WASTE REDUCTION THROUGH MULTICOMPONENT MASS-EXCHANGE NETWORK SYNTHESIS

We have developed the ''mass exchange network (MEN)'' synthesis concep t to provide solutions for waste-minimization problems. Often, waste r eduction problems require the removal of multiple toxic species from p lant streams. Aside from the transfer of multiple chemical species mul ticomponent problems also encompasses simultaneous heat and mass excha nge. To address this problem, we employ the recently proposed ''State Space Approach.'' The State Space Approach decomposes the network synt hesis problem into the evaluation of an operator-where the actual unit operations abe defined, and the distribution network-which contains a ll the flows to and from the operator. The entire network is optimized simultaneously. The use of distinct subnetworks for the flows and uni t operations gives complete flexibility to choose over all possible co nfigurations. The proposed approach is illustrated through as example from recycle-reuse tasks: the removal of nitrogenous compounds from th e waste streams of a fertilizer plant.