PTQ Q2 2026 Issue

refinery combustion unit. This aligns with the zero-carbon target set out in the Paris Agreement of 2015 and the global green industry. Using this technology, heat loss can be recovered and converted into approximately 4.8 MW ₑ of electrical power through an Organic Rankine Cycle (ORC) system, operat- ing at a standard conversion efficiency of approximately 24%. Flue gas properties The total heat loss of the SMR unit’s flue gas contains oxy-

180000,0

Heat content of ue gas (MJ) Heat release rate (MJ)

160000,0

140000,0

120000,0

100000,0

80000,0

60000,0

40000,0

20000,0

0.0

100

Operting conditions rate (%)

Figure 2 Heat loss/release in megajoules (MJ) of flue gas from the SMR

experienced by SMR units under the operating conditions at the refinery. This results in increased GHG emissions, exceeding emission levels, and a significant loss of energy. The total heat loss in the flue gas can be recovered, thereby converting the classic refinery into a green refinery. Heat loss recovery from the SMR unit comes directly from the reformer (reactor system) and the flue gas system. The research depends on heat recovery from both sources of heat loss by designing specialised heat exchangers with The ratio percentage of fuel/air fed into the SMR combustion unit plays a major role in flue gas and heat loss, so simulation in this unit is very important a water system that produces steam and power from the recovered heat and reduces the energy wasted in the refinery. The integration of an energy network diagram, which includes the heating and cooling energy resources of the refinery unit, can be used to present the analysis of the heat requirements of the unit or process. Additionally, it enables the assessment of potential heat-loss recovery, which can minimise energy loss in utilities and/or processes during operational conditions. This technology can be applied to reduce natural gas consumption by about 30% in each Properties of flue gas depend on the standard of flue gas with heat-loss recovery

gen, nitrogen, water, hydrocarbons, and lost gas. In this discussion, flue gas properties depend on the purity of the combustion unit’s air input linked to the SMR reactor, as well as on the fuel input in the combustion unit, which is natural gas or LPG (see Table 1 ). According to the technical standard, the heat-loss recov- ery of the flue gas in this specific SMR process amounts to approximately 40%. However, the amount and purity of the air input to the combustion unit of the SMR process play a major role in heat-loss recovery, so the quality of the natural gas or fuel should also be considered. The research refers to actual data from an SMR at a refin- ery in the Middle East. In this case study (see Table 2 ), the proportion of oxygen is about 0.04%, and the specific heat of the flue gas is 1.1 kJ/m3∙°C. The SMR optimisation can be defined in more detail by computational fluid dynamics (CFD) technologies (analysis and measurement of the com- bustion unit for both feeds – fuel and air). In the technical standard, the ratio of natural gas to air for a combustion unit is 1:4 (methane: air). However, this per- centage is not available under actual operating conditions, as shown in Table 2. ZCT Solutions has continuously developed heat-loss recovery technologies for flue gas and/or waste gas in the zero-carbon process through various R&D projects. Furthermore, technologies have been developed to convert gas and solid waste into hydrogen and power, applicable across a wide range of industries, such as refineries, pet- rochemical plants, food and pharma industries, and power plants. The ratio percentage of fuel/air fed into the SMR com- bustion unit plays a major role in flue gas and heat loss, so simulation in this unit is very important to help increase heat-loss recovery and decrease fuel consumption. The flow rate of flue gas produced per unit of time is indica- tive of combustion system efficiency and provides valuable information for its design and operation. Referring to Tables 1 and 2, the efficiency of the SMR depends on the heat content of the feed to the SMR unit (natural gas or fuel) and also the amount of oxygen that can be fed to the unit. The SMR unit flue gas can be optimised

Specification of flue gas in SMR unit Proportion of oxygen in flue gas, % Specific heat of flue gas, kJ/(m3∙°C

0.04

1.1

Temperature of flue gas, °C Ambient temperature, °C

160

35 85

Efficiency, %

Table 1

PTQ Q2 2026