Capacity increase in Nitric acid plant with Casale High Pressure Bleacher revamping

Capacity increase in Nitric acid plant with Casale High Pressure Bleacher revamping

Casale HP bleacher revamping scheme ensures a substantial capacity increase of dual pressure nitric acid plants. The strategy behind is to install a new air compressor that supplies the additional feedstock air at the same pressure level of the absorption section. This additional air is used to bleach the nitric acid through a new dedicated equipment: the HP bleacher.
The main air compressor is then unloaded of the secondary air and this extra air can be used to proportionally increase the NA capacity.
The revamping target is then achieved with none or limited impact on the major key equipment: the turbo compressor set. Considering that the dual pressure plant turbotrain is a 4 in 1 machine, any overhauling is high demanding and by minimizing the interventions the following distinctive advantages can be achieved:

• Minimize the shutdown period, shortening the revamping intervention schedule;
• Limit the expensive and critical activities on the Turboset;
• No compromise to operate the plant at the original capacity turndown.

The presentation highlights the major features of this revamping approach.