Characteristics and Danger of LPG
1, liquefied petroleum gas has the following characteristics
(1) Volatile liquefied petroleum gas at ambient temperature and pressure immediately volatilized into a gas, the volume of sudden expansion of about 250 to 300 times, the rapid spread of spread.
(2) Flammable and explosive liquefied petroleum gas has a low flash point and high danger. When liquefied petroleum gas comes into contact with air, it can be ignited by tiny sparks and has a high combustion value of 2.10 × 104 to 2.90 × 104 Kcal / m3, higher than the natural gas combustion value. The burning rate of liquefied petroleum gas is 0.38 ~ 0.5m / s.
(3) low corrosive liquefied petroleum gas Low sulfur content, generally non-corrosive, but can soften the rubber, so that those greases paint and grease dissolved. So liquefied petroleum gas is used for high-pressure hose.
(4) Micro-toxicity Liquefied petroleum gas in the air is less than 1% in concentration, which is not dangerous to human health. However, long-term exposure to liquefied petroleum gas with high concentration has adverse effects on the nervous system. In the air, liquefied petroleum gas When the gas concentration exceeds 10%, it will suffocate.
(5) Expansion and contraction LPG, like other objects, also has the properties of thermal expansion and contraction. The expansion coefficient of LPG is about 16 times larger than that of water. According to the calculation, the cylinder filled with liquefied petroleum gas, the temperature increased by 1 ℃, the pressure will rise 2 ~ 3Mpa. So, as long as the temperature increased 3 ~ 5 ℃, the internal pressure will exceed the limit of 8Mpa ordinary cylinders. The company is located in:
2, the risk of liquefied petroleum gas
(1) Danger of explosion and fire The lower the flash point of the liquid, the greater the risk of fire. Due to the low flash point of liquefied petroleum gas, it is possible to burn in the event of a fire, neither in winter nor in summer. LPG is a fire hazard level. Liquefied petroleum gas has a lower explosion limit and a large explosion range. In case of ignition, there is a danger of burning and explosion. The explosion speed is 2000-3000 m / s and the flame temperature is as high as 2000 ° C. High heat value of liquefied petroleum gas, liquid low fever value of 11000kcal / kg, gas calorific value of 22000 ~ 26000kcal / m3, is a good fuel. However, in the event of a fire explosion, it can cause serious damage. Because it is heavier than air, it is easy to stagnate and accumulate in the ground space, pits, ditches, sewers and corners and other low-lying place, sometimes not easy to be scattered by the wind, mixed with air to form explosive substances, in case of fire can cause an explosion. Therefore, liquefied petroleum gas should be stored in a well-ventilated place.
(2) Poisoning risk Liquefied petroleum gas (LPG) has the characteristics of micro-toxicity. High-concentration liquefied petroleum gas is inhaled into the body and has an anesthetic effect on the central nervous system of the human being. This can cause unconsciousness and vomiting, and cause suffocation when severe. In addition, LPG combustion requires 25 to 33 times the air, resulting in incomplete combustion of oxygen, will also produce toxic gases such as carbon monoxide.