Most frequently used diesel fuel production process includes several steps: treatment in distillation columns, cracking and compounding process.
Processing in distillation columns is the first step which is necessary for diesel fuel production. Oil is heated at constant pressure up to the temperature of 180-360ºC. This makes it possible to divide “black gold” into separate fractions. The finished fuel outlet after processing in distillation columns is relatively small (about 20-25%). The process features little expenditure in terms of time and money.
The process of cracking is required for long molecules breakdown. It helps to obtain components that can be burned in diesel engines in large amounts. There are several approaches to the process of cracking. In thermal cracking oil is heated, while various catalysts are not used. In hydrocracking oil reacts with hydrogen. Catalytic cracking cannot be performed without metals, which act as catalysts. Nickel, iron and platinum sponge are most frequently used.
After the second-stage, the output of diesel fuel can reach 70-80%. But it is still not in a marketable condition, due to the presence of sulfur and other contaminants.
At the stage of compounding the products of cracking and direct distillation processes are mixed in the proportions specified with the process. Additives are also added at this stage. If the sulfur content does not exceed the permissible limits, diesel fuel can be shipped to the end user right after blending. GlobeCore USB plants are used to mix all the individual components. Through the use of hydrodynamic shock and injection method, this equipment allows to obtain high-quality diesel fuel, which does not break down for at least 180 days.
Today, three types of diesel fuel are available in the market: winter, summer, and Arctic. The main difference between, let’s say, winter and summer diesel fuel lies in their crystallization temperature and the temperature of complete solidification. It depends on a method used for fuel production.
Today winter diesel fuel can be produced by using two methods. The first one is nearly the same as for summer fuel, but with lowering of carbonic fractions final boiling point to 20°C. Also, winter diesel fuel can be obtained directly from summer fuel by adding special depressants that are able to lower its pour point. At that, limiting filterability temperature remains unchanged.
Winter diesel fuel can also be obtained by adding kerosene to summer diesel fuel. The lower the ambient temperature, the more kerosene is needed. We should note that this method is not economical and the use of real winter diesel fuel in most cases is cheaper.