Waste not want not – Heat recovery for construction materials company

Waste not want not – a gem of a hidden heat source for the customer and the environment

Maziak’s customer is a construction materials company with a production process that uses 315kW of energy—a lot!  Water needs to be pre-heated and remain at a constant 28oC.  Using gas burners to heat the tank, the process uses up to 240ltrs of water per minute.  About 80% of the power used to generate the required compressed air is wasted as heat from the top of the compressors (252kW of energy).

heat recoveryMaziak proposed reusing the wasted heat to pre-heat the hot water tank and reduce the amount of natural gas used. This also removed the heat from the compressor during hot periods that can cause tripping issues.  Heat exchangers were fitted to the compressors and via a newly installed closed-loop water system, this heat warms the water, thus reducing the need to run the gas boiler.

The cost of the project was recouped within a year and the customer is now saving a considerable annual sum on its energy bills.  The customer is also capturing more heat than it can use and is looking into utilising this heat to run underfloor heating in a new building.  A huge benefit to the customer. but also a positive impact on the environment.