Combustion Processes: Process Heating and the Energy-Carbon Connection
More organizations are working to reduce their carbon footprint, whether it’s to meet corporate sustainability goals, follow local regulations or promote social responsibility. Those involved in industrial process heating — which typically includes the melting, curing, forming or heat treating of metal — are no exception. Over the past several years, manufacturers and users of process heating equipment have become increasingly interested in its role in carbon emissions. An essential step in this decarbonization journey is understanding and managing energy consumption.
Process heating requires energy input. The energy sources for process heating most frequently include the combustion of carbon-based fossil fuels, such as natural gas, propane, fuel oil, diesel or coal. Figure 1 shows the chemical process for methane combustion (i.e., natural gas). During combustion, methane (CH4) combines with oxygen (O2) to form carbon dioxide (CO2) and water (H2O). The situation is the same for any carbon-based fuel.
In basic terms, if you have a combustion process on your site, you are emitting CO2. Now consider all the combustion occurring across the globe at any given time and all the CO2 being released.
In addition to the combustion process itself, the electricity consumed to support this process has a carbon component. For example, most combustion processes use electricity to operate combustion air supply blowers, exhaust blowers, circulation fans, conveyors and other items.
So, combustion and electricity consumption both contribute to your site’s carbon footprint. Fortunately, government and corporate actions are creating new opportunities for more-sustainable and lower-carbon process heating methods, and incorporating best practices can improve existing processes — optimization and proper maintenance are key to reducing combustion-related carbon emissions. The U.S. Department of Energy has valuable resources on a variety of process heating topics, and for additional information, check out these initiatives from the Industrial Heating Equipment Association.