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Edition Tag: Nitrogen Syngas 2024-03-31

Plant Manager+

Problem No. 72: Reuse of off-spec wastewater

Every urea plant is also a water plant as the overall reaction starts with two molecules of ammonia and one molecule of carbon dioxide resulting in one molecule of urea and one molecule of water. Further water is added to the process via the steam ejectors in the evaporation section. All this water, which is contaminated with ammonia, carbon dioxide and urea plus possibly other contaminants like formaldehyde, methanol, oil, etc is collected in an ammonia water tank and then sent to a wastewater treatment section. The purpose of the wastewater treatment section is to reduce the ammonia, carbon dioxide and urea levels to acceptable levels. First the wastewater is treated in a first desorber column, where LP steam is used to strip off the ammonia and carbon dioxide, reducing the ammonia content from approx. 6-8 wt-% ammonia to approx. 1 wt-% ammonia. Nothing happens with urea in the first desorber as temperatures are too low to hydrolyse the urea back to ammonia and carbon dioxide. This takes place in the next step, in the hydrolyser, which can be quite a large counter current column operating with MP steam at approx. 23 bar (Stamicarbon design) or a horizontal deep hydrolyser operating at approx. 33 bar (Saipem design, refer to figure). Downstream of the hydrolyser there is another desorber column to strip off the remaining ammonia and carbon dioxide. Nowadays, boiler feed water quality can be realised by modern wastewater treatment. But at higher plant loads the operating margin in the wastewater treatment can become too small leading to higher ammonia and urea levels during certain operating conditions… n

Europe’s nitrogen dilemma

Nitrogen magazine, as it originally began life in It has been a tough few years for the European nitrogen industry, and between covid, gas price spikes and Russian sanctions, not all companies have weathered the storm. Now that the initial shock of the sky-high ammonia prices that the closure of the Black Sea and the cutting off of almost 40% of Europe’s gas supplies has passed, and the world gas and ammonia markets have largely adjusted to the new reality, prices are coming back down. But it seems that in its wake it may leave quite a different European nitrogen industry from the one that existed in 2019.

Price Trends

Ammonia pricing in the US Mid-West stood at $625/st f.o.b. in February, with applications to field continuing to ramp up. Prices in the US Gulf remain pegged in the low-to-mid$400s/t f.o.b. Recent production outages in the region have largely subsided, though an unexpectedly early uptick in seasonal demand from local buyers is likely to provide a degree of price support moving forward. The Tampa ammonia settlement for March has been settled by Yara and Mosaic at a $445/t c.fr rollover, largely in line with market expectations. The North American market remains detached from the considerably more oversupplied global ammonia scene.

People

Agropolychim has announced that CEO Philippe Rombaut will become chairman of Agropolychim’s board of directors, with a focus on steering the company’s strategic development. His new appointment will make way for Teodor Petsov to assume the role of head of production operations. Petsov has 22 years of production experience and a management background. In his capacity as the new production director, he will be responsible for orchestrating, overseeing, and coordinating all aspects of the company’s production activities.