Ammonia Recovery Systems for Australian Industry, Agribusiness & Landfill Compliance
OTAR® is a thermally-driven ammonia stripping and recovery platform that turns a wastewater compliance cost into ammonium hydroxide or ammonium sulphate fertiliser — engineered, built and commissioned by Organics Oceania as a full EPC partner, with more than 20 years of proven operating history.
Key Facts
PROBLEMS WITH WASTE WATER IN AUSTRALIA
Why Excess Ammonia Is Becoming a Costly Liability for Australian Operators
In fact, landfill sites, intensive livestock operations, and food processors across Australia are facing the same pressure. As regulations tighten, ammonia is becoming increasingly expensive to treat.
Rising Treatment Costs
High ammonia concentrations increase the cost of digestate handling, wastewater treatment, and surcharge exposure for high-strength dischargers.
✔ Increasing OPEX
✔ Greater management complexity
✔ Risk of permit violations and penalties
Tightening EPA Discharge Limits
Overall, Australian regulations are driving lower nitrogen discharge limits.
✔ ≤ 5 mg/L TN in sensitive catchments
✔ Higher compliance requirements
✔ More high-strength sidestreams
Lost Resource Value
Every kilogram of ammonia destroyed by BNR is a kilogram of nitrogen fertiliser that Australian agriculture ultimately buys back. Nitrogen recovered as ammonium hydroxide or ammonium sulfate can instead be reused on-site or sold locally.
✔ Ammonia recovery instead of destruction
✔ Greater nitrogen value recovery
✔ New revenue opportunities
INDUSTRIAL NITROGEN RECOVERY
What Is OTAR® Ammonia Recovery Technology?
OTAR® (Organics Thermal Ammonia Recovery) is a modular, thermally driven ammonia recovery system. Specifically, it uses available waste heat to shift the ammonia equilibrium in wastewater or leachate. Where waste heat is unavailable, an integrated heat-recycling loop provides the required energy. As a result, ammonia gas is stripped from the liquid and recovered as ammonium hydroxide or ammonium sulphate fertiliser. Alternatively, it can be safely destroyed through thermal oxidation. In contrast to biological nitrogen removal, OTAR® is a physical process, not a living microbial culture, making it more predictable and resistant to shock loads.
Why OTAR®?
Ammonia Recovery
In practice, OTAR® Recovers ammonia present in digestate and wastewater and converts it into a reusable product.
Ammonium Product Generation
At the same time, depending on site requirements, OTAR® produces ammonium hydroxide, ammonium sulphate, or anhydrous ammonia.
Treatment Cost Reduction
Consequently, OTAR® reduces nitrogen treatment and effluent management costs.
Circular Economy Value
In addition, it converts a waste stream into a resource, supporting circularity and sustainability goals.
Typical Operating Range
- NH₄-N concentration: 500–10,000 mg/L
- Ammonia removal: 95–98.5%
- Recovered products: Up to 25% ammonium hydroxide or ammonium sulfate fertilizer
- Heat source: 90–95°C low-pressure steam or hot water
- Electrical demand: 0.15–0.25 kWh/m³ treated
Recovering Nitrogen or Simply Eliminating It: Which Is the Best Option?
Conventional nitrogen treatment carries an ongoing cost with no return. By comparison, OTAR® converts that same expense into a recoverable fertiliser product.
⚙️ Conventional Treatment
- Ammonia is destroyed as biological waste
- Ongoing aeration, carbon dosing & sludge disposal costs
- No product is recovered
- Vulnerable to toxic shock loads and process upset
- Requires acid, alkali or salt by-product handling
- No direct economic return
🌿Recovery with OTAR®
✓ Ammonia recovered as a usable product
✓ Ammonium hydroxide or ammonium sulphate fertiliser output
✓ Approx. 0.45 GBP/kg-N vs 2.95 GBP/kg-N for BNR
✓ Physical process, resistant to shock loads
✓ Preferred configuration needs no acid, no salt waste
✓ Full EPC delivery, proven 20+ years
HOW IT WORKS
How Ammonia Stripping & Recovery Works
1. Influent Intake
First, ammonia-laden leachate, digestate or trade waste enters the system already carrying ionised ammonium (NH4+) in solution.
2. Equilibrium Shift
Next, waste heat (or heat-recycling electricity) raises temperature and/or pH, shifting the chemical equilibrium toward free ammonia gas (NH3).
3. Stripping Column
The process then distributes the liquid is distributed over structured packing while steam or hot air strips ammonia from the liquid phase into the gas phase, typically achieving 85–99% TAN removal.
4. Absorption & Recovery
Finally, the ammonia-rich gas is absorbed into water (ammonium hydroxide), reacted with sulphuric acid (ammonium sulphate), or thermally destroyed to nitrogen gas and water vapour.
FIVE CONFIGURATIONS
One Platform, Adapted to Your Site and Product Market
OTAR®’s modular design lets it prioritise product recovery or compliance. Therefore, each installation is tailored to the site’s operating conditions.
Ammonium Hydroxide Recovery | In this configuration, waste heat strips ammonia into an OMRI-eligible ammonium hydroxide product, with no acid or salt waste. Best fit: organic-market AD/biogas developers.
Ammonium Sulfate Recovery | Here, stripped ammonia reacts with sulphuric
acid to form a liquid or crystalline fertilizer, sold through ag co-ops.
Anhydrous Ammonia Recovery | Further concentration yields anhydrous ammonia for fertilizer, refrigeration, or hydrogen-carrier use. Best fit: sites with existing anhydrous storage/offtake.
