Energetic Analysis of a Crude Distillation Plant: a Case Study
Advancing the chemical engineering fundamentals
Distillation, Absorption & Extraction - II (T2-10b)
Keywords: Crude Distillation, Energy demands, Thermal Integration
Crude Distillation Unit is an energy and power intensive process and contributes significantly to the energy demand of the refinery, as well as to its greenhouse gas emissions.
This work present an industrial case study which deals with a energetic analysis of an existing crude oil distillation plant to study energy and efficiencies for system analysis, performance evaluation and optimization.
The existing plant (the crude distillation tower and the vacuum column) was first simulated by using a commercial software and the field data of compositions flow rates and temperatures, obtaining a good model of the existing plant.
A three parameters continuous distribution model was utilized to characterise all the streams of the plant, and the parameters were calculated from the laboratory TBP data. The results obtained were compared with the plant data in terms of flow rates and product quality utilizing the ASTM D-86 curves and a good agreement was obtained.
The model was then used in an optimization-based approach to optimise the process conditions of the existing plant in order to reduce its energy demands. The main topping column, along with the sidestrippers, and the vacuum unit were firstly considered as a sequence of simple columns, and all the possible sequences for the separation were identified, according to the literature. The simulation of all the sequences was implemented and the energy demands were obtained. The different sequences were ranked on the basis of the energy requirements, and the best one was then reconverted to a thermally coupled sequence constituted by two main columns with side units.
The results allowed to identify scope for energy savings, which can be obtained by internally heat integration as well as by integrating a gas turbine.
Presented Monday 17, 15:20 to 15:40, in session Distillation, Absorption & Extraction - III (T2-10b).
