Urea process with controlled excess of CO2 and/or NH3

A process for producing urea, said process comprising the steps of:

• optionally purifying a hydrocarbon feed gas to remove sulfur and/or chloride components if present,
• reforming the hydrocarbon feed gas in a reforming step with a steam/carbon molar ratio of 2-0.2, thereby obtaining a synthesis gas comprising CH4, CO, CO2, H2 and H2O,
• optionally adding H2O to the synthesis gas from the reforming step to maintain an overall steam/carbon molar ratio less than 2,
• shifting the synthesis gas in a shift section comprising one or more shift steps in series utilizing a zinc-aluminum oxide based catalyst, and operating the shift section at a steam/carbon molar ratio of less than 2.6,
• optionally cooling and/or adding H2O to the synthesis gas between the shift steps,
• optionally washing the synthesis gas leaving the shift section with water,
• removing CO2 from the synthesis gas from the shift section in a CO2 removal step to obtain a synthesis gas with less than 20 ppm CO2 and a CO2 product gas,
• removing residual H2O and/or CO2 from the synthesis gas in an absorbent step,
• removing CH4, CO, Ar and/or He from the synthesis gas in a nitrogen wash unit and adding stoichiometric nitrogen to the synthesis gas to produce NH3 synthesis gas,
• synthesizing NH3 from the NH3 synthesis gas to obtain a NH3 product,
• adding at least part of the product CO2 and at least part of the NH3 product to a urea synthesis step to make a urea product,
• wherein the amount of excess CO2 and/or NH3 is controlled by adjusting the steam/carbon molar ratio in the reforming step and/or adjusting H2O addition upstream and/or in between the shift steps and/or adjusting the inlet temperature to at least one of the one or more shift steps.