【正文】 s natural gas resources and pipeline construction to accelerate the pace of development of CNG and LPG filling stations make it possible. According to China39。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 pared Compressed natural gas vehicles: 20MPa pressed natural gas in the car to pressed natural gas cylinders in use by the supply of internal bustion engine after the pressure reducer. To CNG fuel for vehicles pared 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 parison is totally burned, not carbon deposition, CO, NOx and particulate emissions than gasoline, significantly reduced exhaust pollution. Motor vehicle exhaust is the major source of urban air pollution, one of which is carbon monoxide harmful ingredients (C0), 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 pared to 90% CO, 90% S02, 72% HC, 39% NOx, 24% CO2, nondust 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, pressed 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 ℃ , pared to not ignite. Low density of methane, the relative density of about , 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 第 9 頁 bustion conditions, once the pressed natural gas from the tank or pipe leaks, leak immediately surrounding the formation of lowtemperature zone, so that the difficulties of natural gas bustion. 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 pressed natural gas cylinder vehicle standards)) (GBl72581998). Cylinders fitted with explosionproof 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 nonpressure vessels, fire easily after the explosion. 3, will help ease the contradiction between energy supply and demand tension. China39。s Natural Gas Vehicle Development 80 In the mid20th century, the introduction of some of our CNG filling station equipment, set up in Sichuan39。 stations。目前，天然氣汽車尚處于起步階段，社會公眾對它的環(huán)保性，安全性，經(jīng)濟性，可靠性還不充分了解，所以，要進行廣泛的社會宣傳，努力提高人們對汽車尾氣危害性的認識，使人們了解 CNG 是清潔、安全、經(jīng)濟的車用燃料，使發(fā)展天然氣汽車得到社會各方面的認可和支持。同時也只有 CNG 汽車規(guī)模到了一定數(shù)量，加氣站才能正常運轉(zhuǎn)，實現(xiàn)盈利。發(fā)展 CNG 汽車必須建設優(yōu)質(zhì)、便利的加氣站，需要規(guī)劃、公安、消防、勞動 、技監(jiān)等部門的支持。 發(fā)展 CNG 汽車具有穩(wěn)定的氣源保證，以天津為例，目前天津市已建立了完善的天然氣輸配系統(tǒng)，由陜北、大港、華北等油田向天津供氣， 2021 年年供氣量近 6 億 m3， 2021年預計達 8 億 m3，管網(wǎng)長度 6894km，其中，高壓管線 591km，為 “十一五 ”期間天津市大力發(fā)展 CNG汽車大規(guī)模建設加氣站提供了保證。 三、 CNG 汽車的發(fā)展前景 CNG 汽車和加氣站具有廣闊的發(fā)展前景，主要表現(xiàn)在以下幾方面： l、汽車保有量的飛速增長、石油資源和環(huán)保的嚴峻形勢，決定了發(fā)展天然氣汽車成為解決能源問題和環(huán)境問題的重要途徑。天然氣容易擴散，以氣態(tài)進入發(fā)動機，在發(fā)動機中容易和空氣均勻混合，燃燒比較完全、干凈；可以提高熱循環(huán)效率，加快燃燒速度，充分利用燃燒熱能；同時CNG 辛烷值高，抗暴性能好，使用時不需要添加抗暴劑，不會稀釋潤滑油，因而使發(fā)動機氣缸內(nèi)的零件磨損大大減少，使發(fā)動機的壽命和潤滑油的使用期限大幅度增長。 有利于緩解能源緊張的供需矛盾。甲烷密度低，相對密度為 0． 55 左右，泄漏的氣體很快會在空氣中散發(fā)，在自然環(huán)境中難以形成遇火爆燃的條件，一旦壓縮天然氣從儲罐或管路中泄漏，泄漏點周 第 6 頁 圍會立即形成低溫區(qū)，使天然氣燃燒困難。據(jù)有關(guān)資料顯示，使用天然氣作為汽車燃料與汽油作燃料相比可以減少排放 90％ CO、 90％ S0 72％ HC、 39％ NOx、 24％ CO無粉塵排放，對改善城市環(huán)境有顯著作用。根據(jù)有關(guān)部門統(tǒng)計數(shù)字，截止到 2021 年我國一些地區(qū)共有天然氣汽車 20 多萬輛，加氣站 700 多座。有 40 多個州根據(jù)聯(lián)邦政 府的政策、法律，制定了本州有關(guān)強制和鼓勵使用 CNG等清潔燃料汽車的政策和措施，推動了 CNG 汽車發(fā)展和加氣站建設。壓縮天然氣汽車 (CNG)以其能耗低、污染物排放量小而受到各國的歡迎，是國際公認的最理想的車用替代能源。這只是時間性的問題這一天終究會來到的。燃料電池汽車 (FCEV)具有可與內(nèi)燃機汽車媲美的動力性能，在排放、燃油經(jīng)濟性方面明顯優(yōu)于內(nèi)燃機車輛。有效提高運輸過程中的安全，減少駕駛員的 第 4 頁 操縱疲勞度，提高乘客的舒適度。安全氣囊的出現(xiàn)在很大程序上保護了駕駛員和乘客的安全，大大降低汽車在碰撞時對駕駛員和乘客的緩沖，以過到保護生命安全的目的。可變力動力轉(zhuǎn)向系統(tǒng)因能顯著改變駕駛員的工作效率和狀態(tài)，所以在電動汽車上廣泛使用。當汽車行駛在不平坦的道路時汽車能能根據(jù)底盤和路面高度自動調(diào)整。而電動汽車給我們帶來無限樂趣外還能給我們勞累一天的身心得以放松。從發(fā)動機的燃油噴射點火裝置、進氣控制、廢氣排放控制、故障自診斷到車身輔助裝置都普遍采用了電子控制技術(shù)，可以說今后汽車發(fā)展主要以機電一體化。電動汽車將成為人們最為理想的交通工具。s safety, and greatly reduce automobile in collision of drivers and passengers in the buffer, to protect the safety of life. Intelligent electronic technology in the bus to promote safe driving and that the other functi