1. Gas quality issues
Purity reduction:
The lubricating oil inside the compressor may mix with nitrogen gas. For example, in a piston compressor, lubricating oil is needed between the piston and the cylinder wall to reduce friction and seal. If the seal is not good, the lubricating oil will be discharged with nitrogen gas, thereby reducing the purity of nitrogen gas. In addition, if there is no good filtering device at the inlet of the compressor, external impurities such as dust, moisture, etc. will also enter the compression system, polluting the nitrogen gas.
For industries that require extremely high purity of nitrogen, such as electronic chip manufacturing, even a slight decrease in purity may affect product quality. For example, in semiconductor lithography processes, insufficient purity of nitrogen gas may lead to a decrease in the performance of photoresist, affecting the accuracy and performance of chips.
Increase in moisture content:
If the nitrogen gas is not sufficiently dried before compression, or if there is a problem with the cooling system during compression, it can cause the condensation of moisture in the nitrogen gas. For example, when the temperature of compressed nitrogen gas decreases, the water vapor inside will reach the dew point and liquefy. These liquid waters may corrode the internal components of the compressor and also reduce the quality of nitrogen gas.
In chemical production, excessive moisture may react with certain chemicals, affecting the normal progress of chemical reactions. For example, in the synthesis of ammonia, water reacts with the catalyst, reducing its activity.
2. Equipment operation issues
Abnormal pressure:
Damaged exhaust or intake valves of the compressor may cause abnormal pressure. If the exhaust valve cannot be opened normally, it will cause the pressure inside the cylinder to be too high, posing a risk of explosion; If the intake valve cannot be closed properly, it will cause the pressure inside the cylinder to fail to meet the design requirements, affecting the compression efficiency of nitrogen gas.
In addition, pipeline blockage or leakage can also cause pressure changes. Pipeline blockage will increase exhaust resistance, leading to an increase in pressure; Pipeline leaks can cause a decrease in pressure, and the leaked nitrogen may also pose a safety hazard, as nitrogen can lower the oxygen content in the surrounding environment, leading to suffocation of personnel.
High temperature:
The compression process is an adiabatic process, and when a gas is compressed, its internal energy increases and its temperature rises. If the cooling system malfunctions, such as damage to the cooling water pump, blockage of the air-cooled radiator, etc., and cannot take away heat in a timely manner, it will cause the temperature of the compressor to be too high. Excessive temperature not only affects the performance and lifespan of the compressor, but may also cause chemical reactions in nitrogen gas.
For example, at high temperatures, certain impurities in nitrogen may react chemically with the materials inside the compressor, damaging the equipment. Meanwhile, high temperatures can also degrade the performance of lubricating oil and exacerbate equipment wear.
Equipment vibration and noise:
Unbalanced operation of the compressor can cause vibration and noise. For example, uneven wear of the piston and looseness of the crankshaft connecting rod mechanism in a piston compressor can cause vibration. Vibration not only affects the stability and service life of the compressor itself, but may also cause loose connecting pipes and leakage.
Excessive noise can pose a threat to the health of operators and may also violate workplace noise regulations. For example, in some factory workshops with strict noise control requirements, compressors with excessively high noise levels may not function properly.
3. Safety issues
Risk of suffocation:
Nitrogen is a suffocating gas, and if there is a leak during compression, it will reduce the oxygen content in the surrounding environment. If personnel stay in a low oxygen environment, they may experience symptoms such as dizziness, nausea, and difficulty breathing, which can lead to suffocation and death in severe cases.
Especially in enclosed or poorly ventilated spaces, the risk of nitrogen leakage is greater. For example, in an underground compressor room, if there is no good ventilation system, nitrogen leakage can easily cause casualties.
Explosion risk:
Although nitrogen itself is an inert gas, if flammable and explosive gases such as hydrogen and oxygen are mixed inside the compressor, an explosion may occur under certain conditions (such as high pressure, high temperature, etc.).
In addition, if the electrical equipment of the compressor does not meet explosion-proof requirements, it may also cause explosions in environments with flammable gases or dust. For example, in the production workshop of a chemical enterprise, there may be a small amount of combustible gas in the surrounding air, and the electrical equipment of the compressor must adopt explosion-proof design.
Processing method
1. Methods for handling gas quality issues
Handling of purity reduction issue
Preventing the mixing of lubricating oil: For compressors that are prone to lubricating oil leakage (such as piston compressors), oil-free lubrication technology can be used, such as using self-lubricating materials to make piston rings and packing. At the same time, regularly inspect the seals of the compressor, and replace them promptly if wear or damage is found. Install an efficient oil separator at the outlet of the compressor to separate the lubricating oil mixed with nitrogen and ensure the purity of nitrogen.
Impurity filtration: Install multi-stage filters at the compressor inlet, including coarse, medium, and high-efficiency filters, to remove impurities such as dust and particulate matter. For application scenarios that require extremely high purity, such as the electronics industry, adsorption towers can also be installed at the inlet to remove trace organic matter, moisture, and other impurity gases from nitrogen using adsorbents such as activated carbon and molecular sieves. And regular replacement of filters and adsorbents is necessary to ensure filtration and adsorption efficiency.
