PTQ Q2 2023 Issue

Action/set points

Site visit and analysis of existing f ired h eater s ystem

SI no. Set points name

Action/values Increase air flow

Operating d ata a nalysis and identifying operational constraints

FD fan regulation for safe operation

to furnace

Screening of data and feeding into software

2 3 4 5 6 7

Real-time air flow set point Real-time oxygen set point Air bypass damper opening Flue gas side damper setting

111,482.65, kg/h

2.99, vol%

Analyse and implementation of recommendations jointly with client Real -t ime e fficiency calculation and software recommendations for eciency improvement

Close GAPH damper

Close stack damper by 5%

Real-time efficiency

91.58% 92.03%

Best achievable efficiency

Stalilisation of parameters and further trimming

Potential benefits

Calculation of updated r eal -t ime e fficiency

SI no. Benefit

Values 0.46%

1 2 3 4

Efficiency gain potential Projected saving in fuel Projected opex benefit Projected carbon reduction

Re-verication upon change of parameters

264.46, t/y

126.94, lakhs/yr

Figure 5 Modalities of execution

740.48, t/y

Warnings

it is not linked directly to the client DCS interface as fired heater safety is susceptible to sudden changes (see Figure 4 ). Thus, the recommendations should be evaluated and implemented manually in a more controlled manner. Modalities of execution Demo runs carried out with end users highlighted some per- tinent implementation issues. In one instance, the technical head of a refinery was worried about how the software could be integrated into their regular operation. It was explained that the tags would be mapped to the software input file, and relevant data could be directly extracted from their daily data log through the MS Excel function. In another instance, a plant supervisor was apprehensive about measuring the fuel composition once a fortnight. It was recommended that more frequent measuring of fuel sulphur would provide more optimisation opportunities. The refinery agreed and increased the lab sampling frequency to twice a week to fit the software remquirement. Learning from this valuable feedback, implementation of the software in refinery fired heaters will be carried out according to the stepwise procedure shown in Figure 5 . Success stories In a demo run for a medium-scale 9 MMt/y refinery fir - ing fuel gas predominantly, the software was utilised to optimise its CDU heater (see Table 1 ). It was able to iden- tify potential fuel savings of 264 t/y by simple operating parameter adjustments without incurring any added capital expenditure (capex). All it called for was some adjustments to the excess air. The refinery could add a healthy INR 126 lakhs/annum (US$0.15 million) to its profit margin and help the environment by reducing around 740 t/y of GHG. In another instance, the recommendation card of the soft- ware successfully identified an anomaly between its oxygen analyser reading vis-à-vis predicted value. Thus, such data reconciliation is also possible utilising the digital tool. Key takeaways The digital platform offers the following benefits to refiners in optimising their fired heater operation: • Cashing in on available opportunities without major hard- ware changes

Check oxygen analyser or air flowmeter

Table 1

• Optimising operation for current operating conditions and optimise available hardware • Ensures preventive maintenance of auxiliaries • Identifies lost opportunities and investment opportuni - ties for further benefit • Aids refineries in reducing carbon footprint and GHG emissions through better optimised operation. • Eliminates the need to depend on specialised fired heater contractors for minor optimisation exercises With EIL’s declaration to achieve net zero by 2035 and create an impact on the hydrocarbon community, the digi- tal platform bolsters EIL’s commitment to protecting the environment by helping industry cut its Scope 1 emission figures. Acknowledgement The authors would like to whole-heartedly thank the management of Engineers India Limited for the support and encouragement in develop- ing the software module.

*Note: EngRT-Htr is a mark of Engineers India Ltd.

Grandhi Srivardhan is Senior Manager in Engineers India Limited’s Research and development division. He is involved in various energy optimisation studies and development of energy-efficient processes for oil refineries and petrochemical plants. He holds a Master’s degree in chemical engineering from I.I.T. Kanpur. Email: srivardhan.g@eil.co.in Rupam Mukherjee is Senior Manager in Engineers India Limited’s Heat Transfer department. He has over 15 years of experience in design, engineering, and troubleshooting of fired heater systems. He holds a post-graduate degree in energy and environment management from I.I.T. Delhi. Email: rupam.mukherjee@eil.co.in Shilpa Singh is General Manager in Engineers India Limited’s Heat Transfer department with over 25 years of experience in this field. She leads a team of chemical engineers involved in grassroot designs, re- vamp studies, capacity, and efficiency improvement projects for fired heater systems. She holds a Bachelor’s degree in chemical engineering from I.I.T. Delhi. Email: shilpa@eil.co.in

PTQ Q2 2023