利用新技术新方法提高裂解炉热效率

裂解炉是乙烯装置耗能大户,具有物料量大、停留时间短、使用温度高、设备表面积大等特点,采取适当措施提高其热效率很有必要。清除对流段管束表面积灰可采取蒸汽吹灰、水力吹灰、振动(爆破法)、钢珠除灰及声波吹灰、干冰清洗等物理方法。其中声波吹灰随着其噪声和辐射问题的解决,将具有广泛发展前景;干冰清洗技术也具有一定效果,但需作业人员有较强的责任心,保证各个角落处理到位。此外,还可以采用化学清洗、除灰剂技术等化学方法。做好辐射段炉墙的隔热保温工作可减少裂解炉辐射段热损失。将高效隔热耐火涂料喷涂在辐射段内墙表面,可阻止热量向外传导,同时也可将热量返回至炉膛。对燃烧空气进行预热可改善燃烧条件,提高燃烧效率,降低烟气排放量和排放温度。可以采用过剩低压蒸汽或急冷水余热加热空气,以12×104t/a裂解炉为例,利用急冷水余热加热空气至75～80℃,单台炉每年可节约燃料1000t左右。同时,工艺操作和生产调优对于提高裂解炉热效率也十分重要。

Improve Thermal Efficiency of Cracking Furnaces Using New Technology and New Methods

The cracking furnace is the major energy consumer in an ethylene unit and characterized by large volume of raw material needed,short residence time,high working temperature and large surface area.It is thus very necessary to take appropriate measures to raise the furnace's thermal efficiency.Physical methods can be used to remove the soot deposited at the surface of tubes of the convection section such as steam blowing method,hydraulic blowing method,vibration (blasting) method,steel ball soot removing meth...