Hello everyone, I would like to ask whether a dichloromethane storage tank requires a nitrogen blanket

https://bbs.hcbbs.com/thread-3224711-1-1.html

Cooling measures, vapor prevention measures!

Let me share a somewhat immature idea: it would be possible to develop a vaporization and pressure stabilization system for dichloromethane. The storage tank could be designed as a horizontal pressure vessel that stores the liquid at a pressure slightly above atmospheric level. When the pressure drops due to discharge or cooling, the stabilization system uses control valves to replenish the pressure; the tank is capable of withstanding higher pressures as well. By doing this, no nitrogen needs to be used, resulting in virtually zero emissions. The energy required for insulating and heating the storage tank is minimal, and a capacity of a few hundred liters should be sufficient.

I’m feeling good too. Will the costs increase? The property owner should find ways to save money, right?:lol

The operating costs are usually lower than those of nitrogen sealing and refrigerant cooling, while the installation costs are higher; the key aspect is environmental protection.

What was seen were all vertical stainless steel storage tanks, designed for shading and cooling

The normal boiling point of dichloromethane is 39.8°C, and its saturated vapor pressures at 0/20/40 and 50°C are 19/47/102/144 kPa respectively. At room temperature, the density of the liquid is approximately 1.3 to 1.35 times that of water. According to the Petrochemical Regulations, it is classified as a Class C material in terms of fire hazard. For storage tanks with a volume of 100 cubic meters or less, they are usually designed as tower-type vertical tanks with a relatively large height-to-diameter ratio, and the design pressure takes into account resistance to low pressures and vacuum. During normal operation, as long as there is a liquid level of a few meters high at the bottom, the negative pressure at the top of the pipe will not cause difficulties in pumping the fluid out. In cold winter regions, it is generally necessary to consider heat tracing for the storage tank, so as to prevent difficulties in pump discharge caused by a significant drop in vacuum at low temperatures. For storage tanks with a volume of several hundred cubic meters, the approach used in Building 4 is also quite good. Larger-volume dichloromethane storage tanks generally need to be designed as low-pressure tanks, equipped with a nitrogen blanketing system and a reliable treatment system for hydrocarbon chloride-containing exhaust gases, such as water absorption after combustion (to recover ~20% hydrochloric acid) and alkaline washing.

I can handle the dichloromethane recovery process for tank farms; feel free to contact me if you need it