Winter freeze prevention

Thread Content

The winter climate is dry and cold, with frequent cold snaps and irregular temperature fluctuations. In the north, there are rain, snow, freezing conditions, strong winds, and heavy fog, while in the south, there is freezing rain and frost. The occurrence of extreme and severe weather conditions is on the rise, which has an adverse impact on the safe production of chemical enterprises; as a result, the probability of certain accidents also increases. Image: The impacts of severe winters on the safe production of enterprises are mainly manifested in the following aspects: 1. Severe winters cause equipment and pipelines to freeze and crack, leading to leaks of hazardous chemicals ； 2. Freezing of materials inside equipment and pipelines leads to blockages, affecting normal operation ； 3. Instruments used outdoors fail to function properly due to the freezing of the medium being measured, resulting in distorted readings ； 4. It’s cold outdoors; the temperature of reactors installed in open areas cannot be guaranteed, affecting the reaction conversion rate ； 5. The material pipelines exposed to the outdoors are not adequately warmed; this makes them prone to water hammer-induced ruptures during material feeding, resulting in material leakage ； 6. Roads and steel ladders become slippery due to ice, increasing the likelihood of people slipping and getting injured, as well as the risk of them falling ； 7. The need for insulation and ventilation in outdoor factories creates a conflict, leading to the accumulation of toxic and flammable gases and increasing the risk of explosions and poisoning ； 8. In outdoor open-air work, due to workers having limited dexterity, work efficiency and quality decline, making it easy for potential hazards to arise ； 9. Outdoor workers wear heavy clothing, which increases the chances of contact with equipment, pipes, and materials, thus making accidents more likely ； 10. Raw and auxiliary materials such as raw coal and ore stored outdoors have frozen due to low temperatures, affecting normal production ； Image 11. Emergency facilities freeze due to the cold, reducing their functionality and affecting their emergency use ； 12. In winter, frozen roads become slippery; the transport of hazardous chemicals is restricted, affecting the inflow and outflow of materials for enterprises ； 13. Operators fear the cold; their tendency to take risks increases, and violations of regulations become more common. Failure to detect hazardous situations in time may lead to accidents ； 15. The dry climate in winter increases static electricity buildup, leading to fire and explosion accidents. Image: The key focus of winter safety production should be on preventing freezing. The following points deserve attention: (1) Drainage and condensate removal pipes for equipment and pipelines; (2) Flare knock-out drums; (3) Dehydration tanks and pipelines for liquefied hydrocarbons; (4) Transfer pumps used for transporting liquids with high freezing points; (5) Instrument air and air separation systems; (6) Standby equipment; (7) External power transmission lines.
Image: Enterprises should strengthen process management in the following operations as part of their winter freeze prevention efforts: (1) Special outdoor operations; (2) Dehydration operations for liquefied hydrocarbons; (3) Inspection activities at heights; (4) Road transportation operations.
Image: Enterprises must pay attention to the following areas when carrying out winter freeze prevention measures: (1) Slopes; (2) Stairs; (3) Eaves; (4) Previously open areas where temporary insulation measures have been implemented.
Image: Winter freeze prevention efforts in enterprises should start from the following aspects: First, ensuring inherent safety to minimize the impact of freezing on production. (1) Prevent the leakage of materials, reducing their direct contact with air as well as exposure to the cold external environment ； (2) For pipes installed outdoors, drip trays should be installed at the lowest points, and any accumulated liquid within the pipes should be drained promptly when the pipes are not in use ； (3) For pipes exposed outdoors that are at risk of being blocked by frozen material, pipe insulation should be considered, and heat tracing or steam jackets should be added if necessary ； (4) Install steam traps on steam pipes to promptly drain the condensate within the pipes ； (5) Pipelines and equipment involving materials that are prone to solidification should be arranged as much as possible inside the factory building ； (6) Buried pipelines should be laid below the permafrost layer. Image 2: Establish a winter anti-freezing and heat retention management system to clarify the requirements for anti-freezing measures as well as the responsibilities related to them. (1) Strengthen anti-freezing measures during critical periods, in key locations, and for important operations ； (2) Take preventive measures against freezing and condensation in advance for special outdoor work in winter, dehydration operations of liquefied hydrocarbons, inspections at heights, and during the period prior to the arrival of cold snaps. Third, pay attention to the safety of personnel in winter. (1) For areas prone to freezing and slipping such as ramps and stairs, spread sand or straw mats, install handrails, and remove ice promptly to prevent people from slipping and getting injured ； (2) For previously enclosed areas where temporary heating measures have been taken, ensure proper ventilation; equip personnel with portable gas detectors to detect leaks of toxic and harmful gases promptly ； (3) Install safety warning signs to alert people to pay attention to safety ； (4) Strengthen nighttime lighting efforts to prevent people from tripping and getting injured ； (5) Operations that pose a risk of burns to personnel should be equipped with portable eye wash stations ； (6) Take proper personal protective measures on the way to and from work to avoid injuries caused by vehicle collisions. Fourth, ensure proper anti-freezing measures for equipment, especially standby equipment. (1) Before shutting down rotating equipment, drain any material accumulated in the pump chamber and maintain flow in the pump cooling water system ； (2) Keep the drain and condensate removal pipes of the steam lines unobstructed, and ensure that pipe tracing and jacket steam systems operate normally ； (3) Keep areas such as the floors of static equipment, platforms, and the tops of storage tanks clean, with no standing water. Fifth, strengthen the maintenance and inspection of on-site monitoring components to prevent measurement errors caused by freezing. Sixth, strengthen the monitoring of moisture in instrument air to prevent valves from failing to operate due to water contamination in the instrument air. Seventh, formulate emergency plans, assign emergency response personnel, stock up on emergency supplies, and closely monitor information regarding the arrival of cold snaps and cold air to prevent potential problems. In short, the cold climate in winter poses a severe challenge to safe production. We must have a clear understanding of the situation, take targeted measures, and earnestly implement anti-freezing precautions to ensure safe production during winter.