There are two basic stages in the treat- ment of wastes, primary and secondary, which are outlined here.
In the primary stage, solids are allowed to settle and removed from wastewater.
The secondary stage uses biological processes to further purify wastewater.
Sometimes, these stages are combined into one operation..
Among such key cost factors are the average diameter and average depth of sewers; average slope relative to ground topography; the number and depths of man- holes; and other factors such as total sewer length, population density, set-up costs, and excavation in rock..
Sewage treatment removes contaminants from municipal wastewater, containing mainly household sewage plus some industrial wastewater.
Sewage treatment units are normally designed for 15-20 years and for average flow..
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A basis of design (BOD) for a wastewater treatment facility project documents the principles, assumptions, rationale, criteria, calculations, and decisions made that impact the final design..
It is proposed to design the various components of sewage treatment plant considering the various standards and permissible limits of treated sewage water.
The various components of sewage treatment plant are screening, grit chamber, primary sedimentation tank, biological reactor, secondary clarifier, activated sludge tank and drying beds.
Wastewater treatment takes place in wastewater treatment plants, which should be designed under different circumstances.
The criteria are being considered in this design for wastewater treatment plant (WWTP) Al-Hay.
Moreover, the characteristics of physical, chemical and biological wastewater also are described.
A wastewater treatment facility shall ordinarily be designed to provide for the projected population at least 15 years hence.
Whenever cost-effectiveness permits, the construction may be programmed in stages.
The paper can be beneficial for public area especially in Iraq.
Design wastewater treatment plant can reduce the amount of waste that is usually released into the environment.
By doing so, the reduction in the health risks associated with environment pollution thus improving environment’s health.
