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.
Section: CRUNS Plant Manager+
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. 28: How to avoid hot prills in the prill tower bottom
Hot prills can easily cause caking which leads to lump formation and consequently dust formation when these lumps are crushed. This all leads to poor product quality and customer complaints, but how can hot prills be avoided?
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?
Problem No. 26: How to find a leak in a liner
The protective loose liners in high pressure urea synthesis equipment require an accurate and reliable leak detection system in order identify in time when there is a leak in the liner, but locating a small leak is not always easy to find. Several methods are available but which works best for small leaks?
Problem No. 25: High temperature in top of HP scrubber
The function of a HP scrubber is to reduce the ammonia content in the inert stream coming from the high pressure synthesis section by washing the inert stream with the recycle carbamate and cooling it against cooling water. This discussion helped to find the root cause of problem when the temperature in the top of the HP scrubber increased unexpectedly.
Problem No. 24: Why is the minimum urea plant load 60%?
It is commonly known that any urea plant has a certain minimum plant load, typically 60% of its design capacity. But why is this so critical for urea plants?
Problem No. 23: CO₂ compressor capacity limitation
The CO2 compressor in a urea plant is often a limiting factor in the urea plant. This discussion shares experiences on how best to debottleneck this unique and interesting high-pressure rotating piece of equipment.