At Tronox’s Namakwa Sands ferro-alloy smelter near Saldanah Bay in South Africa, eight of GE’s Jenbacher J620 gas engines are generating power from off gas from the furnace.
The engines were to operate at a maximum load of 1700kWe. During the first years of operation the gas composition has been shown to be stable and the engines have been performing well. Gas stability is often a challenge for special gas applications and this is a positive development. Standard mineral based oils have sub-optimal performance for engines operating on this fuel. Following commissioning GE recently completed an oil approval test with high quality synthetic engine oil on one of the engines. Based on the positive results from the engine oil approval test, Clarke Energy and GE started an additional test at this specific engine by increasing the power output last September.
The team including Erwin Amplatz and Michiel Thomas from Clarke Energy and Alexander Zuschnig from GE were able to increase the electrical output of the engine to almost 2MW. The specific electrical output was increased to 1,970kWe (at 13bar BMEP).
Following the successful results over a 3,000 hour testing phase this gives the potential to upgrade the remaining engines, and also improve future performance of engines operating in the challenging furnace gas market in South Africa and globally.