Keywords: compressed natural gas (CNG) vehicles; refueling stations; development prospects; countermeasures
At present, some of China's major cities, automobile emissions are the main source of urban air pollution, therefore, the development of clean energy vehicles has become a choice that can not be delayed. Compressed natural gas vehicles (CNG) with its low energy consumption, pollutant emissions by the countries welcome, is internationally recognized as the most ideal alternative energy vehicle. The development of natural gas vehicles is of great significance in solving environmental and energy problems.
I. Development of Natural Gas Vehicles
l. Overview of the Development of Natural Gas Vehicles in Foreign Countries
In order to protect the environment and reduce pollution, many governments have enacted a series of laws and regulations and introduced a number of incentives to promote the development of gas vehicles, such as the development of more stringent vehicle emission standards, in the supply of natural gas, automobile purchase taxes and fees, the supply of equipment, the construction of filling stations, etc. to give financial and tax incentives. In the United States, the United States is the only country where gas vehicles have been used for a long time.
The U.S. federal government enacted the Energy Policy Act in 1992, which makes detailed provisions for tax reductions and exemptions on the purchase or modification of alternative-fueled vehicles and the construction of refueling stations, and at the same time enacted a policy of tax reductions for the use of natural gas and exempting natural gas companies from sales tax on automotive fuels. More than 40 states have formulated their own state policies and measures on mandating and encouraging the use of CNG and other clean fuel vehicles in accordance with the policies and laws of the federal government, promoting the development of CNG vehicles and the construction of refueling stations. At present, more than 40 countries around the world have gas vehicles, mainly in Italy, New Zealand, Argentina, Brazil and other countries rich in natural gas resources and the United States, Japan and other countries with strict environmental regulations.
2, the development of natural gas vehicles in China
In the mid-1980s, China introduced some CNG filling station equipment, the establishment of China's first CNG filling station in Sichuan; in 1993, the China National Petroleum Corporation system to introduce the relevant foreign technology and in 1996, the filling station equipment and car conversion parts to introduce technology localization, technical standards, standardization. 1999, the national clean car in the country, the introduction of cleaner vehicles. In 1999, the National Leading Group of Clean Vehicle Action Coordination was set up, which initiated the promotion and application of clean energy in 12 pilot cities and regions, such as Beijing, Tianjin, Shanghai, Xi'an, Shenzhen, etc., and achieved unprecedented results in the promotion and application of CNG vehicles and the construction of gas filling stations. According to the statistics of the relevant departments, as of 2004, some areas of China **** there are more than 200,000 natural gas vehicles and more than 700 refueling stations.
Second, natural gas vehicles (CNG) and other fuels, environmental and economic benefits of comparison
Compressed natural gas vehicles:
Natural gas compressed to 20MPa in the car with compressed natural gas cylinders, through the regulator to supply the internal combustion engine.
CNG as automobile fuel has the following advantages compared with gasoline:
l. Reduce pollution and improve the atmospheric environment: natural gas is a clean energy with high calorific value, high efficiency, low pollution and other characteristics, combustion is more complete, not easy to build up carbon, CO, NOx, and particle emissions are lower than the gasoline, the exhaust pollution is significantly reduced. Motor vehicle exhaust is one of the main sources of urban air pollution, of which the main harmful components are carbon monoxide (C0), hydrocarbons (HC), nitric oxide (N0) and nitrogen dioxide (NO2) and so on. According to relevant information, the use of natural gas as automobile fuel and gasoline as fuel compared to reduce emissions of 90% CO, 90% S02, 72% HC, 39% NOx, 24% CO2, no dust emissions, to improve the urban environment has a significant role. A comparison of typical diesel engine emissions with gasoline and natural gas engine emissions is shown in Table l.
2, CNG vehicles have a high degree of safety
Compared with gasoline, compressed natural gas is a relatively safe fuel.
(1) natural gas explosion lower limit of 5%, higher than gasoline (explosion lower limit of l%), methane ignition point of 645 ℃, higher than the ignition point of gasoline 218 ℃, compared to not easy to ignite. Methane density is low, the relative density of 0.55 or so, the leakage of gas will soon be distributed in the air, in the natural environment, it is difficult to form the conditions of ignition in case of fire, once the compressed natural gas leaks from the tanks or pipelines, the leakage point will be immediately formed around the cryogenic zone, so that the natural gas combustion difficulties. Therefore, CNG is a fairly safe automotive fuel. Comparison of the fuel characteristics of natural gas and gasoline in Table 2
(2) natural gas automobile cylinders are high-pressure containers
(20MPa), its materials and manufacturing, inspection and testing in various countries have strict regulations to control, in our country there is a "standard for compressed natural gas cylinders for automobiles)) (GBl7258-1998).
