环境工程专业英语翻译14

14.What is physical-chemical treatment（什么是物理化学处理） Some conjecture exists as to a precise definition for physical-chemical treatment(有人推测物理化学处理以一个确切的定义存在)Although other systems might be considered,the only one discussed here is chemical clarification followed bydissolved organic removal.( 虽然其他系统可能会考虑，在这里讨论的只有一个是化学澄清，然后溶解有机物的去除。)The first stage of treatment is designed to provide efficient suspended and colloidal solid removal along with phosphorus removal; the second operation removes a large percentage of the dissolved organic matter.( 第一阶段的处理目的是为市民提供暂性的高效率和胶体的固体去除附着的磷;第二阶段是消除了大比例的溶解有机质)A typical flow diagram of this basic system is shown in figure14-1.（这一基本的一个典型图现在figure14 - 1 。） A number of variations exist for these two operations. In the clarification step there are two primary considerations:the choice of chemicals to be used and the choice of physical equipment.(这两个操作存在一些变异。在澄清这一步，有两个主要因素：选择使用的化学物和选择物理设备。) Essentially,the chemical options are limited to alum,lime or iron salts with or without polymer addition.（基本上，化学选择是有限的，以明矾，石灰或铁盐或无聚合物除。）In the choice of physical equipment ,conventional mixing,flocculation and solids separation must be evaluated versus solids-contact systems. The solids separation process in the conventional sequence can consist of conventional sedimentation,flotation or high rate sedimentation. In addition,a filtration step may be included for improved solids removal.( 在选择常规混合，絮凝和固体分离的实物设备，必须进行评估与固体接触式系统。固体分离的过程中，传统的序列可以是非常规沉淀，气浮或高利率沉淀。此外，在过滤步骤，可包括为改进固体去除。) In the dissolved organic removal step the choiced are generally limited to either granular or powdered activated carbon adsorption. However,other processes such as ozonation have also been proposed for this purpose.the choice of a granular activated carbon(GAC)design requires decisions concerning series or paralled contacting,pressure or gravity vessels and upflow or downflow operaton. Powdered activated caron(PAC)designs primarilly involve the choices between single-stage and two-stage countercurrent contacting.( 在溶解有机物的去除步骤，有选择一般仅限于要么颗粒状或粉末活性炭吸附。然而，其他一些程序，如臭氧，也有人建议，为这个目的，选择一种粒状活性炭（ GAC ）的需要决定串联或并联接触，压力或重力船只和上流式或下行行动中。粉状活性卡伦（委员会）设计，主要涉及选择单阶段和两阶段逆流接触) In addition to these basic operations,provisions can be included for nitrogen removal by ammonia stripping,ion exchange or breakpoint chlorination.（除了这些基本操作规定，可以纳入为脱氮氨吹脱，离子交换或断点加氯。）Other unit processed may also be added to the basic system in order to provide for the specific requirments of any application.(其他单位处理，也可添加到基本制度，为了提供具体所需的任何申请。) For example,desinfection or final filtration steps may be desirable in many locations. (举例来说，消毒或过滤的最后步骤，在许多地点可能是可取的。)Of course,the treatment and disposal of the sludge from the clarification step,the regeneration of spent actvated carbon and management of backwash streams represent some of the additional design considerations. (当然，，从澄清一步处理及处置污泥，再生废活性炭和管理的反冲溪流代表的部分额外的设计考虑。)