Author: Zhang Xinggang Source: China Chemical News Date: 2012-3-14
This reporter (Reporter Zhang Xinggang) has learned from Qingdao Lianxin Chemical Co., Ltd. that the layered control reactor developed by the company for deep sulfur-resistant conversion of high-concentration carbon monoxide (CO) and high water-gas ratio raw gas has been successfully applied in the synthetic ammonia units of many chemical companies. The operation results show that the use of this technology can still control the hot spot temperature of the bed below 450℃ under the harsh conditions of conversion load as low as 25%~30%, successfully solving the problem of overheating of the conversion reactor that is prone to occur when high-concentration CO and high water-gas ratio raw gas are started at low load.
It is understood that the patented technology of the reactor and the series of products QDB catalysts have been successfully applied in Henan Zhongxin Chemical Co., Ltd. When the conversion load is 25%~30%, the conversion section can still operate stably. After Anhui Jinmei Zhongneng Chemical Co., Ltd. adopted this process and reactor, the catalyst of a converter reactor was loaded in two layers, and QDB-03 catalyst was selected. When the conversion section was gas-guided, the conversion load was only about 30%. In order to avoid overheating of the converter caused by low-load start-up, they adopted a special gas-guiding method to steadily control the bed temperature, and the hot spot temperature of the converter was controlled below 450°C.
According to reports, the CO concentration in the raw gas produced by the pulverized coal gasification process is as high as 70%, and the water-gas ratio is as high as 1.1. Due to the high water-gas ratio and CO content, the conversion load of the sulfur-resistant conversion system is increased, and the reaction depth is difficult to control. During the start-up process, the conversion reactor is very likely to overheat due to excessive reaction. Especially when starting at a lower load, the overheating problem of the converter is more serious. In actual production, the maximum temperature of the converter of some enterprises reaches 510°C, and the method of increasing the steam pressure temperature is often adopted to solve it. The layered control reactor developed by Qingdao Lianxin provides a better choice to solve this problem.
