UK HQ Your time
Water Treatment

Metal Finishing pH

Plating bath pH control, pickling acid neutralisation, rinse water pH adjustment, and anodizing bath management for metal finishing operations.

pH Control for Plating, Pickling & Anodizing

Electroplating bath pH, pickling acid neutralisation, anodizing electrolyte control, and effluent compliance for metal finishing operations.

Electroplating Baths

Nickel, chrome, and zinc plating baths operate at tightly controlled pH. Sulphuric acid or caustic soda maintains bath chemistry; drag-out rinse water requires pH correction before treatment.

Nickel / ChromeDrag-Out

Pickling & Acid Cleaning

HCl and sulphuric acid pickling baths generate spent acid and rinse water at pH <2. Lime or caustic soda neutralisation raises pH to 6–9, precipitating dissolved metals simultaneously.

HCl / H2SO4Metal Precipitation

Anodizing & Conversion Coatings

Sulphuric acid anodizing operates at pH ~1. Chromate conversion coatings need pH 1.5–2.5. pH control in seal tanks (pH 5.5–6.5) ensures coating quality and corrosion resistance.

Sulphuric AnodizeChromate

Metal Finishing Effluent

Combined effluent from plating, pickling, and anodizing contains acids, alkalis, and dissolved metals. Two-stage neutralisation with metal precipitation at pH 8.5–9.0 is standard practice.

Metal Precip.8.5–9.0

Metal Finishing pH Requirements

ApplicationTarget pHReagentNotes
Nickel Plating3.8 – 4.5Sulphuric Acid / BoricChloride or sulphate bath
Chrome Plating1.0 – 2.0Sulphuric AcidChromic acid based
Zinc Plating4.0 – 5.5Acetic / Sulphuric AcidAlkaline or acid bath
Pickling Rinse6.0 – 9.0Lime / Caustic SodaFe precipitation at pH 8–9
Anodizing Bath1.0 – 2.0Sulphuric Acid180–200 g/L H2SO4
Final Effluent6.0 – 9.0Acid or AlkaliMetal precip. at 8.5–9

Metal Finishing pH Systems

Acid Dosing Skids

Sulphuric and hydrochloric acid dosing for plating bath control and pickling rinse neutralisation.

Discover More

Alkali Dosing Systems

Lime and caustic soda dosing for spent acid neutralisation and metal hydroxide precipitation.

Discover More

Automated pH Control

Plating bath pH automation with redundant sensors, peristaltic pumps, and alarm interlocks.

Discover More

Effluent neutralisation

Compact batch or continuous effluent pH correction with metal precipitation and sludge handling.

Discover More

Process Fundamentals

pH correction is a critical stage in wastewater and process water treatment. Incorrect pH can damage downstream biological systems, corrode pipework, violate discharge consent limits, and compromise product quality. Our dosing systems utilise flow-proportional control with automated feedback loops to maintain target pH within ±0.2 units, regardless of influent variability.

Neutralisation Kinetics

Rapid mixing and reaction kinetics ensure complete neutralisation before downstream processes.

Dose Control

Flow-paced and feedback-controlled dosing eliminates chemical wastage and overshoot.

Buffer Capacity

Systems account for influent buffer capacity to calculate precise reagent requirements.

Temperature Compensation

Automated temperature compensation ensures accurate pH measurement across seasonal variations.

Design Parameters & Sizing

Flow Range0.5 – 5,000 m³/h
pH Setpoint Range4.0 – 10.5 (adjustable)
Control Accuracy±0.2 pH units
Response Time<30 seconds to setpoint
Reagent Concentration10% – 98% (application specific)
MaterialsSS316L, PVC, PVDF, PTFE, rubber-lined steel
Control PhilosophyFlow-paced + cascade PID feedback
CommunicationModbus RTU/TCP, Ethernet/IP, OPC-UA

Compliance & Standards

ISO 9001:2015

Quality management systems ensuring consistent design, manufacture, and commissioning.

ATEX / IECEx

Explosion-proof dosing skids available for Zone 1 and Zone 2 hazardous area installations.

Environmental Permits

Systems engineered to meet local discharge consent limits including pH, metals, and COD.

Industry-Specific Considerations

Food & Beverage

Food-grade acid and alkali selection prevents taint and ensures compliance with food safety standards. Automated CIP integration available.

Pharmaceutical

Validated dosing systems with full IQ/OQ documentation. Hygienic design prevents biofilm formation in pure water loops.

Power Generation

High-purity dosing for boiler feed water and cooling tower blowdown neutralisation. Redundant pump arrangements ensure availability.

Mining & Minerals

Heavy-duty construction withstands aggressive mine water chemistry. Remote telemetry enables operation at unmanned sites.

Need pH correction for your process?

Contact Our Engineers for system design, sizing, and quotation.

See This Equipment in Practice

Illustrative scenarios showing how this equipment is configured for real-world applications.

Industries We Serve

Our expertise spans multiple industries with sector-specific water treatment solutions.