Handling acidic and alkaline cleaning cycles with pH neutralisation systems for dairy processing wastewater.
Nordic dairy wastewater standards. Norwegian, Swedish, Danish and Finnish effluent limits for milk and cheese processing.
Wastewater treatment for fluid milk processing plants. Handle CIP chemical consumption, spill milk and packaging residues.
Specialised wastewater treatment for dairy wastewater standards.
Australian dairy wastewater standards including AS 1210, AS/NZS 4020 and state EPA requirements for milk processing equipment.
Cleaning-in-place (CIP) operations generate acidic and alkaline wastewater streams with pH ranging from 2-13. These extreme pH variations must be neutralised before advanced biological treatment.
Nitric and phosphoric acid cleaning cycles generate wastewater with pH as low as 2-3, requiring neutralisation.
Sodium hydroxide cleaning cycles produce wastewater with pH up to 12-13, requiring acid neutralisation.
Sequential CIP cycles can cause rapid pH swings that challenge treatment system stability.
Extreme pH can kill beneficial microorganisms in advanced biological treatment systems, causing system failure.
Automated pH adjustment systems with acid and caustic dosing neutralise CIP wastewater to the optimal range for advanced biological treatment. Flow equalization helps manage pH fluctuations.
Balancing tanks blend acidic and alkaline streams, reducing pH variation before neutralisation.
pH control systems automatically dose acid or caustic to maintain optimal pH for treatment.
Advanced control systems provide remote monitoring, data logging, and automated reporting.
CIP wastewater is collected from various process areas and directed to treatment.
Balancing tank blends acidic and alkaline streams to reduce pH variation.
Online pH probes continuously monitor wastewater pH in real-time.
Acid or caustic is automatically dosed to achieve target pH range.
Static or mechanical mixers ensure thorough chemical dispersion.
Final pH monitoring confirms neutralisation before advanced biological treatment.
Online pH monitoring with automated dosing control ensures consistent neutralisation while minimising chemical consumption. Alarms alert operators to out-of-specification conditions.
| CIP Stage | Duration (min) | pH Range | Temperature (°C) | Volume (%) |
|---|---|---|---|---|
| Pre-rinse (water) | 5-10 | 6.5-7.5 | Ambient | 15-20% |
| Caustic wash (1-2% NaOH) | 15-30 | 11.5-13.0 | 60-80 | 25-30% |
| Intermediate rinse | 5-10 | 8.0-10.0 | Ambient | 10-15% |
| Acid wash (1-1.5% acid) | 10-20 | 2.0-3.5 | 50-70 | 15-20% |
| Final rinse (water) | 5-10 | 6.5-7.5 | Ambient | 15-20% |
Raising pH of acidic wastewater
| Chemical | Strength | Cost |
|---|---|---|
| Caustic Soda (NaOH) | High | Medium |
| Soda Ash (Na2CO3) | Medium | Low |
| Lime (Ca(OH)2) | Medium | Low |
| Magnesium Hydroxide | Low | High |
Lowering pH of alkaline wastewater
| Chemical | Strength | Safety |
|---|---|---|
| Hydrochloric (HCl) | High | Medium |
| Sulphuric (H2SO4) | High | Low* |
| Nitric (HNO3) | Medium | Medium |
| Carbonic (CO2) | Low | High |
| Application | Starting pH | Target pH | Chemical | Typical Dose (mg/L) |
|---|---|---|---|---|
| Whey neutralisation | 4.6-5.2 | 6.5-7.5 | NaOH | 200-500 |
| Acid CIP neutralisation | 2.0-3.5 | 6.5-7.5 | NaOH | 500-1,500 |
| Caustic CIP neutralisation | 11.5-13.0 | 6.5-7.5 | HCl | 300-800 |
| Mixed dairy wastewater | Variable | 6.5-8.0 | NaOH/HCl | 100-300 |
Industrial-grade pH sensors with automatic temperature compensation for accurate measurement.
Precision chemical dosing pumps with variable speed control for accurate pH adjustment.
Rapid mixing tanks and inline mixers ensure uniform chemical distribution.
Full monitoring and control with data logging, alarms, and remote access capabilities.
Solutions for Dairy Wastewater
Remove fats, oils, and suspended milk solids with chemical conditioning. Achieves >95% fat removal for high-fat dairy effluents.
Dewater dairy sludge and protein residues to 18-22% dry solids. Low-energy operation with minimal operator intervention.
High-efficiency inclined plate clarifiers for milk solids settling. Saves 90% surface area versus conventional tanks.
MBBR and SBR reactors for degrading lactose and milk proteins. Handles high BOD loads from whey and dairy residues.
Equalization and buffer tanks for handling variable dairy wastewater flows with temperature and pH stabilisation.
Neutralisation and CIP recovery vessels for pH adjustment and dairy treatment processes. Sanitary stainless steel construction.
pH correction vessels for acidic whey and alkaline CIP effluent.
View Neutralisation TanksFrom caustic CIP to whey lactic-acid drop — the chemistry behind a wildly variable stream.
NaOH 1–3% w/v at 70–80°C dissolves protein and saponifies fat. Rinse water carries 0.5–3 g/L NaOH residual. Discharge spike duration: 5–20 minutes per cycle.
HNO₃ or H₃PO₄ 0.5–1.5% w/v removes mineral scale. Rinse releases dissolved Ca²⁺ (precipitated CaSO₄ / CaCO₃ downstream). Discharge spike 5–15 minutes per cycle.
Lactic-acid fermentation in storage tanks drops pH from 6.5 to 4.2 within hours. Acid whey (cottage, Greek yogurt) inherently low pH 4.3–4.6.
10–24 hour residence absorbs CIP shocks. Cross-flow weir + sloped floor + jet mixers prevent FOG layering. Composite pH typically 5.5–9.0 after equalisation.
Cascade loop: feedforward from inlet pH analyser drives coarse dose; feedback from outlet pH trims via PID. See dosing control strategy for tuning.
For dairy: lime (cheap, alkalinity-rich), NaOH (clean, no Ca²⁺), CO₂ (gentle downward trim — see CO₂ dosing). H₂SO₄ only when major pH drop needed. Compare with oil-gas pH practice.
Our experts can design a system tailored to your specific requirements.
Our expertise spans multiple industries with sector-specific water treatment solutions.