Cylinders installed with explosion-proof facilities, pressure reducers, valves and other equipment, high density standards, gas supply system is safe and reliable, will not be caused by car collision or overturning fire or explosion, and gasoline automobile tanks Department of non-pressure vessel, easy to explode after fire.
3, is conducive to easing the tension between energy supply and demand.
China's economy is in a phase of rapid development, the number of cars to more than 1 million / annual rate of increase in demand for gasoline resources, China needs to import a large amount of crude oil, refined oil and LPG every year. gas vehicles can optimize
automotive fuel supply structure, change the automotive fuel only gasoline, diesel fuel pattern, not only to alleviate the gasoline supply problems It also meets the needs of the development of the transportation industry.
4, can extend the engine life. Natural gas is easy to diffuse, in a gaseous state into the engine, in the engine is easy to mix evenly with the air, combustion is more complete, clean; can improve the efficiency of thermal cycling, speed up the combustion rate, make full use of combustion heat; at the same time, CNG high octane, good anti-violence performance, the use of the use of anti-violence agent does not need to be added, will not dilute the lubricating oil, thus reducing the wear and tear of parts in the engine cylinders, so that the engine life and lubricating oil use period increased dramatically. The life span of the engine and lubricating oil is greatly increased. All of these will reduce the maintenance and running costs of the car, thus improving the economy of automobile use. 5、Higher economic efficiency. At present, domestic gasoline prices continue to rise, the price system has been aligned with the world, the use of CNG vehicles will be able to save nearly 40% of the fuel costs, see Table 3.
Three, the development prospects of CNG vehicles
CNG vehicles and refueling stations have a broad development prospects, mainly in the following aspects:
l, the rapid growth of automobile ownership, oil resources and the environmental protection of the serious situation, decided to develop natural gas vehicles become an important way to solve the energy problem and environmental issues.
2, "Eleventh Five-Year" period, the new clean energy vehicles have been included in the "national science and technology development in the medium and long term plan", the state will continue to organize the implementation of major scientific and technological projects involving a variety of clean energy vehicles, focusing on support for the vehicle, including natural gas vehicles, parts and components, and other key technologies, which will further promote the natural gas This will further promote the development of natural gas vehicles.
3, China's large-scale development of natural gas resources and pipeline construction to accelerate the pace of development of CNG and gas stations possible. According to China's natural gas utilization planning, in the past decade, "West-East Gas Pipeline", "Shaanxi-Beijing second line" and a large number of gas pipelines and city gas pipelines along the route have been completed, China's large-scale use of natural gas infrastructure gradually improved, natural gas refueling stations will gradually form a network. network.
4, the development of CNG vehicles have a stable gas source to ensure that, in Tianjin, for example, Tianjin has established a perfect natural gas transmission and distribution system, by the Shaanxi, Dagang, North China and other oil fields to supply gas to Tianjin, the annual supply of gas in 2005, nearly 600 million m3, 2006 is expected to reach 800 million m3, the length of the network of 6,894km, of which, the high-pressure pipeline 591km, for the "Eleventh Five-Year Plan". During the "Eleventh Five-Year Plan" period, Tianjin will vigorously develop CNG vehicles and build gas filling stations on a large scale to provide a guarantee.
Four, CNG vehicles and refueling station development countermeasures to discuss
In order to accelerate the development of clean vehicles fueled by natural gas, the following recommendations:
1, the government to introduce incentives and supportive policies: the development experience of countries around the world has shown that the government's support is a necessary condition for accelerating the development of its economic policy is an important factor affecting the development of its should be in the legal aspects to be Guarantee, in the gas car production, modification, parts and components production, gas station construction, gas car purchase and use, maintenance and other aspects of the development of price, tax, investment, subsidies and other aspects of supporting preferential policies. Gas price is an important factor affecting the development of gas vehicles, only gas prices and gasoline prices to form a large enough difference in price, the development of gas vehicles have the economic basis and driving force.
2, strengthen leadership, the implementation of unified management. The development of CNG vehicles must build high-quality, convenient gas filling stations, need the support of planning, public security, fire, labor, technical supervision and other departments.
3, in municipal planning, filling stations and gas stations should be considered in an integrated manner, rational layout, coordinated development. Try to use the existing land resources, under the premise of ensuring environmental safety, the construction of oil and gas stations.
