Question:

(a) Explain the precautions that should be taken by plant operators while handling chlorine gas used in disinfection of wastewater.

(b) Show why disinfection of sludge is important and list seven ways how disinfection of sludge can be achieved.

(c) In various countries, there are still concerns from experts and local communities about the environmental impact of incinerators.  Consider the following two types of emissions produced by these waste treatment facilities:

(i) Gas phase emission
(ii) Particulate emission

State one possible major problem associated with each emission. Provide relevant solutions to the problems stated.