared to the results of the treatments that received the anaerobic sludge. With chrome tanned materials, there was not much change in the volume of the gas produced from the two different sources. It has been found that detanning tends to improve the biodegradability of both types of leathers.     

A kinetic analysis of solid waste composting at optimal conditions

This discussion explores the possibility of having a measure of the biodegradable organic carbon content in solid wastes. Currently, indirect measures for determining the concentration of biodegradable organic matter are being used and most of them are based on respiration indices (oxygen consumption or carbon dioxide production) or chemical parameters (volatile solids or total organic carbon). The results obtained for the cumulative carbon dioxide production in composting experiments can be expressed as "aerobic biodegradable carbon" for the wastes that were studied. The calculation of a useful biodegradable C/N can also be obtained from the aerobic biodegradable carbon content. A comparison with some results obtained in measuring the concentration of "anaerobic biodegradable carbon" also is presented.     

Recycling MSWI bottom and fly ash as raw materials for Portland cement

Municipal solid waste incineration (MSWI) ash is rich in heavy metals and salts. The disposal of MSWI ash without proper treatment may cause serious environmental problems. Recently, the local cement industry in Taiwan has played an important role in the management of solid wastes because it can utilize various kinds of wastes as either fuels or raw materials. The objective of this study is to assess the possibility of MSWI ash reuse as a raw material for cement production. The ash was first washed with water and acid to remove the chlorides, which could cause serious corrosion in the cement kiln. Various amounts of pre-washed ash were added to replace the clay component of the raw materials for cement production. The allowable limits of chloride in the fly ash and bottom ash were found to be 1.75% and 3.50% respectively. The results indicate that cement production can be a feasible alternative for MSWI ash management. It is also evident that the addition of either fly ash or bottom ash did not have any effect on the compressive strength of the clinker. Cement products conformed to the Chinese National Standard (CNS) of Type II Portland cement with one exception, the setting time of the clinker was much longer.     

氟化工“三废”的资源化利用

结合我国氟化工行业发展现状,分析了含氟"三废"产生情况及处置方法的最新研究进展,并通过实际工程案例进行论述。氟化工生产过程污染物主要有含氟废气及副产氯化氢、含氟高沸物及含氟污泥等。通过将氯化氢用于工业清洗及制备氯化钙、氯化铝等化学品能够合理消耗副产盐酸。焚烧处理含氟有机废气产生的氟化氢气体经水洗后副产氢氟酸。含氟高沸物通过精馏分离出高沸物组分生产高附加值产品。含氟污泥可制成建筑材料,最优工业化利用途径仍在积极研究中。     

Study of the operational conditions for anaerobic digestion of urban solid wastes

This paper describes an experimental evaluation of anaerobic digestion technology as an option for the management of organic solid waste in developing countries. As raw material, a real and heterogeneous organic waste from urban solid wastes was used. In the first experimental phase, seed selection was achieved through an evaluation of three different anaerobic sludges coming from wastewater treatment plants. The methanization potential of these sludges was assessed in three different batch digesters of 500 mL, at two temperature levels. The results showed that by increasing the temperature to 15 degrees C above room temperature, the methane production increases to three times. So, the best results were obtained in the digester fed with a mixed sludge, working at mesophilic conditions (38-40 degrees C). Then, this selected seed was used at the next experimental phase, testing at different digestion times (DT) of 25, 20 and 18 days in a bigger batch digester of 20 L with a reaction volume of 13 L. The conversion rates were registered at the lowest DT (18 days), reaching 44.9 L/kg(-1) of wet wasteday(-1). Moreover, DT also has a strong influence over COD removal, because there is a direct relationship between solids removal inside the reactor and DT.     

厌氧消化中硫酸盐毒性的控制

探讨了厌氧消化中硫酸盐还原菌与产甲烷菌对分子氢的两种竞争作用及硫酸盐的致毒机制，归纳分析了目前对含硫酸盐有机废水厌氧处理可能采用的几种毒性控制对策及其存在问题。