Regarding anti-freezing measures

Add an accompanying pipe, with steam blown alongside. Another approach is to manage the backflow uniformly, assigning different types of discharge fluids to separate collection mains (or tanks) for subsequent unified treatment, in order to minimize the impact.

Use a large main valve, with a smaller valve added behind it. Wrap 20 large-sized tubes around the pipelines that need to be protected from freezing; place the outlets as closely together as possible to facilitate checking whether the tubes are blocked or not.

Is the insulation thickness up to requirement? Otherwise, we’ll have to use heat tracing

Key points for frost prevention in winter: When operating in winter, the main concern is preventing equipment and pipelines from expanding due to the low temperatures around them, which could lead to production disruptions and malfunctions of control devices. To address this, the following points should be taken into consideration: 1. Install insulation boxes for instruments in areas where it is necessary. 2. Identify the dead ends in the pipeline and take measures to prevent freezing and cracking. 3. Use insulation materials to enhance the insulation of the device. 4. Carefully monitor the operation of the equipment to prevent freezing in pipes and equipment, and take measures in areas where freezing is possible. 5. Strictly prevent leaks in equipment and pipelines, as freezing is likely to occur at the leakage points, affecting the normal operation of the system. 6. In the event of a stoppage or accident, as long as the entire system has not been completely shut off and water has not been fully drained from the system, steam supply must be maintained. 7. Some pipelines without heat tracing may freeze during shutdown; therefore, all liquids and water must be drained within half an hour after shutdown, taking care to handle the discharge of toxic liquids. 8. When the surrounding air temperature is below zero degrees, the heating of the equipment and pipelines must increase by 25°C per hour once the device is started up; at this time, the temperature difference between the inlet and outlet of the equipment should not exceed 100°C. 9. When pressurizing the device during startup, the pressure must be increased gradually – 0.25 times the operating pressure can be applied in the first hour, with an additional 0.25 times the operating pressure added every 15 minutes. It is crucial not to increase the pressure too quickly.

Adding heating is the best option, but it’s a bit wasteful; having a continuous flow of water is ideal (it’s best to collect the water at regular intervals, otherwise it’s too wasteful)

In areas with steam heating, it is necessary to ensure that the traps are functioning properly. In areas with electric heating, it is important to regularly check the temperature of the heating wires. It is essential to keep the pumps in a standby mode with no fluid inside, and the pipelines must be emptied and dried out. As long as the routine inspections are thorough and careful, there should be no problems with freezing protection

Currently, we use a combination of steam heating and electric heating for anti-freezing purposes; in pipes with larger diameters, steam pipes are installed, while for pipes with relatively smaller diameters, electric heating elements are used, and the results are quite good.

Anti-freezing and anti-condensation measures for the facility: Anti-freezing and anti-condensation measures in winter are essential means to ensure safe production. To prevent any occurrence of freezing or condensation incidents, these measures should be carried out in accordance with the principle of \"prevention first, elimination as a supplement\", taking into account the characteristics of the facility. Strengthen the receipt, delivery, use, and management of items that are prone to freezing or solidifying, and abide by relevant rules and regulations in order to ensure safe production. The specific measures are as follows: (1) Before winter arrives, conduct a comprehensive inspection of the equipment and make preparations for winter use, such as providing insulation and steam heating for equipment and pipelines, checking whether there are any dead corners in the equipment, pipelines, and valves, and ensuring that the drain valves function properly. Also, take care of windows, glass, and heating systems. (2) Equipment and pipelines that are taken out of use in winter must first be cleaned with steam; for those that cannot be cleaned with air, the drain valves at the lower positions must be opened to remove any accumulated water. (3) For equipment that is temporarily shut down in winter, it is necessary to ensure a slight flow of return water or steam to prevent the pipelines from freezing. (4) During winter operations, the steam lines, the feedwater and return water lines, as well as the drain valves on the heat tracing lines should be slightly opened depending on the temperature conditions, in order to prevent the valves and lines from freezing damage; the traps should remain unobstructed and functional. (5) The drain valves or vent valves on the fire steam lines throughout should be slightly opened to allow steam to escape and prevent freezing. (6) For the industrial air and purified air of the device, inspection and water cutting operations should be intensified, and the rubber hoses for exhaust steam in various locations should be connected to the sewer for condensate discharge. (7) If it is found that the valve is frozen and cannot be opened, especially in the case of cast-iron valves, it is prohibited to strike it with a wrench or other tools. Instead, the valve should first be closed, then warmed up using steam (or water) before attempting to open it. (8) During winter, the heat tracing lines of all pipelines must always be supplied with steam and water to ensure they remain unobstructed. For the condensate pipes leading to the atmosphere and the drainage valves, a method of slight steam and water discharge should be employed. (9) When the plant is shut down for winter due to a lack of steam and water supply, air should be used to thoroughly purge all steam and water lines, isolate them from the main pipelines outside the plant, or drain them at an appropriate location. (10) During the winter shutdown period, all heating equipment, pipeline trace heaters, and steam systems should generally continue to receive a small amount of steam supply, while all coolers and cold water lines should also continue to have a slight flow of water to keep the pipelines unobstructed and prevent them from freezing. (11) In winter, the degree of steam and water drainage can be adjusted according to the time of day – morning, noon, or evening – as well as the temperature conditions; regular checks are necessary, as there is no one-time solution. (12) When a problem is detected with the instrument bypass heater, notify the instrument maintenance team promptly to handle it. (13) Strengthen routine inspections to prevent freezing, ensure smooth operation, and maintain safe production. (14) To prevent the medium inside the standby pump from freezing, the following methods should be adopted: a) Close the inlet and outlet valves, open the vent valve and the drain plug on the pump body, and drain all the liquid accumulated inside the pump. b. Slightly open the bypass valve of the pump outlet check valve and open the pump inlet valve; this allows the fluid from the pump in use to flow back through the standby pump body to prevent freezing.