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.
Category: Equipment
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?
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.
Problem No. 21: Vibrations in the discharge line of the HP reciprocating carbamate pump
In all urea plants, high pressure pumps are used to pump the feedstock ammonia and carbon dioxide to the high pressure synthesis section and in most urea plants carbamate liquid is recycled from the recirculation section to the synthesis. Reciprocating pumps are used for these services and sometimes vibration problems occur in the discharge pipeline. This discussion considers the possible causes and solutions to problem.
Problem No. 20: Unblocking pipelines after a urea plant shutdown (continued)
A discussion on what measures can be taken to unblock pipelines and heat exchangers after a urea plant shutdown.
Problem No. 19: High pressure pumps – which is better reciprocating or centrifugal?
In every urea plant, high-pressure pumps are used to pump the feedstock ammonia and carbon dioxide to the high-pressure synthesis section and in most urea plants carbamate liquid is recycled from the recirculation section to the synthesis section. This discussion compares the advantages and disadvantages of reciprocating and centrifugal pumps based on operating experiences in the industry.
Problem No. 17: Loose liner or overlay welding?
A discussion about the differences between loose liners and overlay welding for protection of high pressure equipment in urea plants.