Improving the Coke Property through Adding HPC Extracted from the Mixture of Low-Rank Coal and Biomass

To effectively utilize low-rank coal and biomass in the coking process, through the dissolution method, hypercoal (HPC) was produced, and its performance as an additional component in the coking process was also investigated. The cold strength of coke was tested using an I-type tumble tester and a universal testing machine; the carbon structure of the HPCs was examined via thermogravimetry (TG), X-ray diffraction (XRD), and Fourier transform infrared spectrometry (FT-IR) analyses. The results revealed that the thermoplastic properties of HPCs and the coke cold strength increased compared to raw coal. There is a positive linear relationship between the cold strength of coke and the order degree of the HPCs. As the biomass amount increased, the order degree of the HPCs greatly decreased, resulting in a decrease in the coke cold strength. When the amount of biomass was 20%, the caking index (G), drum strength, and compressive strength achieved maximum values of 95.21%, 83%, and 7.13 MPa, respectively. In addition, a caking mechanism of the HPCs is proposed.