Dear users, if you want to build a suitable cold storage, Dehe (Beijing) Artificial Environment Technology Co., Ltd. suggests that you consider the following aspects:
1. Determine the size (length× width× height) of the cold storage according to the tonnage of the goods stored by yourself, the daily incoming shipments and the size of the building, and determine the specifications and dimensions of the warehouse door. The opening direction of the door should be clean, dry and ventilated.
2. According to the stored articles, select and determine the temperature in the warehouse for fresh storage:+5-5℃, refrigeration and freezing: -18℃, and low temperature storage:-18-3℃).
3. according to the characteristics of your own building and the local water source, choose the refrigeration mode of the refrigerator, which generally includes air cooling and water cooling. (Users who are air-cooled refrigerators only need to choose the installation location, and users who are water-cooled refrigerators also need to configure the installation locations of pools or deep wells, circulating water pipes, pumps and cooling towers).
1. What is fresh-keeping storage in cold storage
Storage or fresh-keeping storage, its main content is fresh-keeping, that is, maintaining the original quality and freshness of some agricultural products to the maximum extent for a long time, that is, fresh agricultural products, after fresh-keeping storage for a period of time, are still fresh and fresh when they are just picked or close to them.
2. Relationship between temperature and fresh-keeping storage of agricultural products
Agricultural products are still a living body after harvest. In order to maintain their life during storage, they must consume their own storage nutrition, thus gradually losing their nutritional value and fresh quality. In addition, pests will also regard the stored nutrition of agricultural products as food, which will lead to the deterioration of agricultural products and the loss of freshness and edible value. Temperature is the most important factor to keep the nutrition and fresh quality of postharvest agricultural products alive. Generally speaking, the lower the temperature, the less the nutritional consumption of products, the worse the damage caused by pests and diseases, and the longer the time to maintain fresh quality. At the same time, the smaller the temperature change, the better the preservation effect. The fresh-keeping temperature is not infinitely low, because when the temperature is so low that the product can't stand it, cold damage or freezing damage will also occur. Therefore, fresh-keeping storage requires a relatively stable and suitable low temperature condition. The optimum fresh-keeping temperature of most agricultural products is about ℃.
3. The optimum temperature for maintaining fresh-keeping storage of agricultural products
The temperature is constantly changing with the season of the year and the time of the day. In most agricultural products, the temperature is high in the season of conventional cultivation and harvesting, and the temperature varies greatly from day to night, which is extremely unsuitable for fresh-keeping storage of products. Many simple methods are to find a stable place with low natural temperature to store agricultural products, such as caves, earth pits, shady places, etc. These methods can not control the temperature at will, and the preservation effect is poor and the preservation period is relatively short. In order to meet the requirements of long-term preservation and storage of products, the ultimate solution is to artificially create a relatively stable low-temperature condition, that is, through mechanical equipment and electronic instruments, the temperature can be artificially controlled within a certain range. Common cold storage is such a facility.
4. what is a cold storage
a cold storage generally refers to a facility that uses various equipment for refrigeration, can be artificially controlled and keeps a stable low temperature. Its basic components are: refrigeration system; Electric control device; A warehouse with certain thermal insulation performance; Attached buildings, etc.
the refrigeration system mainly includes all kinds of refrigeration equipment. The refrigeration equipment is the heart of the cold storage, which produces cold energy and ensures the supply of cold sources in the warehouse. The electric control device is the brain of the cold storage, which directs the refrigeration system to ensure the cold supply.
A warehouse with certain heat insulation performance is a place for storing fresh-keeping agricultural products. Its function is to keep the low-temperature environment stable. Usually, the heat insulation performance is called heat preservation. The good thermal insulation structure of the warehouse can keep the cold produced by refrigeration equipment from leaking to the outside as much as possible, on the other hand, it is to minimize the leakage of heat from outside the warehouse to the inside, which is also the main difference between a cold storage and a general house.
5. Selection and construction of cold storage types and rural production areas
There are many types of cold storage in China, and there is no unified standard for classification. According to the types commonly used in producing areas, it is briefly introduced as follows:
(1) According to the storage capacity, there are large, medium and small types. Generally speaking, commercial large and medium-sized libraries have large storage capacity. According to the characteristics that the cold storage in our country is relatively small at present and the customary appellation of the masses, the warehouses with a storage capacity of more than 1 tons can be called large warehouses, the warehouses with a storage capacity of less than 1 tons and more than 1 tons can be called medium warehouses, and the warehouses with a storage capacity of less than 1 tons can be called small warehouses. The country of origin is most suitable for building a small cold storage of 1 tons to 1 tons.
(2) According to the refrigerant used in the refrigerator, it can be divided into ammonia hangar with ammonia mechanism cooling and fluorine hangar with fluorine mechanism cooling, and fluorine hangar with high automation can be used to build small cold storage in rural areas.
(3) According to the temperature of the cold storage, there are low-temperature storage and high-temperature storage, and the fresh-keeping storage of fruits and vegetables is generally high-temperature, with the lowest temperature of-2℃. Fresh-keeping warehouses for aquatic products and meat products are low-temperature warehouses with the temperature below-18℃.
(4) according to the form of cold distributor in cold storage, there are cold storage with exhaust pipes and cold air blowers. The fresh-keeping of fruits and vegetables generally uses a cold air blower cold storage, commonly known as a cold air storage.
(5) according to the building mode of the warehouse, it is divided into civil cold storage, assembled cold storage and civil assembled composite cold storage. Civil cold storage is generally a sandwich wall insulation structure, which occupies a large area and has a long construction period. Early cold storage is this way. Assembled cold storage is a prefabricated warehouse with prefabricated insulation boards. Its construction period is short and it can be disassembled, but its investment is large. Civil engineering assembly compound cold storage, the load-bearing and peripheral structure of the warehouse is in the form of civil engineering, and the thermal insulation structure is in the form of polyurethane spray foaming or polystyrene foam board assembly. Among them, the civil assembly compound cold storage with polystyrene foam board insulation is the most economical and applicable, and it is the first choice for building cold storage in the producing area.
