The Methanol plant consists of the following five main process steps:
1. Feedstock Desulfurization and Saturation
2. Synthesis Gas Production and Heat Recovery
3. Synthesis Gas Compression
4. Crude Methanol Production
The plant receives 10,000 lbs/hr of 400 psig natural gas. Natural gas feedstock is desulfurized, saturated with steam in the saturator, preheated and then mixed with the remainder of process steam. The mixed stream is heated and then introduced into the Methanol Reformer.
The steam/natural gas feedstock mixture reacts in the reformer and produces synthesis gas at 1150 psig and 500F. A considerable amount of waste heat is available from the synthesis gas which is used by raising the steam, preheating natural gas feedstock and boiler feedwater. Waste heat from the flue gas from the reformer is recovered by raising steam, heating natural gas and steam feedstock and preheating combustion air.
Cooled synthesis gas is compressed using a 2500HP, 2 stage Reciprocating Compressor with an electric drive and 896 ACFM capacity. The gas then passes to the synthesis loop. After synthesis and heat exchange, crude methanol is condensed and separated. A continuous loop purge is maintained to keep the inerts at a level suitable for satisfaction; methanol production. This purge is used to produce hydrogen and as a fuel source.
The crude methanol is refined in a single distillation column comprised of 93 trays with a 50# steam reboiler to obtain fuel grade methanol product.
The utilities needed for this process are: