Steam condensation

ammonium carbamate crystallization and other problems occurred during transportation of urea hydrolysis production.Thus

effects of the urea liquid mass fraction and reactor pressure on such parameters such as the compositions of the production gas

the steam condensation temperature and the ammonium carbamate crystallization temperature were investigated.The results show that

the steam condensation temperature and the ammonium carbamate crystallization temperature depended on the urea liquid mass fraction and reactor pressure.When the operation pressure was 0.7MPa and the feed mass fraction was 50%

the steam condensation temperature of the production gas was 133℃and the crystallization temperature of the ammonium carbamate was 85 ℃.Moreover

it is suggested that during the thermal insulation pipeline design

the hard or semi-hard circular thermal insulation material should be selected

and the insulation layer thickness be calculated according to the allowance maximum heat disspation rate(104 W/m2).