Software optimizes heat recovery
Heat recovery in ventilation systems can be a good way of improving energy efficiency on offshore installations. Coiltech, a producer of heat exchanger and ventilation systems, offers not only heat recovery systems, but also a dimensioning program for optimizing their operation.
On an offshore installation, effective heat recovery can generate savings in imported energy, such as diesel oil or electricity transmitted from shore. Where installations are powered by gas produced directly from the field, the owners can benefit by releasing this gas for sale or other uses.
On installations without heat recovery, warmed air from living and working spaces is normally vented to the atmosphere, while incoming air may have to be heated. But savings can be achieved by capturing the heat from the warmed air and using it to heat the inlet air. Coiltech has a heat recovery system for this purpose known as Ecoterm. It consists of a heat exchanger placed at the outlet of the ventilation system, which delivers recovered heat to another heat exchanger at the air inlet. Ecoterm can recover 50-75% of heat from the outgoing air, according to Ralf Sandman, Coiltech’s manager, marketing and sales, ventilation.
Where the user really stands to gain is through optimizing the efficiency of the system from a life-cycle perspective. Extremely high efficiency in heat recovery can be achieved, but typically also at an extremely high cost.
The current approach to optimizing such equipment consists of simple rule-of-thumb calculations, which cannot provide a reliable result. Instead Coiltech has developed a comprehensive optimization program - Ecoterm Optima - for dimensioning a heat reovery system to give the best bottom-line result over its lifetime.
The program requires some basic data, such as air flow, desired inlet temperature, geographical location, planned frequency of use, and so on. Financial data is also required, including the calculated rate of interest on the investment nd amortization period, the cost of hot water and electricity, and how these figures are likely to develop in the future.
Primed with all the relevant data, Ecoterm Optima will calculate the optimal efficiency for the heat recovery system, and also suggests the appropriate coils for attaining this level of efficiency. Over the lifetime of the system, the savings could be substantial.
For more information, contact Ralf Sandman, Coiltech. Tel +46 121 191 53, fax +46 121 146 43, [email protected], www.coiltech.com ([email protected] after mid-April).