Process description Johnson Matthey s DAVY methanation system comprises a series of reaction vessels charged with our CRG catalysts.

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1 Flowsheet: Methanation Process description Johnson Matthey s DAVY methanation system comprises a series of reaction vessels charged with our CRG catalysts. The process is split between two stages: bulk and trim methanation. Bulk methanation proceeds at high temperature and facilitates most of the feed conversion, while the low-temperature trim stage reacts residual feed to maximize the final methane content of the product stream. The bulk methanation duty is typically shared between two vessels, with a recycle stream running from the output of the second reactor back to the first reactor. Using two reactors with split feed distribution reduces the required catalyst volume and reactor diameters. In addition, the recycle stream helps to control the system temperature, given the highly exothermic nature of the methanation reactions. Recycling also maximizes conversion however, using two reactors minimizes the recycle rate required to achieve this. Purified syngas feed is split between the two bulk reactors. The stream directed to the first bulk reactor mixes with the recycle gas and then enters the reaction vessel. Inside, the gases flow over the adiabatic CRG catalyst bed, where the exothermic shift and methanation reactions proceed to equilibrium. The process stream leaving the first bulk reactor mixes with the remainder of the fresh feed that bypassed the first methanation step and enters the second bulk reactor, where again the CRG-catalyzed shift and methanation reactions proceed to equilibrium. The product from the bulk methanation stage then splits between the recycle steam and the trim methanation stage. Trim methanation also takes place across two CRG catalyst reactors, which maximizes the conversion and also helps to reduce the required recycle rate at the bulk methanation stage. After leaving the final trim methanation reactor, the methanated gas is cooled to remove water, further enriching the product gas for export. Flowsheet Figure 1

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4 The majority of applications use the standard configuration of 2 bulk and 2 trim methanators, as per figures 1-5, but take note of the following alternative configurations : Alternative configurations 1 bulk, 1 trim Application: COG methanation 1 bulk, 2 trims Application: COG methanation, small SNG

5 2 bulks, 1 trim Application: SNG product with low methane 2 bulks, 3 trim Application: SNG product with low methane

6 The Johnson Matthey advantage The combination of Johnson Matthey DAVY technology design and CRG catalysts underpins our methanation technology. Long term proven process Johnson Matthey s CRG catalyst has been used in SNG plant operation for over 30 years. Johnson Matthey has many years experience in high temperature equipment design and specification. Efficient design Heat recovery maximized. Compressor power minimized. Methanation stages minimized. Both shift and methanation reactions proceed with a single, pre reduced and highly active catalyst. No additional steam is required during operation. Low equipment costs Our methanator design uses no proprietary equipment. Design flexibility Johnson Matthey will adjust process design and heat recovery to meet clientspecific requirements.

7 The information contained within this document was previously published on a former DAVY TM website. Information contained in this publication or as otherwise supplied to Users is believed to be accurate and correct at time of going to press, and is given in good faith, but it is for the User to satisfy itself of the suitability of the Product for its own particular purpose. Johnson Matthey plc (JM) gives no warranty as the fitness of the Product for any particular purpose and any implied warranty or condition (statutory or otherwise) is excluded except to the extent that exclusion is prevented by law. JM accepts no liability for loss or damage (other than that arising from death or personal injury caused by JM s negligence or by a defective Product, if proved), resulting from reliance on this information. Freedom under Patent, Copyright and Designs cannot be assumed. Johnson Matthey Davy Technologies Limited, Registered Office 5th Floor 25 Farringdon Street London EC4A 4AB Registered in England No Offices worldwide. For contact details please visit our website. DAVY is a trademark of the Johnson Matthey group of companies JM/0317/0/PT/web 2017 Johnson Matthey Group