The Combustion System PACS

At the core of the Top Cycle gas turbine, and therefore at the very core of the BTC plant is the combustion system, converting chemical energy to thermal energy for the turbine. The combustion in the PACS -Phoenix Advanced Combustion System, is done at ultra-wet conditions. The challenge is to achieve combustion under these conditions, especially with Syngas which has a relatively low energy value.

The combustion system is a combination of our patented burner technology in combination with the combustion chamber design and how it integrates with the surrounding gas turbine. The objective of the PACS is to handle the vast amounts of steam being fed into the combustion chamber, so that the excess air can be reduced to a minimum and also to be able to recycle the heat from the HFB gasification system when running on biomass syngas in the BTC plant.

Hydrogen is expected to be an important energy carrier in the future energy system and vital to the energy transition towards a sustainable energy system. Converting Hydrogen to electricity can be made through fuel cells or through combustion. For large scale, stationary applications, gas turbines are superior in terms of investment and efficiency. In order to utilize Hydrogen as fuel, it’s important to be able to reduce NOx emissions that is normally formed when burning Hydrogen. NOx is formed when flame temperatures are very high. Through our patented burner design, we are able to achieve stable combustion with a very even heat distribution during combustion, resulting in stable flue gases for the gas turbine and ultra-low NOx emissions.

The PACS is superior for fuel flexibility. In our tests at TU Berlin and at our own test rig Scarlett in Stockholm, we have been able to switch from 100% fossil gas to 100% hydrogen and from 100% LPG to 100% syngas, with stable and maintained flame through the transition and switch. Very few systems have this capability. This results in a combustion system and gas turbine with superior fuel flexibility.