Abstract:
AMMONIA SYNTHESIS GAS IS PRODUCED FROM GASES CONTAINING HYDROGEN AND HYDROCARBONS BY SUBJECTING THE HYDROCARBONS TO PARTIAL OXIDATION WITH AIR, REMOVING THE MAIN QUANTITY OF THE HIGHER BOILING COMPONENTS, COOLING THE REMAINING GASEOUS MIXTURE TO LIQUEFY A PORTION OF THE NITROGEN THEREIN AND SCRUBBING THE REMAINING IMPURITIES FROM THE NITROGEN-HYDROGEN MIXTURE IN A RECTIFICATION COLUMN. ADDITIONAL REFLUX LIQUID IS OBTAINED BY ONE OR MORE OF THE FOLLOWING TECHNIQUES: (A) WITHDRAWING A PORTION OF THE LIQUID NITROGEN AFTER SCRUBBING FROM A MID-PORTION IN THE RECTIFICATION COLUMN SEVERAL PLATES BELOW SAID HEAD CONDENSER, EVAPORATING SAID WITHDRAWN PORTION AND PARTLY RECYCLING SAID EVAPORATED PORTION TO THE RECTIFICATON COLUMN AT APPROXIMATELY THE MID-PORTION THEREOF; (B) ADMIXING RE-EVAPORATED SCRUBBING AGENT TO THE CRUDE GAS BEFORE PARTIAL OXIDATION THEREOF; (C) ADMIXING PART OF THE RE-EVAPORATED SCRUBBING AGENT TO THE GAS TO BE SEPARATED; AND RECYCLING A PORTION OF WASTE GAS FROM AN AMMONIA SYNTHESIS CYCLE TO THE GAS TO BE SEPARATED. THERE IS ALSO PROVIDED APPARATUS FOR THE ABOVE PROCESSES.
Abstract:
A system for the transportation of liquefied gas, e.g. in a methane-carrying tankship, in which the storage space is provided with a multiplicity of upright liquefied-gas vessels in which a quantity of the liquefied gas is retained during the return trip and the upper portions of the tanks are cooled by a cooling system in addition to the cooling afforded by the retained liquefied medium.