In the first generation of total-recycle processes, the recycle of nonconverted NH₃ and CO₂ was performed in two stages. The first recirculation stage was operated at medium pressure (18-25 bar), the second, at low pressure (2-5 bar). All nonconverted CO₂ was recycled as an aqueous solution and a large portion of NH₃ was recycled as pure NH₃. The detrimental effect of water on the reaction conversion in the urea synthesis, achieving a minimum CO₂ recycle was considered more important than achieving a low NH₃ recycle. All conventional processes typically operate at high NH₃: CO₂ ratios (4-5 mol/mol) to maximize CO₂ conversion per pass.
The main disadvantages of the conventional process are the relatively high synthesis pressure of approx. 200 bar and the NH₃ recycle.

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All urea plants with a recycle process are a combination of the following process sections:

• Compression of CO₂ and NH₃
• Synthesis
• One or more recycle stages
• Evaporation and waste water treatment (or crystallizaton section with waste water treatment)
• Finishing section (prills or granules)