* Pooling problem (Haverly, 1978) * Case 3 VARIABLES x product stream from mixer x y product stream from mixer y A feed flowrate B feed flowrate cx flowrate of stream from splitter to mixer x cy flowrate of stream from splitter to mixer y p sulfur content of streams leaving pool Px flowrate of stream from pool to mixer x Py flowrate of stream from pool to mixer y objval objective function variable; FREE VARIABLES objval; EQUATIONS f Objective function g1 g2 g3 g4 g5 g6 ; f .. objval =e= 9*x + 15*y - 6*A - 13*B - 10*cx - 10*cy; g1 .. Px + Py - A - B =e= 0; g2 .. x - Px - cx =e= 0; g3 .. y - Py - cy =e= 0; g4 .. 2 * cx - 2.5 * x + p * Px =l= 0; g5 .. 2 * cy - 1.5 * y + p * Py =l= 0; g6 .. -3 * A - B + p * Px + p * Py =e= 0; * Bounds x.LO = 0; x.UP = 100; y.LO = 0; y.UP = 200; A.LO = 0; A.UP = 500; B.LO = 0; B.UP = 500; cx.LO = 0; cx.UP = 500; cy.LO = 0; cy.UP = 500; p.LO = 0; p.UP = 500; Px.LO = 0; Px.UP = 500; Py.LO = 0; Py.UP = 500; * Starting point (global solution) * x.L = 0; y.L = 200; A.L = 50; B.L = 150; cx.L = 0; * cy.L = 0; Px.L = 0; Py.L = 200; p.L = 1.5; MODEL test /ALL/; SOLVE test USING NLP MAXIMIZING objval;