# Co-Production of Hydrogen and Methanol Using Fuel Mix Systems: Technical and Economic Assessment
## 2 Development of Simulation Model  
In this work, Aspen Plus V11 was used as the process simulator to develop the models for the simultaneous methanol and H\({}_{2}\) production. The Peng Robinson with Boston Mathias (PR-BM) equation of state was employed as the thermodynamic package for the calculation of physical properties. As the composition of fossil fuels is not consistent globally, the coal and biomass used in this study were modelled as unconventional components in Aspen Plus. Proximate, ultimate and sulfanal analyses were taken from the experimental results to specify the composition and heating values of the feedstock. Table 1 represents the modelling units of all processes developed in Aspen Plus along with their operation conditions. \begin{table}
\begin{tabular}{c c} \hline \hline
**Process Section** & **Simulation Unit/Conditions** \\ \hline \multirow{4}{*}{Gasification} & Model: RGIBBS \\  & Temperature: 1350-1370 \({}^{\circ}\)C \\  & Pressure: 56 bar \\  & Feed flow rate = 62.01 kg/s (coal) + \\  & 6.2 kg/s (biomass) \\ \hline \multirow{4}{*}{Reformer} & Model: RGIBBS \\  & Temperature: 900 \({}^{\circ}\)C \\ \cline{1-1}  & Pressure: 32 bar \\ \cline{1-1}  & Feed flow rate: 5.5 kg/s (natural gas) \\ \cline{1-1}  & H\({}_{2}\)O\(\cdot\)CH\({}_{4}\) = 3:1 \\ \cline{1-1}  & Ni-based catalyst \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Design parameter and modelling approach. Case 1: Coal and Biomass-Based Model for the Simultaneous Methanol and Hydrogen Production (CBMH Process)  
Case 1 is considered the base case model for producing methanol and hydrogen from coal and biomass feedstocks. as represented in Figure 1. The process starts with coal and biomass blending at a weight ratio of 90:10%. The blend feed for the gasifier, which is a mixture of coal and biomass, enters the entrained flow gasifier at 56 bar pressure. A controlled amount of high-purity oxygen (95 vol. %) also enters at the top of the gasifier, which partially oxidizes the feed stream to produce raw syngas. The syngas is then passed through a series of radiant and convective heat exchangers to reduce the temperature to 20 \({}^{\circ}\)C, which is further reduced to \(-\)35 \({}^{\circ}\)C in the AGR unit to remove H\({}_{2}\)S and CO\({}_{2}\). The syngas is then pre-heated to 200 \({}^{\circ}\)C and fed to the methanol synthesis unit to produce methanol. As the conversion of syngas to methanol is not complete, the syngas is fed to the WGS unit, where it reacts with steam to convert the CO in the syngas to H\({}_{2}\). The mixture of H\({}_{2}\) and CO\({}_{2}\) is then fed into the CO\({}_{2}\) removal unit to capture CO\({}_{2}\), and pure H\({}_{2}\) is recovered and sent to the storage section. \begin{table}
\begin{tabular}{c c} \hline
**Process Section** & **Simulation Unit/Conditions** \\ \hline \multirow{4}{*}{Shift Conversion (WGS)} & Model: REquil Reactor \\  & 2 Adiabatic reactors \\  & Co-Mo based catalyst for sour shift \\  & Steam/CO: \(\sim\)2.2 \\  & CO conversion \(\sim\)99\% \\ \hline \multirow{4}{*}{Air Separation Unit (ASU)} & Model: HeatX, Compr \\  & O\({}_{2}\) purity: 95\% (vol) \\  & Energy consumption: 0.25 kW\({}_{\text{h}}\)/kg \\ \hline \multirow{4}{*}{AGR Unit} & Model: Flash, RadFrac \\  & H\({}_{2}\)S Removal = 100 ppbv \\  & CO\({}_{2}\) Removal = 90\% \\  & Rectisol Process) Temp/Pressure = \(-\)33 \({}^{\circ}\)C/5.5 MPa \\ \hline \multirow{4}{*}{Methanol Reactor} & RGibbs (Reactor) \\  & Cu/ZnO/Al2O3 based catalyst \\ \cline{1-1}  & Temp/Pressure = 200 \({}^{\circ}\)C/5.5 MPa \\ \hline \multirow{2}{*}{Heat Exchangers} & Heater, HeatX, MHeatX \\  & \(\Delta\)T\({}_{\text{min}}\) = 10 \({}^{\circ}\)C \\ \hline \end{tabular}
\end{table} 
Table 1: _Cont._  
Figure 1: Process model for converting coal and biomass to methanol and hydrogen. Case 2: Co-Production of Methanol and Hydrogen from Gasification and Reformation Models Using Three Fuels (Coal, Biomass and Natural Gas)--CBNMH Process  
Case 2 represents the new model and represents the modifications made in case 1.