Process for the production of formaldehyde-stabilized urea

A process for the production of formaldehyde-stabilized urea comprising the steps of:

• (a) generating a synthesis gas comprising hydrogen, nitrogen, carbon monoxide, carbon dioxide and steam in a synthesis gas generation unit;
• (b) subjecting the synthesis gas to one or more stages of water-gas shift in one or more water-gas shift reactors to form a shifted gas;
• (c) cooling the shifted gas to below the dew point and recovering condensate to form a dried shifted gas;
• (d) recovering carbon dioxide from the dried shifted gas in a carbon dioxide removal unit to form a recovered carbon dioxide-containing gas stream and a carbon dioxide-depleted synthesis gas;
• wherein the carbon dioxide removal unit operates by means of absorption using a liquid absorbent and comprises an absorbent regeneration unit, wherein the process includes recovering the carbon dioxide-containing gas stream from the absorbent regeneration unit, compressing a first portion of the recovered carbon dioxide-containing gas stream to form a compressed carbon dioxide-containing gas stream and passing the compressed carbon dioxide-containing gas stream to a methanol synthesis unit and separately passing a second portion of the recovered carbon dioxide-containing gas stream to a urea production unit;
• (e) synthesizing methanol from the carbon dioxide-depleted synthesis gas and the compressed carbon dioxide-containing gas stream in the methanol synthesis unit and recovering the methanol and a methanol synthesis off-gas comprising nitrogen, hydrogen and residual carbon monoxide;
• (f) subjecting at least a portion of the recovered methanol to oxidation with air to form formaldehyde in a stabilizer production unit;
• (g) subjecting the methanol synthesis off-gas to methanation in a methanation reactor containing a methanation catalyst to form an ammonia synthesis gas;
• (h) synthesizing ammonia from the ammonia synthesis gas in an ammonia production unit and recovering the ammonia;
• (i) reacting a portion of the ammonia and the second portion of the recovered carbon dioxide stream in the urea production unit to form a urea stream;
• and
• (j) stabilizing the urea by mixing the urea stream and a stabilizer prepared using the formaldehyde produced in the stabilizer production unit.