Tag: chemistry

Ammonia production technologies compared

A comparison of different Ammonia production technologies is made in a post on ‘Comparative studies of ammonia production, combining renewable hydrogen with Haber-Bosch’ by Trevor Brown on the Ammonia Industry blog.

It also features this these Sankey diagrams from an Italian research study by Fratelli et.al.


(published under CC BY 4.0)

All diagrams relate to the production of 1 kg of ammonia (NH3). The authors in their “research examined three cases for renewable hydrogen production, including biomass gasification (Case A), electrolysis of water using solar or wind power (Case B), and biogas reforming (Case C), and compared these sustainable hydrogen sources against the traditional steam methane reformation of natural gas (Case 0)”.

Blue flows represent electrical energy, red flows are heat energy, including the losses (off-heat). Green flows show chemical energy embodied in the product and the feedstock.

For the original study check Fratelli et al: A system approach in energy evaluation of different renewable energies sources integration in ammonia production plants. In: Renewable Energy, Volume 99, December 2016, Pages 472-482.

Casual Friday Sankey Post: Wykres Sankeya

Just before I kick off for a short weekend trip, here is another Sankey for you to enjoy. It is from the Polish language Wikipedia and shows production of KClO3.

This is more of a schematic flow diagram, as it doesn’t show any quantities. The blue boxes are processing steps. Two nice recycling loops in there from the crystalization step back to the electrolysis and from the other crystalization step back to the refining. ‘Szlam’ seems to be sludge. The individual Sankey arrows don’t show an arrow head, but little gray arrows indicate the flow direction from top to bottom.

The whole Sankey just looks kind of odd, because the main product flow is not aligned vertically. But then again, that’s up to the designer. After all, it is a fine sample of a process flow Sankey diagram.

Chemical Reaction Sankey

This rather simple Sankey diagram represents the idealized mass balance for making ammonium bicarbonate. The chemical reaction is H2O + NH3 + CO2 → NH4HCO3. It is taken from a Polish web page on chemical process technology.

The diagram is drawn with the freeware Sankey Helper. And it is nice to see that, while most of the Sankey diagrams are drawn with a left-to-right flow orientation, this one is top-to-bottom.

Sankey Diagrams in Periodic Table of Visualization Methods

Remember having to learn the elements of the periodic table back in chemistry class?

Visual Literacy now presents a ‘Periodic Table of Visualization Methods’ that has been published by two scientists from the University of Lugano in Switzerland.

Each elements represents a visualization method, from ‘C’ like ‘continuum’ to ‘Sd’ like ‘spray diagram’. The Sankey diagram can be found as element ‘Sa’ in the periodic table. It is colored in green for being in the ‘Information Visualization’ category. Furthermore its characteristics are ‘Overview’ and ‘convergent thinking’.

You can see the full periodic table at visual-literacy.org and hover the mouse over to see an example for each visualization method. The original article (Lengler R., Eppler M. (2007). Towards A Periodic Table of Visualization Methods for Management. In: IASTED Proceedings of the Conference on Graphics and Visualization in Engineering 2007, Clearwater, FL, USA) and the table separately are available as PDF files.