Methanol production
Methanol is commonly produced by steam reforming natural gas to produce a synthesis gas that is further converted to methanol.  The crude methanol product from the methanol synthesis reactor is concentrated and purified in a two-step distillation train. The first tower, commonly called the topping column, removes light ends. The second tower, the refining column, removes intermediate components and water.

Topping and refining columns
Trays are most commonly used in the topping and refining columns. The use of trays rather than packing is particularly favored in the mid section of the refining column where intermediate boiling higher alcohols or “fusel oils” are removed as a side draw. As the selectivity changes over the life of the reactor catalyst, so does the concentration and composition of the crude methanol. This results in a change to the optimum draw stage for the fusel oil.
FLEXITRAY® valve trays combine high capacity and excellent efficiency with a wide operating range.

A tray column has the advantage over a packed tower in that it is relatively simple to include multiple draw nozzles at different trays to allow the draw stage to be varied as necessary.  For this purpose, trays such as FLEXITRAY® valve trays with type A or caged type T valves (for maximum flexibility), or MINIVALVE® tray decks with VG-0 valves are commonly used in the main two-step distillation train.

Depending on the specific plant design, packings such as IMTP® random packingINTALOX® ULTRA random packing, and FLEXIPAC® structured packing may be used in various ancillary towers such as feed saturators, deaerators and vent scrubbers. INTALOX® ULTRA random packing

Generally there are no specific fouling problems and the mass transfer equipment used is selected according to the required capacity, efficiency, pressure drop and flexibility.

Revamps
SUPERFRAC® high performance trays are often used when revamping these towers to increase plant capacity. When revamping a refining column with SUPERFRAC® trays, some of the trays may be equipped with PLUS technology deentrainment devices to provide a further gain in useable (efficient) capacity.
The SUPERFRAC® tray is a high performance cross-flow tray that has the highest combined capacity and efficienty of all cross-flow trays tested at FRI.
FLEXIPAC® HC® structured packing

The top of the refining column may also be revamped to increase capacity and/or efficiency using FLEXIPAC® HC® structured packing.