James Hartley
Chartered Water & Wastewater Process Engineer
CEng MIChemE · BEng (Hons) Chemical Engineering · 18 years in industrial effluent treatment
James Hartley is a chartered process engineer (CEng MIChemE) with 18 years of experience designing and commissioning industrial water and wastewater treatment plant. He has led process design on dissolved air flotation (DAF), membrane bioreactor (MBR) and moving-bed biofilm reactor (MBBR) installations for food and beverage, dairy, and municipal clients in the UK, Ireland and the Gulf.
His focus is pragmatic, standards-led design: sizing equipment against real load data, hitting discharge consents reliably, and keeping whole-life energy and chemical costs down. James writes MCBA's systems and equipment guides to translate that field experience into clear, decision-ready reference material.
Areas of expertise: Dissolved air flotation, Membrane bioreactors, MBBR, Coagulation & flocculation, Effluent compliance, Process commissioning
Articles by James Hartley
- Ballasted Flocculation Clarifier Design: Microsand and Magnetite Systems for Phosphorus and Storm Flows
- Neutralising Alkaline Construction Water with Carbon Dioxide: Chemistry, Dose, Contact Time and Permits
- Flow and Level Measurement at Wastewater Works: MCERTS, Primary Devices, Uncertainty and the Flow Settings They Protect
- Flow Distribution Chambers and Splitters: Getting an Equal Split to Parallel Treatment Units
- Inlet Screening Design for Sewage Works: Bar Spacing, Kirschmer Headloss, Screenings Quantities, Washing and Compaction
- Leak Detection and Repair: Minimum Night Flow, Acoustic Correlation and the Economics of Finding Water
- Oxygen Transfer in MBBR, IFAS and SAF Reactors: How Carrier Media Change Alpha, SOTE and Air Demand
- Moving Packaged Treatment Plant and Plant Rooms by Road: UK Dimensional Limits, Abnormal Loads and Module Sizing
- The Cost of Phosphorus Removal to Low Consents: Capex, Opex and Whole-Life Cost per Kilogram
- Pipe Condition Assessment and Burst Prediction: From Pit Depth to the Economic Renewal Date
- Recarbonation and pH Correction with CO2 After Lime Softening or Lime Dosing
- Sewage Flows and Loads: Per Capita Design Values, Non-Domestic Sources, Phosphorus Apportionment and Tankered Waste
- Heat Recovery from Sewers and Treatment Works Effluent: UK Potential, Exchanger Choice, Temperature Limits and a 1 MW Worked Example
- Septicity in Sewers and Rising Mains: Predicting Sulphide, Preventing Corrosion and Controlling Odour
- Pumping Sewage Sludge: Bingham Rheology, Pipeline Pressure Drop and Pump Selection
- Smart Water Networks: District Metering, Pressure Management and What a Calibrated Model Really Adds
- Submerged Aerated Filters and Biological Aerated Filters: Volumetric Loadings, Media Choice and the Hydraulics That Decide Performance
- Receiving Tankered Cesspool and Septic Waste at a Sewage Works: Strength, Inhibition, Reception Design and Load Limits
- Tertiary Cloth and Disc Filtration for Ultra-Low Phosphorus and Solids: Media, Loading, Coagulant and Full-Scale Results
- Tertiary Ultrafiltration of Secondary Effluent for Reuse: Screening, Inline Coagulation, Flux, Fouling, Cleaning and Cost
- Building the Hydraulic Profile of a Wastewater Treatment Works: From Flood Level at the Outfall to the Inlet Works
- Trenchless Pipe Rehabilitation: Choosing and Designing CIPP, Pipe Bursting and Sliplining
- Wastewater Temperature: Predicting It in Sewers and Tanks, and Designing for the Cold Case
- Weir Hydraulics for Flow Measurement and Flow Splitting: Sharp-Crested, V-Notch, Broad-Crested Weirs and Flumes
- Energy Benchmarking of Sewage Treatment Works: kWh per Population Equivalent, Guide and Target Values, and Where the Energy Goes
- Anammox Kinetics at Low Temperature: Modelling the Arrhenius Correction for Northern European Works
- The Microbiome of Anaerobic Ammonium Oxidation: Metagenomic Insights into Brocadia and Kuenenia
- Bioelectrochemical Systems for Wastewater Treatment: Microbial Fuel Cells and Electrolysis Cells
- The Role of Extracellular Polymeric Substances in Membrane Fouling: A Colloidal and Interfacial Science Approach
- Granular Activated Carbon: Polanyi-Dubinin Theory and Breakthrough Prediction for Micropollutant Removal
- The Kinetics of Hydroxyl Radical Reactions in Advanced Oxidation: Rate Constants, Scavenging and Reactor Design
- Japanese Wastewater Research: Five Sources Assessed for UK Engineers
- Sidestream Enhanced Biological Phosphorus Removal: Fermentation Kinetics and Volatile Fatty Acid Yield
- Hydraulic Design of Storm Tank Overflows: Weirs, Sediment and First-Flush Capture
- The Thermodynamics of Struvite Nucleation: Supersaturation Index, pH Windows and Reactor Geometry
- Tertiary Phosphorus Removal to Below 0.1 mg/L: Dosing, Flocculation and Solids Separation
- Thermal Hydrolysis Pretreatment: Hydrolysis Kinetics, Biogas Yield and Dewaterability
- Disinfection By-Products: Formation Chemistry, UK Limits and the Control Hierarchy
- Water Resources Planning and Drought Resilience: Deployable Output, Headroom and the Supply-Demand Balance
