Technology

Most of the ammonia plants recently designed by KBR utilize its Purifier™ process (picture), which combines low-severity reforming in the primary reformer, a liquid nitrogen (N₂) wash purifier downstream of the methanator to remove impurities and adjust the H₂:N₂ ratio, a proprietary waste-heat boiler design, a unitized chiller, and a horizontal ammonia synthesis converter.

Because the secondary reformer uses excess air, the primary reformer can be smaller than in conventional designs. The cryogenic purifier consists of an expander, condenser, feed/effluent exchanger, and rectifier column and removes impurities such as CO, CH₄, and Argon from synthesis gas while adjusting the H₂:N₂ ratio of the makeup gas in the ammonia loop.

Source: V. Pattabathula & J. Richardson, Sep 2016, Introduction to Ammonia Production, AIChHE CEP.