MULTITUBULAR REACTOR DESIGN FOR WASTE MINIMIZATION

Conventional multitubular reactors (MTR) are designed with baffles to promote cross flow. They may be operated either co- or counter-current ly but neither of these give the highest performance because it is not possible to ensure the best temperature distribution throughout the s ystem. This work considers two alternative reactor configurations to t ry to overcome this so as to minimize production of by-products. One i s based on the use of co-current cooling in the inlet zone with counte r-current flow at the exit where the reaction rates are lower. Such an arrangement makes it possible to match the temperature distribution t o reactant feed conditions so that there is a consistent selective con version in each of the tubes. An alternative is to use a windowless ba ffled reactor, with multi-feed of the coolant. This enables close cont rol of the temperature profile along the reactor length to be achieved by controlling the coolant conditions in each chamber, together with flow rate. Both arrangements enable very high performance in terms of selectivity with minimum waste production.