Solution to the issue of increased moisture content
Drying treatment: Before compression, the nitrogen gas is thoroughly dried using methods such as freeze-drying and adsorption drying. Freeze drying is the process of separating water vapor into liquid water by reducing the temperature of nitrogen gas; Adsorption drying is the use of desiccants (such as silica gel, alumina, etc.) to adsorb moisture from nitrogen gas. During the compression process, ensure the normal operation of the cooling system to prevent water vapor from condensing again during the cooling process of the compressed high-temperature gas.
Drainage measures: Install drainage valves at the lowest point of the compressor's storage tank and pipeline, and regularly discharge accumulated liquid water. For large compression systems, automatic drainage devices can be installed to automatically drain water based on liquid level or time intervals. At the same time, record and monitor the drainage situation to promptly detect any abnormal changes in moisture content.
2. Methods for handling equipment operation issues
Handling of abnormal pressure issues
Valve inspection and maintenance: Regularly inspect the intake and exhaust valves of the compressor, and determine whether the valves are working properly through pressure testing, listening to sound, and other methods. If the valve is found to be damaged, it should be replaced in a timely manner. For the sealing surface of the valve, grinding repair can be carried out to ensure the sealing performance of the valve.
Pipeline inspection and maintenance: Regularly inspect pipelines, including visual inspection (for signs of cracks, corrosion, etc.) and pressure testing. For blocked pipelines, chemical cleaning (for internal scaling, etc.) or mechanical dredging (such as using pipeline dredging tools) can be used for cleaning. For leaking pipelines, one can first locate the leak point by applying soapy water or other methods, and then replace the seals or damaged parts of the pipeline.
Handling of High Temperature Issues
Cooling system maintenance: Regularly inspect various components of the cooling system, such as water pumps, radiators, water pipes, etc. in the water-cooled system, and fans and radiators in the air-cooled system. Ensure the normal operation of the water pump, no blockage or leakage in the water pipes, normal rotation of the fan, and no dust accumulation in the radiator. For the water cooling system, it is also necessary to regularly check the quality of the cooling water to prevent scaling and corrosion.
Temperature monitoring and control: Install temperature sensors to monitor the temperature of key parts of the compressor, such as cylinders and exhaust ports. When the temperature approaches or exceeds the set safety threshold, adjust the operating parameters of the compressor through the control system (such as reducing speed, decreasing intake air volume, etc.), or initiate emergency cooling measures (such as increasing cooling water volume).
Handling of equipment vibration and noise issues
Balance adjustment and component repair: For compressors that cause vibration due to unbalanced operation, such as piston compressors, check the wear of components such as pistons, crankshafts, and connecting rods. For pistons with uneven wear, replace or repair them, readjust the assembly accuracy of the crankshaft and connecting rod, and ensure the balance of all components. At the same time, check the fixing of the anchor bolts and connecting pipes of the compressor, and tighten them in a timely manner if they are loose.
Shock absorption and noise reduction measures: Install shock pads or shock absorbers on the base of the compressor to reduce the transmission of vibration to the ground and surrounding environment. For noise problems, sound insulation covers can be set around the compressor, and sound absorption materials (such as sound absorption cotton, foam plastic, etc.) can be used to reduce noise. At the same time, install mufflers at the inlet and outlet of the compressor to reduce airflow noise.
3. Methods for handling security issues
Prevention and treatment of suffocation risk
Leak detection and ventilation measures: Install nitrogen leak detection devices, such as oxygen content monitors, nitrogen concentration detectors, etc., for real-time monitoring in the compressor room and areas where nitrogen leaks may occur. Once a decrease in oxygen content or an abnormal increase in nitrogen concentration is detected, an alarm will be immediately issued. Ensure good ventilation in the workplace. For enclosed compressor rooms, sufficient ventilation equipment such as exhaust fans should be installed to replenish fresh air in a timely manner.
Personnel training and emergency measures: Train operators on the risk of suffocation, so that they understand the dangers of nitrogen and the correct operating methods. Develop emergency rescue plans, including measures for first aid (such as using oxygen respirators for first aid) and evacuating personnel in the event of suffocation accidents. Regularly conduct emergency drills to improve personnel's emergency response capabilities.
Explosion risk prevention and treatment
Gas monitoring and explosion-proof design: Install a gas monitoring system to monitor the gas composition around the compressor in real time, preventing flammable and explosive gases from mixing into nitrogen gas. For the electrical equipment of the compressor, explosion-proof design should be adopted, such as using explosion-proof motors, explosion-proof switches, etc., and it is necessary to ensure good grounding of the electrical equipment to prevent static electricity accumulation from causing explosions.
Safety operating procedures and pressure control: Establish strict safety operating procedures and prohibit operations that may generate sparks or open flames near the compressor. Install a pressure safety valve on the compressor. When the pressure exceeds the set value, the safety valve automatically opens to release gas and prevent explosions caused by excessive pressure. At the same time, regular inspections and maintenance should be carried out on the pressure control system to ensure its normal operation.
