May I ask whether storage tanks for flammable and explosive substances such as dichloromethane, dichloroethyl chloride, and benzene can have flat bottoms and roofs?

Based on intuitive judgment, dichloromethane is classified as a Category B chemical, while dichloroethane and benzene are classified as Category C chemicals. Benzene is a toxic substance; it can be stored in vertical atmospheric-pressure storage tanks, as well as in storage tanks with flat bottoms, arch-shaped or elliptical tops, or conical tops. To determine which type of storage tank to use, first identify the category of the chemical; based on its category and saturated vapor pressure, decide whether storage at atmospheric pressure or under pressure is appropriate.

With this flat-bottomed, cone-shaped design, it’s impossible to ensure proper welding; leaks are likely to occur. Can’t such materials be used for flammable and explosive hazardous substances? Is there such a saying?

All the storage tanks I’ve seen are vertical, flat-roofed carbon steel or stainless steel tanks. The safety assessment has been passed. Shouguang, Shandong

What type of medium do you store? How much pressure is there?

I’ve never seen this positive version

No pressure, chlorobenzene, dichloromethane, hydrogen peroxide, methanol, chloroprene,

This claim has no basis; the fabrication of storage tanks follows strict welding procedures and quality management systems, with all welds undergoing inspection and testing.

If you need an emergency shut-off valve, feel free to contact me

The claim that welding techniques are not suitable for storing flammable and explosive liquids seems unfounded; the manufacturing of storage tanks follows strict welding procedures and quality management systems, and welding work is subject to inspection and testing, so this should be under control. What affects the type of tanks used for storing flammable and explosive liquids are likely the storage conditions ； According to current regulatory requirements, storage tanks for Class A and B liquids must be sealed with nitrogen, which means they need to be maintained at a slight positive pressure. Under such conditions, flat-bottom and flat-roof designs, as well as flat-bottom cone-roof designs, are not suitable, as these types are not permitted to have any pressure. Therefore, flat-bottom arch roofs, or vertical double-elliptical heads or horizontal double-elliptical heads are generally used. For Class A liquids or Class B liquids stored under pressure, vertical double-elliptical head, horizontal double-elliptical head, or spherical tanks are the only options available.