Problem No. 44: Rise in HP CO₂ stripper outlet temperature
A discussion about the high-pressure CO2 stripper and how to solve the problem of a high temperature in the bottom of the stripper.
Category: Equipment
Problem No. 43: Increased dust content of urea granules
Dust formation in the granulator can adversely affect stream time. There are several reasons for increased dust in the fluid bed granulator. No formaldehyde or less formaldehyde injection, lower bed level in the granulator, lower concentration of urea melt to the granulator, a higher pressure in atomisation (sprayer) air and a higher pressure in the urea melt header are all factors which can play a role. This article discusses increased dust level and its causes.
Problem No. 41: Leakage of a high pressure flange connection
Among the many problems that threaten the daily operation of a urea plant, fluid leakage is perhaps the most common, especially the leaking of high pressure flanges in the urea synthesis section. A high-velocity jet emerging from a flange due to a failed gasket, a pinhole in an elbow, corroded threads of a level transmitter, etc., are familiar scenes that the maintenance crew encounters and must rectify.
Problem No. 40: Medium pressure absorber in Saipem urea plant
Control of the process conditions of the MP absorber is one of the key control parameters in a Saipem urea plant. CO2 carryover to the ammonia receiver is not permitted in the process as it will create corrosion problems and upset conditions in the ammonia recovery and pumping system. This round table discussion considers the problems and solutions in this process section.
Problem No. 35: Urea plant preservation
Preservation covers the method of protection and preventative maintenance carried out on equipment and systems before and after they are put into use. In power plants, fertilizer units and refineries, expensive equipment like turbines, chillers, power generators, boilers, condensers, panels etc. begin to rust and corrode when in storage or during shutdown or even when in operation due to the presence of excess moisture in the air. Proper downtime procedures are extremely important. In this discussion, preservation and its importance is discussed by urea plant experts.
Problem No. 32: Temperature drop at bottom outlet of HP stripper in a Saipem urea plant
A discussion into the possible causes of a temperature drop of the HP stripper outlet of a Saipem urea plant after start-up.
Problem No. 31: Insulation of high-pressure flanges in a urea plant.
Once a flange connection in the high pressure urea synthesis section leaks it is almost impossible to stop by re-tightening the bolts. This raises the question whether the flange connection should be insulated.
Problem No. 30: What is the best stainless steel for urea?
Ammonium carbamate is very corrosive under the synthesis conditions in a urea plant. The various process licensors have developed different solutions to assure sufficient safety and reliability levels, but what is the best material?
Problem No. 29: Stripper versus decomposer: What is the difference?
A discussion defining the role of the stripper and decomposer in a urea plant and how they differ.
Problem No. 27: How do you clean the scraper in a prilling tower?
The scraper in a prilling tower rotates above the floor of the tower and moves the prills from the bottom of the prilling tower to the conveyor belt. Under certain conditions, the scraper can get clogged and requires cleaning, but how can this be done safely?