Optimal design of reverse-osmosis networks for wastewater treatment

An optimization study of reverse-osmosis networks (RON) for wastewater treatment has been carried out by describing the system as a nonconvex mixed-integer nonlinear problem (MINLP). A mixed-integer linear problem (MILP) is derived from the original nonlinear problem by the convex relaxation of the nonconvex terms in the MINLP to provide bounds for the global optimum. The MILP model is solved iteratively to supply different initial guesses for the nonconvex MINLP model. It is found that such a procedure is effective in finding local optimum solutions in reasonable time and overcoming possible convergence difficulties associated with MINLP local search methods. Examples of water desalination and wastewater treatment from the pulp and paper industry are considered as case studies to illustrate the proposed solution strategy.

[1]  Ignacio E. Grossmann,et al.  Global optimization for the synthesis of integrated water systems in chemical processes , 2006, Comput. Chem. Eng..

[2]  Hanif D. Sherali,et al.  A new reformulation-linearization technique for bilinear programming problems , 1992, J. Glob. Optim..

[3]  Mahmoud M. El-Halwagi,et al.  Optimal design and scheduling of flexible reverse osmosis networks , 1997 .

[4]  Mahmoud M. El-Halwagi.  Optimal Design of Membrane-Hybrid Systems for Waste Reduction , 1993 .

[5]  Juan M. Zamora,et al.  Superstructure Decomposition and Parametric Optimization Approach for the Synthesis of Distributed Wastewater Treatment Networks , 2004 .

[6]  Christodoulos A. Floudas,et al.  Global optimization of a combinatorially complex generalized pooling problem , 2006 .

[7]  T. Umeda,et al.  Optimal water allocation in a petroleum refinery , 1980 .

[8]  Franco Evangelista.  A short cut method for the design of reverse osmosis desalination plants , 1985 .

[9]  Antonis C. Kokossis,et al.  Wastewater minimisation of industrial systems using an integrated approach , 1998 .

[10]  Gintaras V. Reklaitis,et al.  A DECOMPOSITION HEURISTIC FOR SCHEDULING THE GENERAL BATCH CHEMICAL PLANT , 1997 .

[11]  Lloyd P. M. Johnston,et al.  Optimal design of reverse osmosis module networks , 2000 .

[12]  Garth P. McCormick,et al.  Computability of global solutions to factorable nonconvex programs: Part I — Convex underestimating problems , 1976, Math. Program..

[13]  Mahmoud M. El-Halwagi,et al.  Synthesis of reverse‐osmosis networks for waste reduction , 1992 .

[14]  Mahmoud M. El-Halwagi,et al.  Process integration technology review: background and applications in the chemical process industry , 2003 .

[15]  Chuei-Tin Chang,et al.  A Mathematical Programming Model for Water Usage and Treatment Network Design , 1999 .

[16]  I. Grossmann,et al.  Optimal Design of Distributed Wastewater Treatment Networks , 1998 .