OTAR® Variant 2 absorbs stripped ammonia into water instead of acid. As a result, it produces ammonium hydroxide eligible for OMRI listing (or equivalent Australian organic input certification) — a premium certification that commands higher market value and serves a rapidly growing global market.
Most ammonia recovery technologies that go beyond thermal destruction use acid absorption to produce ammonium sulphate. OTAR® Variant 2 does not. That single design decision opens a product category that acid-route systems simply cannot access.
Why Conventional Systems Use Acid and the Consequences
Most commercial ammonia recovery installations absorb the stripped gas into sulphuric acid to produce ammonium sulphate. However, this approach requires a continuous supply of concentrated sulphuric acid. It’s a hazardous, corrosive chemical. Consequently, it demands secondary containment, WHS (Work Health and Safety) hazardous chemical compliance and careful logistics. It generates a salt-bearing product stream and permanently converts the recovered ammonia into a sulphate form. Critically, this salt-based product is not eligible for OMRI certification, locking out the premium organic agriculture market.
What OTAR Variant 2 Does Instead
OTAR® Variant 2 absorbs the ammonia gas stream into clean water, producing ammonium hydroxide (aqueous ammonia) directly. It needs no sulphuric acid and produces no ammonium sulphate salt. In addition, the process requires no acid storage, secondary containment or WHS hazardous chemicals training. The absorbed product (typically 20–25% NH₃) is clean and consistent. Where certified, it’s eligible for use in OMRI-listed (or equivalent Australian organic input certified) organic production systems. This simplicity is both an operational advantage and a commercial one.
OMRI Certification: What It Is and Why Buyers Care
The Organic Materials Review Institute (OMRI) assesses input materials against organic production standards. It works under the USDA National Organic Program and is recognised by equivalent international certification schemes. OMRI listing is a widely recognised reference standard for inputs to certified organic farming systems globally, including for Australian growers supplying export markets that require internationally recognised organic input certification. Clean water absorption qualifies ammonium hydroxide for OMRI assessment. By contrast, acid absorption disqualifies ammonium sulphate, since organic standards prohibit sulphuric acid as an input. For recovered ammonium hydroxide, this unlocks a premium-priced, growing market segment.
Beyond Agriculture: Multiple Offtake Routes
OTAR® Variant 2’s ammonium hydroxide product isn’t limited to agriculture. Established industrial markets include:
- pH control and chemical manufacturing, where ammonium hydroxide is a widely used reagent
- Selective catalytic reduction (SCR) for NOx control in power generation and heavy industry
- Municipal wastewater treatment, where it supports nitrification
- Refrigeration and the emerging hydrogen carrier economy, once further concentrated to anhydrous ammonia
Multiple offtake routes from a single production system provide important commercial resilience for Australian operators, particularly where a local organic-market buyer isn’t immediately available.
The Operational Simplicity Benefit
Eliminating acid from the process has direct operational benefits beyond product quality. There’s no acid procurement, no specialist storage infrastructure, no secondary containment for acid, and no acid-specific WHS hazardous chemical procedures. This simplifies maintenance, improves the site safety profile and makes the system easier to operate reliably. Therefore, for facilities that previously dismissed ammonia recovery over acid-handling complexity, OTAR® Variant 2 removes that barrier entirely.
Why This Matters for Australian Agribusiness & Food Processors
For intensive agribusiness operators — poultry, piggery and dairy — OMRI-aligned ammonium hydroxide turns a wastewater compliance cost into a fertiliser input that fits directly into an organic-certified supply chain.
For industrial food & beverage processors — red meat, dairy and brewing — the same product can offset purchased ammonium hydroxide already used on-site for pH control or as a reagent, reducing input costs alongside trade waste savings. And for facilities feeding a municipal sidestream, the no-acid pathway means no additional hazardous chemical handling burden layered onto an already compliance-heavy site.
The OTAR Approach
OTAR (Organics Thermal Ammonia Recovery)
OTAR is a modular platform with over 20 years of operational experience and proven installations in Asia. For operators currently spending on biological nitrogen removal, the most commercially attractive configuration is Variant 2. Which is the water absorption that converts a treatment cost into ammonium hydroxide revenue with no acid supply chain, no salt production and no hazardous chemical handling. Where waste heat is unavailable, Variant 4’s heat recycling system achieves a coefficient of performance exceeding 15, making thermal stripping viable even from cold electricity.
