I. Overview

Perishable waste (food waste), also called wet waste, generally refers to the food waste generated in the production process of catering operators and unit canteens, as well as the perishable waste generated in family life, mainly including: Vegetable leftovers, vegetable stems, vegetable leaves, meat innards, husks and melon skins, etc.

The hazards that food waste may cause to the environment are mainly manifested in the following points: (1) Food waste has a high moisture content, is extremely perishable and causes acid and odor, breeds mosquitoes and bacteria, and causes disease transmission; (2) Food waste The content of medium fat is high, and it is easy to be used by illegal businesses to make "ditch oil"; (3) The kitchen waste is directly discharged into the sewer network, there is a waste of resources, and it is easy to cause the sewer pipe to block; (4) Kitchen waste Increasing the precipitation of leachate from landfills, polluting surface water and groundwater.

At present, the main treatment methods are: landfill, incineration and fermentation composting. At present, 65% of domestic garbage in the country is disposed of through landfills, and the landfill rate of waste in the central and western regions reaches about 80%, but this will cause odor problems and air pollution, and there will be serious secondary pollution. At present, about 30% of domestic waste in my country is processed by incineration, and the incineration treatment rate in the eastern region exceeds 50%. This method has high investment costs, low waste heat power generation efficiency, high cost, and incineration will cause air pollution; current fermentation composting It is mainly heated and fermented compost, which has the disadvantages of high energy consumption and low maturity.

2. The company's process route

Traditional food waste disposal methods can no longer meet the requirements of environmental hygiene and safety, and it is urgent to find a reasonable way to deal with food waste. The use of microbial treatment equipment to reduce the amount of waste, and the addition of microbial flora with special degradation functions to degrade organic substances, digest the food waste to realize the resource and harmlessness of the waste, and avoid the possibility of cleaning and transporting the food waste The secondary pollution caused by the problem of food waste has been effectively controlled at the source, and at the same time, the reduction of food waste treatment has been achieved, which has obvious social benefits and application promotion value.

The company uses room temperature degradation + high temperature composting technology to realize the recycling of organic perishable waste. The technology is more energy-saving, and the compost maturity is high, and the seed germination rate and germination index are high. This technology is not only suitable for centralized, all-in-one machines can realize decentralized disposal of all kinds of perishable garbage.

Table 1 Comparison of treatment technologies for organic perishable waste

Thermophilic aerobic fermentation

1. Technical Features

1. Breeding of medium and room temperature efficient perishable garbage degrading bacteria and mixed bacteria fermentation technology based on Gram staining microscopic examination technology.

The Gram staining microscopic examination technology scheme is adopted to obtain high-activity medium and normal temperature food waste degrading bacteria and high-yielding bacteria; the food waste simulation liquid is used to construct a mixed culture scheme and a mixed bacteria fermentation process is developed. By studying the decomposition rate of mixed strains on food wastes such as starch, protein and oil, a high-efficiency composite microbial degrading inoculum preparation program was obtained.

2. Breeding technology of thermophilic composting strains based on the law of substance transformation and the mechanism of biological characteristics during the composting process

Based on the substance conversion law and biological characteristics mechanism in the composting process, a high-efficiency thermophilic composting strain breeding program was obtained, and the quantitative relationship between the degradation rate and various factors was established. Based on the single-factor test method, the second universal rotation combination was designed and the energy was selected. The strains that adapt to high temperature and rapidly increase the fermentation temperature undergo mixed fermentation to obtain the optimal microbial degradation process.

3. Design scheme of intelligent modular equipment for efficient and automatic impurity removal and automatic microbial degradation

Using kitchen and other perishable waste as raw materials for real-time processing, based on the finite element analysis method, the automatic impurity removal and separation structure is optimized to realize the pulping of the kitchen waste while reducing the fragmentation of debris. By adjusting the screw pitch and speed , The spiral blade outer diameter structure meets the demand for the amount of kitchen waste treatment, and the intelligent kitchen waste treatment equipment control system is designed to realize the integrated treatment of automatic impurity removal, separation, and microbial degradation.

4. High-concentration perishable garbage sewage treatment technology and reclaimed water treatment technology

Based on the air flotation pretreatment method, the air flotation dosing agent and air flotation device are optimized to efficiently remove grease and suspended solids. By optimizing the anaerobic and aerobic bacteria agents and processes, the sewage can be discharged up to the standard. It is expected that the reuse rate is an optimized index, and a resource utilization strategy for waste water reuse is proposed, and a high-concentration perishable waste sewage treatment process and a treatment plan for reclaimed water are obtained.