Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater, both runoff and
domestic. It includes physical, chemical and biological processes to remove physical, chemical and biological contaminants. Its
objective is to produce a wastestream (or treated effluent) and a solid waste or sludge also suitable for discharge or reuse back into
the environment. This material is often inadvertently contaminated with toxic organic and inorganic compounds.
Sewage is created by residences, institutions, and commercial and industrial establishments. It can be treated close to where it is
created (in septic tanks or onsite package plants and other aerobic treatment systems), or collected and transported via a network of
pipes and pump stations to a municipal treatment plant. Sewage collection and treatment is typically subject to local, state and
federal regulations and standards. Industrial sources of wastewater often require specialized treatment processes.
Typically, sewage treatment involves three stages, called primary, secondary and tertiary treatment. First, the solids are separated
from the wastewater stream. Then dissolved biological matter is progressively converted into a solid mass by using indigenous,
water-borne bacteria. Finally, the biological solids are neutralized then disposed of or re-used, and the treated water may be
disinfected chemically or physically (for example by chlorination, UV and/or micro-filtration). The final effluent can be discharged
into a stream, river, bay, lagoon or wetland, or it can be used for the irrigation of a golf course, greenway or park. If it is sufficiently
clean, it can also be used for groundwater recharge.
There are some picture taken after the project done by OCNED Water Technology Sdn Bhd.

Overview of STP at Proton City Development Corporation Sdn Bhd at Tanjong Malim
Perak Darul Ridzuan

Surface Aerator in operation (Oxidation Ditch Process)
Clarifier (Sedimentation tank)

