Abstract:

A typical refinery consists of the production system and the utility system. Traditional refinery-wide optimization is carried out in a sequential process which not only misses opportunities of increasing the overall refinery economic margin, but also leads to the economic losses of extra fuel gas vent and environmental cost of harmful gas emission. A novel integrated approach which couples the production system and the utility system is presented and optimized simultaneously in a refinery-wide mixed-integer nonlinear programming (MINLP) model. The production unit energy consumption model is introduced by considering the relationship of energy consumption, unit throughput, and operation modes. Material balance of intermediate product such as fuel gas and fuel oil and energy generation and consumption balance of different utilities are considered to improve energy utilization. A real industrial example is investigated to demonstrate the performance of the proposed method which leads to sharp decrease in refinery-wide operation cost and a significant improvement in energy saving and emission reducing.

Key words: process systems, integration, optimization, energy system, utility, energy saving, emission reduction

摘要：

炼油企业通常由物料生产系统与能量系统组成。传统的企业生产计划优化通常以生产系统物流优化为主, 能量系统基于物料生产优化结果进行产能优化以满足企业级能源供需平衡。此种优化方法不仅压缩了企业整体优化空间并且降低了燃料油与瓦斯等中间产品的利用率。基于装置能耗模型与能源供需以及中间产品的产耗质量平衡关系, 建立炼油企业生产系统与能源系统的集成优化模型, 通过求解MINLP模型进而实现企业生产物流与能流的集成优化。案例实践表明, 相较于传统分步优化方法, 集成优化方法不仅有效降低了全厂的生产成本, 并且实现了生产的节能减排。

关键词: 过程系统, 集成, 优化, 能源系统, 公用工程, 节能, 减排