DEAR Air separation equipment.When the liquid level increases, the flow velocity in the oxygen channel increases and the bubbles on the wall are continuously washed, which will improve the heat transfer coefficient of the evaporation side. For the heat transfer on the condensation side, the heat transfer coefficient is larger than that on the evaporation side, and the heat transfer coefficient is almost constant when the height of the plate unit is determined.The convective heat transfer process of heat transfer from wall 2 to cold fluid (temperature is TF2). The process of heat transfer in inter wall heat exchanger is generally composed of three stages: convection heat conduction convection. For example, in a plate fin heat exchanger, the air first transfers heat to the fins and baffles, and then to the backflow gas to reheat oxygen, pure nitrogen and dirty nitrogen, and the air temperature decreases due to heat release.DEAR Air separation equipment.Medium pressure blow off: after high pressure blow off, close the main inlet valve of high pressure air and open the blow off valve of oil-water separator. Install high pressure and medium pressure gauges, install and close throttle-1 valve. Close the blow-1 and blow-2 valves, then open the main inlet valve of high pressure air and close the blow off valve.
DEAR Air separation equipment.When blowing out the oil and water at all levels of the air compressor, we can see that there is always a large amount of water blowing out from the separator. Where does the water come from? This is because the amount of water that can be contained in every cubic meter of air mainly depends on the temperature, but has little to do with the total air pressure. For example, at 30 ℃ and 0.1MPa pressure, the saturated moisture content in the air is 30.3g/m3.The overall temperature difference in the tower is less than 60 ℃ in the hot state and more than 200 ℃ in the cold state. In order to prevent the damage caused by the excessive thermal stress of the tower internals and pipes, there is a difference in the operation procedure between the full heating under the cold state and the full heating under the hot state.The adjustment of temperature condition is usually based on the middle temperature. The ratio of backflow and positive flow can be changed by changing the middle extraction volume (or ring flow), product oxygen or nitrogen flow and air flow, so as to control the temperature difference between hot end and cold end within the allowable range.
DEAR Air separation equipment.Oxygen is the material on which all living organisms on the earth rely for survival. It is easy to react with other substances to form oxides, which will generate a lot of heat in the oxidation process. Therefore, as an oxidant and combustion supporting agent, oxygen is widely used in metallurgy, chemical industry, energy, machinery, national defense industry and other sectors.In the process of all low pressure switching air separation plant, a bypass valve is usually installed on the pipeline between the air leaving the switching heat exchanger and the sewage nitrogen entering the switching heat exchanger, which plays a very important role in the start-up stage: a part of the cooled air can return to the switching heat exchanger through the bypass valve to release the cooling capacity.Machinery industry, mainly used for metal cutting and welding. Oxygen is used as combustion supporting agent of acetylene to produce high temperature flame and melt metal. In national defense industry, liquid oxygen is often used as the combustion supporting agent of rocket. The combustible material soaked in liquid oxygen has strong explosiveness and can be used to make liquid oxygen explosive. In addition, in the medical sector, oxygen is also an indispensable material for first aid and adjuvant treatment of patients. Therefore, oxygen production is an indispensable part of the national economy.
