Safety precautions for chemical plants

Safety precautions for chemical plants

Chemical production often uses flammable, explosive, toxic, and corrosive substances; production operating conditions sometimes require high temperature and high pressure; these factors bring great danger to chemical production. Chemical production must put safety first and implement the policy of "safety first, prevention first"!

1. Fire and explosion protection settings

In places prone to fire and explosion, facilities such as over-temperature and over-pressure detection instruments, alarms (sound and light) and safety interlocking devices should be fully installed.

Where combustible gas (steam) may leak and diffuse, a combustible gas concentration detection and alarm should be installed, and the alarm signal value should be set below 20% of the lower limit of the gas explosion.

All inert gas and combustion-supporting gas pipelines connected with flammable and explosive devices shall be equipped with facilities to prevent the intrusion of flammable and explosive substances, but it is not advisable to use a one-way valve alone.

Equipment that causes over-temperature and over-pressure due to the explosion and decomposition of reaction materials should be equipped with automatic and manual emergency pressure relief and discharge treatment tanks and other facilities.

A flame arrestor should be installed at the exit of the vent pipe of combustible gas (steam), and a stop valve should be installed at a place that is convenient for operation.

So that when a fire occurs at the outlet of the vent pipe, the gas source is cut off to extinguish the fire. Fire extinguishing pipe joints should be installed at the lowest part of the vent pipe.

2. Principles and practices of fire and explosion protection

Three conditions must be met for combustion to occur: combustibles, combustion-supporting materials and ignition sources.

l Control combustibles: prevent combustible gas, steam, dust and air from forming explosive mixtures;

l Eliminate ignition sources;

l Isolate air: remove combustion-supporting materials such as oxygen.

❶Electrical equipment must have a reliable grounding (zero connection) device.

The lightning protection and anti-static facilities must be intact and should be inspected regularly every year.

❷Electrical work must be professionally trained, qualified and certified, and labor protection equipment and electrical tools that meet safety requirements should be worn as required.

❸ Regardless of whether the high-voltage equipment is electrified or not, the person on duty shall not move alone or go over the mask to work.

If it is necessary to remove the barrier, a guardian must be present and meet the safety distance of the equipment without power failure.

❹In thunderstorm weather, when it is necessary to patrol outdoor high-voltage equipment, the patrolling personnel should wear insulated boots and should not approach the lightning protection device.

❺Before installing the grounding wire on the power failure circuit and equipment, discharge and test the electricity. After confirming that there is no electricity, hang the grounding wire on both sides of the work area.

Grounding wires should also be connected to branch lines that may be sent to power outage equipment and line work areas.

❻When a fire is started near live equipment, the flame is 1.5 meters away from the live part of 10 kV or less, and 3 meters for the flame above 10 kV.

❼When replacing the fuse, choose the fuse strictly in accordance with the regulations, and not replace it with other metal wires.