I. Overview

Fruit and vegetable waste refers to the injuries, diseases, residual leaves or secondary fruits peeled off during the production, harvesting, processing, transportation and sales of vegetables and fruits to improve their commercial properties, and their production accounts for more than 30% of the output of vegetables and fruits. . According to data from the National Bureau of Statistics, as of 2019, the sown area of vegetables in my country was 20862.74 thousand hectares, the total vegetable output was 721.0256 million tons, the fruit planting area exceeded 12 million hectares, the total output was close to 280 million tons, and the fruit and vegetable waste exceeded 300 million tons. . Fruit and vegetable wastes are rich in nutrients, but have high moisture content, are perishable, and breed harmful bacteria and viruses. Landfill treatment will produce a large amount of high COD, high ammonia nitrogen leachate, endanger the groundwater and the surrounding environment, and produce methane, nitrogen oxides and other greenhouse gases. Due to the high water content and low calorific value of fruit and vegetable waste, the cost of incineration is huge. Anaerobic biogas production cannot be industrialized due to its low output and unstable gas production. This project uses microbial fermentation technology to make it harmless and utilize resources while reducing its carbon footprint.

2. The company's process route

This project uses microbial fermentation to decompose the waxy layer and cell wall of the plant to release the water inside the cell, and then achieve solid-liquid separation through screw extrusion. After separation, the vegetable residues are combined with hay and other auxiliary materials to compost to produce organic fertilizer or bio-organic fertilizer. If the source of the fruits and vegetables is clean, the solid-liquid separation results in vegetable residues combined with hay, corn cobs and other auxiliary materials to make silage. The resulting vegetable wastewater from solid-liquid separation is fermented to produce plant enzymes by plant enzyme bacteria. The whole process realizes all resource utilization of fruit and vegetable waste.

Three, technical characteristics

Feature 1: Microbial fermentation breaks the wall

Technical features: strains that decompose waxy layer, pectin, cellulose, etc. are selected and cultivated to form a compound bacterial agent. Connect an appropriate amount of our company's wall-breaking bacteria to the broken-wall fermentation tank, control the appropriate temperature, and ferment for 1d~2d to release the water in the cells.

Feature 2: Recycling-Organic Fertilizer (Bio-Organic Fertilizer)

Technical features: high-temperature organic decomposing fungi are selected and bred to quickly increase the temperature of the pile to above 70°C, so that the materials are quickly decomposed. After dehydration, the vegetable residue is mixed with part of livestock manure and hay, and an appropriate amount of the company's high-temperature organic decomposing fungus is added for aerobic composting. The organic decomposing agent decomposes quickly, and the seed germination rate and germination index of the compost product are high.

Feature 3: Resource utilization-silage

Technical features: Fruit and vegetable residues from relatively fresh fruit and vegetable wastes are mixed with corn cobs, hay and other materials, inoculated with appropriate amount of silage starter of our company, and anaerobic wrapped silage. After silage, it will produce lactic acid, small molecule active peptides and other ingredients, and it is rich in probiotics. It is delicious and juicy. It is an excellent feed for cattle and sheep.

Feature 4: Recycling-plant enzymes (compound microbial fertilizer)

Technical features: Using the "anaerobic hydrolysis + lactic acid fermentation" process, the fruit and vegetable wastewater is hydrolyzed in the anaerobic stage to hydrolyze polysaccharides, proteins and other substances into monosaccharides, peptides, amino acids and other substances, which forms the basis for lactic acid fermentation. In the lactic acid fermentation stage, lactic acid bacteria are connected to convert the hydrolyzed monosaccharides and other small molecules into lactic acid. The product can be used as a soil conditioner for nutrient-poor or partial saline-alkaline soil; it can also be used together with irrigation water during crop planting to improve the soil microbial structure, produce plant growth-promoting factors, and improve the absorption efficiency of nutrients by plants. And it can directly provide quick-acting and slow-release nutrients to plants, reducing the amount of chemical fertilizers.

Feature 5: Low-carbon fermentation tank

The fermentation tank is the main equipment for biochemical wall breaking of fruits and vegetables. The effective volume of a single tank can reach 400m³. The effective volume of the fermentation tank needs to meet the fermentation time of materials ≥24h, which is combined according to the amount of fruits and vegetables. The tank body is equipped with auxiliary components such as feeding, material level alarm, liquid draining, and automatic discharging. In addition, the system also includes equipment such as spraying devices for bacterial agents, recycling equipment for fermentation broth, etc., which reduces consumption of bacterial agents and reduces operation and maintenance costs. The fermentation tank has no stirring and air supply devices, and has low energy consumption. It is a low-carbon product regardless of its manufacturing or operation process.

Feature 6: This process reduces the carbon footprint

While the process of processing fruit and vegetable wastes realizes almost all wastes as resources, the processing process greatly reduces greenhouse gas emissions compared with landfill incineration. Compared with wastewater treatment, the carbon footprint of wastewater recycling is significantly reduced.

Based on the annual processing of 270,000 tons of fruit and vegetable waste, the annual greenhouse gas emissions (in tCO2 equivalent) of the three fruit and vegetable waste treatment methods and the greenhouse gas emissions reduced by this process compared with the other two treatment methods are compared as shown in the table below Show: