Top
WATER & WASTEWATER TREATMENT
Water & Waste Treatment
Industry Overview
- The Water (WTP & ETP) Treatment sector encompasses industrial facilities and systems involved in the treatment, conditioning, purification, recycling and discharge management of raw water, process water, wastewater and industrial effluents.
- The treatment requirement varies according to the source water, required water quality, industrial process and final discharge / reuse requirement.
A typical water-treatment route can be represented as:
Depending on the required quality, the treatment train may include only selected stages.
The sector includes
- Raw-water treatment
- Potable / utility water treatment
- Process-water treatment
- Demineralized-water systems
- RO and membrane treatment
- Industrial wastewater treatment
- Effluent treatment plants
- Wastewater recycling and reuse
- Sludge handling and dewatering
- Zero Liquid Discharge (ZLD), where applicable
- Water-treatment chemical systems
- Associated pumping, storage, piping, electrical and utility systems
Water Treatment Process Architecture
Typical Water Treatment Train:
Water Treatment Process Architecture
A typical ETP route is:
The actual treatment sequence depends strongly on the characteristics of the industrial effluent.
Sludge & Residuals Management
Water and wastewater treatment also generate concentrated residual streams.
A typical sludge route is:
Typical dewatering systems include:
- Filter presses
- Centrifuges
- Screw presses
- Belt filter presses
Zero Liquid Discharge / Water Recovery
Where ZLD is required, the treatment train can extend beyond conventional ETP:
ZLD systems are particularly relevant where discharge restrictions, water scarcity or high water-reuse requirements apply.
Major Industrial Applications
The major industrial applications of the sector cover raw-water treatment, process and utility water treatment, demineralization and high-purity water, industrial effluent treatment, wastewater recycling and reuse, zero liquid discharge, sludge treatment and dewatering, and municipal / industrial utility water systems.
1. Raw Water Treatment
- Surface-water treatment
- River / reservoir water treatment
- Industrial raw-water treatment
- Clarification
- Filtration
- Disinfection
2. Process & Utility Water Treatment
- Process-water treatment
- Cooling-water make-up
- Boiler feedwater preparation
- Utility-water treatment
- Industrial process-water systems
3. Demineralization & High-Purity Water
- DM plants
- RO plants
- Ion-exchange systems
- Mixed-bed systems
- EDI systems, where applicable
- High-purity water systems
4. Industrial Effluent Treatment
- Chemical effluent
- Food and beverage wastewater
- Pharmaceutical / specialty chemical wastewater
- Steel / metal industry effluent
- Oil-contaminated wastewater
- High-TDS wastewater
- Process wastewater
5. Wastewater Recycling & Reuse
- Treated-water recovery
- RO-based recycling
- Process-water reuse
- Cooling-water reuse
- Utility-water recovery
6. Zero Liquid Discharge
- RO recovery
- Reject concentration
- Evaporation
- Crystallization
- Salt / solid recovery
7. Sludge Treatment & Dewatering
- Sludge thickening
- Sludge conditioning
- Mechanical dewatering
- Sludge handling
- Cake storage / disposal
8. Municipal / Industrial Utility Water Systems
- Utility water
- Potable-water treatment, where applicable
- Sewage / wastewater treatment interfaces
- Water storage and distribution
- Pumping systems
Major Units, Facilities, Systems & Packages
The following sections set out the major units, facilities, systems and packages of the Water (WTP & ETP) Treatment sector, covering raw-water intake and pre-treatment, clarification, filtration, RO and membrane treatment, demineralization, storage and distribution, effluent collection and treatment, sludge handling, ZLD, chemical dosing, utilities and plant expansion and maintenance.
| Ref. | Section | Groups |
|---|---|---|
| 1 | Raw Water Intake & Pre-Treatment | Intake FacilitiesScreeningPre-Treatment |
| 2 | Coagulation, Flocculation & Clarification | Chemical TreatmentFlocculationClarification |
| 3 | Filtration Systems | Conventional FiltrationSpecialized FiltrationAssociated Systems |
| 4 | Reverse Osmosis & Membrane Treatment | RO SystemsMembrane SystemsMembrane Cleaning |
| 5 | Demineralization & Polishing | Ion ExchangeHigh-Purity WaterChemical Systems |
| 6 | Treated Water Storage & Distribution | StorageDistribution |
| 7 | Effluent Collection & Equalization | CollectionEqualizationEffluent Segregation |
| 8 | Oil & Grease Removal | SystemsAssociated Equipment |
| 9 | Chemical / Physical Treatment | NeutralizationChemical PrecipitationAdvanced Treatment |
| 10 | Biological Treatment | Aerobic SystemsAerationClarificationAnaerobic Systems |
| 11 | Tertiary Treatment & Polishing | Items listed directly under this section |
| 12 | Sludge Treatment & Dewatering | Sludge ThickeningConditioningDewateringSludge Handling |
| 13 | ZLD Systems | ConcentrationThermal TreatmentCrystallizationRecovery |
| 14 | Chemical Storage & Dosing Systems | Chemical StorageDosing |
| 15 | Utility Systems | PowerCompressed AirCooling |
| 16 | Water / ETP Plant Expansion, Revamp & Maintenance | ExpansionEquipment ReplacementRevamp / UpgradeShutdown / Maintenance |
1. Raw Water Intake & Pre-Treatment
Raw water intake and pre-treatment is where water enters the plant and is prepared for treatment. The groups below cover the intake facilities, screening and pre-treatment.
