classification by using
1. after treatment ,can reach the The standard of drinking water. it can realize the direct recycling water resources..
this treatment way can be using in the area that is bad lack of water, but it is really high invest, and the Process si complex too.
2. after treatment, can reach non-potable water standard,mainly using in the filed that is not drectly direct contact human body. usually , in the system it will be added teh softener, RO, EDI device..etc so that the output water can be the softened water, pure water, ultrapure water.. this industrial recycling can save capital and also can protect the enviroment.
classicification by the treatment method
1. physical treatment
using membrane to filter, it is suitable for the water quality that change big.
this kind of system, it is compact-packaged and easy for handling, and the influence of load change is small.
the membrane filter is using via the out pressure, the separated solution when flowing along the membrane surface. the solvent and Low molecular weight material, inorganic ions will go through the high pressure side to the low pressure side and will be ldischarged as filtrate; and the Macromolecule substance and colloid particles and microorganisms will be retained by the UF membrane and concentrateed and discharged.
2. physical-chemical process
suitable for the Sewage water quality that change is large, usually it is processing by sand filter,activated carbon adsorption, Flotation, coagulation precipitation.etc.. it is processing with the hollow fiber UF membrane. with the Advanced-technology, compact structure, area occupied less, intermittent operation system, it is easy and simple for management.
suitable for the Organic matter content is high. usually it is by Activated sludge process, contact oxidation method, biological rotating disc..etc.. it can be using separatedly or together combine. such as Biological contact oxidation +Biological filter pool, Biological filter + activated carbon adsorption; biological rotating disc+ sand filter.
this kind of process is adapt to hydraulic load change ability, and Less output of sludge, and also , it is easy for operation.
recently, some countries and districts, they Excessively,develop & use water resources without restraint, and their environmental protection consciousness is poorer, this un-restraint development will let the surface water and ground water have been polluted to different degree. this will let originally have good water quality of fresh water supply limited.
besides, the underexploited fresh water is far from the water supplier location. the investment cost too high , so in some disctric that is lack of water, they cannot expanded the capacity of water supply.
so the recycled water is mentioned when using the un-drinking water standard water,.
it is using the high grade gray water that is exported from daily and contraction using water ( not including the faeces water or the kitchen water), the high grade gray water (exclud faeces water) and the daily sewage water is resuing after collected and regeneration water treatment.
It can be using as ground clean, watering the flowers, wash the car, air conditioning, flush toilets, fire control cooling which are not directly contact to human body. this water is blow the city tap water drinking water quality criterion but higher than the Allow discharged into ground water wastewater discharge standard, so it is called recyle water.