History of sewage treatment and environmental protection

(3) Maintenance of imported equipment and development of spare parts

Due to the large number of imported equipment into the sewage treatment industry, after several years of operation, the equipment will gradually appear damage of varying sizes, especially the maintenance and normal overhaul after the claim period. This requires technical personnel with professional skills to carry out, if you ask foreign experts to repair, maintenance costs will be greatly increased it is difficult to accept, if the imported equipment can maintain normal operation, it is necessary to train domestic professionals for the maintenance of imported equipment, so that they master maintenance skills to meet the maintenance standards of imported equipment. With the maintenance of professionals also have enough spare parts, especially some of the equipment to be eliminated will be introduced to China, spare parts will not be produced abroad, you need to domestic mapping, processing and manufacturing, only in this way can the imported equipment play its role, otherwise the damage of equipment, the lack of parts will affect the normal operation of the sewage treatment plant.

(4) There is a gust of wind in the selection of sewage treatment process, and the popular process is not selected according to the actual situation of the region

The choice of popular process is in the choice of sewage treatment process, the emergence of the simple pursuit of new technology, the pursuit of fashionable technology, do not consider the inlet water quality in the region, the water treatment amount and the use of effluent problems, in some sewage treatment plants have been built in our country, the inlet water quality is relatively low, but also choose AB method, the results can not be fully utilized, resulting in idle facilities and equipment. In some areas, the treated recycled water is directly used for agricultural irrigation, but also over-emphasis on phosphorus and nitrogen removal, the adoption of A/A/O method, increasing the construction investment and increasing the daily operating costs, and some individual areas in the construction of sewage treatment plants, see what the wind blew what process to take.

(5) The reclaimed water after sewage treatment is not fully utilized

Huge investment in the construction of sewage treatment plants, the treated recycled water can not be fully utilized, and even some areas will be treated recycled water and untreated sewage mixed together, and some areas do not recycle recycled water but discharged into the sea resulting in a waste of fresh water resources. At present, the world's fresh water resources are extremely scarce, and China's fresh water resources occupy the 121st place in the world, and the per capita fresh water occupancy is only 2000 m3.

(6) The sludge is not really harmless, and there is no way of final disposal

After the sewage has been treated by various processes, the effluent has reached the discharge standards stipulated by the state, but the sludge generated in the sewage treatment process has not been properly disposed of, and will cause secondary pollution to the environment. In some areas, the sludge does not go through harmless treatment, the sludge is shipped out, and it is not clear where the final place of the sludge is. In some areas, although the sludge has been digested and treated, the sludge has been stacked off-site and arbitrarily taken away. In some areas, the sludge is dried for agricultural fertilizer, and whether the heavy metal content is up to standard is rarely considered, and the analysis of how much harm to crops is insufficient. The national environmental protection department prohibits the sludge as a fertilizer for vegetable fields and rice fields, and as a agricultural fertilizer for dry fields, the composition of the sludge needs to be analyzed, and heavy metals and toxic substances can be used only if they do not exceed the standard. As a green fertilizer, sludge should be recognized by the garden department, and can be used only after tracking and analysis by the monitoring department. In short, if the sludge does not have the ultimate disposal way, it is a hidden danger of re-pollution to the environment.

(7) There is no deodorization device in the sewage treatment plant

Sewage treatment plant inlet pool, grilles, sedimentation tank, initial sedimentation tank and sludge storage tank of sludge treatment system, dewatering room (except centrifuge) will produce serious odor, not only affect the health of operation personnel, but also bring pollution to the living environment of surrounding residents, especially some early construction, the surrounding used to be farmland, pools, and sewage treatment plants far from the urban area. At present, it has become an urban area, built houses around the sewage treatment plant, formed a residential area, and the people around the sewage plant have suffered harm, and should solve the deodorization device through multiple channels, because the sewage treatment plant itself is an enterprise that eliminates pollution and protects the environment.