How Does a Cannon Boiler Work?

Boiler Types

• Boilers fall broadly into two types: firetube and watertube. Firetube boilers have water tanks in which tubes are immersed. After burners heat air that is passed through the tubes, the tubes heat the water and form steam. Watertube boilers have water-filled tubes that are heated by air-filled furnaces. According to the Food and Agriculture Organization of the United Nations, firetube boilers are used most commonly in small- to mid-sized applications, such as wood industries. Watertube boilers are used in larger applications, such as powering turbine generators.

Heat Recovery

• Heat recovery steam generators (HRSGs) capture waste heat from one application and convert it into additional useful purposes in another application. Using this technology, boiler heat that would normally be expelled into the atmosphere is recycled to power turbo-electric generators, for example. Cannon Boiler Works holds a license to use the Gas Technology Institute’s patented TMC (transport membrane condenser) system in its Ultramizer system. According to Cannon, this gives its boilers up to 95 percent more efficiency over non-HRSGs. A primary component of the Ultramizer is its condensing economizer.

Economizers

• According to the U.S. Department of Energy, the solution to recovering waste heat most efficiently for repurposing is by using a condensing economizer. Cannon explains the importance of temperature in economizer operation, with traditional economizers functioning in hotter environments than condensing economizers. Energy savings increase at lower operating temperatures, because condensation is unable to form and does not have to be removed in addition to hot gases. To facilitate this step, condensing economizers are located downstream of the boiler evaporator, where gases are naturally cooler, according to PG Thermal.

Considerations

• Older Cannon boilers can be retrofitted with condensing economizer technology. Retrofit upgrades eliminate the need for replacement cost of a new boiler, while they increase average existing boiler efficiencies of 60 to 70 percent up to 90 percent. Newer condensing economizers sustain less damage from corrosion than in older boiler installations. They are made of stainless-steel construction, compared to older carbon-steel models. For heavier duty applications that produce more highly corrosive gases, Cannon makes custom-designed economizers.