Problems of adopting coal tar in heater

In recent years, Weihui Pump Station in Xinxiang Oil Transportation Company has changed crude oil to coal tar as heater's fuel, however, some problems such as low thermal efficiency, burner abrasion, fan-coil coking and heating surface scaling have been found. Analysis results about the combustion characteristics of coal tar show that ash and water content are higher compared with crude oil, while the content of combustible component is lower. Moreover, low heat value and higher flash point of coal tar result in difficult ignition and unstable burning. Correction calculation on heater temperature, exhausting temperature, thermal efficiency, thermal loss and other parameters is carried out. The result shows that heat transfer conditions of heater turns worse, while thermal loss of flue exhausting and incomplete combustion are increased, so the thermal efficiency of heater is obviously declined. Thus, coal tar content controlling, special burner for coal tar and increasing heating surface are keys to solve these problems.