Intake Facilities
- Raw-water intake
- Intake screens
- Trash racks
- Intake pumps
- Raw-water pipelines
- Intake structures
Screening
- Bar screens
- Fine screens
- Rotary screens
- Automatic screening systems
Pre-Treatment
- Coarse screening
- Grit removal, where applicable
- Pre-aeration
- Pre-chlorination, where applicable
- Chemical dosing
2. Coagulation, Flocculation & Clarification
Coagulation, flocculation and clarification remove suspended solids from the water. The groups below cover chemical treatment, flocculation and clarification.
Chemical Treatment
- Coagulant dosing
- Flocculant / polymer dosing
- pH correction
- Chemical storage
- Chemical preparation systems
Flocculation
- Flocculation tanks
- Mechanical mixers
- Agitators
- Flash mixers
Clarification
- Clarifiers
- Lamella clarifiers
- Tube settlers
- Settling tanks
- Sludge collection systems
3. Filtration Systems
Filtration systems remove remaining solids and contaminants from the water. The groups below cover conventional filtration, specialized filtration and the associated systems.
Conventional Filtration
- Pressure sand filters
- Multimedia filters
- Rapid gravity filters
- Dual-media filters
Specialized Filtration
- Activated carbon filters
- Cartridge filters
- Bag filters
- Microfiltration
- Ultrafiltration
Associated Systems
- Backwash pumps
- Backwash tanks
- Air scour systems
- Filter backwash piping
- Drainage systems
4. Reverse Osmosis & Membrane Treatment
Reverse osmosis and membrane treatment remove dissolved salts and fine particles. The groups below cover RO systems, membrane systems and membrane cleaning.
RO Systems
- RO feed pumps
- Cartridge filters
- High-pressure pumps
- RO membrane vessels
- Membrane skids
- Energy-recovery systems, where applicable
- RO permeate systems
- RO reject systems
Membrane Systems
- Ultrafiltration
- Microfiltration
- Nanofiltration
- Reverse osmosis
Membrane Cleaning
- CIP systems
- Chemical dosing
- Cleaning tanks
- Cleaning pumps
- Flushing systems
5. Demineralization & Polishing
Demineralization and polishing produce high-purity water. The groups below cover ion exchange, high-purity water and chemical systems.
Ion Exchange
- Cation exchangers
- Anion exchangers
- Mixed-bed units
- Regeneration systems
High-Purity Water
- EDI systems, where applicable
- Polishing systems
- UV systems
- Final filtration
- High-purity water storage
Chemical Systems
- Acid storage
- Alkali storage
- Regeneration systems
- Chemical dosing
- Neutralization systems
6. Treated Water Storage & Distribution
Treated water storage and distribution holds treated water and delivers it to users. The groups below cover storage and distribution.
Storage
- Raw-water tanks
- Clarified-water tanks
- Filtered-water tanks
- RO permeate tanks
- DM-water tanks
- Treated-water tanks
Distribution
- Process-water pumps
- Transfer pumps
- Distribution headers
- Water pipelines
- Utility-water networks
7. Effluent Collection & EqualizationPlants
Effluent collection and equalization gather industrial effluent and balance its flow and quality before treatment. The groups below cover collection, equalization and effluent segregation.
Collection
- Effluent collection networks
- Drainage systems
- Effluent pumping stations
- Segregation systems
Equalization
- Equalization tanks
- Equalization basins
- Mixing systems
- Aeration systems
- Transfer pumps
Effluent Segregation
- Oily wastewater
- High-TDS streams
- Acid / alkaline streams
- Chemical effluent
- Organic wastewater
- Contaminated stormwater
8. Oil & Grease Removal
Oil and grease removal separates oil from wastewater before further treatment. The groups below cover the systems and the associated equipment.
Particularly relevant to refinery, petrochemical, mechanical, food and industrial facilities.
