OTAR® Thermal Ammonia Wastewater Treatment
OTAR® is Organics’ modular platform for removing ammonia from high-strength wastewater and leachate. Depending on project requirements, ammonia can be destroyed or recovered as a useful nitrogen product.
Designed for industrial and commercial applications in Indonesia, OTAR® can be integrated with existing wastewater treatment, anaerobic digestion and energy systems
Key Facts
- Proven since 1998
- Up to 5,000 m³/day flowrate
- 10:1 ammonia reduction
- No chemicals required
- ISO 9001 & ISO 14001 certified, CE marked
Primary Applications
- POME and agro-industry wastewater
- livestock and poultry wastewater
- digestate and centrate
- landfill leachate
- food processing wastewater
- other high-ammonia industrial streams.
INDUSTRIAL NITROGEN RECOVERY
What Is OTAR® Ammonia Recovery Technology?
OTAR® (Organics Thermal Ammonia Recovery) is a modular, thermally-driven ammonia stripping and recovery system. It uses waste heat — or an integrated heat-recycling loop where no waste heat exists — to shift the ammonia equilibrium in wastewater or leachate, physically strip ammonia gas out of solution, and capture it as ammonium hydroxide, ammonium sulphate fertiliser, or safely destroy it thermally. Unlike biological nitrogen removal, OTAR® is a physical process, not a living microbial culture, making it more predictable and resistant to shock loads.
Thermal Stripping & Recovery · Modular 5-Configuration Platform · Circular Economy Product Output · EPC Delivery, Not Just Equipment
Wastewater Treatment at a Glance
- System Performance: 95–98.5% NH3 removal
- Feedstock Limits: 500 mg/L – 10,000 mg/L NH4-N
- Resource Recovery: up to 25% NH4OH, or ammonium sulphate liquid/crystal fertiliser
- Energy Profile: 90–95°C low-pressure steam or hot water; 0.15–0.25 kWh electrical per m³ treated
HOW IT WORKS
How Ammonia Stripping & Recovery Works
1. Influent Intake
Ammonia-laden leachate, digestate or trade waste enters the system already carrying ionised ammonium (NH4+) in solution.
2. Equilibrium Shift
Waste heat (or heat-recycling electricity) raises temperature and/or pH, shifting the chemical equilibrium toward free ammonia gas (NH3).
3. Stripping Column
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
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.
OTAR INDUSTRY APPLICATIONS
Five OTAR® Variants
| Variant | Configuration | Primary Outcome |
|---|---|---|
| OTAR® Variant 1 | Waste heat + thermal stripping | Ammonia destruction |
| OTAR® Variant 2 | Waste heat + water absorption | Ammonium hydroxide / ammonia recovery |
| OTAR® Variant 3 | Waste heat + acid absorption | Ammonium sulphate / ammonium salt recovery |
| OTAR-electric® Variant 4 | Electricity + internal heat recycling | Thermal ammonia treatment without external waste heat |
| OTAR® Variant 5 | pH-driven ammonia conversion and stripping | Ammonia removal using chemical-assisted operation |
Ammonia Treatment Outcomes
Ammonia removal
Reduce ammonia concentration in wastewater before discharge or further treatment.
Ammonia destruction
Convert the separated ammonia stream to a treated exhaust where destruction is the selected project objective.
Ammonium hydroxide recovery
Capture ammonia in water for potential reuse or further processing.
Ammonium sulphate recovery
Capture ammonia with an acid absorption route to produce an ammonium salt.
Concentrated ammonia
Where technically and commercially appropriate, recovered ammonia can be further processed toward a concentrated ammonia product.
Where OTAR® Fits in an Indonesian Treatment Plant
Palm oil mills (POME)
Treat ammonia-rich wastewater as part of the mill’s overall effluent treatment strategy.
Anaerobic digestion
Treat digestate or centrate where ammonia is concentrated after digestion and dewatering.
Livestock and poultry
Provide dedicated ammonia treatment for high-strength manure and process wastewater.
Landfill leachate
Reduce high ammonia loads before downstream biological treatment or discharge.
