Stefano Cicchinelli and Carmen Perez of Stamicarbon (MAIRE) explore the latest advancements in tertiary abatement technologies, their implementation in nitric acid plants, and the implications for the fertilizer industry.
As the industry pushes towards more sustainable practices, ammonia is emerging as a promising alternative fuel for ships. Effective management of by-product NOx, NH3 and N2 O emissions from the combustion of ammonia is crucial to the success of ammonia as an alternative fuel. A new catalyst has been developed by Enercat to treat these three molecules in one bed. Jean-Rémi Stephany and Emmanuel Rohart of Enercat – Alsys Group report on this new technology which has been developed in marine ammonia combustion engine conditions.
Innovative catalyst systems from Heraeus and Łukasiewicz Research Network – New Chemical Syntheses Institute contribute to reach climate goals by reducing N2 O emissions during nitric acid production. Dr Uwe Jantsch and Jens Hesse of Heraeus Precious Metals report on the process performance results achieved for N2 O reduction in nitric acid production using FTC gauze systems and iron oxide based secondary catalysts.
In this case study, Florian Kistl of CS Combustion Solutions presents a comprehensive strategy for the capacity enhancement and optimisation of a sulphuric acid production plant that was facing several operational challenges that were hindering its efficiency and reliability. As a result of a series of targeted optimisations, including the innovative use of ultrasonic nozzles and CFD modelling, downtime and maintenance costs were reduced, and a substantial capacity increase was achieved.
This troubleshooting case study describes an incident at one of the sulphur recovery units at BPCL Kochi Refinery, India. Following a maintenance turnaround of the unit in 2022, unusually high H2 S and SO2 were observed at the outlet of the Claus section. This created an additional load on the tail gas reactor, which led to frequent plugging in the quench column and frequent outages in the tail gas unit, creating environmental and reliability issues in the unit. The activities to identify the root cause of the incident are described and the measures to solve the problem are shared.
The reliability of primary reformers is a key issue for syngas plants. In this article O. Chung, N. Goodman and C. Thomas of Quest Integrity describe the damage mechanisms and material limitations that impact the reliability of reformer outlet systems and the improvements that may be implemented.
Anton Kariagin and Stefan Gebert of Clariant discuss the benefits and commercial performance of the new low temperature shift (LTS) catalyst – ShiftMax 217 Plus. A case study demonstrates the benefits of this catalyst, providing ultra-low methanol formation resulting in increased ammonia production and/or energy savings.
Tim O’Connell and Emily Viney of Johnson Matthey introduce KATALCO™ 71-7F, the latest innovation in Johnson Matthey’s KATALCO 71 series catalysts for high-temperature shift (HTS) reactions. With its robust innovative ‘F’ shape providing lower lifetime pressure drop, JM expects KATALCO 71-7F will enable large-scale plants to increase ammonia production in the most demanding HTS applications.
Cobalt-molybdenum (CoMo) catalysts are integral components of tail gas units (TGUs), playing a vital role in reducing harmful sulphur dioxide (SO2 ) emissions arising from Claus sulphur recovery units. Effective activation of these catalysts is essential for their optimal performance. The consequence of sulphiding at low temperatures and atmospheric pressure in low temperature TGUs is to compromise effectiveness of catalyst activation. In the final part of this two-part article, Michael Huffmaster , Consultant, presents case study results using a discrete reactor model incorporating heat, mass transfer, and activation reaction kinetics to assess the impacts of these variables on in-bed temperature profile and activation effectiveness. Tailoring gas rate, composition, and temperature progression can achieve in-bed exotherms which improve CoMo catalyst activation effectiveness for low temperature tail gas units.
Catalyst development for nitric acid plants is strongly dependent on operating pressures and nitrogen loading levels. Dr Hadi Nozari of Johnson Matthey provides a review of some key catalyst design principles, emphasising the critical role of operating pressure in catalyst selection and highlighting the innovative contributions of Johnson Matthey in advancing catalyst technology for ultra-high-pressure ammonia oxidation in nitric acid plants.