A nitrogen circular economy starts with two facts. First, the fertiliser industry uses roughly 200 million tonnes of nitrogen every year. Almost all of it comes from atmospheric nitrogen, fixed with enormous quantities of fossil energy. Second, waste streams discharge reactive nitrogen to rivers, groundwater and the air. OTAR® sits at the intersection of these two facts.
Businesses already apply the circular economy to materials and plastics. Its application to nitrogen is less familiar, but arguably more consequential. Nitrogen is one of the planet’s most critical and most wasted resources. This article explains how it works in practice and why it matters for Australia.
The Nitrogen Problem at Scale
The Haber-Bosch process fixes atmospheric nitrogen into reactive ammonia for fertiliser production. It uses roughly 1 to 2% of the world’s annual energy supply and produces around 1.4% of global CO₂ emissions. Despite this investment, much of that nitrogen never delivers its intended benefit. Instead, it leaches into waterways and causes eutrophication. It also volatilises to the atmosphere, where nitrous oxide formation adds indirect greenhouse gas emissions. In other cases, it leaves in waste streams as a compliance problem.
Why Australia Needs a Nitrogen Circular Economy
Australia depends heavily on imported nitrogen. Rabobank reported that the country imported 3.85 million tonnes of urea in 2024, which represents more than 90% of its usage. Because Australia produces so little urea locally, it stays exposed to global supply shocks.
Meanwhile, Australian piggeries, dairies, food plants and landfills already hold large pools of recoverable nitrogen on site. Recovering that nitrogen locally therefore shortens the supply chain. It also reduces exposure to imported fertiliser.
What OTAR® Does for the Nitrogen Cycle
OTAR® intercepts reactive nitrogen where it concentrates, in digestate, wastewater, leachate or industrial effluent. It then returns that nitrogen to productive use as ammonium hydroxide, anhydrous ammonia or, in Variant 3, ammonium sulphate. This closes a loop that is currently open. Rather than fixing new nitrogen from the atmosphere at Haber-Bosch energy cost, OTAR® captures nitrogen that industry has already fixed and that would otherwise escape. The environmental arithmetic is compelling: every tonne of nitrogen that OTAR® recovers displaces approximately 2 tonnes of CO₂ equivalent from avoided Haber-Bosch synthesis.
Policy and Market Tailwinds in Australia
Australian policy already points toward resource recovery. The National Waste Policy Action Plan 2019 sets an 80% average resource recovery target for all waste streams by 2030. It also targets a 50% reduction in organic waste sent to landfill. In addition, state EPAs set nutrient discharge limits, including tight limits in sensitive catchments.
OTAR® operators therefore position themselves ahead of these trends. Their investment in nitrogen recovery today is likely to become a regulatory expectation in many jurisdictions by 2030.
The Hydrogen Economy Dimension
Ammonia can carry renewable hydrogen at scale. Its high energy density and existing global transport infrastructure make it a leading candidate for zero-carbon maritime fuel and industrial energy storage. Australia’s 2024 National Hydrogen Strategy names ammonia among the industries where hydrogen can build new export industries.
OTAR® Variant 2 can produce anhydrous ammonia by concentrating recovered ammonium hydroxide. That product can feed into this emerging value chain. For facilities that invest in OTAR® today as a wastewater treatment solution, the option to supply the hydrogen economy later is a genuine strategic asset.
What This Means for Australian Operators
A nitrogen circular economy gives each Australian sector a clear commercial case. Intensive agribusiness operators can turn manure and digestate nitrogen into on-site fertiliser. Food and beverage processors can cut trade waste surcharges while creating a saleable product. Landfill asset managers can meet state EPA licence conditions while keeping leachate nitrogen out of local waterways. As a result, each sector moves from paying to dispose of nitrogen to capturing its value.
Frequently Asked Questions
How does thermal ammonia recovery contribute to the circular economy?
Thermal ammonia recovery builds a nitrogen circular economy. It captures nitrogen that waste streams would otherwise lose and returns it as fertiliser or industrial ammonia. This reduces the need to fix new nitrogen through energy-intensive Haber-Bosch synthesis. Every tonne of nitrogen that OTAR® recovers displaces about 2 tonnes of CO₂ equivalent.
Why does Australia need nitrogen recovery?
Australia imports more than 90% of its urea, so it remains exposed to global supply shocks. Recovering nitrogen from local waste streams shortens the supply chain. It also helps operators meet resource recovery targets and EPA nutrient limits.
Can recovered ammonia support the hydrogen economy?
Yes, in the longer term. OTAR® Variant 2 can concentrate recovered ammonium hydroxide into anhydrous ammonia. Ammonia is a leading hydrogen carrier, and Australia’s National Hydrogen Strategy names ammonia among its target export industries.