Winter is approaching – what anti-freezing measures do the factories where you work have in place?

Cold and frost protection measures； During the period when the unit is not in use, it is necessary to strengthen equipment inspections to prevent damage caused by freezing, thereby ensuring ； Steam turbine major: ； 1. Close all doors and windows, as well as the ventilation baffles on the top of the machine room ； ； 2. When the temperature in the turbine hall is 5°C, supply heated steam on-site to control the temperature inside the hall ； 3. The condensate water storage tanks operate in parallel; pay attention to the transfer of demineralized water from the two units to the condensate system ； 4. Under normal conditions, pipelines No. 1 and No. 2 for water replenishment should operate simultaneously; Pipeline No. 1 for replenishment ； 5. When the water tower is out of service, the standby water tank is filled using the main return water pipe of the emergency circulating water system ； 6. In areas where the ambient temperature at the site is low, appropriate measures should be taken to prevent cold and freezing damage. During periods when the units are not in use, it is necessary to conduct regular inspections of the equipment to avoid damage caused by freezing, thereby ensuring safe operation. Therefore, specific measures against cold and freezing have been established; please comply with them carefully:

Steam turbine specialty: 1. Close all doors and windows, as well as the ventilation baffles on the top of the machine room； 2. When the temperature inside the turbine building is 5°C, activate the on-site steam heating system to maintain the ambient temperature in the building at above 5°C ； 3. The condensate water storage tanks operate in parallel; ensure that the opening degree of the adjustment valves for the demineralized water flowing to each tank is not less than 5%, and verify on-site that water is flowing ； When the unit does not require water replenishment, the condensate storage tank is kept in an overflow state to prevent freezing; the condensate and steam pump is started once per shift to prevent freezing in the inlet pipeline of this pump ； 4. Under normal conditions, pipelines No. 1 and No. 2 for water replenishment should operate simultaneously: Pipeline No. 1 supplies water to the recycled water system, while Pipeline No. 2 is used to replenish water in the water tower and the integrated pump room ； Under special circumstances, the operation mode is adjusted so that both makeup water pipelines maintain a flow rate of not less than 100 t/h ； 5. When the water tower is out of service, the water storage tank is filled with water using the emergency circulating water return main to prevent freezing ； 6. Install a certain number of thermometers in areas where the ambient temperature at the machine site is low; carry out regular inspections, and adjust the number of heating units in use as well as the pressure in the heating manifolds in a timely manner to maintain the ambient temperature at the machine site between 5 and 15°C ； When the adjusted ambient temperature is below 5°C, report to the shift supervisor, duty manager, and relevant leaders promptly ； 7. The closed-water system shall remain in operation. If the machine or boiler (the air compressor and chemical systems should use water supplied by Unit 2) needs to be shut down for maintenance, the closed-water system of the unit to be taken out of service must be thoroughly inspected. This can only be carried out when the ambient temperature is above 6°C and with the approval of the shift supervisor; after shutdown, increased surveillance and inspection of all systems and equipment are required ； 8. Strengthen the inspection of water-based fire protection systems and equipment such as fire hydrants and deluge valves; contact relevant parties for prompt handling in case of any abnormalities detected ； 9. The outdoor drain point on the heating main pipe for extracted steam from Unit 2 remains continuously open when the pipeline is shut down; it is necessary to check each shift that the drain pipeline remains unobstructed ； 10. For the units that are out of service, it is necessary to test whether the heaters for the main oil, auxiliary oil, seal oil, and EH oil systems are functioning properly. 11. When operating in single-unit mode, strict adherence to the \"Anti-freezing Measures for the Circulating Water System in Single-Unit Operation\" is required for preventing freezing. 11.1. When a 300MW unit is operating in single-unit mode, the standby unit should keep the connection valves for the circulating water supply open in order to keep the open-type pumps running; it is important to ensure that the flow rate of these open-type pumps remains stable ； Pay attention to checking the flow of water to various users in the open-system, to ensure normal water flow ； 11.2 During shutdown, the circulating return water shall not be sent to the tower; the temperature of the circulating water inlet must remain above 5°C to prevent the water tank from freezing. The temperature of the water tank is raised by using the connecting pipe for the circulating return water ； 11.3 The wind shields on the water tower of the standby units must be fully installed ； 11.4: For the standby units, fully open the electric valves at the inlet of the condenser’s circulating water, and open the electric valve at the outlet of the circulating water by 5 degrees. Use the connecting valve for circulating water supply to maintain water flow; regularly check the air release valve at the outlet of the condenser’s circulating water and close it once water starts flowing out of it ； When starting the circulating water pump to prevent freezing in a unit that is not in operation, pay attention to adjusting the electric valve at the outlet of the condenser’s circulating water; ensure that the pressure at the inlet of the condenser’s circulating water does not exceed 0.2 MPa ； 11.5. Standby units must, based on the outdoor temperature during the shift, consult the shift supervisor regarding starting the auxiliary systems on their own side

