Production of melamine

Claim 1

A CONTINUOUS PROCESS OF PRODUCING MELAMINE WHICH COMPRISES CONTINUOUSLY MIXING MOLTEN UREA AND MOLTEN MELAMINE WHICH IS AT A TEMPERATURE OF 380 TO 600*C. IN A NON-PRECIOUS METAL PRESSURE-RESISTANT VESSEL AT A SUPERATMOSPHERIC PRESSURE OF AT LEAST 1000 POUNDS PER SQUARE INCH, WHICH VESSEL IS CORRODED BY UREA AND INTERMEDIATE PRODUCTS DERIVED FROM UREA BUT IS NOT APPRECIABLY CORRODED BY MOLTEN MELAMNE AT SAID TEMPERATURE, WHILE PREVENTING APPRECIABLE VAPORIZATION AND DEAMINATION OF SAID MOLTEN MELAMINE, TO FORM A FLUID SUSPENSION CONTAINING LESS THAN 30% BY WEIGHT OF UREA AND INTERMEDIATE PRODDUCTS DERIVED FROM UREAM IN WHICH SUSPENSION SAID UREA AND INTERMEDIATE PRODUCTS ARE OUT OF CONTACT WITH THE WALLS OF SAID VESSEL, SAID MOLTEN MELAMINE BEING THE SOLE SOURCE OF HEAT FOR CONVERTING SAID UREA TO MELAMINE, MAINTAINING SAID UREA AND INTERMEDIATE PRODUCTS SUSPENDED IN SAID MOLTEN MELAMINE AND OUT OF CONTACT WITH THE WALLS OF SAID VESSEL UNTIL THEY ARE CONVERTED TO MELAMINE AND GASEOUS BY-PRODUCTS, REMOVING MOLTEN MELAMINE FROM SAID VESSEL WHILE RETAINING IN SAID VESSEL A FLUID SUSPENSION CONTAINING LESS THAN 30% BY WEIGHT OF SAID UREA AND INTERMEDIATE PRODUCTS, ISOLATING A PORTION OF THE MOLTEN MELAMINE THUS REMOVED, HEATING AT LEAST A MAJOR PORTION OF THE MOLTEN MELAMINE REMOVED FROM SAID VESSEL TO A TEMPERATURE OF FROM 380 TO 600*C. WHILE PREVENTING APPRECIABLE DEAMINATION OF SAID MOLTEN MELAMINE, RECYCLING THE MOLTEN MELAMINE THUS HEATED TO SAID VESSEL FOR ADMIXTURE WITH MOLTEN UREA ACCORDING TO THE FIRST STEP OF THE PROCESS DEFINED HEREIN AND MAINTAINING THE MOLTEN MELAMINE IN THE LIQUID STATE AT A SUPERATMOSPHERIC PRESSURE OF AT LEAST 1000 POUNDS PER SQUARE INCH WHILE PREVENTING APPRECIABLE DEAMINATION THEREOF.