Urea hydrolysis, analysis

Currently, the desorption-hydrolysis units used in large domestic urea plants are generally introduced together with foreign process packages, with domestic design institutes or engineering companies responsible for the preparation of the construction drawings; from an analysis of performance, their operational efficiency is not very satisfactory. It is a common problem among domestic small and medium-sized plants that they fail to meet the design specifications due to self-developed process packages. Some small and medium-sized units, as well as a few large-scale units, have designed or modified their desorption towers into packed tower types. Although this solves the problem of liquid carryover in the desorption towers, few manufacturers manage to achieve ammonia and urea levels of less than 5 ppm in the wastewater discharged from these towers. The purified water meets only the discharge standards, and does not satisfy the requirements necessary for reuse in low-pressure boilers. However, I have learned that the Institute of Chemical Engineering at Hebei University of Technology has recently introduced a fully designed process package. This institute has been working on desorption-hydrolysis systems for nearly a decade, during which it has accumulated extensive experience in research and development as well as in engineering projects. It has successfully carried out engineering design and renovation work for the desorption-hydrolysis systems of more than 20 large and medium-sized urea production facilities in China; details of these projects are available on this forum. If needed, I can provide the contact information.