4, follow the principle of synchronous development of CNG vehicles and gas stations, only under the conditions of gas stations into a network, CNG vehicles can really develop. At the same time only CNG car scale to a certain number of gas stations can operate normally and realize profits.
5, strict legal system: the development of strict automobile emissions regulations, and effectively achieve the standard vehicles resolutely not to be on the road, the qualification of CNG vehicle refitting plant to carry out a rigorous review of the certification. First of all, the city should be urban buses, rental cars as the focus of the development of CNG vehicles, to put an end to the phenomenon of part of the bus smoke pollution of the environment.
6, increase publicity. At present, the natural gas car is still in its infancy, the public on its environmental protection, safety, economy, reliability is not fully understand, so, to carry out a wide range of social publicity, and strive to improve people's understanding of the harmful effects of automobile exhaust, so that people understand that the CNG is a clean, safe, economic vehicle fuel, so that the development of natural gas vehicles to get the recognition of all aspects of society and support.
CNG vehicles will become a new field of natural gas market development and application due to its significant economic and social benefits. Under the situation that environmental protection is paid more and more attention to, with the development of natural gas resources and the broadening of the application field, this move will be a reliable guarantee to reduce the pressure of environmental pollution, alleviate the shortage of oil and realize sustainable development.
Abstract: This paper describes the development of compressed natural gas vehicles (CNG) on environmental protection of low-pollution, security, economic and CNG cars and sustainable development. security, economic and CNG cars and filling stations and prospects for the development of countermeasures.
Key words: compressed natural gas vehicles; stations; development prospects; Countermeasures
At present, China's major cities is a urban vehicle emissions a major source of air pollution, therefore, the development of cleaner vehicles and filling stations is a major challenge. pollution, therefore, the development of clean energy vehicles have become the choice of the delay. Compressed natural gas vehicles (CNG) in their low energy consumption and emissions by all countries small and medium-sized vehicles have become a major source of air pollution. Compressed natural gas vehicles (CNG) in their low energy consumption and emissions by all countries small and welcoming, is recognized internationally as the best alternative energy vehicle. development of natural gas vehicle to address the environmental issues and energy issues are of great significance.
First, the development of natural gas vehicle
l, development of foreign natural gas vehicle
Reduce pollution to protect the environment, many countries have issued a series of government regulations and the introduction of a number of incentive policies to promote the development of gas vehicle, such as the development of more stringent vehicle emission standards, and the introduction of a number of incentive policies to promote the development of gas vehicle. development of more stringent vehicle emission standards, in the natural gas supply, car purchase taxes and fees, equipment supply, gas station construction grant funds, tax incentives
In 1992 the U.S. federal government enacted the "Energy Policy Act," or modified for the purchase of alternative fuel vehicles and the construction of stations. In 1992 the U.S. federal government enacted the "Energy Policy Act," or modified for the purchase of alternative fuel vehicles and the construction of stations in detail the provisions of the tax relief, but also enacted a tax cut that the use of natural gas There are more than 40 states in accordance with the policy of the federal government, law, drawn up on the mandatory fuel sales tax. There are more than 40 states in accordance with the policy of the federal government, law, drawn up on the mandatory state and encourage the use of clean fuel CNG vehicles, such as policies and measures to promote the CNG filling station development and construction of motor vehicles. At present, more than 40 countries around the world have a gas car, mainly in the rich natural gas resources in Italy, New Zealand, Argentina and other countries. At present, more than 40 countries around the world have a gas car, mainly in the rich natural gas resources in Italy, New Zealand, Argentina, Brazil and other countries and stricter environmental regulations the United States, Japan and other countries. countries.
2, China's Natural Gas Vehicle Development
80 In the mid-20th century, the introduction of some of our CNG filling station equipment, set up in Sichuan's Sichuan Province, was a major step forward. In the mid-20th century, the introduction of some of our CNG filling station equipment, set up in Sichuan's first CNG filling stations in China; in 1993 the China National Petroleum Corporation on the introduction of foreign technology systems in 1996 installations and will be filling stations modified car parts made of the introduction of technology, standardization of 1999 National Clean Automobile Action Coordination Leading Group was established to start the Beijing, Tianjin, Shanghai, Xi'an , Shenzhen and other cities in 12 pilot projects. The National Clean Automobile Action Coordination Leading Group was established to start the Beijing, Tianjin, Shanghai, Xi'an, Shenzhen and other cities in 12 pilot areas to promote the application of clean energy in the popularization and application of CNG vehicles and filling stations has made an unprecedented building results. According to relevant statistics, as of 2004 there were some areas of China's natural gas vehicle more than 20 million vehicles, more than 20% of the total number of vehicles, and more than 50% of the total number of vehicles in China's natural gas vehicle fleet. According to relevant statistics, as of 2004 there were some areas of China's natural gas vehicle more than 20 million vehicles, more than 700 filling stations Block.