Systems
- API separators
- Oil-water separators
- CPI separators
- DAF systems
- Skimmers
- Oil collection systems
Associated Equipment
- Scraper mechanisms
- Skimmer pumps
- Oil collection tanks
- Sludge systems
9. Chemical / Physical Treatment
Chemical / physical treatment conditions the effluent through neutralization, precipitation and advanced treatment. The groups below cover each.
Neutralization
- Acid dosing
- Alkali dosing
- pH correction
- Neutralization tanks
Chemical Precipitation
- Coagulant dosing
- Flocculant dosing
- Precipitation tanks
- Reaction tanks
- Clarifiers
Advanced Treatment
- Oxidation systems
- Ozone systems
- UV systems
- Activated carbon
- Specialized chemical treatment
10. Biological Treatment
Biological treatment uses biological processes to treat the organic load of the effluent. The groups below cover aerobic systems, aeration, clarification and anaerobic systems.
Where biodegradable organic load is significant, biological treatment may form a major part of the ETP.
Where biodegradable organic load is significant, biological treatment may form a major part of the ETP.
Aerobic Systems
- Activated sludge systems
- MBBR
- SBR
- Aeration tanks
- Biological reactors
Aeration
- Air blowers
- Diffusers
- Aeration grids
- Air distribution piping
Clarification
- Secondary clarifiers
- Return activated sludge systems
- Waste activated sludge systems
Anaerobic Systems
- Anaerobic reactors
- Biogas collection
- Biogas handling
- Gas treatment systems
11. Tertiary Treatment & Polishing
Tertiary treatment and polishing give the treated effluent its final quality. The items below are listed directly under this section.
Tertiary Treatment & Polishing
- Pressure filtration
- Multimedia filtration
- Activated carbon
- UF
- RO
- UV
- Ozone
- Final disinfection
- Final polishing systems
The objective is to achieve the required reuse, recycling or discharge quality.
12. Sludge Treatment & Dewatering
Sludge treatment and dewatering thicken, condition and dewater the sludge and handle the resulting cake. The groups below cover each stage.
Sludge Thickening
- Gravity thickeners
- Mechanical thickeners
- Sludge holding tanks
Conditioning
- Polymer dosing
- Chemical conditioning
- Sludge mixing
Dewatering
- Filter presses
- Belt filter presses
- Screw presses
- Centrifuges
Sludge Handling
- Sludge conveyors
- Sludge cake handling
- Storage
- Loading / disposal systems
13. ZLD Systems
ZLD systems concentrate, treat and crystallize the effluent so that water is recovered and solids are separated. The groups below cover concentration, thermal treatment, crystallization and recovery.
Concentration
- RO systems
- High-recovery RO
- Reject concentration
- Evaporators
Thermal Treatment
- Mechanical vapour recompression, where applicable
- Multiple-effect evaporators
- Forced-circulation evaporators
Crystallization
- Crystallizers
- Salt separation
- Solid-liquid separation
- Centrifuges
Recovery
- Condensate recovery
- Recovered-water storage
- Salt / solid handling
14. Chemical Storage & Dosing Systems
Chemical storage and dosing systems store the chemicals used across the plant and dose them to the process. The groups below cover chemical storage and dosing.
Chemical Storage
- Acid tanks
- Alkali tanks
- Coagulant tanks
- Polymer systems
- Chlorine / hypochlorite systems
- Antiscalant systems
- Cleaning chemical tanks
Dosing
- Metering pumps
- Dosing skids
- Chemical injection systems
- Mixing systems
- Chemical distribution piping
15. Utility Systems
Utility systems support the treatment plant with power, compressed air and cooling. The groups below cover each.
Power
- Transformers
- Switchgear
- MCCs
- Distribution panels
- DG sets
- UPS systems
Compressed Air
- Air compressors
- Air receivers
- Air dryers
- Instrument air systems
Cooling
- Cooling-water systems
- Chillers
- Heat exchangers
16. Water / ETP Plant Expansion, Revamp & Maintenance
This section covers work on existing plants: expansion, equipment replacement, revamp / upgrade, and shutdown / maintenance. The groups below set out the items under each.
Expansion
- Additional treatment trains
- Additional RO capacity
- New clarifiers
- Additional biological treatment
- Additional storage
- Additional pumping capacity
Equipment Replacement
- Pumps
- Blowers
- Filters
- Membrane systems
- Clarifier mechanisms
- Dosing systems
- Electrical equipment
Revamp / Upgrade
- Process optimization
- Capacity enhancement
- Membrane replacement
- Automation upgrade
- Energy-efficiency improvement
- Water-recovery enhancement
Shutdown / Maintenance
- Tank inspection
- Piping inspection
- Equipment overhaul
- Membrane maintenance
- Pump / blower maintenance
- Pressure testing
- Functional testing
- Recommissioning
Sector Wise Major Commodities / Items
The WTP & ETP sector combines fabricated water-treatment equipment, tanks, piping, pressure equipment, pumps, blowers, filtration and membrane systems, chemical dosing equipment and electrical / control equipment.
