PTQ Q2 2026 Issue

Refinery SMR reactor optimisation

Net-zero carbon and heat-integration technologies enhance the performance of steam methane reformers, boosting hydrogen production and improving energy efficiency

Nabeel Ataimisch ZCT Solutions GmbH

T he optimisation of refinery steam methane reform - ing (SMR) reactors through the implementation of zero-carbon technologies and heat integration is cru- cial to improving efficiency and reducing carbon emissions in the refining process. By integrating these technologies, the refinery process can enhance the overall performance of SMR reactors, leading to increased hydrogen (H₂) pro - duction with lower energy consumption and reduced envi - ronmental impact. The energy integration of industrial SMR reactors is influ - enced by several key factors, such as lower fuel consumption and reduced greenhouse gas (GHG) emissions. Research points to the heat-loss recovery of SMR reactors into energy, which can reduce the fuel supplied in SMR units to enhance thermal performance and reduce natural gas consumption. To produce hydrogen in SMR units, the minimum tem - perature should be 800°C, in which natural gas/methane (CH₄) reacts with steam (H₂O) on the surface of a catalyst within temperature and pressure ranges of 800-1,300°C and 5.5-50 bar: CH₄ + H₂O ↔ CO + 3H₂ The reaction is strongly endothermic (ΔHSR = 206 kJ/mol). CH₄ + 2H₂O ↔ CO₂ + 4H₂ The reaction is endothermic (ΔHSR = 165 kJ/mol). These technologies provide heat-loss recovery for SMR reactors, which plays a crucial role in evaluating the opti - misation of the reactor and unit with their impact on SMR efficiency. Factors such as the composition of waste gases, hydrogen content, and flame characteristics significantly affect the reformer’s operation. This research examines heat loss from both the reformer and flue gas across a series of heat exchangers, which can lead to improved thermal effi - ciency, reduced natural gas usage, and increased synthesis gas production in SMR units. Process assessment methodology These findings highlight the importance of optimising the SMR reactor to reduce fuel consumption and modify opera - tional parameters to enhance the performance of industrial SMR reactors (see Figure 1 ). In operating conditions, the SMR reactor requires a temperature of approximately 1,000°C to produce hydro - gen. Natural gas and steam are reformed into hydrogen and carbon monoxide by the absorption of heat from the

reformer heating furnace. The thermal and chemical enthal - pies increase to 1.84 MJ/Nm³-H₂ and 3.88 MJ/Nm³-H₂, respectively.³ Nevertheless, the reformer’s heating furnace consumes enthalpies reaching 10.0 MJ/Nm³-H₂.³ This value is approximately equivalent to the enthalpy accepted from the heating furnace. Consequently, only 25.5% of the input enthalpy of the heating furnace is accepted in the form of chemical enthalpy by the reforming of methane. This is due to significant heat losses across each process when compared to the energy input by enthalpy and/or megajoules within each system.4 The respective percent - ages are 30.2%, 15.5%, 0.74%, 0.73%, and 0.31% in the heating furnace, the combination boiler, the water pre - heater, the degasifier, and the reactant preheater, respec - tively. Similarly, the process temperatures decline (see Figure 2 ). The total heat loss from the conventional reformer system is approximately equal to the enthalpy of the natu - ral gas input, which serves as the fuel. Consequently, the enthalpy of the produced hydrogen, accounting for 51.2% of the total enthalpy input, is lower than that of the natural gas input as a raw material, representing 59.7% of the total enthalpy input.5 Results and discussion In this bespoke case, the estimated feeding rates to the SMR reactor are: The flue gas output from the reformer amounts to 540,000 t/h, with a heat content of approximately 650°C and 214 MWth per hour. The assessment of the annual heat loss in the flue gas reveals a loss of 45%, as illustrated in Figure 2. This diagram presents the substantial heat loss • Steam flow measured at 1,300 t/h. • Syngas mass flow rate at 4,000 t/h.

Flue gas

Steam

Synthesegas

Figure 1 Simplified process flow diagram of an SMR with a heat-loss recovery system

PTQ Q2 2026