Magazine: Nitrogen+Syngas

Every urea plant continuously fights again corrosion. The intermediate product ammonium carbamate is extremely corrosive under synthesis conditions. The applied materials of construction require oxygen to form a protective passive layer of chromium oxides. The ammonium carbamate solution will continuously dissolve the passive layer, therefore it is vital to continuously supply oxygen, typically in the form of air, to maintain the passive layer. During blocking-in conditions of the synthesis section it is not possible to add air and the oxygen present will be consumed as a result of the passive corrosion reactions, while at the same time the passive layer dissolves in the ammonium-carbamate solution. At a certain point, the oxygen content in the solution becomes too low to assure a passive layer. At that moment active corrosion will start with much higher corrosion rates than passive corrosion. The picture on the left side shows the passive layer (blue, brown, grey surface) and the picture on the right side shows active corrosion (a shiny silver surface). It is important to realise that once active corrosion starts it cannot be stopped, adding more oxygen at this stage, for example, will not work. Active corrosion will continue, leading to the risk that the protective layer will be severely damaged. The only way to solve this situation is to drain the synthesis section and re-passivate the surfaces.

Nitrogen-rich wastewaters remain a major issue for fertilizer and other industries. Saipem’s new electrochemical technology, SPELL, is an important step towards the overall objective of zero industrial pollution. A complete engineering review of the technology, its alignment with all international applicable standards, and optimisation has now been concluded and the technology is ready for deployment for the removal of ammonium nitrogen from industrial waters and wastewaters. Saipem discusses the key features of SPELL and reports on the first two industrial references.

Soaring natural gas prices in Europe, up to five times higher than normal, have led to numerous economic shutdowns of ammonia capacity across the continent. This has coincided with shutdowns in the US due to hurricane season, reducing availability considerably and driving up prices in the western hemisphere.

While the past couple of years have seen considerable excitement and momentum concerning the use of blue/green ammonia as a fuel, an announcement in August by Maersk, the largest shipping company in the world, has served once again as a useful reminder that ammonia is not the only candidate molecule. Maersk said on August 24th that it is ordering eight methanol powered vessels from South Korea’s Hyundai Heavy Industries at a total cost of $1.4 billion. Each giant ship will have the capacity to carry 16,000 twenty-foot [container] equivalent units (TEUs).

Market Insight courtesy of Argus Media

OCI subsidiary Fertiglobe says that it has partnered with the Abu Dhabi National Oil Company (ADNOC), to enable the sale by ADNOC of the first cargo of blue ammonia to Itochu in Japan, for use in fertilizer production. Fertiglobe, a 58% − 42% partnership between OCI and ADNOC respectively, will produce the blue ammonia at its Fertil plant at Ruwais in Abu Dhabi for delivery to ADNOC’s customers in Japan. This represent the first production milestone of a planned scale-up of blue ammonia production capabilities in Abu Dhabi, which is expected to include a low-cost debottlenecking program at Fertil. In addition, it was announced in June that Fertiglobe will join ADNOC and sovereign wealth fund ADQ as a partner in a new world-scale 1.0 million t/a blue ammonia project at Ta’Ziz in Ruwais, subject to regulatory approvals. The design contract for this project has been awarded, with a final investment decision expected in 2022 and start-up targeted for 2025. A feasibility study was also agreed in July betweenh the state-owned Japan Oil, Gas and Metals National Corp. (Jogmec), Inpex and JERA as well as ADNOC to explore the possibility of producing 1.0 million t/a of blue ammonia in Abu Dhabi and transporting it to Japan.

Former Danish Minister of Climate, Energy, and Gender Equality, Lykke Friis , has been elected to the Blue World Technologies’ board of directors. The company says that she will support its “journey towards providing a strong green alternative to combustion engines and diesel generators for industries around the world.”

The ammonium nitrate explosion in Beirut in August 2020 has once again focused minds upon the potential risks associated with the chemical.

Venkat Pattabathula, a member of the AIChE Ammonia Safety Committee, reports on the American Institute of Chemical Engineers’ Safety in Ammonia Plants and Related Facilities Symposium, held virtually on 30 August to 2 September 2021.

The fact that biuret is toxic to plants has been known for a long time – since the middle of the last century. Very sensitive (pineapple, citrus), moderately sensitive (cereals, legumes) and resistant (conifers) plant species were identified. The maximum concentration of biuret in urea for each species has been established for soil application and foliar application. Most field crops easily tolerate foliar fertilization with urea, which contains 1 wt-% biuret. Potatoes and tomatoes are more sensitive – for foliar feeding of these crops, it is advisable to use urea with an admixture of biuret of no more than 0.5 wt-%. Citrus fruits and pineapples are so sensitive that biuret in urea for foliar feeding should be no more than 0.35 wt-%.