Metal & Mining
| Mon 08 Dec 2025
Beijing, Dec. 8 -- Huaneng Coal Tech Research Co Ltd, Walnut Coal Mine Huaneng Qingyang Coal and Electricity and Huaneng Coal Ind Co Ltd have sought patent for Variable Coal Pillar Type Mining Method. This invention was developed by Ma Xingen, Pan Bo, Yang Guang, Wu Yue, Zou Qinghai, Yang Xiaoquan, Xu Sen, Xu Xiaoping, Jiao Jian..