JM PT offers a number of reactor designs and synthesis flowsheet arrangements for methanol production, allowing us to select the right technology for your methanol plant.
Tube cooled converter
The tube cooled converter is a simple reactor which uses the feed gas to the reactor to control the temperatures in the catalyst bed. Fresh feed gas enters at the bottom of the reactor and is preheated as it flows upwards through tubes in the catalyst bed. The heated feed gas leaves the top of the tubes and flows down through the catalyst bed where the reaction takes place.
The heat of reaction is removed by counter-current exchange with feed gas which results in a temperature profile that approximates to the maximum rate curve. Operated in this manner the reactor achieves good catalyst utilization.
Radial flow steam raising converter
This steam raising converter is a radial flow reactor with catalyst outside and steam inside the tubes. In the DAVY design, fresh feed gas enters at the bottom of the reactor and into a central perforated-wall distributor pipe. The gas then flows radially out through the catalyst bed. Water from a steam drum enters at the bottom of the vessel, and flows upwards through the tubes where it is partially vaporized, removing the heat generated by the reaction before returning to the steam drum.
The reaction temperature is controlled by varying the steam pressure inside tubes embedded in the catalyst bed.
Axial flow steam raising converter
The axial flow steam raising converter is a different design in which the catalyst is contained within the tubes with boiling water on the outside. As for the radial reactor, the reaction temperature is controlled by varying the steam pressure. This arrangement gives excellent cooling of the catalyst bed and allows steam to be generated at the maximum possible pressure without overheating the catalyst.
The reactor does however require thick tube sheets that limits the maximum capacity of the reactor to around 1,500 tpd and requires a large number of tubes to accommodate that catalyst. This tends to limit the use of this type of reactor to those applications where its high heat transfer performance is required, e.g., in certain coal gasification based flowsheets.