Reduced noise emissions at three times longer service life
Extracting limestone and processing quicklime products for various sectors of industry form the portfolio of the Wuppertal-based company Oetelshofen Kalk. 75% of its products are supplied by road or rail to local industry in a radius of 80 km. Around 100000 tpa limestone flour is supplied, for example, to the flue gas desulphurization plants of the power stations along the River Rhine. Annual production currently totals 2 million t. To maintain this output rate and ensure environmentally compatible production in the future too, Oetelshofen has made some investments – in new firing technology from QualiCal as well as wear protection and noise control systems from Sandvik.
“In a pilot project, we have installed new firing technology at our facility. With an efficiency rate of 90%, the PFR kiln (Parallel Flow Regenerative principle) has attracted worldwide attention,” reports Moritz Iseke, Managing Director and great-grandson of the company founder. In addition, great importance has been attached to reducing noise emissions. And for that reason, the company contacted Sandvik. The company could draw on first, positive experience with Sandvik WT7000 rubber wear plates (Fig. 1) installed six months previously as part of the lining of an around 6 m2 large hopper for the kiln feed. Key features of the modular system are easy fitting of the plates and the reduction of the noise level by around 20 dB. The human ear perceives this as a 50-% reduction in noise emissions. Convinced by this, the company management opted to fit the new 120 m2 tipping hopper with WT7000 rubber plates (Fig. 2).
It was essential to choose the right material to meet the demands and requirements of the hopper, which is designed to handle around 500000 t rock per year. After a planning and consultation phase, the company decided to buy
1500 pieces of 50 mm thick rubber liners mounted with welded studs, to meet the requirements for up to 60 t rock per trough, with a product size of up to 140 mm. If the sharp-edged has worn out the plates can be replaced quickly and safely, at low cost, by exchanging individual plates which are quite handy with each plate weighing 5 kg and measuring 300 x 300 mm in size.
through recyclable material
“The base element of the hopper is protected against cracks and deformation by the patented modular plate system, it remains in its original shape, the special liner lip protects against fines infiltration between the gaps, and an at least three times longer service life is another plus. None of these features are achievable with conventional steel lining” explains Selim Sahin from Sandvik. The 100-% rubber plates boast other advantages, like, for example, simple cutting and high environmental compatibility thanks to the fact that they are made from recyclable material. In addition, the quarry hosts the largest eagle owl population in Europe. With double-shift operation in the quarry, the nocturnal hunters are also grateful to Sandvik for their peaceful rest during the day.
Sandvik Mining and Construction Central Europe GmbH, Essen (D), Selim Sahin, Sales Manager Wear Protection/Screening Media, Tel. +49 201 1785-361,
E-Mail: selim.sahin@sandvik.com, www.sandvik.com
