Abstract: Aiming at the current problems of coke oven flue gas application selective non-catalytic reduction(SNCR) or selective catalytic reduction(SCR) process denitration, a three-dimensional model of coupled SNCR+SCR in a new regenerator with ammonia injection space was established. Through the numerical simulation method, the heat storage index of different material physical parameters was optimized and evaluated, and the temperature and NO/NH₃ concentration distribution characteristics of SNCR and SCR reaction zone were analyzed. The results showed that the coupled process occurred sequentially from SNCR to SCR, and it had obvious temperature gradient variation and cascade utilization characteristics of waste heat. The residence time in the SNCR reaction zone was relatively large, ensuring the mixing degree of NH₃ and NO, and achieving a NO reduction efficiency of 63.8%. In addition, the SNCR process also had a competitive reaction of NO reduction and NH₃ oxidation, and the main reaction zone was located above the injection surface. Due to the low concentration and uneven distribution of NH₃, the SCR reaction zone had a low reduction efficiency, which was related to the structure of the regenerator and the catalyst coating area. However, the NO reduction efficiency of about 36% was obtained in a single SCR process. It indicated that the coupled process that NO reduction in the SNCR process and further reducing the NH₃ in the SCR process could achieve the outlet NO/NH₃ concentration to meet the emission standard, providing a theoretical basis for replacing the epitaxial SCR denitrification system.