Garbage is produced every day. In addition to a small part for incineration, most domestic garbage should be treated by centralized landfill, which is also the main way to solve domestic garbage in most cities in China.
In the past, there were no environmental protection measures for simple landfill sites. They just dug a big pit in the open air, poured in and compacted the domestic waste, which can be described as "buried". This kind of extensive open-air landfill actually does great damage to the environment. The garbage piled up in the open air is easy to attract a large number of mosquitoes and flies, and breed a large number of bacteria and viruses at the same time; The gradually decaying garbage after landfill is easy to produce biogas, which will spontaneously ignite and explode if it is not careful; The putrid smell generated by garbage accumulation is everywhere and lasts for a long time, polluting the air far and near; Garbage and its rotten leachate will pollute soil and groundwater sources and become pollution sources.
With the strengthening of environmental protection awareness and the progress of technology, people realize that garbage must not be "buried". Therefore, the simple landfill is gradually developed into a controlled landfill equipped with some environmental protection facilities, and then the controlled landfill is upgraded to a sanitary landfill that can control leachate and waste gas, which solves the problem of secondary pollution.
The basic concept of sanitary landfill construction is to use a synthetic material (plastic) liner to isolate the garbage from the environment, and then "bury" the garbage buried every day to separate it from the groundwater, keep it dry and avoid contact with the air as much as possible. Under such conditions, garbage will not decompose in large quantities.
Therefore, the site selection of the landfill site is particularly particular, requiring that the formation rock should be as impermeable as possible; Keep away from rivers, streams or wetlands to ensure that any possible leakage from the landfill will not enter the groundwater or watershed; Stay away from the nesting areas of local birds or migratory birds, and away from fishing grounds
In addition, it is also extremely important to build the structure of the landfill site in a standardized manner and use qualified materials, so as to ensure that the landfill will not cause environmental pollution; Even if it rains, the rain will not seep into the garbage; The biogas produced by landfill can be led out in time and utilized; Perforated pipes are all over the landfill, so that all the landfill leachate can be recycled; Cover the top layer of the landfill with soil and plant turf. Through these effective measures, the landfill can change the dirty, smelly, polluted and toxic situation in the past, especially it will not pollute the surrounding environment.