For decades the personnel at Helical Energy have been innovating the heat recovery sector and will continue to do so, having invented circular gas turbine heat recovery units (CWHRU) and developed the concept with several derivatives.

 

It is no surprise therefore that the HELICAL personnel would continue development of the circular concept and has now invented a patent pending third design that far surpasses the benefits of the earlier sleeve damper and flat louvre damper. The DIAMOND® exhaust damper differs from the other two designs by not having a central core. Instead the conical diamond shaped damper is intrinsically strong and can withstand enormous weights even at extremely high temperatures. This design is a step change for the industry, delivering better performance with reduced weight, space and overall cost. However, on top of this there is a fundamental process benefit - it delivers close to linear exhaust gas flow to the coils with extremely low damper pressure drop – circa 1.2mb, which cannot happen with the earlier designs. This additional advantage stems from the fact that the diamond shape has 50% more surface area than the flat design, allowing the blades to be larger and diamond shaped (one of the key aspect of the invention), where the narrow blade tips, as they start to open and close, allows only a small amount of exhaust gas to pass, which increases proportionally, to the damper opening position. The inherent profile of the DIAMOND® exhaust damper allows for a uniform flow distribution into the coils, whilst providing a low pressure drop with a centralised inlet.

 

A testament to our customers’ confidence with the strength and simplicity of this new design are the orders they have already placed. These horizontal inlet COTSG units are being fired to 900C and delivered in the second quarter of this year.

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