biochar and activated carbon, as carbon-rich porous materials, have wide environmental applications. in the present research, rice husk (rh) was used for preparation of biochar at 400, 600, and 800 °c under simple pyrolysis, physically-activated carbon with water steam, chemically-activated carbon with potassium hydroxide (koh), and physiochemically-activated carbon with koh and steam. physical...

the effluent quality of a sewage treatment plant using activated sludge process and finally secondary treatment depends on the flocculation efficiency and settling of the flocs. the survey of various treatment processes in water and wastewater treatment shows that temperature and ph are the important factors affecting efficiency of flocculation and settling properties. this study was performed ...