Analysis and evaluation of the influence of heat storage material on coke oven flue gas exothermic process

Abstract

Sufficient heat storage and proper flue-gas outlet temperature were prerequisites for selective non-catalytic reduction (SNCR) denitrification in coke oven regenerators. This work performed an energy balance analysis on the established regenerator model to obtain a new thermal storage evaluation index-Total thermal storage temperature (TTST). Furthermore, ten cases of thermal storage parameters were set to analyze the effects of thermal effusivity and thermal diffusivity on heat storage and transfer. The transient simulation results shown that the channel shape of the lattice brick limited the uniformity of fluid-solid heat transfer and temperature distribution during the 30min commutation period, and the temperature window (1100~1300K) suitable for SNCR denitration slowly moved down. The increase of thermal effusivity led to the rise of heat storage and reduction of flue-gas outlet temperature. However, the transform in thermal diffusivity did not contribute substantially to the heat storage performance. Besides, the temperature-time-height equation obtained by fitting was used for predicting the suitable location of SNCR denitration temperature. The TTST was positively correlated with the flue-gas outlet temperature and negatively correlated with the heat storage capacity. The TTST evaluated the effects of material properties on heat storage and flue gas outlet temperature.

Coupling selective catalytic reduction process inside a coke oven regenerator: The influence of mixing parameters on NO reduction

“…We verified that thermal radiation had a minimal effect on the temperature distribution inside the regenerator [27]. On the other hand, the radiation effect produced by the injection stream was also weak [31].…”

“…Relevant data were collected at the operation site of the coke oven [27]. The volume fraction of the main components of the flue gas was measured before entering the chimney: CO 2 /0.206, O 2 /0.054, H 2 O/0.057, N 2 /0.685, and the NO x concentration was 400 mg/m 3 .…”

“…Currently, there are few reports on applying SCR to coke oven heating systems. To solve the problems mentioned previously in the NO x treatment of coking flue gas, this work combines the temperature distribution characteristics of the regenerator [27] and proposes a new-type regenerator synergistic SCR process. In this study, a suitable temperature window was selected as the coating area of the vanadium-based SCR catalyst.…”

Numerical simulation of NO emission reduction in coke oven regenerator with synergistic SNCR/SCR process

“…The On-site data collection was performed on the coke oven regenerator [8], and the relationship (6) of the inlet flue gas temperature at the top of the coke oven regenerator over time was obtained by fitting:…”

“…In order to solve the various problems faced by coking enterprises in the management of flue gas NOx emissions, this research applied SNCR/SCR technology to the coke oven regenerator to achieve NO reduction according to the unique heating system characteristics of the coke oven. Based on the research on the flow and heat transfer characteristics of the coke oven regenerator [8], this work had studied the influence of SNCR, SCR, and hybrid SNCR+SCR on NO emission reduction in the transformed regenerator. We can obtain the relevant parameters and theoretical support for the synergy of SNSR/SCR and coke oven regenerator for NO emission reduction through this research.…”