Keywords: ammonia, small scale production, decentralised production.
The paper reviews the technical and economical parameters for which mini-ammonia production will become feasible. Producing ammonia at a small scale means that the ammonia produced is usually more expensive in relation to capital expenditure costs, but is more environmentally sustainable, or can have lower operating costs than ammonia produced on a large scale, if produced based on sustainable, low cost or waste energy sources. The avoidance of storage and transport costs can mean that the overall operating and capital costs will be close to, or even below, the sales prices of large scale produced ammonia once brought to remote locations. As a result a credible business case can be developed, depending on the location and source of the energy, natural gas and/or hydrogen.
The production of ammonia in decentralised small scale ammonia plants can be realised using various sources of stranded energy, such as wind or solar power, flared gasses and biogas, and should be considered as one of the most sustainable methods for production of ammonia. In such a situation, based on sustainable or low cost stranded power/gas or hydrogen, ammonia can be produced at a very low operating cost, much lower than traditionally produced ammonia.
Mini production units have a different safety regime to conventional ones, as they only contain a maximum of 3 tonnes of pure ammonia. A small safety scrubber and flare is included, and a flare for the (scrubbed) purge gas stream from the ammonia synthesis loop removes argon and helium. The mini plants are designed to operate unmanned, but are monitored by a remotely located panel operator. Mini ammonia plants based on sustainable energy and/or by-product hydrogen can be realised today returning a reasonable return on capital invested in specific parts of the world. Green ammonia produced from sustainable sources will be a product creating a new market with a premium pricing. Additionally, storage opportunities for green ammonia are developing fast because major power companies see an upcoming need for such large scale storage.
J P Vrijenhoef, Proton Ventures BV, Netherlands
16 pages, 6 figures, 2 plates, 1 table, 6 references