Qualification of waste heat recovery systems for CO2 capture in the cement industry
Norcem, Norsk Energi, Aker Solutions
In connection with full scale capture in Brevik, Norcem consider to use smoke tube boilers to recover heat from the cement process. Because this is unknown technology within the cement industry, this heat-exchangers needs to go through a technology qualification program.
In October 2016 Norcem together with Aker Solutions and Norsk Energi got support through the CLIMIT-program, to build a pilot to test smoke tube boiler under real conditions at the plant in Brevik. The pilot testing will form a basis for evaluate whether smoke tube boilers can be used for low pressure steam production.
The technology is known and used in the ferrosilicon processes, but in connection with cement processes is this considered as new technology.
The pilot was commissioned and ready for a start-up 1st of February, and tested 24/7 till 1st of Juli 2017. In the test period the smoke tube boiler was tested on flue gas with high and low dust content as well as high and low temperatures. The performance results shows good heat transfer coefficient and the boiler had a self-cleaning effect. It is still a residual risk connected to dust content and temperatures. Norcem together with Norsk Energi will therefore continue the project into a phase 2, to test the smoke tube boilers efficiency with higher temperatures and lower dust content. The goal is to reduce the risk to a level that is acceptable for HeidelbergCement, so this boiler can be used if full scale capture plant at Norcem.