Second, natural gas vehicle (CNG) fuel and other environmental and economic benefits compared
Compressed natural gas vehicles:
20MPa compressed natural gas in the car to compressed natural gas cylinders in use by the supply of internal combustion engine after the pressure reducer.
To CNG fuel for vehicles compared with gasoline has the following advantages:
l, reduce pollution and improve the atmospheric environment: natural gas is a clean energy, with a high calorific value, high efficiency, pollution, etc., the comparison is totally burned, not carbon deposition, CO, NOx and particulate emissions than gasoline, significantly Motor vehicle exhaust is the major source of urban air pollution, one of which is carbon monoxide harmful ingredients (C0), hydrocarbons (HC), and other harmful substances. hydrocarbons (HC), nitric oxide (N0) and nitrogen dioxide (NO2) and so on. According to the data, the use of gas as a motor fuel and gasoline as fuel can reduce emissions compared to 90% CO, 90% S02, 72% HC, 39% NOx, 24% CO2, non-dust emissions, to improve the urban environment has a significant role in . A typical diesel engine and gasoline engine emissions and gas machine is shown in table l.
2, CNG vehicle for a higher security
Compared with gasoline, compressed natural gas is the best choice.
Compared with gasoline, compressed natural gas is a relatively safe fuel.
(1) natural gas explosion limit is 5% higher than gasoline (lower explosion limit for the l%) high, methane ignition for 645 ℃, ignition than gasoline high 218 ℃, compared to not ignite. Low density of methane, the relative density of about 0.55, resulting in a high density of methane. of about 0.55, resulting in leakage of gas will soon be distributed in the air, in the case of the natural environment it is difficult to form a hot combustion conditions, once the compressed natural gas from the tank or pipe leaks, leak immediately surrounding the formation of low-temperature zone, so that the difficulties of natural gas combustion. Therefore is a fairly safe CNG motor fuel. Natural gas and fuel properties of gasoline is shown in table 2
() 2) Department of natural gas vehicle cylinder pressure vessel
(20MPa), its materials and manufacture and testing in order that all States have strict control, in China there are "compressed natural gas cylinder vehicle standards))) (GBl7258-1998).
Cylinders fitted with explosion-proof facilities, pressure reducer, valves and other equipment, strict standards high, and gas supply system is safe and reliable and will not tip over due to vehicle collision or cause fire or explosion, and the petrol tank of motor vehicles department of non pressure vessels, fire easily after the explosion.
3, will help ease the contradiction between energy supply and demand tension.
China' s economy is in a stage of rapid development. s economy is in a stage of rapid development, the number of vehicles to 1 million / year above the rate of increase of a substantial increase in gasoline
China's economy is in a stage of rapid development, the number of vehicles to 1 million / year above the rate of increase of a substantial increase in gasoline demand of resources, our need to import large quantities of crude oil per year, refined oil and LPG. Optimize the use of gas cars
Motor fuel supply
Motor fuel supply structure has changed only motor fuel gasoline, diesel patterns, not only eased the problem of shortage of petrol and transport services to meet the needs of the development.
4, extend engine life. The spread of natural gas to the gas entering the engine, the engine easily and uniformly mixed air, burning the comparison is totally clean; can be used in a variety of ways, including the use of natural gas, gasoline, diesel, diesel, and so on. The spread of natural gas to the gas entering the engine, the engine easily and uniformly mixed air, burning the comparison is totally clean; can improve the thermal cycle efficiency, speed up the burning speed, full use of combustion heat; CNG octane number at the same time high performance uprising number at the same time high performance uprising, when agents do not need to add the uprising will not dilute the lubricating oil, making the parts inside the engine cylinder greatly reduce wear and tear, so that the engine oil life and increase the use of the period. All of these vehicles will reduce All of these vehicles will reduce maintenance and operating costs, thereby enhancing the economy of the use of vehicles. 5, have a higher economic efficiency. At present, domestic gasoline prices continued to rise, the number of vehicles in the market is increasing. At present, domestic gasoline prices continued to rise, the price system and the world has been the use of CNG vehicle will be able to save nearly 40% of fuel costs, as shown in table 3.
Third, CNG vehicle development prospects
CNG cars and filling stations will have broad prospects for development, mainly in the following aspects:
l, cars of the rapid growth of oil resources and environmental protection, the grim situation, the decision of the
l, cars of the rapid growth of oil resources and environmental protection, the grim situation, the decision of the development of natural gas vehicles as a solution to energy issues and environmental issues an important way.
