Production of Ethanol from Synthesis Gas Hysys Simulation: Production of Ethanol from Synthesis Gas Done by Group 4: Sara Al-Quhaim Mona Al-Khalaf Sara Al-Safi Noura Al-Dousari

Agenda: Introduction HYSYS Simulation Program Programming Ethanol into HYSYS Alternative separation units (The first flow sheet ) Discussion

Introduction: The objective of our project is to produce ethanol from the synthesis gas as a result of the rising price of petroleum-based ethylene which is being used earlier. Ethanol is being produced from syngas in a catalytic synthesis reaction from synthetic gas which could be produced from any carbon source.

The main feed is synthesis gas which contains (Hydrogen, Carbon monoxide, Carbon dioxide and Nitrogen). The main reactions are: CO+2H2 CH3OH 2CO+4H2 C2H5OH+H2O CO + 3H2 CH4 +H2O For higher alcohol nCO+2nH2 CnH(2n+1)OH+(n-1)H2O 6H2+2CO2 CH3CH2OH+3H2O And water shift reaction

The final products which are : Methanol Propanol Ethanol (main)

In this section SRI present a speculative design for an alternative process to produce Ethanol from synthesis gas. The process uses a copper-cobalt catalyst and is in many ways similar to Methanol synthesis.

HYSYS Simulation Program: The goal of HYSYS program is to provide you with the capability to design an entire process as completely and accurately as possible. HYSYS is a modeling and analysis tool in the Unit Operations Laboratory of the chemical engineering program.

Programming Ethanol into HYSYS The plant is designed to produce ethanol as the principle product. ASSUMPTION: - Since gasoline is not present in HYSYS component, we used benzene instead of gasoline. - we mixed between iso-alcohol and normal alcohols and present them together as normal alcohols.

Cont. Assumption: - We create ten reactions which involve reaction of methane, ethanol and higher alcohols (C2-C7) from synthesis gas. - We considered set 1 as active reactions of methanol, ethanol and propanol and set the other reactions inactive.

Alternative separation units The first flow sheet

What is wrong with this flow sheet 1- There is losses in propanol and the purity of propanol final stream was 35 wt% 2- In the distillation column T-102 we took the bottom product and this is wrong because its contain almost water and the alcohol recycled to the column this column was based on the flow sheet that is given which has an izotropeic miture of ethanol-water

When we add component splitter and recycle

Comparison between flow sheets

Lowering the cost with less equipment

So its better to use thermal separation by component splitter that is work as flash separator

Discussion: UNIQUAC fluid package, because it is the only package that increases the amount of water resulted in the process. We considered only 3 reactions from a set of 10 reactions. We combine two reaction of ethanol in one reaction which is reaction 2 at HYSYS.

The combine reaction: 10H2 + 2CO +2CO2 4H2O + 2C2H5 OH We ignore higher alcohols C4-C7 in order to control the ten reactions conversion.

Discussion: Because there are no higher alcohols present from the reactor product, we ignore the liquid liquid extractor C-203. We collect high amount of ethanol, methanol and propanol in which there are above 90% recovery.

Discussion: No azeotrope in our plant, Because the composition of azeotropic ethanol water system is 94 wt%, and in our plant the composition was 47% which is less than the azeotrope composition

Discussion: To separate azeotrope mixture, benzene is used to break the bond between alcohol and water. Because there is no azeotrope in our plant, we ignore the benzene.

Discussion: In distillation column C-201, by trial and error to the reflux ratio we get that this distillation column is work currently at higher reflux ratio of 90 to separate methanol from alcohol and water.

Thank You