The three format FRP septic tank can anaerobic ferment and filter domestic sewage, which is suitable for the transformation of latrines in rural construction. It seems that in the process of new rural construction, we are generally using three format FRP septic tanks.

The basic principle of the double urn and three format (improved three grid) sanitary toilet is to remove and kill parasitic eggs and bacteria and control the breeding of mosquitoes and flies by using the principles of precipitation caused by the proportion of parasitic eggs being greater than the fecal and urine mixture, and fecal sealed anaerobic fermentation, liquefaction, ammoniation, biological antagonism, etc. The three compartment septic tank adopts a three format fecal treatment facility, which is generally matched with the water flushing toilet, and is composed of fecal inlet pipe, compartment tank, fecal pass pipe, cover plate and other parts. In the process of use, it can prevent leakage and rainwater scouring. The sealing is relatively good. The size of the inflow pool cover is appropriate, and there is no discomfort in use. The quality is good, and it is not easy to be damaged. Three compartment septic tank products are relatively used to a certain extent. It can keep the fecal liquid relatively calm, reduce the water impulse, prevent the fecal skin floating on the fecal liquid level, and prevent the fecal slag and insect eggs sinking at the bottom of the pool. Prevent gas surge and blockage when entering feces. At the same time, it also reduces the later maintenance cost.

Three compartments are better. The structure and function of the third compartment septic tank. The feces flowing into the third compartment have generally been decomposed, and the bacteria and insect eggs have been basically killed and removed, which can be used for fertilization. The function of the third tank is mainly to store feces. The volume of the third pool is basically determined by the number of fertilization and the amount of fertilization each time. If the fecal water in the third tank is not used as fertilizer, but is directly exported for shallow soil filtration purification treatment, the volume of the third tank can be appropriately reduced. And the third can continue to play the role of the second pool