Energy Efficient Styrene Process

Design and Plantwide Control

Alexandre C. Dimian, Costin-Sorin Bildea

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The paper deals with conceptual design and simulation of an energy efficient process for manufacturing styrene by ethylbenzene dehydrogenation in adiabatic reactors using superheated steam as inert. A high performance catalyst is employed with selectivity of 95% at conversion of 70%. An innovative solution leads to a spectacular energy saving. The idea is running the steam generation under vacuum, followed by mechanical vapor recompression (MVR). The resulting pressure allows matching the temperature-enthalpy profiles of cold and hot streams in an evaporation/condensation zone that concentrates 40% from the hot energy input. In addition, effective heat transfer is ensured by high transfer coefficients. An efficient network of five feed-effluent-heat-exchanger (FEHE) units diminishes the utility consumption by 73% with respect to the base-case. The economic analysis demonstrates that the cost of energy dominates over the cost of equipment. Despite the investment in the compressor, the MVR alternative brings a reduction in the total annual cost by 36%. The feasibility of the proposed solution is validated by dynamic simulation. The plantwide control adopts the strategy of keeping constant the flow rate of ethylbenzene to the reaction section proportional to the required production rate. The process can handle disturbances of ±10% in throughput while keeping the purity of styrene over 99.5%.

Original languageEnglish
Pages (from-to)4890-4905
Number of pages16
JournalIndustrial and Engineering Chemistry Research
Volume58
Issue number12
DOIs
Publication statusPublished - Mar 27 2019

Fingerprint

Styrene
Process design
Ethylbenzene
Steam
Vapors
Costs
Catalyst selectivity
Economic analysis
Dehydrogenation
Conceptual design
Heat exchangers
Compressors
Effluents
Condensation
Enthalpy
Energy conservation
Evaporation
Flow rate
Throughput
Vacuum

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Cite this

Energy Efficient Styrene Process : Design and Plantwide Control. / Dimian, Alexandre C.; Bildea, Costin-Sorin.

In: Industrial and Engineering Chemistry Research, Vol. 58, No. 12, 27.03.2019, p. 4890-4905.

Research output: Contribution to journalArticle

Dimian, Alexandre C. ; Bildea, Costin-Sorin. / Energy Efficient Styrene Process : Design and Plantwide Control. In: Industrial and Engineering Chemistry Research. 2019 ; Vol. 58, No. 12. pp. 4890-4905.
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