After the accumulator runs for a period of time, due to the impact of air flow back and forth, the filled pebbles will gradually be compacted and sink. In addition, the amount of pebbles will be insufficient due to the abrasion or breakage of pebbles. If the pebble is not filled tightly, the air will drive the pebble to jump up and down, which is easy to damage the coil, which can be judged from the sound of hitting the pipe wall. The lack of pebbles also affects the heat storage capacity. Therefore, it is necessary to supplement in time.DEAR Air separation equipment.In the start-up operation, attention must be paid to gradually reduce the temperature difference at the hot end of the cold accumulator or the switching heat exchanger; before accumulating enough liquid, do not rush to start the liquid oxygen pump or deliver oxygen. If the cooling loss is limited to a minimum, more cooling capacity can be used to liquefy the gas and the start-up time can be shortened.When the group with small flow is moving air, the pressure of the main air pipe rises and the temperature in the middle part is low, which indicates that some automatic air valves are not opened. When some of the automatic valves are not opened, the pressure of the upper tower will rise and the temperature in the middle will be higher.
DEAR Air separation equipment.The liquid oxygen circulating adsorber is used to absorb the impurities in the liquid oxygen and switch regularly; if the acetylene or hydrocarbon content in the liquid oxygen exceeds the standard, the alarm will start. In addition to the requirement of discharging liquid oxygen equivalent to 1% of the gas oxygen output per hour, the liquid discharge shall be increased; the plate type main cooler shall adopt full immersion operation; the main cooler shall have good grounding device.DEAR Air separation equipment.In the switching heat exchanger, the positive and backward gas flow through different channels at the same time to exchange heat directly. Therefore, under normal conditions, it is basically a stable heat transfer process, that is, the temperature of each section of the heat exchanger (the temperature of positive flow and backflow gas, as well as the temperature of baffles and fins) does not change with time.The heat transfer of the fin is transferred to the cold fluid gradually from the root to the upper part of the fin. If there is a certain temperature drop inside the fin, the effect of the fin will be reduced, that is, the efficiency of the fin will be lower. Therefore, in order to effectively play the role of fins, so that it has a higher fin efficiency, in the case of large surface heat transfer coefficient, such as liquid channel, select short and thick fins.
DEAR Air separation equipment.For the liquid oxygen pump, the liquid oxygen at its inlet should be in the supercooled state, because if part of the liquid oxygen is gasified in the pump, the capacity of the pump will be reduced, and the liquid oxygen can not be smoothly transported to the main cooler. When the pressure of the upper tower drops too much, the temperature of the liquid oxygen at the inlet of the liquid oxygen pump will exceed the saturation temperature corresponding to the pressure, resulting in the gasification of part of the liquid oxygen and the "entrainment" phenomenon, so that the liquid oxygen can not be sent out, resulting in the rise of the liquid level at the bottom of the upper tower.Failure on the stem. The common fault is that the screw thread on the valve stem and screw sleeve is worn, which makes the valve unable to close. Generally, the screw thread of the valve stem is not easy to be worn, while the female thread on the screw sleeve (brass) is easy to be damaged. Most of the reasons are too much force when the valve is opened, or hard screw after the valve is opened or closed, so that the screw thread is damaged.
DEAR Air separation equipment.In the cold section of the switching heat exchanger, carbon dioxide has been basically removed theoretically, but due to the entrainment effect of the gas flow, the amount of carbon dioxide brought into the tower is much more than the theoretical content. In addition to being partially removed by the adsorption filter, the rest of the carbon dioxide will gradually accumulate in the tower and block the tray, pipes and valves.DEAR Air separation equipment.In energy industry, in order to maintain the temperature of oxidation layer in the furnace, enough oxygen must be supplied during coal pressurized gasification. The purity of oxygen is not less than 95%, and the oxygen consumption per kilogram of coal varies with the type and quality of coal. It is 0.14-0.18m3/kg for lignite and 0.17-0.22m3/kg for bituminous coal. The oxygen pressure is determined by the production process requirements. The higher the pressure, the less oxygen consumption. For the IGCC unit, the oxygen demand of 1kW is about 5.6m.
