Great interest is headed towards maximizing the use of natural gas for fueling vehicles around the world. This is due to its clean properties as well as its ability to limit harmful emissions. Compressed natural gas (CNG) is the fuel dedicated for natural gas vehicles (NGVs) that is widely used in the world. By the end of 2021, it is expected for NGVs to reach 30 million worldwide, according to NGV Global. For this reason, new technologies are emerging to help accelerate this transition efficiently. BioCNG technology is a simple, effective and innovative way that was developed to produce CNG vehicle fuels.
BIOCNG: An Alternative Fuel
BioCNG technology simply uses biogas in producing CNG. It’s more efficient than other options as it allows for the production of CNG at a lower cost. A research paper entitled “Bio-CNG: A Technology for Green House Gas Mitigation and Revenue Generation from Agro Waste” explained that BioCNG enables governments to efficiently manipulate solid wastes as well as tackling the problem of carbon emissions produced from burning agriculture wastes. This makes BioCNG a clean and low carbon technology. Additionally, the process of BioCNG produces enriched organic manure that can be used as fertilizer. The study stated, also, that BioCNG is similar to conventional natural gas in its composition and energy potential as it has a great potential to replace the CNG in the upcoming years.
According to the research paper, BioCNG is produced through four steps: The first step is the extraction in which biogas is produced naturally through a process called anaerobic digestion. An article published by Biogas and Biomethane website elaborated that this process is a biochemical conversion that occurs in biological substances such as agriculture residue, cattle dung, sugarcane press mud, municipal solid waste, sewage treatment plant waste; this process is carried out without the presence of oxygen at a certain temperature and with the continual mixing of the substances being used. The biogas usually consists of about 50-60% natural gas while the remaining part is composed of a combination of carbon dioxide and hydrogen sulfide.
The second step is the purification of biogas, generated from the anaerobic decomposition to get highly purified natural gas, which is environment friendly. This can be done by removing carbon dioxide and hydrogen sulfide. An article entitled “BioCNG Equipment and Technology- 4th in Series” stated that there are different purification technologies. The scrubbing method is cheaper than other technologies, but it requires constant freshwater supply so it has a high cost in the long term. The Molecular Sieve method is moderate in its cost and beneficial in the long term. Membrane Based-Catching Up technology is similar somehow to the Sieve. Another method is the Cryogenic-Based method in which methane is liquefied before other impurities so that biogas can be cooled to170 – 180 degrees Celsius to separate them.
The third step is pressurizing the produced biogas and filling the product in high-pressure cylinders. The last step is dispersion, where the BioCNG is ready to be distributed to be used in the vehicles.
According to the study, BioCNG production is cheaper than the production of the CNG and other fuels by 20-50%. In addition, a new system is developed by BioCNG LLC company related to this technology which is BioCNG™ units. These units are capable of lowering the expenses of cleaning the biogas and produce a low-cost renewable natural vehicle fuel. These units, also, have minimal maintenance issues. So, BioCNG represents an economic offer for fueling cars with natural gas.