Why co-production plant instead of standalone plants?
50% reduction in major equipment count. 40% reduction in CAPEX. 3% reduction in OPEX. GHG emission ratio reduced to 0.875 instead of 1. Significant reduction in construction cost.
Operational Flexibility to run stand-alone as well as co-production without compromising in efficiency.
Process description:
Natural gas after purification is sent to steam methane reformer/ATR/SMR+ATR/ATR+GHR based on the plant capacity, where gas mixture (feed NG + steam) is passed through the reformer unit(s). In the reforming section, feed is converted into syngas with required stoichiometric composition (module) required for methanol synthesis and this syngas is split into two streams based on individual required capacities after removing the excess heat in the boilers. The syngas gas stream for ammonia synthesis is sent to shift reactors and the gas leaving the shift converters is sent to CO2 removal section where CO2 is removed and stripped off as process CO2. Synthesis gas leaving CO2 removal section is further ultra-purified to bring CO and CO2 levels to ppb as these components are poison to NH3 synthesis catalyst.
In the O2 blown ATR based process, stoichiometric N2 required for ammonia synthesis is added after the ultra-purification unit.
The synthesis gas (H2/N2: 3:1) is pressurized to high pressure and heated in a gas-gas heat exchanger and fed to ammonia converter loaded with Fe promoted catalyst. Ammonia is synthesized in the ammonia converter and the product gas is sub-cooled to separate the NH3 from the unconverted synthesis gas.
The syngas stream for Methanol synthesis is pressurized to required methanol loop pressure and sent to methanol reactor. Methanol formation is exothermic in nature. The product stream of methanol reactor is cooled and sent to Hp separator where methanol and unconverted syngas is separated. The unconverted syngas is mixed with the feed (make-up syngas) after increasing the pressure in a compressor. To control the build-up of inerts in the methanol synthesis loop, part of the unconverted syngas stream is purged. The raw liquid methanol is sent to distillation unit for purification to meet the quality requirements (e.g., Fuel or Grade AA).