Design of heat-integrated columns: Industrial practice

Abstract

Heat integration of distillation columns offers a significant potential to reduce energy costs and carbon footprint in process plants. The conceptual design for heat integration is straightforward: candidate columns may be identified simply by evaluation of the vapor pressure curves of their top and bottoms products. Once the energy and cost savings potential is estimated, the easy part is over and the real challenge for the designers begins. Successful implementation of heat integration will have a strong impact on the overall plant setup intensifying interactions between equipment design, plant layout, instrumentation, process control, and safety concept. In order to master this increased project complexity, the design team needs to begin to tackle these questions in early project stages and find sustainable solutions in the pre-basic engineering phase already.The paper outlines a useful methodology for the successful design of heat-integrated column systems. The guidelines provided help the practitioner to anticipate and solve typical problems, avoid pitfalls and find practical solutions resulting in cost-effective, reliable designs near the energy optimum. The methodology has been successfully applied in industrial practice and is demonstrated using a recent project as an example.