- Nutrient Neutrality and Ultra-Low Phosphorus Consents: Budgets, Chemistry and What 0.1 mg/L Really Costs
- Sewer Network Hydraulic Modelling: The Equations, the Build, and the Verification That Makes It Defensible
- Storm Overflow Spill Reduction: The Hydraulics, Storage Sizing and Control That Actually Cut Spills
- The UK Largest Water Treatment Works: Beckton, Mogden, Ashford Common and the Engineering of Scale
- UK Water Industry Challenges: Storm Overflows, Nutrients, PFAS, Carbon and How Engineers Are Responding
- Net Zero in Water Treatment: Why Process Emissions, Not Electricity, Decide the Carbon Balance
- Anammox Deammonification: The Science of PN/A Nitrogen Removal
- Chemical Dosing System Design: Pumps, Sizing and Control
- Chemical Phosphorus Removal with Metal Salts: Chemistry, Dosing and Sludge
- Air Solubility and Henry's Law: The Physics Behind DAF
- The Air-to-Solids Ratio in DAF Design, From First Principles
- DAF Bubble Dynamics and Bubble-Particle Attachment
- DAF Energy Consumption and Optimisation: Where the Power Goes
- DAF Float Sludge Handling: Skimmings, Solids and Volumes
- DAF Jar and Float Testing: The Bench-to-Pilot Protocol That Fixes Your Design
- DAF Nozzle Design: The Pressure-Release Device That Makes the Bubbles
- DAF Recycle System Design: Recycle Ratio and Pump Sizing
- DAF Saturator Design: Engineering the Air-Dissolution System
- DAF Tank Design: Hydraulics and Internal Zone Sizing
- DAF vs Sedimentation: Choosing the Right Solid-Liquid Separator
- Decanter Centrifuge Sludge Dewatering: Design, Sigma Theory and Operation
- Electrodialysis and EDR: How Ion Transport Demineralises Water
- Forward Osmosis: How the Osmotically-Driven Membrane Process Works
- High-Rate DAF Design: Hydraulic Loading, Rise Rate and Footprint
- Iron and Manganese Removal from Groundwater: The Oxidation-Filtration Approach
- The Membrane Aerated Biofilm Reactor (MABR): Bubbleless Aeration Explained
- MBBR Design: Sizing on Protected Biofilm Surface Area
- Membrane Bioreactor Design: Flux, MLSS and Aeration Energy
- Membrane Fouling and Cleaning: Diagnosis, CIP Chemistry and Protocol Design
- Metal Adsorption on Iron Oxide: Surface Complexation and Surface Precipitation
- Odour Control for Hydrogen Sulphide at Wastewater Works
- pH Neutralisation Systems: Design, Staging and Reagent Sizing
- Sludge Bulking and SVI: Diagnosing and Controlling Poor Settleability
- Sludge Conditioning Polymer: Selection, Dosing and Testing
- Activated Carbon Adsorption: Isotherms, Kinetics and Bed Design
- Aerobic Sludge Digestion and ATAD: Kinetics, Oxygen Demand and Design
- Chlorination Disinfection: Chemistry, CT and Dosing
- Constructed Wetlands for Wastewater Treatment: An Engineering Guide
- Flow Equalisation Tank Design and Sizing
- Ozonation in Water Treatment: Generation, Dose and Contactor Design
- Primary Clarifier Design: Overflow Rate, Weir Loading and Depth
- Rotating Biological Contactors: Process Theory and Design
- Trickling Filter Design: Loading Rates, Media and Removal Models
- Waste Stabilisation Ponds: Design, Loading and Pathogen Removal
- Sludge Incineration and Energy Recovery: The Combustion Balance
- Sludge Drying Fundamentals: Heat, Mass Transfer and Energy
- Struvite Phosphorus Recovery: Chemistry and Reactor Design
- Landfill Leachate Treatment: Composition, Ammonia and Treatment Trains
- Thermal Hydrolysis of Sludge: THP as Digestion Pretreatment
- Advanced Oxidation Processes for Refractory Wastewater
- Sludge Thickening Design: Solids Flux Theory and Sizing
- COD and BOD in Wastewater: Rigorous Definitions and Design Use
- UASB Reactor Design: Granulation, Hydraulics and Sizing
- Dairy Wastewater Treatment: Characterisation and Treatment Train
- Grit Removal Systems: Settling Physics, Sizing and Selection
- Aeration and Oxygen Transfer: The Engineering of Gas Transfer
- Biological Nutrient Removal: The Microbiology of N and P
- Anaerobic Digestion Fundamentals: Biochemistry, Kinetics and Reactor Design
- Electrocoagulation Water Treatment: Mechanisms and Design
- Ion Exchange Water Softening: Resin Chemistry, Capacity and Column Design
- UV Disinfection System Design: Dose, Kinetics and Reactor Sizing
- Media Filtration Design: Mechanisms, Head Loss and Backwash
- Nanofiltration Water Treatment: How the Membrane Selects Ions
- Coagulation and Flocculation: Colloid Science to Design
- Lamella Clarifier Design: Settling Theory and Sizing
- Sequencing Batch Reactor Design: Cycles, Volume and SRT
- Activated Sludge Process Design: A Kinetic Approach
- Ultrafiltration Membrane System Design: Flux, TMP and Sizing
- Reverse Osmosis System Design: A Rigorous Engineering Guide
- Industrial Wastewater Treatment: Processes & Selection
- Rotary Drum Screens: Operation, Selection and Sizing
- Screw Press vs Belt Press: Sludge Dewatering Compared
- What Is a DAF System? How Dissolved Air Flotation Works
- Brewery Wastewater Treatment: Process & Design
- MBR vs MBBR: Which Wastewater System Is Best?
- Oil and Grease Separators: Types, Sizing and Selection
- Sludge Dewatering Equipment: Types and How to Select
- How to Size a DAF System: A Step-by-Step Engineering Guide