The Research And Realizing On Lanzhou-Gasoline On-line Blending Based On Controlling Of DCS

Auto gasoline blending around the world is mainly tank-type ratio blending and online pipe blending. The biggest disadvantage of tank ratio blending is that requires more oil tanks, and has to know octane number and quality targets of the gasoline for confirming formulas of blending proportions. As complex blending effect existed among gasoline components, it is very hard to predict quality targets of octane number for finished gasoline blending. Therefore, lead to requently blending, efficiency decreasing and cycle extending. For enhancing auto gasoline blending ligibility ratio, increase proportion of gasoline components with high octane number is usually used in formula development. As a result, octane number of the finished gasoline is much higher than those of required by quality targets, then quality surplus and higher blending cost being occurred.Gasoline blending is a process to blend more than two types of gasoline components together and to analyze it according to different experience ratio. Octane number of different components is not linearity relationship with the total octane number after blending. As complex blending effect existed among gasoline components, it is hard to predict and control quality target of octane number for finished gasoline. Therefore, it is impossible to achieve high blending eligibility ratio once by only relying on experience for gasoline production, and to result in frequent blending or product quality surplus.The most economic and reliable method for solving above mentioned problems is to use the advanced online pipe optimizing control blending. That is to collect more than two types of gasoline components into one pipe through different component pipelines, then flow into finished gasoline tank after blending in a static blending container. In order to control flow quantity of every component and to collect blending data during gasoline online pipe blending, the equipments are used for system controls, including infrared isooctane analyzing, component flow controlling, backup pressure controlling, automatic feeding and pump frequency conversion. Software of gasoline online pipe blending Ditrbute Controlling System control system is mainly imported from USHoneywell. Through gasoline online pipeline blending, gasoline blending achieves critical blending, not only reduce quality waste and blending cost greatly but also enhance the blending efficiency and create excellent economic benefit.