Design inlet and outlet water quality
The water quality of the reclaimed water used for landscape environmental water shall comply with the provisions of the "Urban Sewage Recycling landscape Environmental Water Quality" GB/T18921-2002。The reclaimed water shall be used as urban miscellaneous water, and its water quality shall comply with the provisions of GB/T 18920-2002 in the "Water Quality of Urban Miscellaneous Water for Recycling of Urban Sewage"。见表2-2。
Table 2-2 Quality of landscape water for municipal sewage recycling (GB/ T18921-2002) (mg/L)
Treatment process:
1 Sewage Collection
The discharged sewage collects homogenization in the sewage regulating tank, and the barrier well is set up at the front of the regulating tank。
2 Hair trapping
The hair aggregator is arranged on the suction pipe of the sewage pump, and the requirements of the hair aggregator are as follows: 1. The effective water area of the filter net is equal to 2 of the cross section area of the connecting pipe.5 times;2. The aperture of the filter is 3mm。
3 A2/O system
The A2/O process is used, that is, the wastewater is first treated by anaerobic and aerobic treatment, and then enters aerobic treatment。Such a process can improve the biodegradability of organic pollutants in wastewater and, when properly run, can also achieve nitrogen removal。The effluent from A2/O tank is separated in the secondary sedimentation tank, and part of the sludge is returned to the anaerobic tank, the aerobic tank and the aerobic tank, and the remaining biochemical sludge is connected to the sludge tank。The effluent from the secondary sedimentation tank enters the intermediate tank for subsequent filtration oxidation reaction。
The biochemical effluent first passes through the sand filter tank, which is equipped with quartz sand。The device is mainly used to remove fine solid particles and other small impurities suspended in the water。This process uses a new type of efficient filter material, which is made of a variety of media mixed processing, with high strength, high filtration flow rate, convenient backwashing and stable and reliable effect, so that it can greatly enhance the filtration and purification function of the inlet water and improve the quality of the effluent。
The sand filter water is collected in the intermediate tank, raised to the precision filter through the lifting pump, and then enters the ultrafiltration system, which intercepts all the small suspended solids and microorganisms in the wastewater。
5. Oxidation and disinfection system
After sand filtration, the wastewater enters the advanced catalytic oxidation system, ozone gas is generated by the ozone generator, the reaction process adds catalyst hydrogen peroxide, and the advanced oxidation process almost removes all bacteria and organic matter in the sewage, ensuring that the effluent meets the reuse water standard。
6 Activated carbon adsorption system
Adsorption method is often used to remove organic matter, colloidal substances, microorganisms, etc。Activated carbon is the most commonly used adsorbent in water treatment, which has good treatment effect, small footprint, convenient management and renewable。At the same time, it also has a strong adsorption capacity for some metals and their compounds。The device does not simply use activated carbon adsorption, but a special treatment of activated carbon to increase the adsorption capacity of activated carbon, thus strengthening the adsorption effect of activated carbon, so that the water quality is improved。
The effluent adsorbed by activated carbon is collected in the reuse pool for later use。Variable frequency pump group is used for water supply。
