Worldwide there is an increasing industrialization leads to increased disposal of uncontrolled waste products into the environment which made the environment more pollute and creates hazards. Industrial wastewater is having a major role in the environmental pollution. The major physical, chemical and biological products of the wastewater are solid content, organic matter, in-organic compounds, detergents, soap, cleaning products, metals, gases, volatile compounds, numerous pathogenic microorganisms, nutrients and toxic compounds. Untreated wastewater can cause various environment pollutions problems such as eutrophication or oxygen depletion in the environment. Hence a effective wastewater treatment process and its management is necessary to reduce the contaminants in the permissible levels in the treated waste streams. The final outcome of an effective wastewater treatment and its management is to ensure and provide an appropriate environment protection to the living things and public human beings in the world.
TopIntroduction
Wastewater is a combination of water and water-carried wastes originating from homes, commercial, industrial facilities and from various institutions. Untreated wastewater generally contains more than 99% of water, but the remainder contains high levels of organic material, small amounts of inorganic ions, numerous pathogenic microorganisms, nutrients and toxic compounds leads to environmental pollution and health hazards.
Wastewater treatment is becomes a critical one due to its water resources, disposal costs, regulations which reduces the wastewater contaminant levels in the disposal waste water streams. The critical goal of waste water treatment and its management is to protect the environment, public health and at last the socio-economic concerns (Tchobanoglous & Burton 1991).
Hence, waste water must be treated suitably to meet the required standard before it is getting disposed to protect the environment from the pollution and prevent the health hazards of the human beings.
Choosing an appropriate waste water treatment technology is depends upon the nature of the contents in the waste water.
Selecting a suitable waste water treatment process is depends upon:
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How clean the final water effluent from our plant must be.
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The quantities and nature of the influent water we need to treat.
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The physical and chemical properties of the pollutants we need to remove or render to neutral in the effluent water.
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The physical, chemical and thermodynamic properties of the solid wastes generated from treating water. (Cheremisinff, 2002)
Treatment of Wastewater
Generally wastewater treatment is carried out in four stages. They are:
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Preliminary treatment
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Primary treatment
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Secondary treatment
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Tertiary treatment (Bozkurt et al., 2015; Kalbar et al., 2012; Garrido et al., 2011; Al-Rekabi et al., 2007)
Various Treatment Procedures
Preliminary Treatment
Solids and oil with grease are combined to form sludge. Preliminary treatment is the first process which makes the effluent suitable for further process by reducing the non-favourable wastewater characteristics like large solids and rags, abrasive grit, odours and in certain cases, unacceptably high peak hydraulic or organic loadings.
Preliminary treatment processes consist of screening/filtration as physical unit operation which removes the coarse suspended matter and flotation for the removal of oil and grease. Other preliminary treatment operations are comminution, removal of greases and oils, flow equalization, equalization and neutralization of acid wastes and alkaline wastes.