Introduction

 

Utility account for many of the yearly operating costs for a chemical plant. These utility costs can include electricity required for various pieces of equipment, cooling water, steam, and fuel needed to run the plant. Through heat integration these costs can be minimized. The basic principle is to utilize as many streams within the plant to heat exchange streams elsewhere in the plant.

In the base case process for acetone there are three streams that require some type of heat exchange. The only stream requiring heat is the stream entering the reactor. However, the stream exiting the reactor and the wastewater stream leaving the second condensing column both have to be cooled. Within the process there are also two condensers and two reboilers that are also available for heat exchange.

Both Hysys and Aspen were used in optimizing the base case model for acetone production. The optimized acetone plant consists of a network of seven heat exchangers that utilize both process streams as well as reboilers to perform the necessary heat exchange. There were few changes made to the base case for the sake of simplicity as well as efficiency. Only one minor change was made at the inlet to the separation process—the temperature was increased.