Does a atmospheric distillation tower need a safety valve?

Safety valves must also be installed on pressure vessels at normal pressure

The container mentioned by the original poster can no longer be considered a normal-pressure container, as it generates certain pressure under abnormal conditions; however, the original poster did not specify how high that maximum pressure is. Based on the situation described by the poster, the following recommendations are given: 1. Install safety valves: Determine the appropriate safety valves by referring to \"HG-T 20570.2-1995 Guidelines for the Installation and Selection of Safety Valves\" and \"GB-T12241-2005 General Requirements for Safety Valves\", taking into account the properties of the medium inside the tower and the maximum pressure levels ； 2. No safety valve: If no safety valve is installed, an online pressure alarm and an emergency pressure relief device should be provided; in the event of pressure buildup, an audible and visual alarm will be triggered and the emergency pressure relief device will activate. If conditions permit, it is best to install a linked system.

I have the same question too. Under normal pressure conditions, a breathing valve is installed to maintain pressure – but is it really necessary to use a safety valve as well?

Comply with the provisions of GB50160-2008; the relevant clauses are as follows: 5.5.1 Under abnormal conditions, safety valves shall be installed on the following equipment that is prone to overpressure: 1. Pressure vessels with a maximum operating pressure at the top of 0.1 MPa or higher； 2. Distillation towers, evaporation towers, and stripping towers with a maximum operating pressure at the top greater than 0.03 MPa (except those in which steam from the top of the stripping tower is fed into another distillation tower) ； 3. The outlets of each stage of reciprocating compressors, or the outlets of positive-displacement pumps such as electric reciprocating pumps, gear pumps, and screw pumps (except those equipped with safety valves of their own) ； 4. Where the equipment connected to the outlet of a blower, centrifugal compressor, centrifugal pump, or steam reciprocating pump is not capable of withstanding its maximum pressure, the outlet of the blower, centrifugal compressor, centrifugal pump, or steam reciprocating pump ； 5. Equipment in which flammable gases or liquids expand when heated, potentially exceeding the design pressure ； 6. Equipment with a maximum operating pressure at the top of 0.03~0.1 MPa should be installed in accordance with process requirements. This provision is explained as follows: Equipment that requires the installation of safety valves includes the following: 1. According to **current regulations, equipment with an operating pressure of 0.1 MPa (gauge) or higher is classified as a pressure vessel; therefore, safety valves must be installed. Most towers for gas-liquid mass transfer are equipped with safety valves, as reasons such as power outages, water supply interruptions, interruptions in the reflux stream, excessive stripping volume, or an excessive amount of water (or light components) in the feed material can all lead to a sudden increase in the gas-phase load and cause overpressure in the equipment. Therefore, safety valves should be installed in any tower where the operating pressure at the top is greater than 0.03 MPa (gauge). 3 Safety valves are installed at the outlets of both compressors and pumps; some of these safety valves are attached to the machine body, while others are mounted on the pipes. Because the pump outlet pipe may become blocked for some reason, and the outlet valve may close due to incorrect operation.

Safety valves should be installed on the tower as a precaution

I’ve had this problem for a long time; it’s the same situation with a project I’ve been working on. In my opinion, what was said on page 5 is detailed enough to help determine whether a safety valve is necessary or not. However, the company doesn’t want to install one, arguing that since the pressure is at atmospheric level, no safety valve is needed. But the standards are clear: whenever the operating pressure at the top exceeds 0.03 MPa (gauge), a safety valve must be installed. There is another note in the old provisions: full condensation distillation tower——. But it isn’t included in the new provisions, so it’s difficult to determine at the handover stage whether to use the old standards during construction or the new ones once it’s completed. I think for safety’s sake, it’s best to follow the new method whenever possible.

This post was last edited by hkj0221 on 2009-7-30 at 16:16. Safety devices are definitely necessary, but I suggest installing an explosion-proof membrane instead; since it’s a device that operates at normal pressure, overpressure only occurs under abnormal conditions. If a safety valve is used and remains in contact with the materials for a long time, problems such as jamming and corrosion are likely to occur

Atmospheric towers generally have two pressure relief points. Vapor-phase outlet liquid seal tank and reflux tank. When there is a problem with the cooling water, the operator can shut off the steam. It won’t overpressurize.

In atmospheric pressure towers, safety valves are not required for non-toxic media