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With the improvement of people's living standards in my country and the improvement of urban infrastructure, bottled liquefied petroleum gas is used more and more widely, including residential buildings, restaurants, factories, gas central air conditioners, etc. The gas consumption is increasing, so there are more and more liquefied petroleum gas storage tank stations. Due to professional reasons, I participated in the design review, construction, and operation management inspection of about 50 liquefied petroleum gas storage tank stations and gasification stations in Nanhai, Foshan, Shunde, Zhuhai, Shaoguan and other places. I analyzed common problems in the design and construction of liquefied petroleum gas stations in the southern region and provided solutions. 1. There is no gas-liquid separator installed at the air inlet of the liquefied petroleum gas compressor. According to Article 6.3.28 of the "Urban Gas Design Code" (CB50028-93) (hereinafter referred to as the specification) "The inlet of the liquefied petroleum gas compressor should be equipped with a gas-liquid separator, and the outlet should be equipped with an oil-gas separator. ”However, most of the liquefied petroleum gas stations in the south do not have a gas-liquid separator in front of the compressor. However, because most of the gas pipelines in the gas stations are not insulated and exposed to the atmosphere, when the power of the compressor is relatively large or the weather is cold, the gas pipelines The liquefied petroleum gas of China Re Liquefied Petroleum enters the compressor along with the air flow. Although some domestic and imported compressors are equipped with small-volume gas-liquid separators at the air inlet, this will also cause the LPG compressor to automatically and often be forced to shut down, and even lead to compressor damage accidents, seriously affecting production safety. However, after some gas stations install a gas-liquid separator larger than 1m3 in front of the compressor inlet, practice has proven that the compressor operates very smoothly and basically does not stop. 2. Anti-vibration rubber hoses are not installed on the inlet and outlet pipelines of the liquefied petroleum gas pump. According to Article 6.3.21 of the "Urban Gas Design Code", "The inlet and outlet of the liquid liquefied petroleum gas pump should be equipped with high-pressure oil-resistant armored rubber pipes with a length of about 0.5 meters or other measures to prevent vibration." ”However, it was found that the oil and gas pumps in the liquefaction plants of most gas stations were not equipped with anti-vibration hoses. Instead, common pipe codes were used to fix the pump inlet and outlet pipelines on the pipe racks. Therefore, the pipeline connected to the LPG pump vibrates with the pulsation of the pump. Some gas stations cause cavitation due to the pump inlet pipe being too long or poor installation technology. Even the pressure gauge on the pipeline connected to the pump is often vibrated, which brings great hidden dangers to safe production and operation. However, the liquefied petroleum gas pump with the anti-vibration hose correctly installed in accordance with the specification requirements runs smoothly without frequent damage to the pressure gauge. So I think: High-pressure resistant and anti-vibration hoses should be installed at the inlet and outlet of the LPG pump in strict accordance with the regulations. 3. The spray device of the liquefied petroleum gas storage tank adopts the drilling method on the annular fire pipe. According to Article 6.9.1 of the "Urban Gas Design Code" "... the liquefied petroleum gas storage tank should be equipped with a fixed spray device. The water supply intensity of the sprinkler device should not be less than 0.15L/S. m2. ”I found that many gas stations use fixed spray devices for LPG storage tanks to drill holes directly into the annular fire pipeline. Although the spray intensity of the newly completed LPG station is basically satisfactory, the atomization effect can only be barely satisfactory. However, when the LPG station has been running for a period of time, the inclination and diameter of the water holes will change due to corrosion of the drilled holes. The spray intensity and atomization effect cannot meet the requirements of the specification, and will * * Reduce fire protection system water pressure. For fixed sprinkler devices that use atomizing sprinkler heads, except that some sprinklers may be clogged, the spray intensity, atomization effect, and fire protection system water pressure can basically meet the requirements and specifications. Moreover, the problem of sprinkler plugging can be solved through improvements in process installation and design. so i think: The fixed spray device of the LPG storage tank should insist on using the spray nozzle method, and cannot use the method of drilling holes directly on the annular fire pipe due to the convenience of construction and to reduce investment costs. 