MVC: A User-Based On-Line Optimal Control System for Small Gas Processing and Treating Plants. Development and Results for Lean Oil Absorption/Desorption Modules. Topical Report, January-November 1991.

摘要

The two phase project involved the development and field validation of an optimal process control system for lean oil absorption/desorption gas processing plants. Phase 1 consisted of a field survey and software module development activity for the control modules. Phase 2 consisted of the field validation of the total package. The software package (called MVC) is a modular, on-line, advanced control system designed for gas processing and treating facilities. MVC is 386/486 PC-based and relatively inexpensive. Software modules (standarized self-contained process software packages for specific process units) were developed for Refrigerated Lean Oil Absorption and Lean Oil Recovery (Desorption) and were installed for field performance validation at ARCO's Denver City, Texas gas processing plant. Each module consists of process simulations, feedforward control equations, feedback trim equations and adaptive control features including re-linearization (for simulation equation coefficients) and drift factor equations (to correct for the normal drifting of on-line analyzers). The process optimization uses an economic module containing prices and operating costs which forms the basis of the profit maximization. The project duration was 10 1/2 months and was completed in December, 1991. Current process control optimization is expensive and generally infeasible for small and mid-sized gas plants. MVC is designed to gain more than 90% of the benefits of optimized advanced control while running for over 90% of the available service time. MVC utilizes standardized software algorithms with coefficients tailored to specific process units. MVC will give producers the economic incentive to process more gas and thus increase the availability to consumers of both natural gas and natural gas liquids at lower prices.