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.
We review potash mining and mineral processing methods. Advances in equipment technology and major project investments are highlighted.
Axens has developed a new titania-based catalyst named CRS 41, which has a much larger porosity than its renowned predecessor, CRS 31 catalyst. Thanks to an improved catalyst manufacturing process and a new recipe, the porosity of CRS 41 has been increased while preserving the mechanical resistance for loading, allowing customers to optimise their capex by either reducing the Claus reactor size or loading volume of TiO2 catalyst.
MECS, Inc. (MECS) has developed a new impaction-based mist eliminator called Brink® Prime Impact™ , which offers equivalent or improved efficiency at higher throughput and the same pressure drop as traditional impaction beds, resulting in the ability to debottleneck existing inter-pass absorption towers and final absorption towers in sulphuric acid plants or design new or replacement towers with smaller diameters, thus reducing investment cost.
This case study reports on the successful collaboration of two experienced partner companies to replace the problematic upper part of a co-current flow quench tower in a spent acid plant and shows the benefits of using resistant, pre-lined workshop fabricated equipment.
Steinmüller Engineering shares its experiences of applying CFD to re-design the waste heat boiler downstream of the secondary reformer to successfully achieve the desired uniform cross flow across the tube bundle.
With the aid of a rigorous kinetic model for TGU hydrogenation reactors, incorporating catalyst deactivation mechanisms, designers and operators can forecast the life expectancy of reactor catalyst beds.
In this case study Johannes Derfler of AGRU Kunststofftechnik reports on how a new condenser design, engineered by OMV and INWA AG using PFA sheets from AGRU, was implemented at OMV refinery in Austria to address maintenance problems due to corrosion of the wet sulphuric acid (WSA) condensers and the follow-up units. As a result of the renovation, maintenance costs have been cut in half, while both maintenance intervals and overall operational safety has increased.
A new burner design for the combustion of natural gas with either combustion air or pure oxygen as the oxidiser has been developed by CS Combustion Solutions. The new Oxijet® -Burner has been designed to perform both start-up and main operation functions with one burner. The key objectives, challenges, and burner design considerations are discussed.
The possible failure of refractory in a Claus unit is a concern to both licensors and operators of Claus units. Bob Poteet of WIKA discusses a novel and easy way to monitor the shell temperature of the Claus thermal reactor using proven technology and highlights the benefits a purge-less thermocouple system for high temperature measurement.