连续重整装置再生器约翰逊内网开裂的原因分析及优化措施

中国石化天津分公司1.0 Mt/a连续重整装置再生器约翰逊内网出现开裂，原因是再生器内网顶部焊接区域存在应力，操作过程温度梯度变化大，并且内网顶部区域温度随催化剂周期性间断流动而交替变化致使出现金属疲劳。通过降低再生烧焦气中氧含量，使位于内网上部的催化剂在相对缓和的条件下进行烧炭，同时严格控制原料终馏点不高于173 ℃，提高重整反应氢油摩尔比至2.5，优化调整后，待生催化剂积炭量由5.1%降至4.8%，烧炭区峰值温度由568 ℃降至552 ℃，有利于再生器内网的长周期稳定运行。

CAUSE ANALYSIS AND MEASURES OF JOHNSON SCREEN CRACKING IN REGENERATOR OF CONTINUOUS REFORMER AND OPTIMUM MEASURES

The cracking of the Johnson inner screen in the regenerator of a 1M/a continuous catalytic reforming unit of SINOPEC Tianjin Refinery Company was caused by the stress existing on the top welding area of the Johnson inner screen and the metal fatigue caused by the periodic discontinuous flow of catalyst. By properly adjusting oxygen content in the regenerated flue gas，the coke on the catalyst in the upper inner screen burned under relative moderated conditions. Meantime, the final boiling point of raw material was strictly controlled not higher than 173 ℃ and the hydrogen/hydrocarbon mol ratio at 2.5. As a result，the coke on the catalyst was decreased from 5.1% to 4.8%，and the peak of temperature in coke burning zone decreased from 568 ℃ to 552 ℃，which is beneficial to long term stable operation of the Johnson inner screen.