Arrangement and explosion protection of explosion-hazardous plants and warehouses

Layout and explosion protection of explosion-hazardous silos and warehouses

I. General layout

1. Explosion risk of Class A, B plant, warehouse should be set up independently, and should be open or semi-open, its load-bearing structure should be reinforced concrete or steel frame, row structure.

2. explosion-hazardous plant layout preferably rectangular, and the prevailing wind direction should be perpendicular or angle of not less than 45 °, in order to effectively utilize the penetrating wind to dissipate explosive gases in the mountainous areas should be arranged on the windward side of the hillside and well-ventilated places.

3. explosion-proof plant should be set up separately, such as must be adjacent to non-explosion-proof plant, only one side of the adjacent, and between the two firewalls or explosion-proof wall separated. Adjacent to the two plants should not be directly connected to the door, in order to avoid the impact of the explosion shock wave.

II. Floor plan and spatial arrangement

1. Main control room and sub-control room

(1) The general control room of the explosion hazardous Class A and B plants shall be set up independently.

(2) There is an explosion risk of A, B class plant sub-control room should be set up independently, when set up adjacent to the external wall, should be used fire-resistant limit of not less than 3.00h fire partition wall and other parts of the separation.

2. Explosion hazardous areas

(1) There is an explosion risk of A, B production parts, it is appropriate to be arranged in a single-story plant against the outside wall of the pressure relief facilities or multi-storey plant on the top floor against the outside wall of the pressure relief facilities nearby.

(2) There is a risk of explosion equipment should be avoided in the plant beams, columns and other major load-bearing members of the arrangement.

(3) Stairwells, outdoor staircases or areas with explosion hazards in the explosion hazardous area should be equipped with door buckets and other protective measures. The partition wall of the door hopper shall be a fireproof partition wall with fire resistance limit of not less than 2.00h, and the door shall adopt Class A fireproof door and shall be staggered with the door of the stairwell.

3. Plant emitting combustible gases, combustible vapors

(1) For Category A plants emitting lighter combustible gases and flammable vapors than the air, it is appropriate to use lightweight roof panels as the pressure relief area. The roof should be as flat and free of dead space as possible, and the upper space of the plant should be well ventilated.

(2) Category A plants emitting heavier combustible gases and flammable vapors than air and Category B plants with dust and fiber explosion hazards shall comply with the following provisions:

Non-sparking floors should be used. Anti-static measures shall be taken when insulating materials are used for the overall surface.

The interior surfaces of plant that emit combustible dust and fibers should be flat, smooth and easy to clean.

It is not suitable to set up the gutter in the plant, if it is necessary to set up, the cover should be tight, the gutter should take effective measures to prevent combustible gases, combustible vapors and dusts, fibers from accumulating in the gutter, and it should be sealed with fireproof materials at the connection with the adjacent plant.

4. Plants and warehouses using, producing or storing liquids of categories A, B and C

(1) The pipes and ditches of plants using and producing liquids of categories A, B and C shall not be connected with those of neighboring plants, and the sewers shall be equipped with grease traps.

(2) Warehouses for liquids of categories A, B and C shall be equipped with facilities to prevent the dispersion of liquids. Warehouses of items that will burn and explode when wet should be equipped with measures to prevent water impregnation.

5. Underground, semi-basement

(1) Class A and B production sites should not be located underground or semi-underground.

(2) Category A and B warehouses should also not be located underground or semi-subterranean.

III. Pressure relief

1. Explosion-hazardous plant or explosion-hazardous parts of the plant should be equipped with pressure relief facilities.

2. Pressure relief facilities should be used lightweight roof panels, lightweight walls and easy to relieve the pressure of the doors, windows, etc., should be used in the explosion of safety glass and other materials that do not produce sharp fragments.

3. Pressure relief facilities should be set up to avoid densely populated places and major traffic roads, and should be close to the parts of the explosion risk.

4. The mass of lightweight roof panels and walls used as pressure relief facilities should not be greater than 60kg/㎡. Pressure relief facilities on the roof should take measures against the accumulation of snow and ice.

5. For Category A plants emitting lighter combustible gases and vapors than the air, it is appropriate to use lightweight roof panels as the pressure relief area. The roof should be as flat as possible, without dead space, and the upper space of the plant should be well ventilated.

IV. Calculation of pressure relief area

Pressure relief area calculation formula:

A=10CV2/3   A – Pressure relief area (㎡); V – Volume of the plant (m³); C – Pressure relief ratio

(1) Length-to-diameter ratio: the longest dimension of the geometric dimensions of the building plane and its cross-section perimeter of the product and 4.0 times the ratio of the cross-sectional area of the building.

(2) When the length-to-diameter ratio of the plant is greater than 3, it is appropriate to divide the building into multiple calculation sections with length-to-diameter ratios not greater than 3, and the common section in each calculation section shall not be used as the pressure relief area.

V, how to do a good job of high-temperature waterproof fire and explosion-proof measures

Category A and B warehouses are warehouses where hazardous chemicals are stored and where measures against heat, water, fire and explosion are required to ensure safety.

1. Measures against high temperatures: In category A and B warehouses, it should be ensured that the temperature does not exceed the requirements for the storage of hazardous chemicals. The following measures can be taken: installing air-conditioning or ventilation systems inside the warehouse to control the temperature; insulating the warehouse with heat-insulating or heat-insulating materials; and regularly checking and maintaining the cooling equipment to ensure that it operates properly.

2. Waterproofing measures: Category A and B warehouses should be waterproofed to prevent rainwater or other liquids from entering the warehouse and causing chemical leakage or contamination. The following measures can be taken: check the sealing of warehouse roofs and walls and repair any leaks or seepage; ensure that the drainage system is unobstructed and that drains and pipes are cleaned in a timely manner; and install waterproof coatings or flashings where necessary.

3. Fire prevention measures: Category A and B warehouses should be equipped with fire prevention facilities to minimize the risk of fire. The following measures can be taken: installing a fire alarm system to detect and report fires in a timely manner; equipping fire extinguishers, foam fire extinguishing systems or dry powder fire extinguishing systems and other fire-fighting equipment; regularly inspecting and maintaining such equipment to ensure its normal operation; and keeping the aisles in the warehouse clear to facilitate evacuation.

4. Explosion-proof measures: Flammable and explosive substances may be present in category A and B warehouses, and explosion-proof measures need to be taken to protect the safety of personnel and facilities. The following measures can be taken: use explosion-proof electrical equipment, such as explosion-proof switches and explosion-proof lamps; ensure that electrical equipment in the warehouse meets explosion-proof requirements; limit the generation of open flames, static electricity and sparks; and provide appropriate explosion-proof personal protective equipment.

5. Regular inspection and maintenance: Regularly inspect the effectiveness of measures against heat, water, fire and explosion in category A and B warehouses and carry out the necessary maintenance and repairs. Ensure the integrity and normal operation of protective facilities and equipment.

6. Employee training and awareness-raising: Train warehouse staff in the management of hazardous chemicals and safe operation, so that they are aware of the relevant protective measures and response measures in case of emergency. Raise employees’ awareness of the importance of safety and the correct use of protective facilities.

By taking the above measures, the risks of heat, water, fire and explosion in Category A and B warehouses can be minimized and the safe storage and management of hazardous chemicals can be ensured. Meanwhile, regular maintenance and staff training are the key to preventing accidents. Please formulate specific protective measures according to the actual situation in conjunction with professional and technical guidelines and legal and regulatory requirements.