Due to the long-standing food culture and dining habits, a large amount of kitchen waste seems to be a unique phenomenon in China. According to statistics, in 20 10, the annual output of kitchen waste in Beijing was about 630,000 tons, and the daily output was about 1750 tons. According to the statistics of Tsinghua University Institute of Solid Waste Pollution Control and Recycling, China produces no less than 60 million tons of kitchen waste every year.
Kitchen waste is not only large in quantity, but also rich in organic matter, high in water content, easy to rot and deteriorate, giving off stench and spreading bacteria and viruses. If mixed with other domestic garbage, it is easy to pollute other garbage, turn recyclable garbage into dirty garbage, lose its use value and increase the cost of cleaning and recycling. The kitchen waste produced by catering industry contains a lot of leftover soup and spoiled water, which is easy to leak during collection and transportation and affects the urban environment. Direct landfill treatment of kitchen waste will cause serious pollution to groundwater.
In the past, the treatment methods of kitchen waste were landfill and composting. Nowadays, sorting and high technology not only make it get rid of the hat of a big garbage collector, but also become a pioneer in turning waste into treasure. The main technologies of kitchen waste recycling are biological method and physical method. The biological method uses microbial fermentation technology to make fermented feed, and the physical method is to dehydrate, dry and disinfect kitchen waste to make dry feed. According to experts, according to the dry matter content, 50 million tons of kitchen waste is equivalent to 5 million tons of high-quality feed, and the energy contained is equivalent to the energy output of 6.5438 million mu of cultivated land every year, and the protein contained is equivalent to the protein output of 20 million mu of soybeans every year. In other words, if all the kitchen waste produced in China in one year is used, it is equivalent to saving about 6.5438+million mu of cultivated land. Facing the shortage of cultivated land and grain in China, we need to import a lot of grain and feed every year. Reasonable utilization of kitchen waste is an effective way to improve the utilization rate of resources and solve the food problem in China to some extent. Moreover, this utilization conforms to the characteristics of reduction, reuse and resource utilization, and is a vivid case of developing circular economy.
Every day, in a microbial resource recycling center not far from Shangdi subway station, trucks with the words BGB come in and out from here six times to recycle the garbage from more than 20 restaurants in the area. The kitchen waste, which was originally composed of soup and water, was transformed into golden yellow powder after more than six hours of high-temperature fermentation, which is a microbial fertilizer suitable for agricultural production. This method of decomposing Japanese biological bacteria into fertilizer and feed was introduced by Beijing Jiabowen Biotechnology Co., Ltd. to develop biological bacteria suitable for high-oil and high-salt foods in China. This technology is just like lactic acid bacteria can turn milk into yogurt. After 8 to 10 hour, the leftovers are turned into fertilizer by adding biological bacteria.
In 2008, this bacterial fertilizer extracted from the leftovers was applied to a 50-mu strawberry greenhouse, which not only greatly improved the taste and yield of strawberries, but also eliminated the headache of strawberry farmers. Covering 5000 mu of strawberry greenhouse in 2009. Although the cost per mu increased by 200 yuan, the average yield per mu increased by 800, reaching 1000 kg, and the yield increased by 30%.
This technology of extracting biological bacterial fertilizer from leftovers was also used in Beijing Olympic Games. Turning the kitchen waste in the Olympic Village into microbial fertilizer, and then providing strawberries and other fruits planted with these microbial fertilizers to the Olympic Village, forming a complete "circular economic chain of the table" has become a highlight of the high-tech Olympics.
Jia Bowen's demonstration at 13 Science Expo left a deep impression on everyone: there are two cracked eggs on a plate, and the yolk colors are obviously different. One is an ordinary egg, and the other is an egg laid by a chicken that eats BGB biological protein feed of our company. According to reports, this feed contains 107 beneficial bacteria, which is very beneficial to human body. Unexpectedly, this kind of feed is made from kitchen waste, which really turns waste into treasure.
20 10, Gaoantun kitchen waste treatment plant, the largest kitchen waste treatment plant in China, covering an area of 32 mu, was completed and put into operation. Here, by adding corn husks, peanut shells and some microbial agents, 200 tons of kitchen waste will be turned into animal feed or organic fertilizer every day, which will be supplied to large farms and planting bases without polluting the surrounding environment.
In the morning, a garbage truck full of kitchen waste drove into the factory. In the garbage unloading area, the kitchen garbage just shipped from the city is unloaded into a huge semi-submersible container. The first task here is to remove the odor. Above the container, three straws are facing the pouring opening. The straw will suck the odor emitted by the garbage into the deodorization device for treatment, and then discharge it after reaching the standard. At the same time, several washing machines specially set up at the site will also wash the tires of the unloaded vehicles to prevent the vehicles from taking out the muck.
After the swill enters the treatment equipment, the treatment equipment will crush the garbage bag and then adsorb heavy metals. The sorted swill will be poured into a huge metal swill bucket and transported to the next workshop by forklift. In this workshop, there are two rows of equipment like boilers. When swill is poured into the boiler, a kind of bacteria will be added. After 7-8 hours of "boiling", the swill will become minced meat. In another workshop, there are layers of pockets. It is filled with crushed corn husks, mixed with "meat floss" and bagged to become the final product-animal feed.
After the factory was officially put into operation in September 20 10, the daily processing capacity of kitchen waste can reach 200 tons. After the second phase of the project is started, the daily processing capacity will reach 400 tons. It can basically solve the problem of kitchen waste treatment for 4 million urban people, and directly reduce carbon dioxide emissions by at least 6.5438+0.5 million tons. The annual output of 80,000 tons of recycled products will drive 400,000 mu of green organic agriculture and cleaner production of more than 654.38 billion broilers every year, and drive agricultural carbon dioxide emission reduction by 750,000 tons.
This is a "fighter" for kitchen waste disposal. Some institutions and campus associations in Beijing. Small kitchen processors are also in operation, converting leftovers from canteens or families into fertilizers for greening and beautifying campuses and communities.
There is also a smaller "little guy". At the opening ceremony of 13 Beijing International Science and Technology Industry Expo, the domestic food waste disposer aroused great interest of the audience. This kind of processor is suitable for the kitchen of ordinary families. It is directly installed at the lower outlet of the kitchen sink, and the high-speed motor drives the crushing parts to crush leftovers, vegetable branches, chicken bones, fish bones, etc. into powder or tiny particles, which are naturally discharged into the sewer along with the water flow, so as to realize the classification and reduction of kitchen waste from the source and realize the centralized pollution-free treatment of resource waste.
More interestingly, ships have also begun to carry a new equipment-the garbage disposal device in the kitchen of the ship's restaurant. In the past, naval vessels were often troubled by kitchen waste, especially for long-distance training. The kitchen waste after each meal can only be piled up and treated when returning to the military port. This device is slightly wider than the vertical refrigerator and can be placed in any corner of the kitchen. After the kitchen waste is put in, it is crushed, dehydrated and dried, and the sewage is discharged into the bilge sewage pool. After microwave drying, disinfection and sterilization, the dried food becomes colorless and odorless powder, which can be stored for 3 months without special treatment. Take 30 kilograms of kitchen waste as an example. After treatment by this device, only about 2.5 kilograms of dry powder is left, which meets the needs of ship navigation and environmental protection requirements when visiting other countries. After crushing, dehydration and drying, a bag of powder the size of Nestle coffee is left in the 5 kg watermelon. At present, in addition to a new destroyer, this device has also been added, and this device has also been used on the "Snow Dragon" scientific research ship that is inspecting the Antarctic! (Author: Zhang)