Operation of the circulating water pump: 1) When the outdoor temperature during shift is above -10°C, it is not necessary to start the circulating water pump on this side； 2) When the outdoor temperature during shift is between -10°C and 20°C, the third shift operator shall start the small circulation water pump on the local side and operate it for 30 minutes ； 3) When the outdoor temperature during shift is below -20°C, start the small circulation water pump on the machine side for 30 minutes per shift ； For each shift, open the make-up water valves No. 1 and No. 2 of towers 1 and 2 associated with the units that are not in operation once each; keep them open for 5 minutes before closing them. Strict control must be exercised to prevent the water tanks in these towers from overflowing ； When implementing this measure to start the small circulation water pump for anti-freezing purposes, it is necessary to clearly record the start and stop times as well as the ambient temperature in a note.

Boiler specialty: 1. Personnel in all positions shall conduct a comprehensive inspection of the production site; any deficiencies found must be reported and addressed promptly. 2. Conduct a thorough inspection of the heating system; any defects found should be reported promptly, and efforts should be made immediately to eliminate potential issues related to heating so that the system is in a ready state and can be put into use at any time. Heat should be supplied to the site as appropriate depending on the ambient temperature; it should be provided when the ambient temperature is below 5°C. When the ambient temperature at the site is above 15°C, heating of each group should be stopped and the pressure in the header should be reduced ； If it remains above 15°C after adjustment, the on-site heating steam should be stopped. When the ambient temperature is low and heating systems are activated, it is necessary to check that all units are functioning properly. If heaters and hot air curtains are in use yet the ambient temperature remains below 5°C, it is necessary to request the installation of a carbon furnace to maintain a suitable room temperature. 3. Prevent water accumulation and freezing in various pipelines. The insulation of various pipes must be complete, especially that of pipes located outdoors; it is also necessary to ensure proper circulation of the fluid inside the pipes. When the flow of the medium stops for various reasons, all drainage and waste discharge points should be opened to allow the fluid to be drained completely (such as in the case of closed-loop cooling water), in order to prevent the equipment from being damaged by freezing. 4. The doors and windows at the production site should be thoroughly inspected; the glass should be properly installed and carefully maintained. Doors and windows that need to be closed must be shut tightly; if a window cannot be closed properly, it should be reported promptly for handling. If the glass in doors or windows is damaged, it is necessary to inform the relevant authorities promptly so that repairs can be carried out. Curtains should be used to cover the doors inside the factory building, and depending on the weather conditions, the relevant maintenance teams should be contacted to carry out the repairs ； 5. After the boiler is shut down, it should be maintained and protected from freezing by methods such as heating it while it is still in use or draining water from it when it is hot. After shutting down the boiler, if there is water inside and the temperature of the boiler water is below 10°C, water should be periodically filled into and drained from the boiler. When draining, it should be done alternately at each low point. The access doors and dampers of standby boilers shall be closed, and boilers under maintenance must have measures in place to prevent cold air from entering. When it is necessary to drain water from the boiler, all the drain valves, water release valves, and air valves should be opened fully to ensure that all water remaining in the system is drained, thereby preventing the drainage system from freezing. When the pressure in the boiler drum drops below 0.1 MPa, open the main and reheat steam drain valves to prevent water from accumulating in the superheaters, reheaters, and their drainage systems. 6. For pipelines that discharge steam outdoors, such as those in expansion tanks, regular inspection and cleaning are necessary to remove ice formed as a result of steam cooling. 7. When cleaning high areas, the cleaning team should try not to open windows; if opening them is necessary, they must be closed immediately after cleaning is completed, and this must not be forgotten. In winter, it is necessary to conduct more frequent inspections of equipment that is prone to freezing or those located in areas with low temperatures near doors and windows. Thermometers should be installed in key areas, and measures should be taken promptly to raise the temperature when it drops below 5 degrees Celsius. 8. When inspecting equipment at various outdoor positions, one must be aware of the risk of slipping on ice and snow to prevent personal injuries. 9. Strengthen the maintenance of outdoor water supply pipes, steam supply pipes, and drain pipes; ensure proper drainage from the pipes connected to the equipment, and conduct regular inspections.

