Key design considerations and safety requirements for methanol storage tanks and tank areas
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I need to carry out the design of a methanol storage tank and its associated area in the near future; I would appreciate it if experts could advise me on the key design aspects as well as the relevant safety requirements.
Experience from our unit: The methanol tank area should be located at a distance from the production units; it should be surrounded by a wall one meter high, with water channels installed at the bottom. Each tank must be equipped with spray cooling water systems, which requires the construction of corresponding pipelines, underground water channels, and manholes. Next to the tank area, there must be a pump room to facilitate pumping methanol back to the plant area. Fire monitors should be installed around the tank area, along with a certain number of fire extinguishers and other equipment
This should be discussed within the context of process design, as it relates primarily to safety aspects. There are specific standards and regulations for the design of storage tanks, such as the design specifications for fire protection in petrochemical enterprises. What was said on the second floor has some issues: a wall one meter high is not appropriate; instead, a fire dike should be used, and there are corresponding standards for that as well. The waterway setup is also incorrect; a water seal well should be installed, along with a foam fire extinguishing system. Generally, methanol pumps do not have dedicated pump rooms, mainly due to considerations such as the volatility of methanol
If you set it so high, how can the staff on duty enter to carry out inspections? In the event of a fire, they won’t even dare to go there immediately. The fences in our area are mainly meant to facilitate access for people; we can’t focus solely on safety – we need to consider practical realities. If you don’t install a pump room, how can the methanol in the irrigation area be sent back to the distillation tower? These mainly refer to the design concepts of the five-ring system
Thank you very much for the generous guidance from the 2nd, 3rd, and 4th floors! ! !
In accordance with building code requirements, a fire dike at least 1.1 meters high should be constructed around the methanol storage tanks, along with fire-resistant steps to facilitate access for personnel
1. The methanol tank area is equipped with fire dikes, pipe supports, etc., all made of non-combustible materials. Install a steam safety system, fixed water spray cooling equipment, and a vent-fire arrestor system. The storage tank is equipped with an electrostatic grounding system, a fixed water spray cooling system, and a vent-regulator system. 2. Flammable gas detection and alarm devices shall be installed in the methanol tank area. 3. Design fire protection facilities in accordance with **relevant regulatory requirements, including the installation of indoor and outdoor fire hydrants as well as mobile firefighting equipment. 4. Fixed foam fire extinguishing stations and water spray cooling facilities are installed in the tank area. 5. The fire pump room in the storage tank area is powered by two power sources, uses cables made of fire-resistant materials for wiring, and is equipped with emergency lighting. 6. The factory site is equipped with a fire alarm system, and the fire control room contains an automatic fire alarm controller for receiving signals from the alarm system. The automatic fire alarm controller can receive fire alarm signals from combustible gas detectors, as well as activation signals from manual alarm buttons and fire hydrant buttons. A fire hydrant alarm button is installed inside the fire hydrant box. Fire alarm buttons are installed around the methanol synthesis plant, the distillation unit plant, and the tank area. Install one dedicated fire-fighting intercom telephone system with recording function in the fire control room ； In addition to having dedicated fire telephone jacks installed on the manual alarm buttons, dedicated fire telephone extensions are also provided in locations such as the fire pump room, power distribution room, and security duty room ； The fire control room should be equipped with direct external dialing phones, and the dedicated phone network for firefighting purposes must constitute an independent fire communication system. 7. The methanol storage tank is equipped with high and low liquid level alarms.
The height, length, and width of the tank farm cofferdam are determined based on the volume of the storage tanks and the number of such tanks
One more thing! ! ! Lightning protection devices and grounding systems
To meet environmental requirements, it may also be necessary to install an exhaust gas washing system
What is the relationship between exhaust gas washing in methanol storage tanks and climate? With an average annual temperature of -12 degrees, is it still necessary to carry out washing and absorption?
Methanol volatility is particularly low at low temperatures, and there is also an internal floating disk plus nitrogen. Is it necessary? Average annual temperature: -12 degrees
Safety comes first in terms of design; without fire dikes, it’s impossible to pass the fire safety inspections, let alone carry out production.
Is insulation for the crude methanol storage tank necessary? Which expert can give some advice? There is a washing tower, and the washing water is sent to the crude methanol tank. The temperature is low for long periods of time.
The main function of the insulation layer is to maintain the temperature of the methanol tank, protect the tank from environmental corrosion, and improve its safety in use.
Internal floating disk + nitrogen. Is it necessary to use nitrogen for a 200-cubic-meter crude alcohol tank?
Cofferdams, foam agents, subsea valves are required, as well as explosion-proof lights
Should fire extinguishers be placed inside fire dikes? It’s not safe to go in to get it; besides, a fire barrier over a meter high standing outside is sufficient to put out the fire. Please, an expert, give me an explanation. Thank you. Is it still necessary to install fire cannons? Aren’t foam fire hydrants sufficient? There doesn’t seem to be any such regulation in the standards. Also, is there a requirement that the distance between fire hydrants around the tank area should not exceed 60 meters? I’ve seen others set it up that way~ but I don’t think it’s necessary; having enough water for firefighting is sufficient. Could some expert give me an explanation? Thank you very much~~