Computer aided design of acetaldehyde plant with zero avoidable pollution

Abstract

Appreciable efforts have been expended in the manufacture of chemical products in such a way that pollution may be minimized and, if possible, even avoided. The conceptual design of such production plants involves an interplay between design and operational requirements, which attempt to balance non-commensurable objectives such as economics, safety health and environmental impact. If the environmental impact problem is not considered in the conceptual phase of the process development, there is a need to extensive end-of-pipe treatment of wastes which is always an expensive activity with negative economic effect. In this sense, in this work, a conceptual design of an acetaldehyde plant with zero avoidable pollution is presented. The proposed process is based on the oxidation of ethyl alcohol over FeMo catalyst. In order to obtain high performance operation (high conversion and complete selectivity) a non-conventional reactor design is proposed. The computer aided design involves the experimental conversion of ethanol to acetaldehyde, the reactor analysis through extensive simulation using specific computer simulation code. The separating problem and the whole plant analysis is made using the HYSIM commercial simulator. It is shown the great potential of the proposed process which permits very high conversion and complete selectivity leading to zero waste emission. The process methodology considered in this work involves since the experimental conversion of ethanol to acetaldehyde up to the proposition of a new reactor design, a set of separation units and the whole acetaldehyde plant simulation.