Tips on rural domestic waste

1. How to classify rural domestic waste

With the development of society and the continuous improvement of economic level, people generate more and more domestic waste, among which rural domestic waste is particularly prominent. Mainly including batteries, light bulbs, pesticide bottles, paint buckets, waste mercury thermometers, expired medicines, ink cartridges, toner cartridges, non-degradable plastic products (ultra-thin plastic bags, agricultural film), etc. The amount of this kind of garbage is increasing year by year with the development of rural and urban-rural integration. This kind of garbage has the greatest potential harm to the rural ecological environment and requires special safe treatment. For example, button batteries contain toxic heavy metal mercury; rechargeable batteries contain harmful heavy metal cadmium; dry batteries contain mercury, lead, acid and alkali substances and other environmentally harmful substances. Waste plastic products are difficult to decompose, destroy soil quality, and reduce plant growth by 30%; they may contaminate groundwater after landfill; and burning can produce harmful gases. How to deal with rural domestic waste so that it can be truly harmless? What about the home we rely on for survival? We can't help but worry. Therefore, carrying out science popularization and enhancing farmers’ environmental awareness are the first issues to be solved. Because it is crucial to shape social participation and environmental awareness of social individuals and even social organizations through effective environmental education. Proper disposal of rural domestic waste requires the active participation and cooperation of rural residents. It requires environmental protection departments, news media and teaching units to go to the countryside to promote and popularize environmental protection knowledge. We must be good at combining and utilizing World Environment Day, World Earth Day, National Patriotic Health Month, etc., hang environmental protection slogans in public places, organize cadres, the masses, and students to carry out environmental sanitation cleaning, and use radio, television and other media to promote , organize environmental protection knowledge competitions and other activities with strong mass participation to attract the active participation of residents and gradually improve residents’ environmental awareness. The publicity and education of environmental protection awareness should start from the details closest to farmers' lives, so that environmental protection knowledge can be "zero-distance" contact with them in the form of small tips and tricks, so as to shorten the distance between knowledge and life, eliminate farmers' resistance, and improve the quality of life. Publicity effect.

The "rapid, harmless, residual-free, resource recycling and industrialization" treatment technology of urban domestic waste is referred to as the "LJ Five" treatment technology. This technology set: 1

Uniform feeding of urban domestic waste and automatic sorting system for bulky garbage; 2

Automatic bag breaking system for bagged garbage and automatic crushing system for organic matter; 3

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Urban domestic waste fully enclosed, mechanized sorting system; 4

Organic matter hydrolysis hydrothermal oxidation fertilizer making system; 5

Inorganic matter making building materials system; 5

Plastic refining or granulation system; 6

Pyrolysis, gasification and waste heat utilization system for non-recyclable combustibles; 7

Waste gas treatment system; 8

Eight major treatment systems including the sewage treatment system are integrated into one, which can process the municipal waste generated in various places on the same day and produce products on the same day. After this technology was successfully applied to waste treatment plants in Guangdong, Zhejiang, Yunnan, Guizhou, Hebei, Liaoning, Shanxi and other places, obvious economic and social benefits have been achieved in various places, and the resource utilization of waste treatment has been maximized. In terms of industrialization, experts unanimously believe that this technology uses garbage to process garbage, meets the requirements of circular economy development, and represents the development direction of China's garbage disposal industry.

2. Classification of rural domestic waste

Among the existing methods of processing rural domestic waste, the following four methods are more common.

1. High-temperature aerobic composting technology

Composting is a metabolic process that uses microorganisms to degrade organic matter in garbage. The organic matter in garbage is decomposed into stable organic residues through a high-temperature process. The aerobic composting process usually consists of pre-treatment, main fermentation, post-fermentation, post-treatment and storage. When the organic matter content in the garbage is greater than 15, composting can make the garbage harmless and reduce its volume. Garbage compost can be used in agricultural production to increase the organic matter content of the soil. Therefore, the resource utilization benefits of the garbage composting method are significant, but composting requires high organic matter content and low heavy metal content in the garbage.