6. Refrigeration equipment suitable for small cold storage
Refrigeration equipment of cold storage is the heart of cold storage, which is very important. The most critical condition for a cold storage is refrigeration equipment. The main body of refrigeration equipment is refrigerator, which has many kinds, including ammonia machine and fluorine machine according to refrigerant. While some fluorine machines are common models for many refrigerants, advanced fluorine machines mostly use R22 and other new refrigerants with little impact on the environment. Fluorine machine is generally small in size, low in noise, safe and reliable, high in automation and wide in application, and is suitable for small rural cold storage. The combination of refrigerator and condenser is often called refrigeration unit, which can be divided into water cooling unit and air cooling unit. Air-cooled units are the preferred form of small cold storage, which has the advantages of simplicity, compactness, easy installation, convenient operation and few ancillary equipment. The refrigerator of refrigeration unit is the heart of refrigeration equipment. Common compression refrigerators can be divided into open, semi-closed and fully closed types. The fully enclosed compressor has the advantages of small volume, low noise, low power consumption, high efficiency and energy saving. It is the first choice for small rural cold storage. The air-cooled refrigeration unit, which is mainly composed of fully enclosed compressors, can be made into a form like split air conditioner and hung on the wall. At present, the better fully enclosed refrigeration compressors on the market are reliable in quality, but the price is more than 5% higher than that of domestic ones.
7. Advantages of building a small cold storage in rural areas It is most suitable to build a small cold storage of 1-2 tons in rural areas. The investment in small cold storage is about 2,-4, yuan, which is acceptable to ordinary farmers. This small cold storage unit has the advantages of small capacity, easy control, convenient entry and exit, easy storage of a product, rapid cooling, stable temperature, low power consumption and high degree of automation, which is as easy to manage as household air conditioners and refrigerators. A number of these small cold storages are built together to form a small cold storage group, with a total capacity of hundreds of tons and thousands of tons, and its total investment is similar to that of medium and large cold storages of the same scale. However, it can preserve more products and varieties, and can be controlled at will according to its different preservation temperature requirements, which is not easy for large-capacity cold storage. In short, the flexibility, operability, automation, energy-saving effect and management effect of small cold storage groups are much better than those of medium and large cold storage groups.
8. Recommend several modern small cold storages to everyone
(1) Civil assembly compound small cold air storage The civil assembly compound small cold air storage is a new type of cold storage developed and built in shandong institute of pomology. Its wall and roof are brick-wood, brick-tile or brick-concrete structure, and the thermal insulation structure is to apply thermal insulation materials on the inner wall of civil buildings. The storage capacity is less than 1 tons, and the representative storage types are TZFX－1Q and TZFX－2Q. Build a standard TZFX－1Q civil assembly compound small cold air warehouse with a design capacity of 1 tons and a volume of 6 cubic meters. The economic thermal insulation project with polystyrene insulation board as the main part is about 7, yuan, and the refrigeration project is about 2, yuan. The whole project includes construction cost and installation cost, and it is less than 27, yuan to deliver a normal warehouse. A 2-ton TZFX－2Q civil assembly compound small cold air storage is about 11 cubic meters, with an economic insulation project of more than 1, yuan, a refrigeration project of less than 3, yuan, and a total project cost of about 4, yuan. The above-mentioned 1-ton and 2-ton warehouses do not include the civil part of the house. The civil house is a general private house with no windows and only a doorway. The 1-ton warehouse is a larger house, and the 2-ton warehouse is two houses. The standards and costs of new houses vary from place to place. The construction cost of the houses required here is lower than that of the houses inhabited by people, because they are informal and do not need decoration, as long as they are firm and reliable. The cost of thermal insulation project sprayed with polyurethane is more than 4% higher than that of polystyrene board. TZFX series civil assembled small cold air storage, equipped with FGWQ series hanging machine, 1 tons equipped with FGWQ－31 or 32; 2-ton configuration FGWQ－51 or 52. High efficiency, low noise and fully automatic operation.
(2)TZTZ series automatic cold storage for bobbin houses is another new type of cold storage developed in shandong institute of pomology, which is a multi-machine cold storage with a single room capacity of more than 5 tons. The building form of TZTZ series automatic cold storage with bobbin houses is 3-4 meters wide and 2 meters long, with one door at each end or more than two doors at one side. The simple and economical building is in the form of 24 brick walls and floor roofs. The warehouse can block windows and redundant doors, and it can also be transformed into an automatic cold storage in a bobbin house. Like TZFX series cold storage, the thermal insulation structure of automatic cold storage in bobbin house can adopt the economic form of multi-layer polystyrene foam board composite assembly. The refrigeration equipment of automatic cold storage in bobbin house is FGWQ series hanging machine, which does not need special machine room. A plurality of hanging machines and electric control boxes are hung on one side of the warehouse. Each hanging machine and the air cooler in the warehouse are independent systems. By setting the number of hanging machine workstations, the power consumption can be easily adjusted. For example, when centralized storage, all the hanging machines are put into work to quickly cool down; In the maintenance stage of reservoir temperature and low temperature season, you can choose to put some of them into work, so as to reduce power consumption and operating costs. The automatic cold storage of bobbin house can be used as a pre-cooling workshop to quickly cool products, with one end receiving goods and the other end delivering them, thus realizing assembly line operation. Together, otherwise, the watermelon will soften early and shorten the fresh-keeping time.