CH4/N2气氛对重油热裂解气体产率及组成的影响

延迟焦化工艺中将焦化炉注蒸汽改为注干气，可以避免因注入水蒸气而带来的含硫污水污染。为考察注入干气对装置气体产率及组成的影响，以金陵减渣、济南减渣、青岛减渣为研究对象，在CH4、N2气氛下分别进行热反应实验，分析其热裂解气体产率及组成。结果表明：在反应条件相同时，与N2气氛相比，CH4气氛下的气体产率较低，且裂解气中C1体积分数降低1~2百分点。此外，在反应时间相同时，反应温度升高后，两种气氛下气体产率差值缩小；随油气分压增加，两种气氛下气体产率差值亦缩小。

EFFECT OF CH4/N2 ATMOSPHERE ON THE YIELD AND COMPOSITION OF GAS FROM HEAVY OIL THERMOLYSIS

In delayed coking process, water vapor is injected into the heater as a dilution medium to suppress coke formation, yet sour water pollution is generated, now dry gas is proposed to use as an alternative dilution medium to eliminate the sour water pollution. In order to investigate the effect of dry gas on the yield and compositions of gas formed by thermolysis, thermal reaction experiments are conducted under the atmosphere of CH4 and N2 using vacuum residues from Jinling, Jinan and Qingdao as feeds, the gas yields and compositions are measured. Results indicate that under the same reaction conditions, compared with in N2 atmosphere the gas yield in CH4 atmosphere is lower and the volume fraction of methane in cracking gas is 1-2 percentage point lower. Furthermore, under same reaction time, the difference of gas yields between these two conditions decreases as the reaction temperature increasing, as well as decrease with the increase of oil vapor partial pressure.