2. Biomass gasification technology

This technology utilizes the abundant organic waste resources in rural areas, such as straw, firewood, chaff and other wastes, and pyrolyzes them at high temperature. Combustion produces combustible gas, which has many advantages: high energy conversion rate, low energy consumption, long combustion time, large and stable firepower, and no pollution during combustion. It can not only improve rural production and living environment, but also save resources and energy. The organic waste purification furnace using this technology is easy to use, low in cost, and has three major functions: cooking, heating, and showering.

3. Vermicomposting technology

The basic principle of vermicomposting technology is to take advantage of earthworms’ scavenging, wide feeding habits, large food intake, and their digestive tracts that can secrete proteases and lipolytic enzymes. , fiber decomposing enzymes, chitinase, amylase and other enzymes, the organic solid waste that has been fermented to a certain extent is fed as food to earthworms and converted into physical and chemical substances through the digestion and metabolism of earthworms and the extrusion of the earthworm digestive tract. and feces with good biological properties, so as to achieve the purpose of harmlessness, reduction and resource utilization.

4. Anaerobic fermentation technology

Anaerobic fermentation method is to use organic matter in an anaerobic environment to produce combustible gas - biogas through microbial fermentation, and convert organic matter into energy. As domestic fuel, biogas and biogas residue are high-quality fertilizers. This method fully utilizes organic matter resources. The raw materials for fermentation are mainly human, livestock and poultry manure. It has the advantages of waste recycling, convenient management, low investment, and easy operation, and can be easily promoted and used in rural areas.

3. Scientific knowledge involved in the treatment of domestic waste in rural areas

The integrated technology project for the harmless treatment of domestic waste is led by the Guangzhou Institute of Energy, Chinese Academy of Sciences, and is presided over and implemented by Chief Scientist Researcher Chen Yong. The "Municipal Domestic Waste Resource and Energy Comprehensive Integrated Technology Demonstration Project" completed in conjunction with the Chengdu Institute of Biology, Chinese Academy of Sciences, is one of the 100 scientific and technological innovation projects in Guangdong Province.

This demonstration project was built in Boluo County, Guangdong Province, with a total investment of 22.85 million yuan and a total investment of 22.85 million yuan. It is a 200 tons/day energy self-sufficient urban domestic waste comprehensive treatment and utilization system. The first phase of the project will process 54,000 tons of domestic waste annually and produce 18,000 tons of organic compound fertilizer. The problem of urban garbage disposal has affected the national economy and people's livelihood, and the increase in garbage production has seriously harmed the environment.

my country's garbage stockpiles have reached 6 billion tons over the years. In 1997, the country's annual garbage output reached 140 million tons, growing at an annual rate of 8-10%. So far, most cities in our country have Domestic waste is still mainly piled in the open and landfilled, which not only takes up valuable land resources, but also causes serious secondary pollution to the environment. Research on comprehensive processing technology is imperative.

The main obstacle to the resource utilization of garbage is that the composition of the garbage itself is complex and difficult to utilize. On the other hand, the research and development of related technologies has not kept pace. Existing utilization technologies often adopt a single mode (such as incineration to generate electricity) and use the same method to treat different waste components, resulting in a large amount of consumption in the treatment process itself and poor economic efficiency. .

Therefore, research on key technologies for comprehensive treatment based on local conditions and different waste compositions is of great significance to fundamentally solving the waste problem and is a major event related to the national economy and people's livelihood. The demonstration project has a rigorous concept and comprehensive technology, leveraging strengths and avoiding weaknesses. Municipal waste treatment at home and abroad mainly uses landfill, composting, incineration and other methods. Among them, landfill technology occupies a large area; composting technology has the disadvantages of volume reduction, volume reduction and low degree of harmlessness; The use of waste incineration technology has a high degree of reduction, but the investment is huge.

Therefore, simply relying on certain technologies to deal with garbage is not the fundamental method to solve the garbage problem that is suitable for China's national conditions. Based on the characteristics of my country's urban domestic waste, this project starts from the perspective of "garbage is a misplaced resource" and develops new technologies and processes for waste treatment and resource utilization that save investment, have high processing efficiency and are low-cost--- Energy self-sufficient comprehensive treatment and utilization system for municipal solid waste.

