Climate change, the diminishing availability and subsequent cost of fossil fuels, and greenhouse gas generation concerns have had a tremendous effect on manufacturers and operators in the boiler industry. Older, poorly maintained units at commercial facilities, institutions, and industrial complexes cost their owners too much money to continue operating in their current conditions, particularly in light of recent federal regulations and global treaties. As a result, many owners are considering redesigning and rebuilding their boilers to make them more efficient and capable of burning alternate fuels. New start-up units might be a better alternative, as they are designed with efficiencies and flexibility in mind. The boiler industry is taking advantage of green energy practices and fuels to reduce costs and convert more heat input into usable energy output.
“Green energy” is a term with a far-reaching definition. In its broadest sense, green energy is the efficient manufacture and use of power without adversely impacting the global ecosystem. Many critics want to limit the discussion to the use of renewable energy sources like solar, wind, animal waste, and hydrodynamic power, but the issue encompasses much more. The reality is that, while conversion to completely renewable energy is a grand goal, the existing infrastructure will not stop demanding electricity in the meantime. The boiler industry must find a way to meet the demands of power producers and users while reducing the overall impact on the environment. That’s what the boiler industry is doing.
Boiler manufacturers are approaching the need for green energy on three fronts: efficiency improvements, alternative fuel usage, and post-combustion controls. Owners of the equipment in the boiler industry are in full support of these methodologies, and are responsible for providing the funding and driving the changes. All three of these areas are being addressed simultaneously, and the results to date show a marked improvement in the amount of greenhouse gasses generated, a reduction in fossil fuel usage, and more steam and energy being generated per pound of fuel used.
Efficiency improvements in the boiler industry are helping units generate even more electricity without increasing the amount of fuel used in the process. Such steps include the use of redesigned burner fronts; the installation of economizers, preheaters and air heaters; air and fuel-flow tuning; upgrading or replacing instrumentation and controls; and the installation of gas-fired turbines with Heat Recovery Steam Generators (HRSGs).
Eliminating sources of heat loss is also accomplished through installing insulation, reducing air leakage, and capturing condensate and heat from boiler blowdown streams.
Alternative fuel usage includes firing biomass, tire-derived fuels (from used tires), old railroad ties, post-consumer waste, co-fired fuels, replacing oil and coal with cleaner burning natural gas, firing methanol and methane gas. Post-combustion controls include the installation of treatment systems for NOx, SOx, and HCl, improved particulate collection systems, stack-mounted continuous emissions monitors (CEMs), and the installation of utility power HRSGs with auxiliary burners to destroy emissions and convert any unburned fuel into energy before it is exhausted.
The boiler industry is making changes and upgrading its equipment, processes, and practices to take advantage of green energy technology, save money, and have a positive impact on emissions and the planet’s ecology. By using energy more efficiently, using renewable fuels, and reducing greenhouse gasses, the industry is making a real contribution to conserving available resources while still meeting the needs of existing and emerging economies.