fbpx
Print this page
Thursday, 04 March 2021 06:55

Are the days of industrial fertiliser numbered?

Written by  Mark Daniel
Researchers from two Sydney universities have found a way of making 'green' ammonia Researchers from two Sydney universities have found a way of making 'green' ammonia

OPINION: We've been encouraged to grow our own for many years, now researchers at two Sydney universities have found a way of making 'green' ammonia and say their discovery could provide a major boost to farmers and speed up a global push to renewable hydrogen fuel.

Chemical engineers at the University of New South Wales and University of Sydney say their method of making ammonia (NH3) from air, water and renewable electricity removes the need for high temperatures, high pressure and large infrastructure, currently needed to commercially produce the gas.

The new production system, demonstrated in laboratory trials, could potentially provide a solution to the problem of storing and transporting hydrogen energy.

So, is the day of reckoning coming for the world's fertiliser manufacturers? Without doubt, ammonia synthesis was one of the major achievements of the 20th century as a source of nitrogen fertiliser, allowing farmers to quadruple the output of food crops to feed a burgeoning population. On the negative front, since the early 1900s, when it was first manufactured large-scale using the Haber-Bosch process, ammonia production has been very energy intensive. Additionally, this method also produces more carbon dioxide, than any other chemical making reaction.

Dr Emma Lovell, from UNSW's School of Chemical Engineering, says, "In fact, making ammonia consumes about 2% of the world's energy and makes 1% of its CO₂ while producing millions of tonnes of ammonia in centralised locations meant large amounts of energy were needed to transport it around the world."

Lovell and her colleagues have been looking at how to produce ammonia cheaply and on a smaller scale using renewable energy.

"The way that we did it does not rely on fossil fuel resources, nor emit CO₂," Lovell said. "Once the tehchnology is available commercially, it could be used to produce ammonia directly on site and on demand. Farmers could even do this on location to make fertiliser, removing the need for storage and transport."

Convert atmospheric nitrogen (N₂) directly to ammonia using electricity has posed a significant challenge for the last decade due to the inherent stability of N₂ that makes it difficult to dissolve and dissociate.

The research teams have conducted proof-of-concept lab experiments that used plasma (a form of lightning made in a tube) to convert air into an intermediary known among chemists as NOx - either NO₂ (nitrate) or NO₃ (nitrate).

The breakthrough of the new technology is said to be the design of the high-performance plasma reactors coupled with electrochemistry, offering the ability to generate the NOx intermediary at a significant rate and high energy efficiency.

Scientia Professor Rose Amal, who is co-director of ARC Training Centre for Global Hydrogen Economy, said the team’s “green” method of ammonia production could solve the problem of storage and transport of hydrogen energy.

“Hydrogen is very light, so you need a lot of space to store it, otherwise you have to compress or liquify it,” Professor Amal said. “But liquid ammonia actually stores more hydrogen than liquid hydrogen itself. And so there has been increasing interest in the use of ammonia as a potential energy vector for a carbon-free economy.”

Amal said ammonia could potentially be made in large quantities using the new green method ready for export.

“We can use electrons from solar farms to make ammonia and then export our sunshine as ammonia rather than hydrogen. When it arrives in countries like Japan and Germany, they can either split the ammonia and convert it back into hydrogen and nitrogen, or they can use it as a fuel.”

The team now wants to commercialise their breakthrough and is seeking to form a spin-off company to take its technology from laboratory-scale into the field, while industry supporters are forecasting that by 2050, ammonia could replace fossil fuels “in almost any application”.

More like this

A significant fertiliser breakthrough?

Former ACT MP and Federated Farmers president Owen Jennings believes he's come across a new fertilising method in Australia that yields "outstanding results".

Fert use tumbles as prices spike

Fertiliser use in New Zealand over the 18 months is about 25% down from what it consistently was for the previous decade or more, says Ravensdown chief operating officer Mike Whitty.

What's next for fertiliser?

After extreme market volatility and record-high prices in recent years, global fertiliser prices are expected to settle in 2024, despite uncertainty posed by the Israel-Hamas conflict as it currently stands.

Self-spreading fert to help keep costs down

With spring fertiliser season underway, more dairy farmers are anticipated to turn to self-spreading to help keep costs down, according to Precision Farming head of sales, Aaron Wilson.

UK tightens AN fert rules

The Agricultural Industries Confederation (AIC), the UK’s agri-supply trade association representing UK fertiliser and agronomy companies, is raising concerns that farmers, growers and buying co-operatives must brace themselves for law changes that will require them to provide photo ID when purchasing ammonium nitrate (AN) fertilisers.

Featured

Sheep drench resistance costly

Analysis by Dunedin-based Techion New Zealand shows the cost of undetected drench resistance in sheep has exploded to an estimated $98 million a year.

Dairy sheep and goat turmoil

Dairy sheep and goat farmers are being told to reduce milk supply as processors face a slump in global demand for their products.

Hurry up and slow down!

OPINION: We have good friends from way back who had lived in one of our major cities for many years.

National

Govt urged to reduce ETS units

The Climate Change Commission wants the new Government to reduce NZ Emissions Trading Scheme (ETS) auction volumes as son as…

Dairy sheep, goat woes mount

Dairy sheep and goat farmers are being told to reduce milk supply as processors face a slump in global demand…

Machinery & Products

All-terrain fert spreading mode

Effluent specialists the Samson Group have developed a new double unloading system to help optimise uphill and downhill organic fertiliser…

Can-Am showcases range

Based on industry data collected by the Motor Industry Association, Can-Am is the number one side-by-side manufacturer in New Zealand.