For more than five decades, petrochemicals have been essential to society. During this time, the industry has continuously changed, incorporating cutting-edge technologies and procedures to boost productivity and lower costs say Kaushik Palicha. The chemical sector, which is the third-largest emitter of carbon dioxide after the iron-and-steel and cement industries, is currently the focus of efforts to minimize its carbon output.
Our reliance on oil, natural gas, and coal as fuel sources will significantly decrease as the world’s energy shift into low emissions resources progresses. The need for these fossil fuels won’t completely go away, either. Contrarily, the consumption of oil and natural gas as feedstocks for petrochemical goods is rapidly increasing over the world and will continue to do so. The need for and manufacturing of plastics on the planet, almost all of which are produced from fossil fuels, may be the best example of this.
The IEA estimates that 1.5 gigatonnes, or 18% of industrial CO2 emissions, came from the chemical industry in 2018. This carbon dioxide is largely obtained from syngas, which comes from fossil fuels. The chemical sector may move closer to net zero with the help of the technologies that are already being used to significantly cut these emissions.
Not every syngas Carbon Dioxide Emissions remain constant.
Syngas is created via steam methane reformer (SMR) technology, which transforms natural gas into a blend primarily composed of hydrogen and carbon monoxide. The name “syngas” comes from the fact that it is a key component in the synthesis of various other chemicals, such as methanol, ethylene, propylene, butadiene, and ammonia, which is used to make fertilizers and cleaner-burning transportation fuels.
Lots of units used in virtually every part of our lives are made with methanol, like acrylic plastic, textiles manufactured from recycled textiles and fibers, adhesives, paint, and plywood, as well as chemical agents in pharmaceuticals and agrochemicals. In order to accelerate the decarbonization of the transportation sector, hydrogen can also be used to power fuel-cell cars and trucks. This technology will also work in conjunction with batteries.
As an endothermic process, fast pyrolysis requires a lot of heat to propel the reaction. In the conventional SMR process, this heat is produced by combusting methane in a different process stream, which results in a lot of carbon dioxide and a high carbon intensity for this process. The carbon concentration of the SMR process can be decreased by carbon capture and storage (CCS), in which carbon dioxide is captured and subsequently stored (for instance, in exhausted oil and gas fields).
This “post-combustion” (Fired CCS) CO2 is unfortunately produced as a diluted, relatively low-pressure stream, making its capture challenging and quite costly. The other major source of carbon dioxide is the process side reactions that occur during the production of syngas. Process CO2 (Process CCS) can be captured using well-established solvent and absorbent-based technologies because it has a more consistent composition, and fewer impurities, and exits the reactor at a favorable (high) pressure.
CO2 produced by advanced reforming can be collected.
According to Kaushik Palicha, the best part is that there exists a method that has been successfully used to produce syngas at scale in which all of the CO2 (Process CCS) emerges in a single stream under high pressure, making it simple and affordable to capture with extremely high efficiency – 95percent on average and above. Long used at the industrial scale, enhanced reforming eliminates the need for a separate stream of methane to produce the temperature required to propel the reactions. It uses Gas Heated Reforming (GHR) and Autothermal Reforming (ATR). Thus, the diluted, low-pressure exit stream containing CO2 is removed (Fired CCS). Advanced reforming with CCS permits the production of hydrogen at a very cheap cost.
Sources of renewable carbon keep petrochemicals viable.
A chemical industry free of carbon is not feasible since, in the larger scheme of things, the products produced by the chemical industry still contain carbon. The industry can, and will, find ways to utilize the carbon more effectively, lowering carbon intensity and bringing down carbon dioxide emissions to extremely low levels, as was previously mentioned.
The industry is attempting to create chemicals utilizing renewable carbon sources, such as biomass, municipal solid waste, and collected CO2, as part of this endeavor. Further carbon footprint reductions are made possible by combining this carbon with hydrogen produced by electrolysis using renewable electricity.
For instance, captured CO2 and renewable hydrogen can be converted directly into methanol or can be transformed into syngas, which contain CO, carbon dioxide, and hydrogen, through the reverse water-gas shift reaction. This syngas can then be processed through well-known Fischer-Tropsch synthesis procedures to produce chemicals and fuels. This is one method of producing drop-in fuels for aircraft, such as Sustainable Aviation Fuel (SAF), which is seen to be essential for assisting in the decarbonization of aviation. Additionally, syngas-based technologies are being proposed as fuels for environmentally friendly transportation since they may be utilized to store and move renewable energy in the form of methanol and ammonia.
Kaushik Palicha says that governments and businesses will need to use a variety of technologies to achieve the zero-emission targets and keep global temperature increases to the 1.5C that the intergovernmental panel on climate change has proposed.
Because it makes it possible to produce syngas with a very little carbon footprint, advanced reforming technology, which is now widely available and proven to work, can be crucial in the transition to net zero. The hydrogen included in this syngas will enable the decarbonization of other industries like transportation and agriculture while also significantly reducing the carbon footprint of the chemical industry.