Resources and application of natural gas for train

Automotive natural gas resources and applications

key words: natural gas, resources, applications

paper Abstract: it is imperative for the automotive industry to develop clean alternative fuels. The promotion and application of clean alternative fuels is an important measure to optimize the energy structure and reduce automotive emissions. Among all kinds of alternative fuels for automobiles, natural gas is an ideal clean fuel. It has the advantages of resources, environmental protection, economy and safety. According to the different forms of natural gas used, natural gas vehicles can be divided into compressed natural gas vehicles (CNGV), liquefied natural gas vehicles (LNGV) and adsorbed natural gas vehicles (ANGV). In recent years, natural gas hydrate resources have also attracted great attention. At present, China has begun to promote the use of CNG vehicles

1 overview of natural gas resources

1.1 natural gas resources

according to the results of the second round of national oil and gas resource evaluation completed in 1994, China's total natural gas resources are 38.04 trillion m3 (excluding coal bed methane), of which 29.9 trillion m3 are onshore and 8.14 trillion m3 are offshore. China's natural gas resources are relatively concentrated, mainly distributed in the central, Western and sea areas, accounting for 30.28%, 28.23% and 21.4% of the total resources respectively; The natural gas resources with burial depth of more than 3500m account for 58.39% of the total; The natural gas resources in Loess Plateau, mountainous and desert areas with relatively poor land geographical conditions are 24.48 trillion m3, accounting for 64% of the total

at present, due to the relatively backward exploration, development and utilization of natural gas in China, by the end of 1999, China's cumulative proved geological reserves of natural gas were only 2.16 trillion m3, but China's proved reserves have great growth potential. According to experts' prediction, from 2001 to 2020, China's proved reserves of natural gas will maintain an average annual growth of about 120billion m3, and may reach a peak in 2015

it is estimated that the ultimate proved natural gas resources in China are 9-12 trillion m3. At present, China has more than 100 billion m3 of remaining recoverable natural gas reserves, which has laid a domestic resource foundation for accelerating the development and utilization of natural gas resources

1.2 natural gas consumption structure

for many years, China's natural gas has been hovering around 2% in the national primary energy output and consumption composition. In 2000, China's natural gas output was 27.73 billion m3, with a per capita natural gas output of about 20m3, which is far behind that of developed countries (such as Britain, with a per capita natural gas output of more than 1300). This is mainly related to factors such as the degree of resource development, lagging infrastructure such as natural gas storage and transportation, and unreasonable composition of natural gas consumption. Table 1 and table 2 respectively show the composition of primary energy consumption and natural gas consumption in China and major countries and regions in the world

Table 1 Composition of primary energy consumption in major countries and regions in the world in 1999

proportion of total national energy consumption

(1million tons of oil equivalent) in consumption (%) Oil, gas, coal, nuclear power, hydropower, the United States

Britain

Russia

India

China

Japan 2204.9

222.4

607.8

276.4

752.6

507.440.04

35.39

20.76

34.29

26.57

51.0125.18

37.10

53.85

7.74

2.56

13.2224.64

16.10

17.98

54.27

67.90

18.038.97

11.15

5.13

1.19

0.54

16.161.17

0.27

2.27

2.50

2.42

1.58 world 8533.640.5724.1924.957.632.66

Table 2 composition of natural gas consumption in China and other regions in the world (%) National and regional power generation industry, chemical raw materials, cities and businesses account for the proportion of energy consumption North America

Western Europe

Eastern Europe

the former Soviet Union

the Middle East

Africa

Japan

Southeast Asia

China 13

17

16

36

32

42

70

38

1534

24

45

44

54

45

29

44

16.84

4

13

4

9

4

1

10

50.839

45

26

16

5

9

-

8

17.427.2

19.4

-

50.9

37.7

16.8

11.2

-

2.1 world average 2

note: the data of China is 1998, and the data of other regions is 1995

it can be seen from table 1 and table 2 that China still takes coal as the main energy at present, and the proportion of natural gas in the composition of primary energy consumption is less than 1/10 of the world average level due to the decline of performance; Moreover, the composition of natural gas consumption in China lags far behind that in other regions. Natural gas in China is mainly used as chemical raw materials, while in foreign countries it is mainly used in the industrial sector, followed by the fields of life and transportation. Therefore, some large and medium-sized cities and areas with relatively developed industry and economy in China have serious air pollution, as shown in Table 3

Table 3 table of air pollution in some cities in the world

population and pollutants Beijing, Shanghai, Guangzhou, Tokyo, London, New York, Paris, Berlin, Milan, Mexico population (10000 people) 1223.41306.6674.12695.9764.01633.2952.3331.7425.11652.2 suspended particles/m--so2/mno2/m

note: according to the statistical data of the World Bank (1995)

