Process Integration Accounting Fouling in Heat Exchanger Network: A Case Study of Crude Oil Distillation Retrofit

• Main Authors: Mikhail Vasilyev, Stanislav Boldyryev
• Format: Article
• Language: English
• Published: AIDIC Servizi S.r.l. 2018-08-01
• Series: Chemical Engineering Transactions
• Online Access: https://www.cetjournal.it/index.php/cet/article/view/789

This paper presents the approach to predict the future performance of a heat exchanger network based on Pinch retrofit design and detailed historical performance of the unit to improve the operation efficiency, save an energy and increase a throughput. The main input is a finding of a profitable solution of heat exchanger network based on Pinch Analysis, fouling predictive management and a start-up and shut-down time. The approach demonstrates the importance of a dynamic assessment of the retrofit design and operation modes. The case study was developed for crude oil distillation unit with annual capacity of 6 Mt. Dynamic fouling models were built to assist with designing and revamping of heat exchanger network, to reduce the fouling and increase the throughput. Rigorous modelling of refinery heat exchangers network and Pinch Analysis were executed to achieve increased throughput, reduce operation cost and harmful emissions. A new heat exchangers network with improved operation conditions predicting efficient exchanger cleaning schedules under various economic and operational constraints was obtained. The calculations use an HTRI shell-and-tube heat exchanger models, operation data, properties of crude oil and cleaning schedule. Process Integration steps were done by HILECT software and new operation schedule of efficient heat exchangers network was created by HTRI software. The strategy and recommendations for the optimal operation of the retrofitted network were proposed taking into account the economic and process constraints such as exchanger by-passes, operation budget, furnace duty and pumping limit.