liquid ring vacuum pump of vacuum packing
Vacuum packing of liquid ring vacuum pump is a kind of packing method, in which articles are put into airtight containers and vacuum pumping system is used before sealing, so that there is no air in sealed containers at all. This kind of packaging can prevent the moisture from entering the packaging container, and also avoid the moisture in the sealed moisture-proof packaging and dew when the temperature drops.
Vacuum packing method is used for liquid ring vacuum pump, and attention should be paid to prevent excessive vacuum. Common grains and processed goods can be packed in vacuum. Vacuum packaging can not only prevent or reduce the oxidation, discoloration and taste of grains, but also inhibit the growth of some fungi and bacteria.
In addition to controlling external temperature and sterility, the vacuum packaging of water ring vacuum pump is more important to control the suitable gas environment of grain to achieve the desired fresh-keeping purpose. The main methods are mechanical extrusion type and suction tube degassing type. In any way, the liquid ring vacuum pump is to extract the air from the packaging bag and then heat seal it. Its main characteristics are: reducing oxygen content in bags, inhibiting the growth and development of fungi and bacteria, controlling grain metamorphosis, and achieving the purpose of preservation and quality. In addition, after vacuum packaging, it can also resist mechanical pressure and reduce vibration, which is conducive to long-distance transportation and sales. The main function of vacuum filling packaging with liquid ring vacuum pump is not only the function of oxygen and quality preservation, but also the function of pressure resistance, gas blocking and fresh keeping. It can make food stick to its original color, aroma, taste, shape and nutritional value for a long time.
In addition, there are many foods that are not suitable for vacuum packaging and must be packed with vacuum inflation. For example, crunchy and fragile food, caking food, deformable and oily food, food with sharp edges or high hardness will puncture the packaging bags, etc. After food is packed by vacuum aeration, the air pressure inside the bag is stronger than that outside the bag. It can effectively avoid food crushing and deformation without affecting the appearance of the bag and printing decoration. Vacuum air-filled packaging is then filled with nitrogen, carbon dioxide, oxygen single gas or two or three gases of mixed gas liquid ring vacuum pump.
Nitrogen is inert gas, which fills the bag and keeps the positive pressure inside, so as to avoid the air outside the bag entering the bag and play a maintenance role for food. Its carbon dioxide can dissolve in various kinds of fat or water, lead to weak acidity of carbonate, has the activity of inhibiting microorganisms such as fungi, erosion bacteria and so on. Its oxygen can inhibit the growth and reproduction of anaerobic bacteria, adhere to the novelty and color of fruits and vegetables, and high concentration of oxygen can make new. Under its working pressure, the liquid ring vacuum pump should be able to discharge all the gas produced in the process of vacuum equipment. Understand the composition of the exhausted gas, the gas contains no condensable vapor, particle dust, corrosion and so on. When choosing a vacuum pump, it is necessary to know the gas composition and select the appropriate pump for the pumped gas.
If the gas contains vapor, particles, and corrosive gases, it should be considered to install auxiliary equipment such as condenser, dust collector in the intake pipeline of the pump. How does the oil vapor discharged from the liquid ring vacuum pump affect the environment? If the environment is not allowed to be polluted, oil-free vacuum pumps can be selected, or oil vapor can be discharged outdoors. Whether the vibration caused by the operation of liquid ring vacuum pump has an impact on the process and environment. If the process is not allowed, vibration-free pumps should be selected or anti-vibration measures should be taken. Vacuum pump price, operation and maintenance costs.
Requirements for oil contamination in vacuum equipment. If the equipment is strictly oil-free, all kinds of oil-free pumps should be selected. If the requirements are not strict, you can choose to have oil pumps, plus some anti-oil pollution measures, such as adding cold traps, baffles, oil traps, etc., can also meet the requirements of clean vacuum.