Feedwater of boiler without treatment usually consists of suspended solids such as bacteria, silt and mud. When the suspended solid is left in the feedwater, this substance can certainly lead to difficulties, like deposits or foaming in steam boiler.
Removal of suspended solids can be performed by filtration or clarification process. One popular system requires the two processes; the water is initially distributed via a clarifier that eliminates almost the entire suspended solid, then the rest is eliminated by filter.
To carry out the clarification process, a flocculent assist is put together with raw water in both water feed series and in the “quick mixture area” of the clarifier. Main clarification takes place in “quick mixture area”, in which compact solids are made. The solids raise larger in the “slow mixture area” and also settle in “settle area”. The producing sludge is eliminated through base of device though clarified water is moved through the top part by stuffed towards a launder (a unit which features significantly such as a pool skimmer). A rake at base of clarifier goes gradually via settled sludge to maintain water from solidifying.
Other removal of suspended solids such as filtration could be performed some various methods. the majority of popular filters are granular filters medium, created from garnet, anthracite, and sand. Different kinds of filters, such as strainers, sock filters, and cartridge filters are employed in several installations. Filter bed level, filter medium option, and some other design variables are established by the standard of boiler water specifications.