Operational Optimization And Retrofit Design Of Centrifugal Pump Network

Centrifugal pump is a general equipment in chemical engineering.It is of great significance for researchers to study commercial centrifugal pump network design and operational optimization problem,of which the challenge is solving mixed-integer nonlinear programming caused by equipment distribution,on/off decision and frequency adjusting,whatever in operating,design and retrofit cases.In this thesis,centrifugal pump network operational and retrofit design problems are established.The problems are solved with not only heuristic rules for industrial purpose,but also mathematical programming method for global optima searching.The results are supposed to support both theoretical research and industrial applications.The main works are listed as following three aspects,(1)Choose adequate performance equations and interpolate pump curves after cutting and changing frequency by affinity laws.Basic model and database of equipments are given.Basic objective function,equality and inequality constraints are provided as well.(2)Centrifugal pump network operational optimization based on stepwise design.Flowrate and head feasible region is searched with specified pump network structure of one industrial cooling water system.A series of single-objective optimization problems are solved with both heuristics rules and mathematical programming method,taking on/off and frequencies as decision variables.Multi-objective optimization problems are solved with both Pareto frontier curve analysis and objective elimination.(3)Pump network retrofit based on synchronous design.The work focused on distributed demands of cooling water system,changed energy supplying and using end simultaneously.Number and location of main and booster pumps are optimized synchronously.Objective function is set as the minimum total annual cost.Optimal pump locations and configurations are decided based on industrial centrifugal pump inventory,using both heuristics method and mathematical programming method.It is shown that solution obtained by mathematical programming method is better than heuristics method when demands distribution is more complex.Flexibility analysis are conducted with both stepwise and synchronous design strategies.The effects of equipment parameters are also discussed.