Mainly physical treatment method, biochemical treatment method and chemical treatment method, biochemical treatment method is often used, the mainstream treatment method depends on the quality of the treated water and the receiving body of water, the general urban sewage mainstream treatment method for the biochemical treatment method, such as activated sludge, mbr and other methods.
White Pollution :
White pollution is unique to China's urban environmental pollution, in a variety of public **** places can be seen everywhere in a large number of discarded plastic products, they come from nature, made by humans, and ultimately attributed to nature is not easy to be consumed by nature, thus affecting the ecological environment of nature. From the perspective of resource conservation, plastic products should be recycled as much as possible since their main source is petroleum resources which are facing depletion, but it is difficult to do so under the current market economic conditions since the production cost of recycling is much higher than the direct production cost at this stage. In the face of the increasingly serious problem of white pollution, people want to find a substitute for the performance of existing plastics, but does not cause white pollution of plastic substitutes, degradable plastics came into being, this new functionality of the plastic, which is characterized by a certain service life in the discarded, in the specific environmental conditions, due to the chemical structure of the obvious changes, causing the loss of certain properties and changes in the appearance of the degradation of the natural environment is harmless or less harmful. The natural environment is harmless or less harmful. For example, starch-filled plastics, first of all, the starch contained in a short period of time by the microbial secretion of amylase in the soil to rapidly decompose and generate voids, resulting in a decline in the mechanical properties of the film, and at the same time, the formula of the addition of self-oxidizing agent and the reaction of the metal salts in the soil to generate peroxides, so that the chain of polyethylene breaks down and degraded into a small fragment that is easy to be devoured by microorganisms to be consumed by the natural environment, and at the same time, play a role in improving the soil.
The earth is our home, and this home is being surrounded by garbage. As the masters of the 21st century, we can't just worry and complain, but we have to act and act green. Garbage is not useless, and waste products are not useless. Garbage resources and recycling is not technically difficult, the difficulty lies in the waste casually discarded, mixed and piled up to become garbage; therefore, as educated civilized people of the new century, we should participate in the "hand up" garbage source classification activities, in order to purify our living space to do a little dedication, dedication and a piece of love.
Living garbage is a by-product of human life. With the rapid development of social economy and the high concentration of urban population, the production of living garbage is gradually increasing. General household garbage can be divided into five categories such as waste paper, plastic, glass, metal and biological waste. The main hazards of garbage to human life and the environment are:
First, occupying too much land. Piles of garbage in the outskirts of the city, encroaching on a large amount of farmland. Now the average annual production of garbage per person in Beijing is 440 kilograms, the city's annual production of about 4 million tons, equivalent to two and a half Jingshan. There are already more than 4,500 garbage dumping sites in Beijing, covering more than 10,000 mu of land. Garbage also stays in nature for a long time: cigarette butts and wool fabrics for 1-5 years; orange peels for 2 years; painted wooden boards for 13 years; nylon fabrics for 30-40 years; leather for 50 years; cans for 80-100 years; plastics for 100-200 years; Glass 1000 years. For this reason, we should not only create less garbage, but also pay attention to the classification of garbage, recycling and turning waste into treasure. Less disposable chopsticks, cups, lunch boxes and other products, more reusable products, reduce the consumption of valuable forest resources; less plastic bags, shopping bags, reduce the harm of urban "white pollution"; buy non-fluorine refrigerators, air conditioners and other environmentally friendly appliances, to protect the ozone layer of the atmosphere; less use of high-concentration detergents, the use of non-phosphorus laundry detergent, to reduce water pollution. The first is to reduce water pollution.
Secondly, it pollutes the air. Garbage is a complex mixture of ingredients. In the transportation and open storage process, the decomposition of organic matter to produce a bad smell, and to the atmosphere to release a large number of ammonia, sulfide and other pollutants, which contains organic volatile gases up to more than 100 kinds of these releases contain many carcinogenic, teratogenic substances. Plastic film, paper and dust are flying with the wind to form "white pollution".
Third, pollution of water bodies. Harmful ingredients in the garbage are easily washed into the ground water bodies by rain, in the garbage dumping or pit filling process will produce a large number of acidic and alkaline organic pollutants, while the heavy metals in the garbage will be dissolved out. The exudate generated by the garbage pollution source will enter the underground water body through soil infiltration; the garbage is directly discarded into rivers, lakes or oceans, which will cause more serious pollution. You see: Summer Palace, Beihai floating on the water surface of the plastic bottles and lunch boxes, Fragrant Hills, Badaqi forested mountain paths scattered and tree branches hanging on the plastic bags, bread paper, etc., some tourists only want their own convenience, resulting in tourism environmental pollution. If the animals accidentally eat the white trash will not only hurt their health, and even lead to death.
Fourth, soil slagging. Garbage directly applied to agricultural land, or only after simple treatment for agricultural land will destroy the soil's granular structure, physical and chemical properties and water retention, fertilizer capacity. In particular, plastic bags, plastic sheeting, if buried in the farmland, the roots of crops can not grow, the farmland will be reduced, the food available for people to eat will be reduced.
Fifth, fire hazards. Garbage contains a large number of combustible materials, in the natural stacking process will produce methane and other combustible gases, in the case of open flame or spontaneous combustion easy to cause fire. With the increase in the organic content of municipal waste and scattered from the open piles into centralized storage, and in the long-term storage of only a simple cover resulting in garbage methane gas hazards are becoming increasingly prominent, garbage explosions continue to occur, resulting in significant losses.
Sixth, the nest of harmful organisms. Garbage not only contains pathogenic microorganisms, but also for rats, birds and mosquitoes and flies to provide food, habitat and breeding places, but also the root cause of infectious diseases.
In summary, the seriousness and urgency of the problem of urban garbage is obvious. To make these garbage into treasure, we need to do a good job of recycling and utilization of garbage. Do you know? Recycling 1 ton of waste paper can produce 800 kilograms of good paper, you can cut 17 trees, can save more than half of the paper energy, reduce water pollution by 35%; 1 ton of waste plastic can be at least 600 kilograms of gasoline and diesel back to the refining; with the waste glass to reclaim glass, not only can save quartz sand, soda ash and other raw materials, but also electricity; smelting metal with waste metal can save a lot of energy consumption, but also can reduce air pollution; and Some of the peel, eggshells, leaves, leftovers and other kitchen waste, can be processed by composting and fermentation methods, into green fertilizer and so on.
Therefore, we should vigorously carry out the publicity and education of garbage source classification and collection through various mass media such as TV, radio, newspaper and information network; urgently formulate the laws and regulations on garbage classification, collection and treatment suitable for the national conditions, and strictly enforce them; consider carrying out the pilot work of garbage source classification and collection in some units in depth; and further discuss with all of you to improve the management methods, so that the garbage source classification and collection can be carried out universally as soon as possible. source-segregated garbage collection as soon as possible to be carried out universally. Let's work together to promote the separation and recycling of garbage, remove garbage pollution, turn waste into treasure, and conserve resources. So that Beijing can be a new look to win the 2008 Olympic Games hosting rights, but also to provide ourselves with a beautiful and healthy living space.