To learn R290 refrigerant related information
R290 refrigerant is a new type of environmentally friendly refrigerant, mainly used in central air conditioners, heat pump air conditioners, household air conditioners, and other small refrigeration equipment.
R290 refrigerant (propane), also known as propane, has excellent thermal properties and is low-priced. Moreover, R290 refrigerant is compatible with ordinary lubricants and mechanical structural materials. ODP=0, GWP is very small, does not require synthesis, and does not change the content of natural hydrocarbons, has no direct impact on the greenhouse effect.
Propane (r290 refrigerant) has a large cooling capacity per unit volume and is suitable for small rotary compressors. The main physical properties of propane are very similar to R22. The R22 system can be used without modifying the original machine and production line. Propane can be filled directly, which is a direct substitute. Given the cost of CFC replacement, propane is particularly suitable for developing countries.
1. R290 Refrigerant Properties
At -25°C, the pressure of R290 refrigerant is similar to R22, higher than R134a, and lower than R404A. The standard boiling point of R290 refrigerant is identical to that of R22, and the critical temperature is also close to that of R22. However, the exhaust temperature of R290 refrigerant is lower than that of R22, so the pressure of R290 refrigerant is lower than that of R22. In other words, the suction temperature of R290 refrigerant can be higher, and the evaporation temperature can be lower.
At a condensation temperature of 45°C, a suction temperature of 32°C, and no subcooling, the volumetric cooling capacity of R290 refrigerant is similar to that of R22 and is 1.5 times that of R 134a. It is 2.5 to 3 times that of R600a, which means that for a household refrigerator with the same cooling capacity, the structure size of the R290 refrigerant refrigerator refrigeration system is smaller, and the overall space occupied by the refrigerator is reduced.
2. R290 Refrigerant System Performance
At an evaporation temperature of -25°C, a condensation temperature of 45°C, no subcooling, and high superheat, the theoretical COP values of R290 refrigerant, R600a, and R134a are higher than those of R22; at low superheat, the theoretical COP values of R290 refrigerant, R600a, and R134a are Lower than R22.
The COP values of R290 refrigerant and R134a are similar. Just like R134a, R404A, and R600a, suction superheat is very important to the performance of the R290 refrigerant refrigeration system, which can improve the COP of the refrigeration system, while R22 has little effect. For the R290 refrigerant refrigerator refrigeration system, because R290 refrigerant has a high hot steam specific heat, it can have a superheat temperature of 20°C to 32°C, increasing the COP of the r290 refrigerant refrigerator.
3. R290 Refrigerant Safety Performance
The disadvantage of R290 refrigerant as a refrigerant is the flammability of R290 refrigerant. The compressor, condenser, evaporator, pipeline, and other refrigeration system components may cause working fluid leakage, and the thermostat, compressor relay, lighting, and Electronic components such as defrost buttons can be ignition sources. Therefore, the maximum filling capacity of R290 refrigerant in the refrigerator should be controlled at around 150g.
The refrigeration system and control components should be installed in different spaces to ensure safe operation. Install a protector and flame retardant relay on the compressor. Ventilate to avoid local concentration accumulation, and often use gas sensors to detect areas prone to leaks. The R290 refrigerant refrigeration system should be closed and strictly tested for leaks before filling with refrigerant.
Health hazards: Propane (R290 refrigerant) has simple asphyxiation and anesthetic effects. Brief exposure to propane with a concentration of 1% does not cause abnormal symptoms; exposure to propane with a concentration of less than 10% only causes mild dizziness; exposure to high-concentration propane can cause anesthesia and loss of consciousness; exposure to extremely high-concentration propane can cause May to cause suffocation.
In acute poisoning, symptoms such as dizziness, headache, excitement or drowsiness, nausea, vomiting, and slow pulse may occur; severe cases may include sudden collapse, urinary incontinence, loss of consciousness, and even respiratory arrest. It can cause frostbite on the skin. People who are exposed to low-concentration propane for a long time may develop symptoms such as headache, dizziness, poor sleep, fatigue, emotional instability, and autonomic nerve dysfunction.
Environmental hazards: It harms the environment and can cause pollution to water bodies, soil, and atmosphere.
Fire and explosion hazard: R290 refrigerant is flammable and narcotic.
First aid measures: Inhalation: Leave the scene quickly to fresh air; keep the respiratory tract open; if breathing is difficult, give oxygen; if breathing stops, perform artificial respiration immediately; seek medical attention.
Accidental leakage measures
Quickly evacuate personnel in the leaked contaminated area to a place upwind and isolate them until the gas dissipates and cuts off the source of the fire. Emergency responders should wear self-contained breathing apparatus and anti-static fire protection clothing. Cut off the air source, dilute and dissolve with spray water, exhaust (indoors), or forcefully ventilate (outdoors).
