Anaerobic technologies should be considered for domestic wastewater treatment as an alternative to more conventional aerobic technologies in most developing countries for a variety of reasons. Anaerobic technologies already have been applied successfully for the treatment of a number of waste streams, including low strength wastewaters such as domestic wastewater, particularly under tropical conditions. Anaerobic treatment can be carried out with technically simple setups, at any scale, and at almost any place. It produces a small amount of excess, well stabilized sludge, and energy can be recovered in the form of biogas. The process can be carried out in both centralized and decentralized modes, and the latter application can lead to significant savings in investment costs of sewerage systems.
Biotreatment processes of the activated sludge type are the most widely used secondary biotreatment processes for both municipal sewage and industrial wastewater. Activated sludge technology was originally developed some 70 years ago by Ardern and Lockett and today many variants of the process are in use. Essentially, the process involves two main steps: bio-oxidation of biodegradable pollutants in an aeration tank and settling of the biomass and other solids (sludge) in clarifier from whence concentrated sludge is recycled to the aeration tank in order to enhance by dispersed microbial flocs with relatively food settling properties and which can, in many respects, be regarded as pellets of naturally immobilized microbial cells. In general, processes are operated in the continuous flow mode and any excess sludge produced is wasted either continuously or intermittently.
两段文章。谢谢！！
參考答案:由于种种原因,在大多数发展中国家的家庭废水处理问题上,厌氧技术和常用的有氧技术一样,应该做为一种处理方法.厌氧技术在处理一些废水流的方面已得到了成功的应用,其中包括流速不是很急的家庭废水,特别是在热带地区.厌氧处理的技术步骤很简单,可以在任何范围,大多数地方实行.这种技术在应用过程中能产生出少量过剩的,比较稳定的淤泥,能量则以沼气的形式贮存.整个过程可以集中或分散进行.分散进行的话,可以为污水处理工程节省大量的资金.加菌淤泥处理法做为生物处理方法的一种在城市污水和工业污水的二级生物处理上得到广泛的应用.加菌淤泥处理法是由Ardern和Lockett于70年前发明的,如今这种方法衍生出来的其它多种方法得到了应用.本质上,这种方法包括两个主要步骤:将生物所能分解的污染物质放在一个充气槽罐里进行氧化处理,在澄清器内将生物和淤泥沉降下来,沉降下来的物质又被回收到充气槽罐内,目的是为了通过相关的食物沉降性能增加分散微生物的絮凝物,这些絮凝物在许多方面被认做是自然沉降微生物细胞的颗粒状物. 一般而言,整个过程操作起来是连续的,过程中产生的任何淤泥不断或间歇性地被排泄.
