I decided to clean my office over the weekend, and came across the Power Magazine from June 2013. One of the feature articles is on the ARCTIC inlet conditioning system by Energy Concepts, Kiewit Power Engineers and Nooter/Erikson.
ARCTIC stands for Absorption Refrigeration Cycle Turbine Inlet Conditioning. And that’s precisely what it does.
Designed around the LM6000 (but also available for other engines), the ARCTIC uses heat from the gas turbine exhaust to power an absorption chiller which cools a heat transfer medium for use in the gas turbine inlet. The system can use existing inlet coils, and can also run in heating mode. This is of special interest to the aeroderivative engines, due to their multiple control limits, which cause them to have an optimum compressor inlet temperature (CIT) for best output performance.
The optimum CIT for the LM6000 is between 46F and 49F (and varies between individual units to a small extent). The ARCTIC system can be setup to control the CIT to that optimum temperature, no matter the outside ambients. According to the Power Magazine article, the system can also start and stop automatically with the gas turbine.
With a drop of only 120F in exhaust temperature (for the LM6000, this is from ~840F to ~720F), there is still energy available for other uses from the exhaust gases, including hot water exports or combined cycle operation (which is more likely on frame based units).
Overall, a very intriguing design concept, and if you’re in the market for a new or upgraded inlet chilling system for your gas turbine, definitely worth looking into.
To read more about ARCTIC, view the Power Mag article here: http://www.powermag.com/improving-warm-weather-performance-of-the-lm6000/