Thermal Destruction (No Recovery) | Oxidises stripped ammonia to nitrogen gas and water vapour for compliance-only sites. Best fit: landfills and WWTPs without a product market.
pH-Driven Conversion | Raises pH to strip ammonia without high heat, feeding any recovery or destruction route. Best fit: sites without reliable waste heat.
VARIOUS INDUSTRY APPLICATIONS
Built for Australia’s Highest-Intent Ammonia Challenges
Landfill Leachate
Here, OTAR® reduces nitrogen discharge, supports EPA compliance, and recovers valuable ammonia products.
Piggery, Dairy & Poultry Effluent
Similarly, this system lowers nitrogen emissions while producing ammonium sulphate fertiliser or ammonium hydroxide for reuse.
Food & Beverage Trade Waste
For food and beverage plants, OTAR® cuts discharge costs, improves compliance, and adapts to variable production loads.
Industrial Wastewater
Across industrial wastewater streams, OTAR® reduces treatment costs, meets discharge limits, and converts ammonia into valuable reusable products.
CASE STUDY
OTAR® Proven Performance
In fact, Organics Group’s OTAR® platform has more than 20 years of continuous operational history. For example, two projects illustrate the range: a long-running Australian industrial installation, and one of the largest ammonia recovery deployments in the world.
Case Study: OTAR® Thermal Ammonia Recovery, Australia
- Commissioned: March 2002
- Design flow: 12.5 m³/hr
- Influent ammonia: 1,875 mg/L NH3/NH4
Outcome: Reduced ammonia to compliant discharge levels, protecting downstream biological assets and avoiding EPA penalties — now in its third decade of continuous operation, avoiding over 20 years of rising chemical costs versus chemical-dosing alternatives.
West New Territories (WENT) Landfill, Hong Kong
- Application: Landfill leachate treatment
- Influent ammonia: up to 6,700 mg/L NH4-N
- Flow: 1,000–2,300 m³/day
Outcome: Consistently reduced ammonia to <100 mg/L, stabilising downstream treatment and enabling compliance with stringent nitrogen discharge limits, across multiple expansion lines at the same site.
COST COMPARISON
OTAR® vs Conventional Nitrogen Removal
| Technology | Typical Cost | Chemical Use | Carbon & Compliance Impact |
|---|---|---|---|
| OTAR® (Thermal Ammonia Recovery) | ≈ 0.86 AUD/kg-N | Waste heat, no caustic/acid | Avoids N₂O emissions, supports EPA compliance |
| pH-Adjusted Thermal Stripping | ≈ 2.48 AUD/kg-N | Requires caustic & acid | Moderate GHG reduction, higher OPEX |
| Biological Nitrification–Denitrification (BNR) | ≈ 5.63 AUD/kg-N | Aeration & carbon source | Generates N₂O (~300× CO₂ warming), high energy demand |
| Anammox Biological Process | ≈ 4.30 AUD/kg-N | Sensitive biological process | Lower energy than BNR, still emits some N₂O |
Note: Cost benchmarking from Organics Group project data across comparable high-strength nitrogen removal installations. The cost is based on rate (1 GBP ≈ 1.91 AUD, as of late July 2026)
What Determines the Return on an OTAR® Installation?
| Factor | Impact on Return |
|---|---|
| Ammonia concentration | Higher concentration = greater recoverable value per m³ treated |
| Flow rate treated | Higher flow increases total recoverable nitrogen volume |
| Available waste heat | On-site waste heat (biogas engines, landfill gas, process heat) sharply reduces energy cost; Variant 4 heat recycling achieves a coefficient of performance exceeding 15 where none exists |
| Current treatment cost | The higher your existing BNR or chemical-dosing spend, the greater the potential saving |
| Local off-take market | Access to a local fertiliser buyer or in-house reuse increases the value of the recovered product |
💡 Every site is different
Because every site is different, our team runs a technical assessment against your specific flow, concentration and heat availability before recommending a configuration.
See What OTAR® Could Recover On Your Site
Based on the cost and performance data above, most operators want to know one thing next: what would this look like for us? Run your numbers with our team.
FREQUENTLY ASKED QUESTIONS
We answer the most common questions about ammonia recovery
Find answers to the most common questions about OTAR® technology, ammonia recovery, and its industrial applications.
How much ammonia can OTAR® remove?
Specifically, OTAR® typically achieves 95–98.5% ammonia removal, treating feedstock concentrations from 500 mg/L up to 10,000 mg/L NH4-N, and has been proven at influent concentrations as high as 6,700 mg/L NH4-N at the West New Territories landfill in Hong Kong.
Is OTAR® cheaper than biological nitrogen removal (BNR) in Australia?
Based on Organics Group’s project cost benchmarking, OTAR® thermal ammonia recovery costs approximately 0.45 GBP per kg of nitrogen treated, compared with approximately 2.95 GBP per kg-N for conventional biological nitrogen removal, largely because OTAR® uses waste heat instead of continuous aeration, external carbon dosing and biological sludge disposal.
Does OTAR® require hazardous chemicals?
The preferred configuration (water absorption) uses no acid and produces no salt waste, meaning no ongoing acid supply chain or hazardous chemical handling — a key difference from conventional acid-scrubbing ammonia removal systems.
Does Organics Oceania deliver OTAR® as a full EPC solution?
Yes. Organics Oceania, part of the Organics Group, delivers OTAR® as a full engineering, procurement and construction (EPC) solution, from feasibility assessment and detailed design through to build, commissioning and long-term operational support.
Didn’t find your answer? Ask our OTAR® specialist directly