According to the composition of my country’s garbage and the differences in the physical and chemical properties of each component, different garbage treatment technologies are organically combined to achieve the goals of volume reduction, weight reduction and harmlessness while reducing treatment costs. to the lowest possible extent and to comprehensively utilize waste resources to the greatest extent possible. A variety of technologies are applied at the same time, and the process is scientific and reasonable. Based on the study of the composition of domestic waste in Boluo County, the researchers of this project proposed the methods of sorting, organic waste fermentation, fertilizer processing, and pyrolysis of combustible materials-incineration. System integration technology that combines , gasification power generation, inorganic waste landfill and other processes: (1) The pre-sorting process separates municipal solid waste and recovers recyclable materials, such as renewable plastics, metals, waste paper, and glass; The sorted combustibles are incinerated; the sorted decayable organic waste is fermented, and the processed organic waste is produced into organic fertilizer; inorganic waste can be used for landfill, road paving or soil improvement (fine inorganic waste).

(2) Fermentation process Urban organic waste can be made harmless and mature through the action of microorganisms, and can be produced into organic fertilizer to provide organic fertilizer for agriculture. The rotten organic waste comes from spontaneous combustion. , and return to nature, thus maintaining the ecology of nature. This process can use rapid aerobic fermentation, high temperature post-ripening, and a processing cycle of 15 days.

The waste gas generated by closed fermentation is concentrated and discharged at a high level. The exudate produced during the fermentation process is recycled and no waste water is discharged. (3) Organic waste processing and fertilizer making technology. The way out after urban organic waste is processed is to produce fertilizers. The smooth marketing of fertilizers and the wide range of their use make waste treatment smooth and will also obtain certain economic benefits.

In terms of product quality, in addition to the quality of compost, the marketing of fertilizers and their scope of use, the processing of organic waste is also important. The treated organic waste is processed into fine powder fertilizer through secondary screening, coarse compost production or drying. The fine powder fertilizer can be used in paddy fields and dry land, and can be applied to various crops.

In addition, it can also be produced into organic and inorganic compound fertilizers, which not only have obvious yield increase effects but also improve the utilization rate of chemical fertilizers. (4) Incineration process The characteristic of incineration is rapid volume reduction, which is suitable for the treatment of combustible organic waste. This treatment technology uses the combustible organic matter separated during the sorting process for incineration.

Since the waste used for incineration has a low moisture content and a high calorific value, no additional auxiliary fuel is needed during incineration. The heat generated is used for the energy required for fertilizer drying, which can save energy. This process uses pyrolysis incineration technology to reduce the volume and volume of combustible organic waste.

Pyrolysis incineration is an advanced incineration technology that has begun to develop internationally. This technology takes advantage of the high volatile content of organic matter in garbage. First, the garbage is pyrolyzed (or gasified), and then the volatiles are released and then burned in the gas phase.

Through pyrolysis gasification and incineration, the dust, NOX, SOX, HCl, etc. in the flue gas are processed by dust removal, water washing, etc. to ensure that the tail gas emissions meet the standards. (5) The gasification power generation process adopts the waste gasification-internal combustion engine power generation technology of the Guangzhou Institute of Energy, Chinese Academy of Sciences. Its principle is the same as pyrolysis (gasification) incineration.

Combustible gas burns at high temperature in an internal combustion engine, which can completely burn harmful macromolecular organic matter and generate small-molecule harmless substances such as CO2 and H2O. This process is characterized by small installed capacity, low investment, and flexible and convenient start-up.

This process is a key link in reducing production costs. (6) Landfill process The landfill part of this system utilizes the original landfill facilities.

Technological innovation overcomes difficulties. Technology integration uniquely solves a series of key scientific and technological problems. Mathematical simulation of pyrolysis incineration and the amplification effect of pyrolysis incineration and gasification equipment; organic waste gasification power generation process research and equipment development; formation mechanism and control method of pollutants in the heat treatment process; sorting, composting, and pyrolysis incineration heating , gasification power generation, water and gas slag purification and other technology integration, optimization and control research.

