Automobile "oil to gas" hot

On February 18, the Ministry of Transport issued the key points of energy-saving and emission-reduction work in the transportation industry, clearly pointing out the application of LNG (liquefied natural gas) and LPG (liquefied petroleum gas) vehicles in road transport, urban public transport and taxis.

The trend of “oil to gas” in automobiles is still to be strengthened. It is understood that natural gas vehicles can save about 30% of fuel consumption. Given the excellent performance of natural gas vehicles in saving energy, the “oil to gas” project currently on the market is extremely hot.

● How much is the concern? The “oil to gas” project is divided into two modes of CNG and LNG. CNG conversion is mainly targeted at light gasoline vehicles such as taxis and private cars, while LNG conversion is mainly targeted at medium and heavy diesel trucks.

There are two modes of LNG conversion scheme for heavy-duty trucks. The first mode is to convert the original fuel mode into a gas mode, that is, to convert the fuel engine into a gas engine and install the components of the natural gas fuel system - gas cylinders, pressure reducing valves, mixers, and electric ignition systems. The second mode is to convert the original fuel mode into dual modes of fuel and gas, that is, to convert the original fuel engine into a dual-purpose fuel and gas engine. The original fuel system of the diesel engine is unchanged, plus the same as above. In natural gas fuel systems, after the engine cylinders inhale the mixture of air and natural gas, a small amount of diesel fuel is injected from the original diesel injectors to ignite and ignite the combustible mixture of natural gas and air.

The second modification mode only needs to change the fuel line of the original diesel engine, add a gas line, and there is no need to replace the entire engine, so the cost is relatively low. Through the second model, the modified engine can burn diesel and LNG fuels, which is very convenient for heavy-duty trucks that carry long-distance transportation. At present, the second conversion model is more popular in the market.

A company employee who runs the “oil to gas” project in Henan told reporters that an important cost for LNG conversion is the cost of purchasing LNG cylinders. It is reported that LNG cylinders need to cool natural gas under natural gas conditions to liquid natural gas at -162 degrees Celsius and maintain its cooling state. The price of a single LNG cylinder is about 30,000 yuan, and the fuel carried by a single cylinder can be used by trucks for four or five hundred kilometers. If customers are engaged in long-distance transportation, they need to consider whether there is a refueling station during the LNG conversion; if the refueling stations in the middle of driving are far apart, it is necessary to consider the use of two LNG cylinders.

“If we assemble two LNG cylinders, plus the cost of working hours and some other accessories, the conversion cost of a heavy truck is usually over 70,000 yuan. More than 70,000 yuan is not a small figure for truck users. Previously, truck users would weigh the difference between the cost of retrofitting and the cost of fuel savings after conversion. For customers, the cost of LNG conversion is reflected in the cost of the balance." The above staff told reporters.

● Safety is to be discussed. The safety of the “oil to gas” project is considered by the above-mentioned staff. Compared with CNG retrofitting, the safety of LNG conversion is better.

CNG gas cylinders increase the gas storage capacity by compressing natural gas under high-density conditions. The internal pressure of gas cylinders is even higher. Usually, it can reach 20MP. Once it is used carelessly, CNG gas cylinders can easily become a “bomb”. . Although LNG cylinders have a low probability of “explosion” due to excessive pressure, LNG cylinders are prone to leakage if they are not tightly sealed, causing fire.

“Whether it is a CNG cylinder or a LNG cylinder, there are certain safety risks. If you want to minimize safety hazards, you must use a cylinder with safety qualification from a regular manufacturer, and you must carry out regular cylinder safety. Check.” The staff member concluded.

● Industry standards It is urgent for reporters to inquire about the official websites of the law enforcement agencies involved in the structural reform of the vehicles, such as the public security department and the Ministry of Transport, and have not found out whether the vehicles are allowed to change from oil to gas, and according to the National Road Traffic Safety The "law" stipulates that "any unit or individual may not change the structure and structure of a motor vehicle that has been registered". It is not in line with national laws to voluntarily carry out "oil to gas conversion" for vehicles. However, on the other hand, the “oil-to-gas” projects in various regions are extremely hot and the market seems to have defaulted on the legitimacy of “oil-to-gas” projects.

These two contradictory factors have caused the current law enforcement chaos for the "oil to gas" project. In April 2012, Shandong TV reported that Jinan’s private car “oil to gas” will be forced to dismantle gas cans; on June 16th, 2013, Voice of China “National News Network” reported that Suzhou had carried out “oil reform” without permission. "Gas" more than 1,000 driving school coaches can not carry out annual inspections. At the same time, however, the author also learned that Weihai, Chengdu, Chongqing, and other places have all made a green light on the “oil to gas” project and acknowledged the legitimacy of the “oil to gas” project.

Since the state has not introduced laws and regulations involving “oil to gas”, this has caused local law enforcement agencies to be at a loss, and some local law enforcement agencies simply over the air, and “red light” for all “oil to gas” projects, making “oil reform” Gas vehicles cannot be examined every year. In the “green lights” area, law enforcement agencies have hardly issued relevant regulations to ensure the safety of the “oil to gas” project. In the long run, it is easy to cause security risks.

Compared with gasoline and diesel, compressed natural gas and liquefied natural gas have significant economic and environmental benefits. The combustion emissions of natural gas are only water and carbon dioxide. Promoting compressed natural gas vehicles and liquefied natural gas vehicles is also a beneficial measure for improving air quality and preventing haze. The voluntary “oil-to-gas” behavior on the market coincides with the country’s intention to save energy and reduce emissions, improve air quality, and control haze. However, this spontaneous “oil-to-gas” behavior requires the country to introduce laws and regulations that respond to it, make it more standardized, and conduct regular safety inspections to eliminate potential safety hazards.