Our robotic catalyst removal technology was used at an operating plant for the first time in the United States to remove built-up catalyst remotely, with vessel temperatures exceeding 50°C.
The challenge
Catalyst from the gas shift reactor was removed in the first instance using a dump nozzle, located at the bottom of the catalyst bed. While this allowed for the catalyst to be gravity dumped from the vessel, not all the catalyst was removed, and this remaining catalyst can be up to 40 per cent of the total vessel volume.
Workers are typically required to enter the vessel to vacuum the remaining material, while remaining aware of the built-up catalyst around the vessel walls and the associated risk of being buried. Purging of the vessel with nitrogen is required to prevent the catalyst from self-heating. If there is insufficient nitrogen, then the catalyst bed heat up and pockets of catalyst (hot spots) can reach up to 200°C. The vessel temperature needs to be lower than 40°C for human entry meaning a consequence of the hot conditions is significant time delays.
