The paper mills in China are using a new technology called Integrated Gasification Combined Cycle (IGCC) to make paper more efficiently. This technology helps to reduce energy consumption and greenhouse gas emissions. By combining IGCC with a cascade refrigeration process, waste heat from the papermaking process can be reused, making the whole process even more energy efficient. Compared to traditional cogeneration systems, paper mills using IGCC are more competitive in terms of energy efficiency and cost-effectiveness.