Industrial wastewater
Provide a dedicated ammonia treatment stage where nitrogen is the limiting wastewater parameter.
OTAR® and Existing Wastewater Treatment
OTAR® does not have to replace the entire wastewater treatment plant. It can be installed as a dedicated ammonia treatment stage, a side-stream treatment system, or as part of an integrated wastewater process.
Install before biological treatment or after primary settling to eliminate ammonia bottlenecks.
Treat high-concentration digestate or centrate side-streams directly at the source.
Pair with SBRs or existing biological systems for strict final-discharge compliance.
Connect directly to site biogas or waste heat systems to drastically minimize operating costs.
TECHNOLOGY COMPARISON
OTAR® vs Conventional Ammonia Treatment
| Technology | Typical Cost | Chemical Use | Carbon & Compliance Impact |
|---|---|---|---|
| OTAR® (Thermal Ammonia Recovery) | ≈0.45 GBP/kg-N (≈Rp 10,850/kg-N) | Waste heat, no caustic/acid | Avoids N₂O emissions, supports compliance with ammonia limits under PP No. 22/2021 and Permen LHK No. 5/2014 |
| pH-Adjusted Thermal Stripping | ≈1.30 GBP/kg-N (≈Rp 31,300/kg-N) | Requires caustic & acid | Moderate GHG reduction, higher OPEX |
| Biological Nitrification–Denitrification (BNR) | ≈2.95 GBP/kg-N (≈Rp 71,100/kg-N) | Aeration & carbon source | Generates N₂O (~300× CO₂ warming), high energy demand |
| Anammox Biological Process | ≈2.25 GBP/kg-N (≈Rp 54,200/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. IDR figures are indicative, converted at a reference rate of ≈24,100 IDR/GBP — update to your live or standard internal rate before publishing.
PP No. 22/2021 (Peraturan Pemerintah tentang Penyelenggaraan Perlindungan dan Pengelolaan Lingkungan Hidup) sets Indonesia's national framework for wastewater discharge standards, with sector-specific ammonia and other parameter limits detailed under Permen LHK No. P.5/2014 tentang Baku Mutu Air Limbah. Confirm the exact limit that applies to your facility's classification and discharge point before citing a specific numeric threshold.
OTAR® IN OPERATION
OTAR® Proven Performance
Organics’ ammonia treatment experience spans more than two decades. The Group reports 16+ thermal ammonia stripping facilities built since 1998 and more than 100,000 hours of compliant operation.
SENT Landfill, Hong Kong
A high-strength ammonia treatment application treating approximately 2,000 m³/day of wastewater.
- Feed flow 2,000 m³/day
- Influent ammonia 4,500 mg/L NH₃-N
- Effluent ammonia <100 mg/L NH₃-N
- Ammonia removed 8.5 tonnes/day
West New Territories (WENT) Landfill, Hong Kong
A high-strength thermal ammonia treatment installation with an ammonia concentration of 6,700 mg/L NH₃-N in the incoming stream.
- Feed flow 2,300 m³/day
- Influent ammonia 6,700 mg/L NH₃-N
- Effluent ammonia <100 mg/L NH₃-N
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
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.
Free • Preliminary Estimate • No Commitment
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.
What is OTAR® ammonia recovery technology?
OTAR® (Organics Thermal Ammonia Recovery) is a modular, thermally-driven ammonia stripping and recovery system that removes 95–98.5% of ammonia (NH3-N) from high-strength wastewater and leachate, converting it into ammonium hydroxide, ammonium sulphate fertiliser, or safely destroying it thermally, rather than treating it as biological waste.
How much ammonia can OTAR® remove?
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® only for landfill leachate?
No. Applications can include industrial wastewater, POME, digestate, centrate, livestock and poultry wastewater and other high-ammonia streams.
Does OTAR® require waste heat?
The waste-heat configurations use available thermal energy. OTAR-electric® provides an option where reliable waste heat is unavailable.
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 Bali deliver OTAR® as a full EPC solution?
Yes. Organics Bali, 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