Shift section features

The shift section is designed to maximise the hydrogen output and reduce the CO level in the synthesis gas and produce additional hydrogen.

The shift section consists of a high temperature shift reactor (HTS) or a medium shift reactor (MTS).

The shift process

The CO conversion section is located downstream the tubular reformer. The process converts the carbon monoxide (CO) to carbon dioxide (CO2) and produces hydrogen.

In hydrogen plants, the medium temperature shift catalysts may replace both the high and low temperature shift catalysts in which case the MTS exit gas is sent directly to a PSA unit.

Based on fundamental research Topsoe has developed shift catalysts which counter problems such as by-product formation, especially formation of hydrocarbons in high temperature shift reactors.

Topsoe's shift catalysts 

Topsoe high temperature shift (HTS) catalyst SK-201-2 is recognised as having high activity, excellent mechanical strength, and no by-product formation at low steam to carbon ratios, thus resulting in high operational flexibility. In addition the SK-201-2 comes with a negligible content of sulphur and hexavalent chromium which makes the initial activation of the catalyst fast and smooth as neither a desulphurisation period nor a reduction procedure for reducing the hexavalent chromium is required.

Topsoe medium temperature shift (MTS) catalysts LK-811/LK-813 have specifically been developed to cover a wide range of operating conditions. The standard MTS loading scheme combines the LK-811 and LK-813 catalysts in order to achieve optimal performance of the MTS section. The catalyst system is highly resistant towards chlorine and sulphur poisoning and offers high acitivity and thermal stability within the wide temperature range.