The treatment of first rainwater is for the vast majority of cases standardized, some companies carry out industrial processes that create wastewater with a high pollutant content.
In these cases, the first rain system alone is not sufficient and a filtration system is installed at the back of the system to absorb and retain residual pollutants.
The filtration process is a type of combined quartzite and granular activated carbon filtration.
The first stage performs the filtration and removal of suspended and sedimentable solids still present in the treated water of the first rain plant, the second stage allows to retain a series of pollutants such as COD, BOD, surfactants, residual chlorine, oils, solvents, organic substances, hydrocarbons, etc…
The industrial filters are composed of quartzite arranged on filter beds of different granulometry, the diversification of the size of the quartz allows to have an excellent degree of filtration of the first rainwater with a great capacity to contain retained solids.
The carbon used for pressure filtration of first rain water must have specific characteristics, the filtration of first rain water uses activated carbon with high absorbent capacity to reduce the periodic change and disposal of the product.
The filtration plants are made of PVC on frame, they are complete with valves for service management and backwash operations, all the operations of the first rain water filtration can be supplied with automation and differential pressure reading, managed by PLC or even in manual version.