Use an explosion-proof exhaust fan to send the leaked air to an open area, or install appropriate nozzles to burn it. You can also move leaky containers to an open area and pay attention to ventilation. Leaking containers cannot be reused and must undergo technical treatment to remove any remaining gas.
- Engineering control: The production process is airtight and fully ventilated to provide good natural ventilation.
- Respiratory system protection: Generally, no special protection is required. A self-priming filter gas mask (half mask) should be worn in particular circumstances.
- Eye protection: Generally, no special protection is required. Safety glasses can be worn when exposed to high concentrations.
- Body protection: Wear anti-static overalls.
- Hand protection: Wear general work protective gloves.
- Others: Smoking is strictly prohibited at the work site; avoid long-term repeated contact; when working in tanks, restricted spaces, or other high-concentration areas, someone must supervise.
R290 refrigerant main uses
- The most extensive use of R290 refrigerant is to make liquefied petroleum gas together with butane, mainly as fuel.
- Propane (R290 refrigerant) is an essential raw material for cracking to produce ethylene.
- The technology of catalytic dehydrogenation of R290 refrigerant to propylene has been industrialized.
- R290 refrigerant gas phase nitrification produces mixed nitro compounds: 1-nitropropane and 2-nitropropane, nitroethane and nitromethane. Nitropropane is a suitable solvent for vinyl and epoxy resins. Nitromethane is used as a racing fuel additive.
- R290 refrigerant can be oxidized to produce propylene oxide, with methanol, formaldehyde, acetaldehyde, and acetic acid as by-products. However, the separation is very troublesome and has yet to be popularized.
- Widely used refrigerant in refining, chemical, and natural gas processing operations.
- Used as a deasphalting solvent for lubricating oil fractions. Asphalt is insoluble in liquid R290 refrigerant. When extracted with R290, the asphalt is removed as an extraction residue, and then the R290 refrigerant is evaporated from the asphalt-removed fraction to leave the lubrication.
- Dewaxing solvent: Almost insoluble in liquefied R290 refrigerant. When liquid R290 refrigerant evaporates, it can obtain a heat of evaporation of approximately 418680kJ/kg. So, utilizing these two characteristics, some propane vaporizes from the lubricating oil propane solution. The generated low temperature precipitates the wax in the raw oil, which is dewaxed by the self-cooling method.
- Chlorination of R290 refrigerant can produce perchloroethylene and carbon tetrachloride.
- A new method for producing acrylonitrile from R290 refrigerant has been developed.
R290 Storage and Transportation
Closed operation, comprehensive ventilation, and good natural ventilation conditions are provided; operators must undergo special training and strictly abide by operating procedures; operators wear filter gas masks (half masks) and anti-static overalls; stay away from fire and heat sources, and are strictly prohibited in the workplace Smoking; use explosion-proof ventilation systems and equipment; prevent gas from leaking into the workplace air; avoid contact with oxidants and halogens; during transportation, cylinders, and containers must be grounded and bridged to avoid the generation of static electricity; load and unload with care when handling, to prevent damage to cylinders and accessories; equipped with corresponding varieties and quantities of fire-fighting equipment and leakage emergency treatment equipment.
Store in a cool, ventilated warehouse; keep away from fire and heat sources; the warehouse temperature should not exceed 30°C; should be stored separately from oxidants and halogens, and avoid mixed storage; use explosion-proof lighting and ventilation facilities; prohibit the use of mechanical equipment and tools that are prone to sparks; The storage area should be equipped with leakage emergency treatment equipment; after compression, it should be stored in a liquid state in a cylinder.
- When transporting by railway, the use of pressure-resistant liquefied gas enterprises’ own tank trucks is limited to shipment, and approval from relevant departments is required before shipment: cylinders containing liquefied petroleum gas (i.e., petroleum gas) are prohibited from being transported by rail.
- When transporting steel cylinders, they must wear the safety cap on the cylinder; cylinders are generally placed flat, and the bottle mouths should face the same direction and cannot cross; the height of the cylinder should not exceed the vehicle’s guardrail, and should be secured with triangular wooden pads to prevent rolling.
- When transporting, the transport vehicle should Equipped with corresponding varieties and quantities of fire-fighting equipment; the exhaust pipe of the car transporting this item must be equipped with a fire arresting device, and it is prohibited to use mechanical equipment and tools that are prone to sparks for loading and unloading; it is strictly forbidden to mix and transport it with oxidants, halogens, etc.; it should be transported in the morning and evening in summer, to prevent sun exposure.
- When in transit, keep away from fire and heat sources; when transporting by road, follow the prescribed route and do not stay in residential areas and densely populated areas; when transporting by rail, it is prohibited to slip away.
R290 refrigerant (propane) has excellent thermal properties, low price, large cooling capacity per unit volume, small size, and physical properties similar to R22, making it a direct substitute. Taking corresponding safety protection measures has good application prospects for environmental protection and energy conservation.