	US 12,084,406 B2
	Ferritic steel parts in urea plants
Kirk Anguah Ofei, Eindhoven (NL); and Alexander Aleida Antonius Scheerder, Roosteren (NL)
Assigned to STAMICARBON B.V., Sittard (NL)
Filed by STAMICARBON B.V., Sittard (NL)
Filed on Dec. 21, 2022, as Appl. No. 18/069,690.
Application 18/069,690 is a division of application No. 17/624,716, granted, now 11,746,084, previously published as PCT/NL2020/050438, filed on Jul. 3, 2020.
Claims priority of application No. 19184798 (EP), filed on Jul. 5, 2019.
Prior Publication US 2023/0123681 A1, Apr. 20, 2023
Int. Cl. C07C 273/04 (2006.01); B01D 1/06 (2006.01); B01D 3/34 (2006.01); B01J 19/00 (2006.01); B01J 19/02 (2006.01); B22F 7/06 (2006.01); C07C 273/16 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/26 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/48 (2006.01)

CPC C07C 273/04 (2013.01) [B01D 1/065 (2013.01); B01D 3/346 (2013.01); B01J 19/0013 (2013.01); B01J 19/02 (2013.01); C07C 273/16 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/26 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/48 (2013.01); B01J 2219/00081 (2013.01); B01J 2219/0286 (2013.01); B22F 7/064 (2013.01); B22F 2301/35 (2013.01); C21D 2211/005 (2013.01)]

8 Claims

1. A high pressure stripper for a urea plant, wherein the stripper is a shell-and-tube heat exchanger comprising tubes, a shell, and an upper tube sheet and a lower tube sheet, wherein the stripper is a falling-film type vertical shell-and-tube heat exchanger, wherein the stripper comprises an inlet for receiving urea solution further comprising carbamate in the tubes at an upper part of the tubes and wherein the stripper comprises an inlet for receiving steam in the shell space between the shell and the tubes and the two tube sheets, wherein the parts of the tubes which are in operation in contact with said urea solution comprising carbamate are made of ferritic steel.