Abstract: The present disclosure provides a baffle for a shell-and-tube heat exchanger. The baffle comprises a flat plate with a region comprising a plurality of annular elements designed for receiving the tubes of the shell-and-tube heat exchanger, arranged in at least two rows, wherein a row is staggered with respect to an adjacent row, wherein the outer diameter of the annular element is less than 130% of the inner diameter of the annular element, and wherein each annular element is joined with all of its adjacent annular elements by a bridging structure in the plane of the plate, oriented along a line connecting the centers of two adjacent annular elements, thereby defining a plurality of openings in the plate. The present disclosure also provides a shell- and-tube heat exchanger, a method for heating a liquid composition, a method for stripping a liquid composition comprising urea, carbamate, ammonia and water, and a method for producing a solid, particulate, urea-based composition.