A reactor for the synthesis of urea

A process for synthesis of urea from ammonia and carbon dioxide in a urea synthesis vertical reactor, wherein the process is carried out in a two-phase environment including a liquid phase and a gaseous phase, wherein the process includes the formation of a mixture of the liquid phase and gaseous phase flowing upwards in the reactor and withdrawing a liquid effluent from an upper region of the reactor, and the process includes passing the mixture though a plurality of baffles aligned vertically in the reactor,

• wherein each baffle comprises an array of individual tiles, each tile comprises side walls and a top face, at least one side wall has first perforations for the liquid phase and said top face has second perforations for the gaseous phase, wherein the second perforations are smaller than the first perforations, so that the liquid phase flows predominantly through the first perforations and the gas phase flows predominantly through the second perforations, and each tile performs a separation of the gas phase from the liquid phase, and the tiles of each baffle form a two-dimensional pattern over the surface of the baffle and adjacent tiles are separated by gaps.

A method for revamping a vertical urea reactor wherein the reactor includes internal separation baffles which divide the inside of the reactor into compartments, and the method includes replacing at least one baffle of the reactor with a new baffle, wherein:

• the new baffle comprises an array of individual tiles, wherein each tile comprises side walls and a top face, at least one side wall with first perforations and said top face with second perforations, wherein the second perforations are smaller than the first perforations, and the tiles are distributed over the baffle with a two-dimensional pattern and adjacent tiles are separated by gaps wherein the first perforations provide a preferential route for the liquid phase and the second perforations provide a preferential route for the vapor phase in the reactor.