Operations used for the treatment of wastewater in which change is brought about by means of or through the application of physical forces are known as physical unit operations. Because physical unit operations were derived originally from observations of the physical world, they were the first treatment methods to be used. Today, physical unit operations, as shown on Fig. 5-1, are a major part of most wastewater

The activated-sludge process is now used routinely for biological treatment of municipal and industrial wastewaters. The antecedents of the activated-sludge process date back to the early 1880s to the work of Dr. Angus Smith, who investigated the aeration of wastewater in tanks and the hastening of the oxidation of the organic matter

1、 我国的水环境污染与治理情况 2、 我国污水的综合排放标准 3、 污水处理方法的分类 4、 活性污泥法在污水处理中的重要作用 5、 典型的城市污水处理工艺流程 6 、 活性污泥法的发展方向

薄膜的聚集密度： P=薄膜中固体部分的体积：薄膜的总体积 薄膜的P在0.75～0.95之间，而大块材料P为1 牢固度和硬度、耐潮湿本领 下降、光的散射和吸收损失 加大导致耐激光损伤能力下 降，折射率随外界环境发生 变化

The first three types of control devices we consider--gravity settlers, cyclone separators, and electrostatic precipitators--all function by driving the particles to a solid wall, where they adhere to each other to form agglomerates that can be removed from the collection device and disposed of

Attached growth processes can be grouped into three general classes: (1) nonsubmerged attached growth processes, (2) suspended growth processes with fixed-film packing, and (3) submerged attached growth aerobic processes. Nonsubmerged Attached Growth Processes. Trickling filters with rock packing have been a common

噪声和振动有着非常密切的关系。许多噪声是由振动引起的，这种振动以弹性波的形式在空气、液体和固体介质中进行传播，分别称为气体声、液体声和固体声，通常将固体声称为振动。噪声和振动污染的控制原理十分相似：隔振的同时也起到降噪作用

一、 大气污染的基本概念 早在英国爱德华二世(1284～1327)年代，这位国王就曾想通过禁止使用煤来解决燃 煤产生的烟气污染问题。他曾颁布了一道法令：“无论是谁被发现燃烧煤，他就是有罪 的，都将受到杀头的惩罚”。由此可见，大气污染自古有之

The safe and reliable long-term disposal of solid waste residues is an important component of integrated waste management. Solid waste residues are waste components that are not recycled, that remain after processing at a materials recovery facility, or that remain after the recovery of conversion products and/or energy. Historically, solid waste has been placed in the soil in the earth's surface or deposited in the oceans

Solid wastes comprise all the wastes arising from human and animal activities that are normally solid and that are discarded as useless or unwanted. The term solid waste as used in this text is all-inclusive, encompassing the heterogeneous mass of throwaways from the urban community as well as the more homogeneous accumulation of agricultural, industrial