延迟焦化废水预处理技术研究

Study on the Pretreatment of Waste-Water from Delayed Coking

针对锦州石化公司炼油厂焦化废水冲击污水场，使浮选、生化装置不能正常运转这一问题进行了预处理研究。分析了焦化废水的水质指标，通过对自由沉降和离心分离小试试验结果的比较，考察了加热离心分离法处理炼油厂含油焦化废水脱除固体颗粒的效果。结果表明，采用直径为１００ ｍ ｍ 、高２ ５００ ｍ ｍ 的自由沉降柱，经１２０ ｍｉｎ 的自由沉降可使油含量由２８２ ｍｇ／Ｌ 降至４３ ｍｇ／Ｌ；固体含量由３４１ｍｇ／Ｌ 降至１０９ ｍｇ／Ｌ；说明具有较好的处理效果。离心机转速在２ ５００ ｒ／ ｍｉｎ 、时间１ ～２ ｍｉｎ 的条件下，通过加热离心分离法将大大改善含油焦化废水的脱水和脱固性能，在加热到６０ ～８０ ℃，７５ ％ 以上的固体颗粒可被脱除。完全能够满足炼油厂污水场浮选。

Aiming at solving the problem that the floatation and biochemical purification units on sewage workshop, can not work well because of the impact of coking wastewater from refinery of Jinzhou petrochemical cooptration the pretreatment technology has been studied. The quality index of coking wastewater was analyzed. Through the comparison of the experimental results between naturals ettlement and centrifugal separation, the efficiency of removal of the solid grain from coking wastewater containing oil in refinery by heating centrifugal separation was investigated. The results show that the oil and solid content can effectively reduced from 281 to 43 mg/L, 341 to 109 mg/L respectively, after having freedom settled for 120 min in a settling column with 100 mm diameter and 2 500 mm height. This indicates that the removal efficiency is significant. The performance of dewatering and removal of the solid of coking wastewater containing oil will be greatly improved by heating centrifugal separation under the conditions of 2 500 r/min in rotating speed and 1～2 min in resting time. When the temperature rises to 60～80℃, more than 75% of the solid grain can be removed from coking wastewater as to meet the requirement for input of floatation and biochemical purification unit of oil refinery.