Method of quantitatively producing ammonia from urea
Patent 6887449 Issued on May 3, 2005. Estimated Expiration Date: November 21, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Methods and apparatus for continuously, quantitatively producing gaseous ammonia from urea, including the steps of: dissolving urea in water to form concentrated aqueous urea comprising at least 77 wt. % urea; continuously feeding the concentrated aqueous urea into a reactor; continuously feeding a separate, additional supply water into the reactor to form an aqueous urea reaction mixture; heating the aqueous urea reaction mixture; and continuously withdrawing a gas phase product including ammonia from the reactor, is disclosed. Also disclosed are methods and apparatus for continuous and batchwise dissolution of urea to form aqueous urea solutions.
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