It runs through the original unit processing technology. Pyrolysis incineration is a waste incineration technology. Based on previous research, our institute has independently developed strong cyclone pyrolysis incineration.

4. How should rural domestic waste be classified?

According to the actual situation of rural domestic waste, domestic waste can be divided into 4 categories according to the treatment and disposal methods or the possibility of resource recycling. kind.

(1) Compostable (organic matter): The main components are kitchen waste and other domestic organic matter waste. The treatment directions are livestock and poultry consumption, direct return to fields, composting, use as fuel and production of biogas. (2) Inert materials (inorganic matter): refers to cinders, construction waste, etc. The treatment methods are road construction, embankment construction, construction filling and landfilling.

(3) Recyclable waste: including waste plastics, paper, glass, metal, waste furniture and electrical appliances, fabrics, leather and rubber, etc. The treatment method is to use economic means and recycle. (4) Hazardous waste: such as pesticide bottles, expired medicines, batteries, lamps, paint buckets, etc., strengthen management and centralize safe treatment.

5. How to classify rural garbage

In the garbage sorting field, in a large area, more than a dozen sorting workers weighed the sorted and packaged garbage. After loading, a large forklift in the garbage factory shovels the waste that needs to be landfilled into the cleaning vehicle, and the entire garbage sorting process proceeds in an orderly manner.

Garbage classification will be an important part of garbage treatment in the future. Currently, Guangzhou is promoting garbage classification throughout the city, but the effect is not obvious. It is difficult to sort garbage in cities, and it is even more difficult in rural areas. In this case, Zhongluotan Town, Baiyun District, Guangzhou has adopted a compromise method: setting up garbage transfer points, that is, through transfer points, the town’s garbage is collected. Sorting yard and then sorting. Garbage classification map

In conjunction with the ongoing village sweeping and town transportation project, a garbage sorting site is established to classify garbage to maximize the rational use of waste resources. Zhong Luotan's approach is the first of its kind in Baiyun District . This method not only recycles valuable waste resources, reduces landfills, protects the environment, and allows resources to flow back reasonably, but also establishes a more scientific long-term mechanism for waste disposal, which is clean, environmentally friendly, and resource-saving.

In addition, Zhongluotan Town also operates the garbage sorting field through a market-oriented operation model of bidding, contracting the garbage sorting field to a professional cleaning company in the form of bidding. Market-oriented operations cannot solve all problems. At present, Zhongluotan Town is mainly responsible for the supervision and coordination of enterprises and the collection of cleaning fees after getting rid of the heavy garbage transfer.

The town’s garbage compression stations are located in Liangtian and Bamboo areas, both far away from the garbage sorting site. Since the sorting site is not equipped with a garbage compactor, the garbage that needs to be landfilled needs to be reloaded and transported to two garbage compression stations for reprocessing. The garbage disposal method in Zhongluotan Town provides a reference for rural garbage disposal.

6. What is rural waste (garbage)

Rural waste refers to domestic waste, livestock and poultry breeding waste, crop straw, forest product waste and other waste objects inside.

Among them, domestic waste includes ash, slag, commodity packaging, human and animal excrement (excluding large-scale industrial breeding excrement), used batteries, kitchen waste, gardening waste, etc. generated by rural residents in their daily lives. Waste, discarded daily necessities and other waste. Livestock and poultry breeding waste refers to solid waste such as excrement, urine, house flushing sewage, livestock and poultry house litter, discarded feed and scattered feathers, and also includes malodorous gases such as hydrogen sulfide and ammonia.

Crop straw is a general term for the residue left after the fruits are extracted from crops after processing. As for Zhejiang Province, there are many types of crops, including rice, wheat, corn, beans, potatoes, melons, oil crops, cotton and sugar cane.

The straw and rice husk after the rice is taken out are called straw. Rural forest product waste mainly includes discarded wooden furniture, wooden buildings (such as wooden doors and wooden windows), wood shavings, sawdust and disposable chopsticks. In addition, discarded writing paper, paper drink boxes, etc. also belong to the forest. Product waste.