Anti-freezing measures for fuel pipelines: 1. When the outdoor ambient temperature is between 0°C and -10°C, the duty personnel must start the fuel pump and run it for 20 minutes each day. 2 When the outdoor ambient temperature is between -10 and -15°C, the fuel pump should be started for 20 minutes once a day or every three days. 3 When the outdoor ambient temperature is between -15 and -20°C, start the fuel pump for 20 minutes per shift. 4 When the outdoor ambient temperature is below -20°C, start the fuel pump to run continuously. 5 After the boiler stops operating, force the fuel supply solenoid valve to open; once the fuel pump starts, ensure normal oil circulation in front of the furnace. 6 After the fuel pump starts, check that the fuel supply and return pressures for Reactors 1 and 2 are normal. 7. Note the start and stop of the fuel pump in the log for Reactor No. 1. 8 Try to avoid carrying out maintenance on the fuel pipelines in winter; if maintenance is necessary, drain all the oil and water stored in the system, and install temporary heating devices if required.

Anti-freezing measures for chemical plants in winter: Anti-freezing is the biggest challenge for the safe production of chemical enterprises during winter. Our company is located in Jilin, where winter temperatures range from minus 12 to minus 24 degrees. The common anti-freezing measures for process pipelines include heating and insulation. The importance of anti-freezing is understood by all operators; the issue now is to achieve savings while still ensuring safety against freezing, without allowing water to flow at an excessive rate. Fire protection piping systems are equipped with electric heating; energy conservation and emission reduction are important issues for us, and they are also the focus of our inspections. Companies should keep an eye on local weather forecasts at all times, and based on weather changes, take early preparations and establish appropriate guidelines for their teams. General measures to prevent freezing and condensation are formulated according to the characteristics of each facility, and special attention should be paid to aspects that the teams may not be able to handle or consider. Ensure proper venting, condensate drainage, and heat tracing in key areas such as water, steam, air, and oil systems to maintain unobstructed flow, and conduct regular inspections. Automatic electric heat tracing for equipment piping systems ； The remaining anti-freezing pipelines remain under continuous electric heating. To prevent freezing in chemical plants during winter, the main focus is on ensuring the normal operation of the processes. This involves checking whether the media inside the equipment and pipelines are affected by low temperatures in winter and whether this affects the requirements of the processes. The main solutions are to use rock wool for insulation or to install electric heating elements for warming. There are several ways to prevent freezing in winter. One method is to use heating and insulation; there are two types of electric heating: electric heat tracing and steam heating. Second is draining; unused pipelines should be drained and purged in a timely manner. Third, make small emissions at the low point or circulate fluid to ensure flow. Common methods for anti-freezing include steam tracing, electric tracing, insulation materials, and hot water tracing. Tasks to be carried out for freeze and condensation prevention in winter: 1. Activate all heating systems and conduct a thorough inspection to ensure that condensation is drained from the lowest points. 2. After shutting down the machinery and pumps, purge them with nitrogen. 3. Regularly drain condensate from the bottom of the instrument air line air tank. Prevent instrument air from containing water. 4. If the device’s water line cannot be drained, keep it slightly open to prevent freezing and cracking. 5. When purging the device, the drain bottom valve should be flushed until steam is emitted and no liquid comes out. 6. Wear a safety helmet when going out for inspections. 7. To save energy, try to avoid discharging under pressure whenever possible.

