Study On Assistant Design And Optimization Of Sedimentation Tanks

For a long time, most of designs of water supply and sewerage have been conducted manually. Fast, effective and intellectualized design is the key to reduction of the work load. Another important field is the optimal design of secondary sedimentation tank by adopting scientific and reasonable mathematical model under the premise of keeping sedimentation efficiency. In this dissertation, a system for quick design of sedimentation tank is developed and the problem of optimal design of secondary sedimentation tank is also investigated.Sedimentation tank design system (STDS) developed with Visual Basic program language, which comes out of the engineering design practice, supplies the designer a quick and powerful tool. The system has five function modules which are data input, computation, data output, data saving and printing. In the system, many design criterions for building and water supply and sewerage are supplied. Besides, the system also includes lots of design data, master drawings, simulation models, which may give designers more engineering information about sedimentation tanks. Some useful extended modules are e-mail sending and receiving, network querying, etc.This paper also studies the optimal design of secondary sedimentation tank under two premises. One is keeping the efficiency of bioreactor tank and the secondary sedimentation tank. The other is achieving the maximum synthesis efficiency of two kinds of tanks. By BP neural network performing nonlinear mapping and combining regression orthogonal, the sedimentation tank cost functions are set up and the objectives are also provided. The parameters are confined in the range according to the criterion, so the integrated optimal design models are set up. The optimum solutions are obtained with Matlab'optimization toolboxes.This paper takes the sedimentation tank with circumferential inlet as the example. The optimum design model is established according to the criterion, the objective of which is to minimize the cost. The optimum solution obtained by using Matlab'optimization tool boxes indicates that construction expense saves 9.8% compared with the conventional design. Meanwhile, the influence of design parameters are also considered, which may give some references to the designers.