4. Use fish ponds, ponds, and gushing water from rivers for fire-fighting water. I found that many liquefied petroleum gas tank stations in the south use fish ponds, ponds, and gushing water from small rivers as water sources, and some of them are smelly dirty water. Although the relevant standards do not have strict regulations on the quality of fire-fighting water, from the actual use effect, it has seriously affected the fire-fighting water. Because water sources such as fish ponds, water ponds, and small streams are rich in silt, floating plants, and organic matter. Although fire water intake pipes are generally filtered by grilles, filter valves, etc., in fact, once the fire pump pumps water, the grilles and filter valves of the water intake will accumulate a large amount of silt and floating plants on the water surface, which greatly reduces the amount of fire water intake and seriously affects the fire water. Moreover, since water contains a large amount of dirt and organic matter, when conducting fire drills * Or when cooling and spraying, impurities in the water will intensify the corrosion of pipes, valves, and storage tanks and block the nozzles. Serious corrosion will greatly increase maintenance costs. Therefore, for the fire-fighting water of flammable and explosive LPG storage tanks, the fire pool design should be considered during construction. Although it increases the one-time investment, it improves the fire-fighting reliability and spraying effect of the LPG storage tank station, and enhances the ability to prevent and eliminate accidents in the initial stage of the accident. 5 The operating platform surface of the storage tank area is made of patterned steel plates. In most LPG tank stations, the operating platform floors of the storage tank areas are generally laid with patterned steel plates. Although they are generally treated with simple anti-corrosion paint, the patterned steel plates are prone to water accumulation and production personnel often Because it is walked on, a large area of rust will appear after a period of use, and it is difficult to repair. At the same time, the rust on the platform will cause the appearance of the storage tank to be full of rust. After a long time, the patterned steel plate will be severely corroded, which may lead to industrial accidents for workers who go to the platform for maintenance. Therefore, I think that the operating platform surface of the tank area should not be laid with patterned steel plates, but should consider using galvanized anti-skid steel plates with leakage holes or galvanized steel grilles and other materials. 6. The safety valves on compressors, pumps and outlet pipelines do not use pipelines to lead the relief ports to high places. It is found that the relief ports of the safety valves on compressors, pumps and pipelines of many gas stations do not use pipelines to lead to high places. It may be thought that when the safety valve takes off, it does not matter if the gas is released. However, in some gas stations, due to misoperation by operators, the pipelines on the compressor and behind the pump jumped due to overpressure. The high-speed jetting of gas and liquid had an astonishing impact and was accompanied by a scream. Fortunately, no one was injured standing at the safety valve relief port. However, the brick wall about 1 meter away from the safety valve relief port still left traces of strong impact. Therefore, in order to protect the personal safety of the operators, special pipelines for the safety valve relief port were led to outdoor high places or high places. 7. Serious corrosion at the contact point between the LPG pipeline and the pipe frame. In LPG tank stations, corrosion is common at the contact point between the LPG pipeline and the pipe frame. It is difficult to remove rust, repair and prevent corrosion at the contact area, and it is also difficult to detect the degree of corrosion. Rainwater is easy to accumulate and the humidity is high. However, the construction quality of individual gas stations is relatively poor, and the rust situation is more serious. In just four years after completion, there were serious consequences of perforations and air leaks between the secondary pipeline and the pipe frame. So I think: First, regular maintenance and inspections should be strengthened, and repairs and anti-corrosion should be done carefully. Second, during the preparation and construction process, a steel plate of the same diameter can be welded to the pipeline contact part to increase the thickness of corrosion resistance. 8 The design of the safety valve vent pipe on the storage tank is simple. The vent pipe of the safety valve of many LPG tank stations is very simple - the vent pipe mouth points directly to the sky. According to paragraph 3 of Article 6.7.11 of the specification, "the pipe mouth is more than 2m above the tank platform". However, this will bring about two serious problems: (1) A large amount of rainwater accumulates at the outlet of the safety valve, and the current acid rain situation is relatively serious (more than 70% of Foshan area is acid rain), so the accumulated rainwater is generally acidic, and the PH value is generally greater than 5, causing serious rust inside the safety valve, and even causing the safety valve to be scrapped when sent for pick-up. ； (2) Some birds build nests in the release pipe, and dead leaves, branches and other debris used for nesting accumulate in the release port of the safety valve, making it difficult or even impossible for the safety valve to take off, posing a safety hazard. In order to avoid the problem of rainwater intrusion, some gas stations add a -90° elbow to the outlet of the safety valve relief port, pointing in the horizontal direction. I think this will cause the emergency relief to not be fully diffused in time, especially if a tank is on fire during an accident. Based on some good experience, I believe that the nozzle of the dispersion pipe should point toward the sky, but the nozzle should also be equipped with measures to prevent rain and flying crows, such as putting a lightweight (such as aluminum) tube on the nozzle that is slightly larger than the diameter of the nozzle. This post was last edited by zhangyong6404 on 2009-3-14 14:57 ]