Corus out of the traps at Welsh plant
Llanelli, UK – Corus has installed steam traps at its Trostre Steel Works, in Llanelli, South Wales, which produces over 400ktpa of packaging steels for the UK market. The units were added onto a continuous annealing (CAPL) process line to give the steel its required hardness.
The CAPL process line uses around 600 tonnes a week of saturated steam supplied at 8 BarG. The operation involves the use of two entry and exit reels. At any one time there will be over 1,000 metres of strip running through the line.
The furnace section of the line heats the strip to a selected temperature within a 650°C to 690°C range. This temperature is maintained through the mid section and the strip is gradually cooled in the final furnace.
By passing the strip through cooling chambers and a quench tank further cooling is achieved. Finally the strip is recoiled for further downstream processing.
The site had previously installed a GEM Venturi steam trap following a bucket test on a line drainage trap, which had provided 60% savings.
Following the appointment of Dr Darryl Lewis as energy operations manager at Corus, GEM parent company Thermal Energy International (TEI) was asked to survey the CAPL process line and V Stand Mill.
The study found that of the 12 steam traps surveyed 25% had failed closed and 17% had failed open. Following these findings, Corus invested in 18 GEM Venturi orifice steam traps to replace the existing mechanical steam traps on the CAPL process line.
Based on nominal consumption rates of 600 tonnes of steam a week, TEI reckons that the GEM traps are providing around 5% energy savings which equates to £0.5K a week based on a gas tariff of £4.4/GJ and condensate waste treatment costs. These savings, it said, will provide a payback on the GEM steam traps in around 30 weeks.