Insulation and anti-freezing measures for chemical plants in winter 1. Insulate the pipes in the stagnant water areas of the workshop’s circulating water system； The deactivated circulating water pump was subjected to reverse flow measures and its contents were completely drained. 2. For equipment that is not in use in the workshop, such as make-up water pumps, circulation water pumps, coolers, condensers, etc., measures such as draining water and conducting regular inspections should be taken. Compressor cooling water is regularly checked by operators to ensure that the water valve remains open at all times. 3. The drainage pipelines of the adsorption tower, desulfurization tower, water washing tower, and gas-liquid separator outside the workshop are protected against freezing using electric heat tracing. Freezing is prevented by promptly draining the water separators and coolers in the workshop after they are shut down. 4. When indoor heating is turned off, safety facilities such as tap water, eye wash stations, and fire extinguishers in the workshop are kept from freezing using electric anti-freezing systems. 5. If water is spilled on the workshop floor or platforms, clean it up immediately to prevent freezing. Workshop staff should enhance their safety and precaution awareness when going on platforms and climbing stairs. 6. When workshop staff carry out maintenance work on the framework and the requirements for working at heights are met, all necessary safety precautions must be taken: wear safety helmets and harnesses, and there must be a dedicated person to supervise the work. High-altitude work in strong winds, carried out when gust speeds reach level 6 (10.8 M/S) or higher, constitutes special high-altitude work; such work can only be undertaken with the approval of the general manager. In case of rain or snow, clean the stairs promptly. 7. During this period, workshop personnel should increase the frequency of inspections; should any abnormalities be detected, they must promptly report them to their superiors.

The moderator’s answer was incredibly detailed

Anti-freezing measures for winter pipelines: 1. Process water lines. For any installations on the ground that use a small amount of water, it is necessary to ensure that there is a drain valve at the end of the pipeline to maintain a continuous flow of water and prevent freezing; where possible, insulation should be added to the pipeline. 2. For water lines that are used intermittently, electric heating tapes must be installed for insulation; otherwise, they cannot be used. 3. For water lines that are not in use during winter, the flanges on both ends should be removed to drain all the water remaining in them. If possible, industrial air should be used for purging to ensure that the pipes do not get filled with water again. If the valves are not airtight, blind flanges should be installed at the flanges on both ends, and these should be registered and labeled accordingly. 4. For some pipelines that are not used in normal production, as they remain inactive for long periods of time, water may accumulate in their dead corners and freeze; once these pipelines need to be used, this can lead to blockages and disrupt production. For such pipelines, before winter arrives, it is necessary to clean and flush them with an appropriate flow rate, then close the relevant valves to keep them in a standby state. 5. For the fire hydrants in the fire water supply system, as well as the valve chambers for these systems, it is necessary to close the valves located in those chambers and drain the water from the hydrants, so that they are ready for use at any time. A double-layer manhole cover should be used in the fire well (one of which is a thermal-insulating manhole cover). Freezing occurs: Once the equipment freezes, it should be thawed using steam or hot water. The thawing of cast iron pipes and equipment must be done slowly to prevent cracking. It is prohibited to heat frozen pipes or equipment while they are still sealed; first, the seals must be removed to allow air to escape. Horizontal pipes should be thawed from bottom to top, while vertical pipes should be thawed from top to bottom. Any cracks that appear must be reported.

I. Anti-freezing and anti-condensation measures for the units in the raw gas area: 1. Stop the water supply to the raw gas cooler and drain the water stored in the tank. 2. Drain water from the low-point drain valve of the raw gas buffer tank, then close it. 3. Stop the make-up water pump and the circulation water pump in the wash tower; drain all the water from within the tower as well as from the pump pipelines, and empty the water level gauges. 4. Drain water from the low-point drain valve of the gas-liquid separator, then close it