Study On The Mechanism Of Tamping Coke Quality And Its Carbonation Reaction

In recent years, tamping coking technology is developing rapidly with the shortage of coking coal resources. As the basic research laid behind the tamping coke production practices, especially in coke quality, that brought production and application issues. In this paper, Meishan Coke, Jining Coke, Jiahua Coke, Tianan Coke, Wuhai Coke and Tiexiong Coke were studied in order to get the characteristics of different carbon dissolved reactions which could provide a theoretical basis for tamping coke quality assessment.Different cokes have different characteristics in cold and hot property. In this paper,the M10 of the cokes we studied were about 4.0~7.2%, the CRI were about 24.2~33.6%and the CSR were about 51~65.5%. In all of the cokes we studied, the hot property of stamping coke was in the middle while the Ps, the M10 and the OTI was worse than top-loading coke which showed the differences of inner quality.For regardless of cokes, the Carbon dissolution reaction was mainly influenced by the temperature. Under isothermal conditions, with the increase of the reaction temperature, the reaction rate was accelerated significantly. Before 1100℃, the reaction rate of tamping coke and top-loading coke were small. When the temperature was over1100℃, the Carbon dissolution reaction rate of tamping coke was significantly higher.When the temperature was 1150℃ the reaction rate increased about 0.3 g.min-1than1100 ℃. While the Meishan coke increased 0.25 g.min-1. On the dynamics, the mechanism of carbon reaction dissolved fellow typical reaction model. In low temperature the Carbon dissolution reaction could be described as The homogeneous reaction. While in high temperature the reaction could be described as The unreacted core model. Between high and low temperature the reaction was controlled by chemical reaction and diffusion. We could use the Zero order reaction to describe the dynamics and the kinetic parameter related to Ps and inner quality and the Ea was about89~151.7KJ?mol-1. Non-isothermal reaction could be described as One order reaction.Carbon dissolution reaction could increase the coke porosity. For Meishan coke and Jining coke, the increase of porosity was mainly due to the Opening acts. While for the other stamping cokes the increase of porosity was mainly in the form of reaming. The pulverization rate reflects the structure quality of cokes which was influenced by temperature and conversion rate. Before 1100 ℃, the pulverization rate was about1~1.5%. When the temperature was over 1100 ℃, the pulverization rate is about2.7~3.7%. Besides at 1100℃, with the improvement of conversion rate, the pulverization rate of tamping coke was more serious than the top-loading coke.The reaction rate directly affected the CSR. At 1000 ℃,the carbon dissolution reaction rate was small and the CSR30 of these stamping cokes were about 59~63%.When the temperature was over 1150 ℃, the reaction rate increased rapidly and the CSR30 of these stamping cokes were about 58~61%. When the temperature was between1050~1100℃, the CSR30 of cokes were damaged serious. When the reaction time was 2hours, compared with non-isothermal and 1100 ℃ conditions, the CRI was about0.5~2.5% lower while the CSR was about 0.3~1.5% lower.