In the aluminum production industry, compressed air is essential for the pneumatic transport of raw aluminum powder. Yet oil contamination can cause quality defects and pipe clogging, as well as pose a fire hazard.
Established in 2005, Henan Wanji Aluminum Co., Ltd. (Wanji Aluminum) is one of the largest aluminum smelters in China. The facility has two electrolytic aluminum production lines with a total production capacity of 650,000 tons per year.
With such large production volumes, Wanji Aluminum needed not only high-quality, oil-free operation, but also the highest levels of efficiency, because energy accounts for one-third of aluminum production costs.
The company uses 10 Atlas Copco oil-free centrifugal compressors – five ZH 15000 and five ZH 10000 units – at its smelting plant. Designed for reliability and energy efficiency in the most demanding environments, ZH compressors are essential in conveying alumina to the silo and from the silo into the pot lines, carbon anode production, air instrumentation and pneumatic conveying of recycled particulate.“Atlas Copco’s ZH centrifugal compressors are equipped to guarantee quality and reliability for such customer processes that demand large volumes of air,” commented Mr. Sunghwan Kim, Product Manager of Atlas Copco Oil-Free Air division.
“Atlas Copco is a qualified supplier and its air compressor equipment has displayed excellent performance and super high stability since it was put into use, which is the key to our choice.”
ZH centrifugal compressors are designed to provide maximum uptime with minimum maintenance, whilst delivering energy savings. Milled impellers made from stainless steel 15-5 PH, spin tested at 115% of the nominal speed, ensure zero defects. Variable geometry flexible pad bearings, carbon ring air seals, labyrinth oil seal, AGMA Class A4 gears and stainless steel coolers contribute to trouble-free performance and long operating lives.
The horizontally split gearbox makes access for inspection and preventive maintenance easy and quick. The ZH compressor is specifically designed to optimize energy efficiency, and the entire unit is measured according to ASME PTC10. Oil-free turbo core unit provides the optimum combination of high flow with low energy consumption. Ample-sized cooling, low pressure drops and an efficient drive drain result in high compressor package efficiency, while the compressors also provide 100% pure, clean air that complies with ISO 8573-1 CLASS 0 (2010) certification.