Question

3) Describe the purposes of the principle process involved in treatment of waste water .

Answer 1

Hi Answer:

Describe the purposes of the principle process involved in the treatment of wastewater

Answer: The wastewater is that water which is generated by the use of water means this water has no use we can use this water for drinking and other purposes without cleaning. It’s formed by a number of activities including bathing, washing, using the toilet, and rainwater runoff. This water cannot be returned directly into the environment because it contains a number of bacteria, chemicals, and other toxic substances. The cleaning or purification of this wastewater is necessary before returning back it to nature. The wastewater can be cleaned by two major treatment processes i.e.(i) Physical and Chemical treatment (ii) Biological treatment.

The physical and chemical treatment plants are mainly used to treat wastewater evolved from industries, in this technique use of various chemical processes is carried out to neutralize various harmful substances. Whereas in case of biological wastewater treatment plants household wastewater is treated with the help of various microbial systems. These organisms consume the organic matter present in wastewater for their growth and purify the water.

Various Processes involved in wastewater treatment and their purposes

(i)    Wastewater collection and order control: It is the first step of the treatment in this phase the wastewater of all sources is collected at a particular place or tank and after that the order of wastewater is controlled as wastewater contain lots of dirty things a bad order is generated which is controlled by the use of some chemicals or neutralizing agents. This neutralization step is carried out to keep the environment healthy.

(ii)    Screening: In this step, the wastewater is screened for the presence of various materials such as cotton buds, plastics, diapers, rags, sanitary items, nappies, face wipes, broken bottles or bottle tops etc. This is simply carried out by the filtration of wastewater. This step is very much important and the whole process is depending on this step because if there is no screening then these items may damage the machines used in treatment plants by choking them.

(iii)    Primary treatment: In this step, the micro solids are separated from the wastewater by simply pouring the water in big tanks and allow the solids to settle down. After that, this primary treated wastewater subjected to secondary treatment.

(iv)    Secondary treatment: In this technique is sludge water is added to the wastewater to initiate the treatment. In this step the bacteria which grow in organic waste break down the complex organic matter into simpler one. The formation of sludge takes place in this step.

(v)    Biosolid handling: In this process, solid matter collected from primary and secondary treatment is subjected to digester where the temperature is raised. This step produces methane gas which is used as a source of energy and the formation of nutrient-rich biosolids which can be further used for a biofertilizer.

(vi)    Tertiary treatment: in this stage the impurities from the water is removed and these water produced from this step is known as an effluent having very good quality and further can be used for various processes. The water after this step subjected to next step disinfection

(vii)    Disinfection: It is seen that after the primary, secondary and tertiary treatment there are some disease-causing organisms are still present in it so to remove these organism water is treated with the mixture of chlorine and sodium hypochlorite. After this treatment water can be used for drinking purposes.

(viii)   Sludge treatment: the solid sludge produced after these treatment steps is separated, treated, dried and can be used further for the agricultural purposes.