Research On Dynamic Scheduling Method For Reverse Osmosis Seawater Desalination System

Fresh water has become an important resource for the development of national economy.With the rapid development of economy,the demand for fresh water resources has become larger and larger.In order to solve the water shortage problem effectively in coastal areas,sea water desalination has become one of the most effective methods.Reverse osmosis seawater desalination is a typical application of seawater desalination technology.The reverse osmosis seawater desalination system is composed of reverse osmosis membrane,high pressure pump and energy recovery device,and so on.With the increasing scale of the whole desalination system,it is necessary to make a reasonable plan for the optimal operation of the whole sea water desalination system in order to reduce the cost of the sea water desalination.This paper mainly studied the optimization scheduling problem under municipal water supply prediction error and water production unit random failure,the main research results are as follows:(1)The typical reverse osmosis seawater desalination system is presented;the principle of reverse osmosis seawater desalination reverse osmosis membrane module was introduced and its operating unit model was established;the operating cost of reverse osmosis seawater desalination is analyzed,the cost objective function is established,and the constraint conditions are given,which provides a basis for the optimal operation of reverse osmosis seawater desalination project.(2)The basic principles and steps of municipal water supply forecast are introduced,and the trend and periodicity of the municipal water supply are pointed out,and the factors affecting the municipal water supply is analyzed.Three municipal water supply forecasting models are established,and the combined model is predicted by the evaluation indicators to be more accurate,which provides accurate forecasting data for the optimal operation.The influencing factors such as in fluent water temperature,water salinity,energy recovery rate and so on were analyzed by using the simulation software of Hydean Reverse Osmosis Design Software.(3)The influence on the system operation cost by water consumption prediction error and stochastic failure of the unit is studied,and the chance constrained programming model is established,and the model is solved by the particle swarm optimization algorithm using Monte Carlo simulation.Simulation results show that the proposed algorithm can solve the model in this paper.At the same time,the influence of the inertia weight factor on the performance of the model and the influence of the different unit maintenance plan on the optimal scheduling are studied.Finally,the effect of the redundancy technique and the stochastic simulation technique on the small variables are compared.The latter is better than the former in the cost reducing and is worse in the time consuming.(4)Based on the theory of optimal scheduling,the optimal scheduling software for large scale reverse osmosis seawater desalination system is designed and implemented,which is composed of water forecast module,equipment maintenance module and optimized operation module.At last,the article is summarized and several problems,which are need to be studied in the future,are pointed out.