The Huoerxinhe coal mine wanted to increase its production, so they redesigned their coal separation process. By analyzing the raw coal, they found ways to improve the separation efficiency. They increased the size of the coal particles, added new separation systems, and upgraded their equipment. As a result, they were able to increase the plant's capacity from 3.0 million tons per year to 5.0 million tons per year. This means they can now produce more clean coal with lower ash content, making their operation more efficient and profitable.