According to the survey, the majority of small and medium-sized cities sewage treatment plant is impacted by the industrial waste water, 55% of the sewage treatment plant daily, weekly, or monthly hit from serious water quality.Water shock may deserve attention, when it rains (rain), sewage plants in water increased by more than 20% above the normal of seven, have four more than 50% of the countrys more than normal.In terms of sludge treatment, the small and medium-sized cities sewage treatment plant directly to the moisture content of 41.18% to 80% of sludge sanitary landfill, only a handful of sewage treatment plant in handling such as incineration and compost.Reclaimed water reuse, dosage of 76.67% of the sewage treatment plant back to zero.
Survey of city pipe network management fees and 47% needed if problems arise, temporary apply to the financial cost;Every year, only 25% of fixed maintenance cost budget, have a fixed with 17% of the cost of repair and renovation budget.About 60% of the city, the drainage pipe network management with no clear maintenance standards and specifications.The survey found that there are eight cities have drawn from sewage pipe network or pipe canal of untreated sewage water for irrigation, accounting for 47% of the total number of cities and towns.According to the survey, 58% of the industrial park sewage access to the municipal sewage pipe network and municipal sewage plant, enterprise sewage treatment station often have excess emissions of 52%.
Sewage treatment equipment using membrane bioreactor (MembraneBioreactor, hereinafter referred to as the MBR) technology is combined biological treatment with membrane separation technology is a kind of new technology, to replace the traditional process of the second pond, it can efficiently solid-liquid separation, get the stability of the direct use of water. But also to maintain a high concentration of microorganisms in the biological in the pool, process less excess sludge, effectively remove ammonia nitrogen, suspended solids and turbidity water was close to zero, the bacteria and viruses in water is removed significantly and low energy consumption, cover an area of an area small. In the 70 s in the United States, Japan, South Africa, and many European countries had begun to use membrane bioreactor for sewage and wastewater treatment research. Its water from the sewage (such as shower drainage, drainage lavatory drainage, laundry, kitchen drainage, drainage, etc.) and cooling water. The toilet
Sewage after grille into regulating pool is entered into the bioreactor, lift pump by PLC controller open aerator oxygen filling, bioreactor effluent by the circulation pump into the membrane separation processing units, strong water returns to adjust pool, membrane separation of water chlorination after rapid mixing method (sodium hypochlorite, bleaching powder, chlorine tablets), enter the water in the pool of water storage tank.Backwash pump use wash in the pool to backwash of film processing equipment, processing water recoil sewage returns to adjust pool.Through biological reactor water level control to promote the opening and closing of the pump.Membrane unit filter operation and backwash operations can be automatic or manual control.When membrane unit need chemical cleaning operation, shut off the water valve and sewage circulating valve, open the medicine and pharmaceutical circulation valves, start liquid circulating pump, chemical cleaning operations.Has been built by the water reuse engineering are widespread in poor treatment effect and high operating cost, the problem such as facility covers an area of large, processing facilities operation is not ideal.So the urban water treatment in China is in urgent need to develop economic efficient applicable treatment technology and equipment. |