7. Tips on garbage classification

Judging from the methods of classifying domestic waste in various cities at home and abroad, they are generally based on the composition and production volume of garbage, combined with local garbage Classify resource utilization and processing methods. For example, in Germany, it is generally divided into paper, glass, metal, plastic, etc.; in Australia, it is generally divided into compostable garbage, recyclable garbage, and non-recyclable garbage; in Japan, it is generally divided into combustible garbage, non-burnable garbage, and so on. Today, domestic waste in China can generally be divided into four major categories: recyclable waste, kitchen waste, hazardous waste and other waste. Currently commonly used garbage disposal methods include: comprehensive utilization, sanitary landfill, incineration for power generation, composting, and resource return.

Recyclable garbage

Mainly includes five categories: waste paper, plastic, glass, metal and cloth.

Kitchen waste

Including leftovers, bones, roots, leaves, peels and other food waste

Hazardous waste

Including waste batteries, waste fluorescent tubes, waste mercury thermometers, expired medicines, etc. These wastes require special safe handling.

Other garbage

In addition to the above categories of garbage, including bricks, ceramics, slag, toilet paper, paper towels and other difficult-to-recycle waste, hygienic landfilling can be effective Reduce pollution to groundwater, surface water, soil and air.

8. What issues need to be paid attention to in the successful implementation of classified collection and treatment of domestic waste in rural areas?

my country's rural residents generally have a low level of education, and the distribution density of villages is low, especially in natural villages in mountainous areas and seaside areas. , to establish a domestic waste collection, transportation, treatment and disposal system in rural areas of my country, we must pay attention to the selection of collection and transportation equipment, the planning of transportation routes, and the investment of system operating funds.

In addition, in order to ensure the normal and sustainable operation of the system, it is necessary to continuously increase environmental protection publicity and improve the environmental awareness of villagers. Generally speaking, the following issues need to be paid attention to in order to successfully implement the classified collection and treatment of domestic waste in rural areas.

(1) In view of the current situation of disorderly discharge of garbage in rural areas, overall consideration should be made based on the characteristics of rural population density, including collection and transportation costs, resource recycling and classification processing, to establish a life style suitable for the current rural situation. Waste source sorting and classification collection and transportation system. On this basis, the garbage on both sides of rural roads, rivers and around farmers' houses are cleaned up and transported to counties (cities) for processing through township transfer stations.

In addition, the development and promotion of cost-effective rural domestic waste recycling technologies should be increased, such as waste fermentation to recover biogas, composting to produce organic and inorganic compound fertilizers, etc. (2) Appropriate funding sources need to be found to ensure the continuous and stable operation of waste classification work.

The costs required for the sustainable and stable operation of the garbage collection and transportation system are difficult to maintain with financial support from villages and towns alone. Due to insufficient financial investment, the garbage collection and transportation equipment and cleaning personnel in some places are uneven.

Therefore, the financial department must arrange special funds for the collection, transportation and disposal of rural garbage every year for the construction of sanitation facilities and the operation of the sanitation system. (3) Strengthen management and ensure that management is in place.

When it comes to the classification, collection, treatment and disposal of rural domestic waste, we should pay attention to the leading role of ***, invest in the purchase of garbage collection devices, special vehicles for cleaning and transportation, and build garbage transfer stations, which will be managed by the town government. , a management and operation model in which villagers actively participate. (4) Improve villagers’ environmental awareness.

Villagers are the first executors of the classified collection of domestic waste. Improving the villagers' environmental awareness and strengthening the villagers' awareness of garbage classification are crucial to the successful implementation of the classified collection of domestic waste. At the same time, attention should also be paid to determining classification names based on local living customs, villagers' habits, and economic development levels. Artificial over-subdivision will increase the difficulty of the work and reduce feasibility.

In daily life, items that can be reused should be reused, and waste that cannot be reused but can be sold as scrap (such as glass bottles, cans, milk bottles, old rain boots, sandals etc.) etc. should be collected.

However, generally speaking, poor sales channels have weakened the enthusiasm of rural residents to sort and collect domestic waste to a certain extent.