2, "Eleventh Five-Year" period, a new type of clean energy vehicles have been included in "long-term national science and technology development planning", the state will continue to organize and implement a variety of clean energy vehicles of major scientific and technological projects, the focus of support, including natural gas vehicles, including vehicles, parts, etc., will further promote the development of natural gas vehicle.
3, large-scale development of China's
3, large-scale development of China's natural gas resources and pipeline construction to accelerate the pace of development of CNG and LPG filling stations make it possible. According to China's natural gas use planning, for nearly a decade, "West-East Gas Transmission", "second Shaanxi-Beijing", such as a large number of gas pipeline and gas pipeline along the cities have been developed. and gas pipeline along the cities have built large-scale use of natural gas in China's gradual improvement of infrastructure, natural gas filling stations will gradually form a network.
4, the development of CNG auto gas source with the stability of assurance to Tianjin as an example, at The development of CNG auto gas source with the stability of assurance to Tianjin as an example, at present, Tianjin has established a perfect system of natural gas transmission and distribution, from northern Shaanxi, Dagang, Tianjin, North China Oil Field to supply, gas supply is nearly mid-2005 600 million m3, 2006 was projected to reach 800 million m3, the length of pipe network 6894km, of which high-pressure pipeline 591km, for the "Eleventh Five-Year" period of Tianjin to develop large-scale construction of CNG filling stations car provides
Fourth, CNG cars and filling stations to explore the development of countermeasures
In order to speed up the use of natural gas as a clean fuel vehicle development, the development of CNG filling stations in Tianjin should be strengthened. gas as a clean fuel vehicle development, makes the following recommendations:
1, the Government has introduced policies to encourage and support: the development of all countries in the world experience shows that government support is a necessary condition for accelerated development, the impact of its economic policy is an important factor in the development of clean fuel vehicles. the impact of its economic policy is an important factor in their development should be guaranteed in law, in the gas automobile production, modification , parts and components production, station construction, vehicle purchase and use of gas, maintenance and other aspects of pricing, taxation, investment, subsidies and other aspects of gas automobile production. Gas prices affect gas vehicle development is an important factor, only the gas prices and gasoline prices are not sufficiently high. Only the gas prices and gasoline prices when the difference is large enough to form, gas car before the development of an economic foundation and driving force.
2, strengthen leadership, the implementation of unified management.
The development of CNG vehicles to the construction of high -quality, convenient filling stations, the construction of the new CNG vehicles is an important factor.
The development of CNG vehicles to the construction of high -quality, convenient filling stations, the need for planning, public security, fire safety, labor, technical support supervisor and other
3, in the municipal plan, filling stations and gas stations should be considered co-ordination, rational distribution and coordinated development. To make full use of existing land resources and in ensuring the environmental safety of oil and gas under the premise of building one station.
4, followed by motor cars and CNG filling stations in the simultaneous development of the principles, only in the stations into a At the same time scale of only CNG car to a certain number, the normal operation of filling stations in order to achieve profitability. At the same time scale of only CNG car to a certain number, the normal operation of filling stations in order to achieve profitability.
5, the strict legal system: the development of stringent vehicle emissions regulations, and make sure that standards are not road vehicles are not the same. ensure that standards are not road vehicles are determined not to be on the qualifications of CNG vehicle Modify-Factroy critical examination, certification. First of all, the city should the city bus, taxi, as the focus of the development of CNG vehicle, bus stop some of the phenomenon of black smoke pollution of the environment.
6, step up publicity. At present, natural gas car is still at the initial stage, the public nature of its environmental protection, safety, economy, reliability, and the ability to protect the environment. At present, natural gas car is still at the initial stage, the public nature of its environmental protection, safety, economy, reliability, do not fully understand, so, it is necessary to carry out a wide range of social advocacy, efforts to increase awareness of the dangers. efforts to increase awareness of the dangers of automobile exhaust, to make people aware of CNG is a clean, safe and economical fuel, so that the development of natural gas vehicles have been recognized as the most effective way to promote the development of natural gas vehicles. development of natural gas vehicles have been recognized by all sectors of society and support.
Compressed natural gas vehicles because of its Compressed natural gas vehicles because of its remarkable economic and social benefits the development of the natural gas market will become a new field of applications. more and more importance in the environmental protection situation, along with natural gas resources in the area of the development and application of the widening, which will reduce the environmental pressure is to ease the oil shortage and achieve sustainable development of a reliable guarantee.