Dual-pressure Nitric Acid Production Technology

Three processes are competing for production of “Diluted Nitric Acid” with suitable concentration for using as product intermediate for feedstock of fertilizers plants production.

• The Mono Pressure Process (LP) where the low pressure at the absorption stage leads to limitation of acid concentration and more ammonia consumption for NOx abatement, 
• The Mono Pressure Process (HP) where the high pressure leads to loss of efficiency at the ammonia converter stage and more catalyst loss and high investment in comparison of LP mono pressure process, 
• The dual pressure process, which combines the advantages of the low pressure at the ammonia converter stage and high pressure at the absorption stage.

For small or middle size plants, the mono pressure plants (LP) are often chosen, the slight increasing of operation cost is compensated by a low CAPEX.

At a capacity above about 900 tpd, the dual pressure process shows advantages, in term of OPEX and CAPEX. Since its industrial developments in France in mid of the twentieth century, numerous and majority of new high capacity plants are based on this process. 

CEAMAG experts demonstrate an experience of more than 30 years in application of this process: living projects and process development (design of absorbers).