Thread Content
These days, more companies are using pentane gas as a fuel. As a hazardous chemical, I’ve recently come across two design approaches that are completely different from each other; I’m quite puzzled by this. I’m raising this issue here in hopes of getting more opinions from everyone. Thank you! Let’s first introduce this gasification unit. Simply put, it vaporizes pentane and mixes it with air, which is then sent to the subsequent gas-using equipment. Since the boiling point of pentane is 36.1°C, this gives it certain special considerations during storage and use. ①Should a pentane storage tank be classified as a pressure vessel? According to the petrochemical regulations, “6.2.3 For storing Class A-B liquids with a boiling point below 45°C, pressure or low-pressure storage tanks should be used.” ” I found an enterprise standard online, QBT 2911-2007, titled \"Technical Specifications for the Safety of Household and Similar Electrical Appliances Produced Using Cyclopentane as a Foaming Agent,\" which states that pentane storage tanks should be classified as Category II pressure vessels. Considering the actual conditions, during the hot summer months, the outdoor temperature can reach 40–50°C. Given this, the pressure inside the pentane storage tank in such outdoor conditions is relatively high. But even at such temperatures, it is impossible for an entire tank with a volume of dozens of cubic meters to reach the ambient temperature. If shading and cooling spray measures are taken simultaneously, can it be ensured that the tank does not need to be treated as a pressure vessel? ②Can the vaporization unit be arranged adjacent to the pentane storage tank? For things like liquefied hydrocarbons, there are also many low-temperature liquid storage tanks, and the vaporizers are arranged adjacent to them; in such cases, we consider the vaporization units to be auxiliary facilities for the storage tanks. Due to the high requirements and significant risks associated with low-temperature liquid transmission pipelines, an adjacent layout is chosen for safety and economic reasons. So can the pentane vaporization units be arranged adjacent to each other? In my personal view, although it is called a vaporization unit, it is not actually an auxiliary facility attached to the storage tank, but rather an auxiliary facility for the production workshop. From safety and economic perspectives, pipelines for transporting liquid pentane are certainly safer than those for transporting a mixture of pentane gas and air; the requirements regarding pipeline material and connection methods are also lower. Therefore, it is more reasonable to locate this vaporization unit near the workshop where it will be used. Due to the requirements regarding the fire separation distance between flammable liquid storage tanks and workshops, it is necessary to consider whether the gasification unit should be located close to the storage tanks or close to the workshops. Of the two design options I’m seeing now, one considers the gasification unit as a building with fire resistance ratings of level 1 or 2, requiring a fire separation distance of 12 meters from the storage tanks (for tanks with a capacity of less than 50 m3) ； Another approach is to consider installing firebreaks. I think the placement of the fire dike is unreasonable. I’m seeking everyone’s advice – how do you think it should be considered?