**Comparison of Equilibrium-Stage and Rate-Based Models of a Packed Column for Tar Absorption Using Vegetable Oil**

#### **Adel Almoslh \*, Falah Alobaid, Christian Heinze and Bernd Epple**

Institut Energiesysteme und Energietechnik, Technische Universität Darmstadt, Otto-Berndt-Straße 2, 64287 Darmstadt, Germany; falah.alobaid@est.tu-darmstadt.de (F.A.); christian.heinze@est.tu-darmstadt.de (C.H.); bernd.epple@est.tu-darmstadt.de (B.E.)

**\*** Correspondence: adel.almoslh@est.tu-darmstadt.de; Tel.: +49-6151/16-23004; Fax: +49-(0)-6151/16-22690

Received: 18 February 2020; Accepted: 18 March 2020; Published: 30 March 2020

**Abstract:** In this study two mathematical models, rate-based and equilibrium-stage models in Aspen Plus process simulator, were used to simulate the tar absorption processes using soybean oil as a solvent in a research lab-scale experiment. The matching between simulation results and experimental data shows a good agreement. The simulation results predicted by the rate-based model show a higher level of agreemen<sup>t</sup> than the equilibrium model compared with the experimental data. Analysis study of tar absorption process was carried out which revealed the e ffect of temperature and flow rate on the soybean oil, and height-packed bed on tar removal e fficiency. The methodology of selecting the optimum (most economical) operation conditions has also been performed in this study.

**Keywords:** gasification; tar absorption; process simulation; validation study; sensitivity analyses
