PROCESS AND APPARATUS FOR PRODUCING HYDRAZODICARBONAMIDE BY USING UREA AS STARTING MATERIAL

摘要

PURPOSE: Provided are a process and an apparatus for producing hydrazodicarbonamide(HDCA) by using urea as a starting material, which are economical and friendly to environment. CONSTITUTION: The process for producing the hydrazodicarbonamide(HDCA) comprises the steps of: heat-decomposing the urea to obtain biuret(formula 1) and ammonia in a heat decomposition furnace; refining the obtained biuret in a recrystallization reactor; reacting the recrystallized biuret with a metal hypohalogen compound, or a halogen and a base to obtain a monohalobiuret metal salt(formula 2 or 3) in a first reactor; reacting the monohalobiuret metal salt with ammonia to synthesize the hydrazodicarbonamide(HDCA) in a second reactor; separating the obtained hydrazodicarbonamide(HDCA) from surplus ammonia in an ammonia evaporator and transferring the separated ammonia to a concentrator, wherein the concentrator concentrates the surplus ammonia and the ammonia obtained from the heat decomposition furnace and supplies to the second reactor. In the formula, M is metal and X is halogen.