1.3 natural gas supply and demand forecast

according to senior experts, direct gating or large cross-section gating can reduce shrinkage, However, the anisotropy is large, the shrinkage along the material flow direction is small, and the shrinkage along the vertical material flow direction is large; On the contrary, when the gate thickness is small, the gate part will condense and harden prematurely, and the plastic in the mold cavity cannot be supplemented in time after shrinkage. Energy experts predict that the annual output of natural gas in China will reach 70billion m3 by 2010 and 100billion m3 by 2020. However, China's demand for natural gas is growing faster. It is expected that the proportion of natural gas in the total demand for energy consumption will increase to 6% in 2010 and 10% in 2020. If estimated based on basic demand, the demand for natural gas will reach 95 billion m3 in 2010 and 203.7 billion m3 in 2020. It can be seen that the supply of self-produced natural gas in China is seriously insufficient. The natural gas gap in China will reach tens of billions of m3 in 2010 and hundreds of billions of m3 in 2020. This gap needs to be filled by importing pipeline natural gas and liquefied natural gas

it is reported that China is currently increasing the exploration and development of domestic natural gas, vigorously promoting the use of natural gas, and actively introducing LNG and pipeline natural gas. According to an official of the Industrial Development Department of the State Planning Commission, China's natural gas imports will mainly come from Russia. China and Russia plan to build a natural gas pipeline with a length of 4000 to 5000 kilometers. The target market for imported natural gas is northeast China and the Bohai Rim region. It is understood that so far, 46 oil and gas fields have been discovered in southern Siberia of Russia, which can supply 30billion m3 of gas to China every year and ensure stable gas supply for 25 to 27 years. In addition, the natural gas resources in the Asia Pacific and the Middle East will form a scale with an annual output of more than 50million tons of LNG in the next few years, which can also be used by China

2 background of the development of natural gas vehicles

cars have brought great convenience to people and made great contributions to the development of human society, but at the same time, they consume a lot of oil resources, emit a lot of harmful gases, and cause great harm to the human living environment. Now the exhaust gas pollution of motor vehicles has become the main source of urban pollution. According to statistics, 50% of the world's oil production is consumed in the transportation sector, and about 30% is used as vehicle fuel; 60-70% of the smoke and more than 50% of the acid rain that cause global environmental pollution come from the transportation industry. Therefore, the problems of automobile energy efficiency, harmful emissions, and the development and utilization of new energy for vehicles have been concerned by governments, experts and the public for nearly 30 years

2.1 the development of natural gas vehicles shows that natural gas vehicles are an important way to achieve the sustainable development of the automotive industry

China's automotive industry has made considerable progress after more than 40 years of construction and development. According to statistics, in recent 10 years, the average growth rate of China's automobile production has remained at about 13%, and the average growth rate of car ownership has remained at about 12%. At present, China's car ownership is more than 16 million, and the annual output is more than 2 million; Especially in Beijing, Shanghai, Guangzhou and other big cities, the number of motor vehicles has increased rapidly at a rate of more than 15% per year. At present, the number of motor vehicles in Beijing has reached 1.5 million, ranking first in all cities in the country. It is predicted that the social ownership of cars in China will reach 26million in 2005 and 40million in 2010

with the rapid growth of car ownership, cars will become the main consumer of oil resources and the main pollution source of the atmospheric environment. Petroleum resources are conventional fuels for automobiles, which have the advantages of high energy density, good safety, convenient storage and transportation, but petroleum resources are limited. At present, the shortage of petroleum fuels in China has been very serious. In 2000, China's net import of petroleum was 69.74 million tons, with a net import rate of 30%. Nearly $20billion was spent. With the current net oil import rate as high as 30%, the impact of the oil crisis on China's economy needs to be paid attention to. It is predicted that the gap between China's energy supply and demand will become larger and larger in the future. In 2010, China's oil supply and demand gap will be more than 100 million tons, accounting for about 1/3 of China's oil demand in 2010. Therefore, the development of energy-saving vehicles and the active use of new coal and natural gas as the power source of vehicles have become a new hot spot in the technological development of the automotive industry all over the world

especially the current violent turbulence in the international crude oil market makes the development and utilization of natural gas more urgent, and the large-scale development and utilization of natural gas will help to fill the gap in China's oil demand and become an important part of China's oil strategic security

2.2 the promotion of natural gas vehicles is an effective measure to solve and improve vehicle emission pollution

the rapid development of modern automobile industry has brought great wealth to the society, but with serious exhaust emission pollution and noise pollution, now vehicle exhaust pollution has become the main source of urban pollution. Table 4 shows the share of traffic exhaust emissions in total air pollution in some countries and domestic cities

Table 4 share rate of vehicle exhaust emissions pollutants (%) in some countries and domestic cities

United States, Japan, Germany, Beijing, Shanghai, Chongqing, Guangzhou co8294 588.8HC5867. NOx.. 3 particles 4 -

from the data in Table 4, almost all three indicators are more than half, and some components have exceeded 90%. These data show that in order to control air pollution in cities, especially large cities, we must first reduce vehicle exhaust pollution

although the number of cars in Beijing is less than that in some large cities abroad, the pollutants emitted by single cars are several times or even more than ten times higher than that of similar foreign cars (it is reported that the HC, CO and NOx emissions of domestic cars are 14.5 times, 11.8 times and 3.3 times that of new cars in the United States in 1992, respectively). NOx and co released by the city's automobile exhaust are becoming more and more serious, and the two pollutants at the intersection of main streets and sidewalks all exceed the standard. See tables 5 and 6 for the NOx emission of various motor vehicles in Beijing in 1997. In addition, the pollutants emitted by cars may also cause photochemical smog, which Beijing is not mining