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Safety techniques for coke oven drying. Oven drying is a complex thermal process that takes place before a coke oven starts operating. During this process, in addition to strictly following the technical operating procedures, it is also necessary to adhere strictly to the safety procedures. I. Safety precautions for using solid fuel to heat ovens (1) During the oven heating process, unauthorized personnel must not enter the oven area or the flue corridors. (2) Under normal circumstances, welding and smoking are prohibited inside the furnace drying shed. (3) The canopies on both the machine and coke sides must not be too close or too low to the small stove. (4) Staff working on the coke oven roof and the control panels on both the machine and coke sides are prohibited from casually throwing down items such as bricks, iron objects, and tools. (5) When lifting operations are carried out above, workers are not allowed to walk below. (6) All personnel involved in the construction and furnace heating must wear appropriate personal protective equipment. (7) When walking on the furnace top, do not step on the coal loading hole covers. (8) A certain distance should be maintained between the coal yard and the ash yard; they must not be stored together. (9) Both the coal yard and ash yard should be equipped with good lighting facilities. (10) The drainage facilities at the coal yard and ash yard must be sound, and the transportation roads should be flat and unobstructed. (11) The hot ash and slag transported from the furnace bed to the ash yard should be extinguished promptly. (12) No one is allowed to approach the conveyor belt, and riding on the conveyor belt is strictly prohibited. (13) The sealing wall and fire bed must not be damaged with tools or other equipment. (14) When adding fuel to the small stove, the stoker should be careful not to damage the firebricks. (15) The removed ash and slag should not be placed near the furnace column or thrown under the control panel; instead, they must be taken to a designated location. (16) Wear asbestos gloves when taking temperature readings or removing sampling tubes to prevent burns from the hot iron tubes. (17) When taking temperature readings, prevent debris such as ash and slag from falling into the vertical flue. (18) When opening the fire sight cover, one should stand on the upwind side to prevent hot air currents from burning the face. (19) When opening the fire hole cover for temperature measurement, a safe fire hook should be used; no other unsafe tools shall be employed to prevent metal debris from falling into the vertical flue. (20) When using a thermocouple for temperature measurement, it is necessary to regularly check the tightness of the sleeve threads to prevent them from falling into the vertical flue. (21) When working on various parts, thermal repair plumbers should be careful to prevent refractory slurry from getting into their eyes. (22) When applying plaster to the walls of the carbonization chamber or the regenerative chamber, a safety ladder should be used; it is prohibited to work while standing on the furnace heating devices or switch controls. (23) Various operating tools for different types of work should be placed neatly, and it is strictly prohibited to touch live electrical wires while using them. II. Precautions for safe operation of furnaces using gaseous fuel (1) Gas pipelines and their fittings should be inspected and accepted in accordance with the technical specifications for the installation and pressure testing of pipelines and fittings used in coke ovens, to ensure the integrity of the piping system. (2) Before heating the furnace and lighting it, a gas explosion test should be conducted; only after it passes can gas be supplied to the furnace for ignition. (3) After the furnace start-up, if the suction in the smoke branch is less than 30 Pa, adjustments should be made immediately. (4) When the pressure of the gas pipelines on both the machine side and the coke side is less than 500 Pa, the small branch valve knobs of each stove should be turned down. After this measure is taken, if the gas pressure continues to drop, heating can be stopped. (5) During furnace drying, after replacing the gas orifice plates, a torch test should be conducted to check their tightness. (6) Before each ignition, prepare a torch in advance, light it, place it in front of the gas outlet, and then turn on the gas valve. (7) If it is observed that the flame from the furnace heating stove is leaking outward, the cause should be identified promptly, and heating should be stopped if necessary. (8) When it is found that the pipes and hoses of the measuring instruments have come loose, the gas valve should be closed immediately for repair. (9) When using gas for oven heating, the condensate should be drained regularly. (10) A certain number of gas masks should be prepared, and personnel in charge of heating ovens at all levels should know how to use them and be able to operate them skillfully. (11) If operators experience symptoms of poisoning such as headache or nausea, they should immediately go to a place with fresh air; if necessary, they should seek medical treatment at a hospital. (12) When dealing with faults in gas equipment or replacing components, such as orifice plates or valves, at least two persons must be present when conducting a torch test. (13) During the complete shutdown and restart of the furnace, all installation work and other activities carried out near the stove or coal gas pipelines must be halted. (14) Formulate safety technical regulations based on the characteristics of the work and the conditions of the position. (15) When cleaning coal gas pipelines, steam should be used first for purging to remove any remaining coal gas through the vent pipes, while other debris can be removed through the condensate discharge pipes. When delivering gas, steam must first be introduced and released at the vent pipe, after which the gas is used to displace the steam. (16) Safety regulations for working with gas must be strictly followed when operating in gas areas. III. Precautions for safe operation of furnace drying using liquid fuel (1) After installation, the oil tank should be tested with water or air; the pressure testing must be carried out in accordance with relevant requirements. For a hydrostatic test, it is considered successful if there are no leaks after 20 minutes of filling with water. (2) The oil pump has passed the trial run, with a satisfactory leakage rate; the pressure gauge and grounding wires are all present and in good working condition. (3) The test pressure for oil pipes is generally 1.25 to 1.5 times the working pressure. (4) The oil pipeline should maintain a certain distance from high-voltage wires, flammable and explosive pipelines, and areas with high temperatures. (5) When the oil pump is operating normally, prevent the oil tank from running empty. (6) The quality of the oil used for combustion must meet the requirements, especially with regard to the amount of moisture and impurities it contains. Excessive moisture can easily cause the combustion flame to be interrupted, and may even lead to an explosion ； Excessive impurities can easily clog the nozzle. (7) The temperature of the oil during preheating should not be too high; it generally should not exceed 90°C, and boiling must be strictly prevented. (8) An appropriate air-fuel ratio should be selected to ensure complete combustion. (9) In the event of an accident with the fuel equipment, such as oil leaking from the tank or leaks at pipelines and flanges, it must be addressed promptly. (10) The oil tank should not be filled to capacity; it must be properly grounded, with the grounding resistance generally required to be no more than 5–10Ω. (11) In winter, attention must be paid to preventing freezing and condensation in pipelines and valves. When freezing or condensation occurs, it is prohibited to use open flames for treatment; instead, steam or other safe measures must be employed. (12) When performing open-flame operations on fuel equipment and pipelines, the relevant firework procedures must be strictly followed, and corresponding safety measures must also be taken, such as using steam for purging, flushing with cold water, ensuring proper ventilation, and covering the area with fire-resistant materials. Work involving open flames may be carried out only after confirming that there is no risk of combustion or explosion, and a dedicated person must be present to supervise such work.