Biomass can play a key role in economic development and emerge as a significant alternative to fossil fuels. In this article, we will discuss why fossil fuels are preferred over biomass fuel by the industrial sector.
Pyrolysis and the Promise of Biochar
The end application of biomass mostly depends on the feedstock type and the char conversion process. When processed under controlled conditions, biomass converts to char (or biochar). With the presence of high carbon content in biochar, they are highly dependent on the processing conditions of biomass (or fuel), e.g. wood char produced from pyrolysis at low or no air flow can expect to have high carbon and hydrogen with minimal minerals/inorganic presence.
Gas produced under same condition will have a high presence of heavy aromatic carbon and nitrogen gas. However, under the same conditions, if physical structure of biomass varies, the output results can fluctuate to a significant level.
The temperature, pressure, elemental composition, particle size, physical structure (e.g. density, moisture presence, molecular structure, pore size), heating rate, the maximum temperature of process, retention time during the conversion process can change the composition of biochar produced.
Biomass when converted to char has multiple applications with minimal effect on the environment. It has applications in toxic metal remediation and can remove harmful contaminants from soil which can damage plant growth and soil nutrients.
Char has potential to stabilise cadmium, lead, chromium, zinc, but they are found to be most effective in stabilisation of lead and copper. Researchers have found the potential application of biochar in a range of applications, viz. carbon sequestration, solid waste management, green electricity production, wastewater treatment, iron making process and building construction.
Why Fossil Fuel is Preferred Over Biomass Fuel?
Despite the significant contrast of applications and proven to have minimal effect on the environment, why is biomass not preferred or unsuccessful to attract the commercial sector? The answer relies on biomass processing technologies that still need to develop economically feasible. Besides fuel cost, the initial setup of biomass-based technologies need high capital cost, operation and maintenance cost, which eventually lead to a significantly higher cost of end application when compared with fossil fuels.
In most FMCG, sugarcane and fruit-based industries, biomass is produced as their waste, and legal compliances expect them to dispose of their waste sustainably. Industries spend substantial money to dispose of their waste in agreement with legal and environmental regulations. Researchers termed it a negative cost, which means that industries intend to pay to take this biomass off from their facility.
This could bring a possible opportunity to biomass processing plants to get paid or acquire fuel at no or negative cost. But most processing facilities are far from fuel (or biomass waste) sources, and cost of transportation are significant enough to compare the economics of fuel acquirement with fossil fuel costs. Moreover, processing technologies need cleaning and maintenance which further add up to the cost.
The overall economics of biomass-based electricity and any other end-use process cost higher than fossil fuels, making it very difficult to attract industries to invest in biomass over fossil fuels. Research suggests that biomass processing facilities that are available within the periphery of 200km from the fuel source will cost biomass (or fuel) at zero to negative value, improving the overall economics to a significantly comparable level to fossil fuels.
The Way Forward
To address this issue, small-scale plants must be installed in nearby areas and critical focus is vital on economically small scale biomass processing plants. Considerable research work is going on with small scale gasification plants capable of producing electricity at a small scale, but that is still under pilot project and no large-scale implementation has been found so far. Pyrolysis plants are also under the research zone, producing biochar, but this method is still under research development.
To reach targets of global temperature and carbon emissions into the atmosphere set by the UN at Climate Summit 2015, this area of research is a potentially critical area that can play a significant role in overtaking biomass over fossil fuels.