The cost of landfill is high, and the cost of treating one ton of garbage is about RMB from 200 yuan to 300 yuan. People consume a lot of resources, mass production and consumption, resulting in a lot of waste.
Can't we do something about the garbage? In fact, there is a way, and this is garbage sorting. Garbage classification is to put garbage into the source, and make it become a resource again through sorting, cleaning and recycling.
Judging from the classification methods of municipal solid waste at home and abroad, it is generally classified according to the composition and output of garbage, combined with the resource utilization and treatment methods of local garbage. For example, Germany is generally divided into paper, glass, metal, plastic and so on. Australia is generally divided into compostable garbage, recyclable garbage and non-recyclable garbage; Japan is generally divided into combustible garbage, nonflammable garbage, and so on.
At present, domestic garbage in China can be roughly divided into four categories: recyclable garbage, kitchen garbage, harmful waste and other garbage. At present, the commonly used garbage disposal methods mainly include comprehensive utilization, sanitary landfill, incineration and composting.
1. Recyclable garbage mainly includes waste paper, plastic, glass, metal and cloth. Waste paper: mainly includes newspapers, periodicals, books, various wrapping papers, office paper, advertising paper, cartons and so on. However, it should be noted that paper towels and toilet paper are too water soluble to be recycled. Plastics: mainly include all kinds of plastic bags, plastic packaging materials, disposable plastic lunch boxes and tableware, toothbrushes, cups, mineral water bottles, etc. Glass: mainly includes all kinds of glass bottles, broken glass pieces, mirrors, light bulbs, thermos bottles and so on. Metal objects: mainly include cans, cans, toothpaste skins, etc. Cloth: mainly includes discarded clothes, tablecloths, towels, schoolbags, shoes, etc. Comprehensive treatment and recycling can reduce pollution and save resources. If every 1 ton of waste paper is recycled, 850 kilograms of paper can be made, 300 kilograms of wood can be saved, and pollution is reduced by 74% compared with the same output; Every 1 ton plastic beverage bottle can recover 0.7 tons of secondary raw materials; Every recovered 1 ton of scrap steel can produce 0.9 tons of steel, which saves 47% cost compared with ore smelting, reduces air pollution by 75%, and reduces water pollution and solid waste by 97%.
2. Kitchen garbage includes food garbage, such as leftovers, bones, roots and leaves. After in-situ composting by biotechnology, 0.3 tons of organic fertilizer can be produced per ton.
3. Hazardous wastes include waste batteries, waste fluorescent tubes, waste water silver thermometers, expired drugs, etc. These wastes need special safety treatment.
4. Other wastes include bricks and tiles, waste residue, toilet waste paper and other wastes that are difficult to recycle. Sanitary landfill can effectively reduce the pollution of groundwater, surface water, soil and air.