PM emissions from current vehicles in Beijing could be reduced by approximately 19% by simply blending 20% synthetic diesel with currently available diesel, according to a new study by Tsinghua University, the Desert Research Institute in Nevada and Greyrock Energy, a developer of gas-to-liquids technology. This improvement can be accomplished with no changes to the current vehicle fleet, no material changes to infrastructure and no involvement by the consumer.
Other benefits from a 20% fuel blend include reductions in carbon monoxide (CO), nitrogen oxides (NOx), and methane (CH4) emissions by a projected 24%, 5.5%, and 11%, respectively. The control of CH4 emissions is important since it is approximately 84 times more potent as a greenhouse gas than CO2, measured over a 20-year period. Additional advantages of synthetic fuel use include improved fuel economy, enhanced vehicle performance and increased engine life.
Beijing’s poor air quality is the result of emissions from vehicles, manufacturing plants, the use of coal for cooking, and other sources. Diesel vehicles were chosen for this study since they contribute about 74% of the particulate matter/soot (PM) from vehicle emissions, one of the major sources of smog and poor air quality in Beijing.
Synthetic liquid fuels have been produced from resources such as natural gas for many decades. However, due to high production costs, they remain an insignificant portion of the market, at less than 0.25% of the total global volume of oil products. Greyrock, a company headquartered in Sacramento, California, provides systems that produce premium synthetic diesel fuel and gasoline blends from various sources such as flare gas, natural gas, industrial waste gas, CO2, and biomass. Greyrock’s premium synthetic diesel fuel contains no sulfur and features premium properties such as high cetane. When used in diesel fuel engines, synthetic fuels result in lower emissions as compared to engines that consume traditional petroleum based fuels.
The World Bank reported that in 2015 that China produced approximately 2.08 billion m3/year of natural gas associated with the production of oil, which was flared primarily due to lack of infrastructure and available markets. This volume of gas would be sufficient to produce up to 432 million gallons per year of synthetic diesel, kerosene, and gasoline fuels, and if blended at 20 volume% with petroleum based diesel, it would provide about 2.16 billion gallons/year for China’s diesel vehicle fleet. In addition to the production of synthetic fuel from gas that would otherwise be flared, Greyrock technology may be used to produce synthetic fuel from China’s abundant agriculture and forest biomass residues.
The study also concluded that if this synthetic fuel was produced from the 2.08 billion m3/year of associated natural gas in China as an alternative to flaring, then NOx, CO and PM emissions could be reduced by a projected 109, 590, and 9.8 thousand tons/year in China, respectively. In addition, the greenhouse gases CH4 and CO2 would be reduced by up to 154 and 5,270 thousand tons per year, respectively.