NOTE: The sponsor of this content may contact you with more information on this topic. Click here to opt-out from sharing your email address with this sponsor. (This link will not unsubscribe you from any other BIC email list).
It’s estimated that 20%-50% of energy is lost as waste heat in manufacturing processes where heat is used to make products. Waste heat is energy generated that goes unused and is lost to the environment. Waste heat can come from process systems, flue gasses, generators, turbines, cooling water, equipment surfaces, etc. But waste heat doesn’t have to go completely to waste. With that much loss, there are opportunities and technologies called waste heat recovery units (WHRU) that allow manufacturers to put it to practical use.
Heatec oxidizer with a WHRU.
The reason for heat recovery is twofold. The first is environmental responsibility. Many of us separate glass bottles, aluminum cans, and cardboard boxes from the regular trash so that they can be recycled. Most who do this will do it out of a sense of obligation to reduce their carbon footprint. You could look at heat recovery as another form of recycling. By reusing the heat that would otherwise be lost, you help reduce the amount of emissions released into the atmosphere and reduce your consumption of limited resources. Climate change will continue to be a hot topic of debate around the world. Manufacturers and industries have and will continue to play a major role in reducing waste and consumption.
Reducing your environmental impact also helps save you money, which is the second reason for recovering heat. It’s true that capital costs will be more for the additional equipment but those costs will be recouped in as little as two years in many cases. For the same reasons heat recovery is good for the environment are the reasons that heat recovery is good for the bottom line: less waste and less consumption equal increased efficiency. Investing in a recovery system is one of the most practical and logical investments a company could make.
There are a number of different methods and equipment for heat recovery. Which method to use depends on the quality and temperature of waste heat. Waste heat is classified as high temperature (above 752˚F, 400˚C), Medium temperature (between 212-752˚F, 100-400˚C), and low temperature (below 212˚F, 100˚C). Waste heat at medium and high temperatures is the easiest to recover but it is possible to recover waste heat with lower temperatures as well. Medium and high-temperature waste heat typically comes from direct combustion processes and from the exhaust of combustion equipment. Low-temperature waste heat usually comes from parts, products, and radiation from equipment.
Heatec WHRUs on an offshore platform recover waste heat from gas-powered turbines.
Knowing the temperature, quality, quantity and use of the waste heat will determine the type of recovery system you want to use. Types of heat recovery systems consists of economizers, recuperators (usually heat exchangers), regenerators, heat pumps, heat recovery steam generators, thermal oxidizers and more. You can have multiple systems running together.
The industries that consume the most energy in the United States are bulk chemical, refineries, mining, iron and steel, food processing, pulp and paper, agriculture, and construction. But, almost any industrial process that has waste heat can use a heat recovery system. For example, you could use a WHRU for air preheating. Preheating air will help a gas fired burner burn more efficiently and use less fuel gas. Or, an economizer captures exhaust heat to heat the liquid or gas process medium before it circulates through the main heating unit which again, helps reduce energy consumption. Recovered heat can also be used to generate power, for comfort air heating, put back into the process, and more.
If you decide to add a WHRU to your system for environmental concerns, to save money or both, Heatec can help you evaluate your process and decide which type of system is best. Give Heatec a call at 423-821-5200 or visit www.heatec.com.
