Equipment corrosion control method in producing urea by using CO2 stripping method

Abstract

The invention discloses an equipment corrosion control method in producing urea by using a CO2 stripping method. According to the corrosion control method, the steam pressure of a stripping tower is controlled at 1.8-2.2Mpa; the effluent temperature of the stripping tower is controlled at 165-174 DEG C; the liquid level height of the stripping tower is 25-30% of the total height of the stripping tower; and the production load of the stripping tower is controlled at 70-110%. By using the equipment corrosion control method in producing urea by using the CO2 stripping method, the stripping tower is controlled, so that equipment is effectively protected, the corrosion is reduced, the consumption is reduced, the hidden troubles in safety production are eliminated, the long-period stable production is realized, and a higher economic benefit is brought for enterprises.

Description

technical field [0001] The present invention relates to CO 2 The technical field of stripping urea production, specifically relates to a CO 2 Anticorrosion method for equipment in steam stripping urea production. Background technique [0002] The urea production system mainly contains the following media: liquid ammonia, CO 2 , ammonia water, urea solution, water, steam, ammonium carbamate solution, and urea methylammonium solution, etc., because some of them are relatively corrosive, they will cause certain corrosion to urea production equipment, pipelines, pipe fittings, etc., which will affect the equipment long service life, causing huge economic losses, and may even endanger personal safety. Therefore, the corrosion problem of urea system equipment must be highly valued, and the corrosion problem should be the top priority to ensure the safe, stable and long-term operation of the urea system. [0003] CO 2 The corrosion of equipment in the production of urea by ste...

AI Technical Summary

Problems solved by technology

[0003] CO 2 The corrosion of equipment in the production of urea by steam stripping is generally caused by the following reasons. One is improper material selection, that is, the material selection of production equipment or equipment internals, pipes, pipe fittings, etc. cannot meet the requirements for use; Lack of strictness will lead to corrosion of the equipment during operation; third, frequent start-up and shutdown or too long time for sealing the tower; fourth, poor insulation of urea equipment, pipelines, and pipe fittings, and poor insulation will cause NH 3 , CO 2 、H 2 O mixed gas condenses into anoxic urea methylammonium liquid in the equipment lining layer or pipeline and accumulates on the local surface, forming corrosion to equipment and pipelines; there is another reason, which is also a reason that is easily overlooked, which is the process index Improper control can also easily lead to CO 2 Corrosion of Equipment in the Production of Urea by Stripping