The inspectable item universe can be considered through the applicable SS17, SS18 and SS19 classifications.
SS17
Basic Metals & Fabricated Metal Products
- Raw Materials
- Process & Utility Piping
- Fabricated Structures
- Tanks & Static Equipment
- Treatment Equipment Fabrication
- Fabrication & Welding
SS18
Machinery & Equipment
- Pumps
- Blowers & Compressors
- Treatment Machinery
- Filtration Equipment
- Membrane Equipment
- Water Treatment Packages
- Valves
- Sludge Equipment
SS19
Electrical & Optical Equipment
- Power Distribution
- Electrical Machines
- Power & Backup
- Cables & Protection
- Earthing & Lightning Protection
SS17 — Basic Metals & Fabricated Metal Products
SS17 — Basic Metals & Fabricated Metal Products covers the following categories for this sector: Raw Materials, Process & Utility Piping, Fabricated Structures, Tanks & Static Equipment, Treatment Equipment Fabrication and Fabrication & Welding. The items under each category are listed below.
Raw Materials
- Plates & Sheets
- Pipes & Tubes
- Bars
- Forgings
- Castings
Process & Utility Piping
- Water Piping
- Effluent Piping
- Chemical Piping
- RO / High-Pressure Piping
- Air Piping
- Pipe Fittings
- Flanges
- Fasteners
- Gaskets
Fabricated Steel Products
- Platforms
- Walkways
- Gratings
- Equipment Supports
- Pipe Racks
- Frames
- Skid Structures
- Access Structures
Tanks & Static Equipment
- Raw-water Tanks
- Clarified-water Tanks
- Treated-water Tanks
- Chemical Storage Tanks
- Equalization Tanks
- Neutralization Tanks
- Sludge Tanks
- Pressure Vessels
- Filter Vessels
- Membrane Pressure Vessels
- Air Receivers
Treatment Equipment Fabrication
- Clarifier structures
- Filter vessels
- DAF tanks
- Reaction tanks
- Sludge tanks
- Process skids
- Fabricated treatment modules
Fabrication & Welding
- Stainless-steel fabrication
- Carbon-steel fabrication
- FRP / lined equipment, where applicable
- Welding inspection
- WPS / PQR / WPQ
- NDT
- Dimensional inspection
- Coating / lining inspection
- Pressure / leak testing
SS18 — Machinery & Equipment
SS18 — Machinery & Equipment covers the following categories for this sector: Pumps, Blowers & Compressors, Treatment Machinery, Filtration Equipment, Membrane Equipment, Water Treatment Packages, Valves and Sludge Equipment. The items under each category are listed below.
Pumps
- Raw-water Pumps
- Transfer Pumps
- Process Pumps
- High-Pressure RO Pumps
- Backwash Pumps
- Chemical Dosing Pumps
- Sludge Pumps
- Effluent Pumps
- Dewatering Pumps
Blowers & Compressors
- Aeration Blowers
- Air Compressors
- Instrument-Air Compressors
- Sludge / process blowers
- Vacuum equipment, where applicable
Treatment Machinery
- Clarifier Mechanisms
- Scrapers
- Agitators
- Mixers
- DAF Systems
- Sludge Thickeners
- Sludge Dewatering Equipment
Filtration Equipment
- Pressure Filters
- Multimedia Filters
- Sand Filters
- Activated Carbon Filters
- Cartridge Filters
- Bag Filters
- Membrane Filtration Systems
Membrane Equipment
- RO Packages
- UF Packages
- NF Packages
- MF Packages
- Membrane Skids
- Membrane Pressure Vessels
Water Treatment Packages
- DM Plants
- EDI Packages
- Chemical Dosing Packages
- Water Softening Packages
- Filtration Packages
- RO Packages
- CIP Packages
Valves
- Gate Valves
- Globe Valves
- Butterfly Valves
- Ball Valves
- Check Valves
- Control Valves
- Diaphragm Valves
- Knife Gate Valves
- Special-service valves
Sludge Equipment
- Filter Presses
- Belt Filter Presses
- Screw Presses
- Decanter Centrifuges
- Sludge Conveyors
SS19 – Electrical & Optical Equipment
SS19 — Electrical & Optical Equipment covers the following categories for this sector: Power Distribution, Electrical Machines, Power & Backup, Cables & Protection and Earthing & Lightning Protection. The items under each category are listed below.
Power Distribution
- Transformers
- Distribution Transformers
- HV / MV / LV Switchgear
- MCCs
- PCCs
- Distribution Boards
- Electrical Panels
Electrical Machines
- Pump Motors
- