Believed to be the only company offering this technology globally, this innovative design requires no moving parts, has no parasitic loss resulting from additional fans or controls, and a rugged yet lightweight casing that minimizes the structural support and installation cost. The entire unit is manufactured from corrosion-resistant materials providing a long service life.
The design has been installed in a food processing plant in Missouri, USA. In total, five BEI economizers were installed at the plant; two were conventional boiler feedwater models, however for the other three, the client’s significant cold water heat sink provided an ideal opportunity for full condensing heat recovery in a conventional economizer installation above the boiler - utilizing BEI’s trailblazing Type III configuration.
HeatSponge Type III Configuration
Around 10% of the energy inputted to a boiler is lost through latent energy losses. Water formed in the combustion process is turned into vapour which cannot be recovered inside a steam boiler passing into the atmosphere. Economizers that utilize cold-water heat sinks enable recovery of this latent energy available in condensing, unavailable when in typical hotter boiler feedwater sinks. Condensing economizers can result in up to four times the higher rates of heat recovery than non-condensing designs.
Most indirect contact economizers on packaged boilers are located above the boiler with the exhaust gases entering the bottom and travelling vertically upwards. This orientation poses significant problems on heavy condensing installations for two key reasons:
- Optimum condensing requires the gas flow to be vertical down
- High levels of condensing risks water falling back into the boiler exhaust resulting in significant boiler damage
BEI’s type III configuration incorporates an internal three-pass exhaust gas path that allows the gas to enter vertically up from the bottom, yet transition to gas flow down over the heat exchanger and exit from the top in a conventional orientation.
An isolated sump ensures no condensate can ever enter the boiler and using the draft available in the combustion air fan, we do not need an external fan to overcome the draft loss across the economizer.
“At a time of escalating energy prices, this technology stands to reshape the global approach to heat recovery,” said BEI president Vince Sands.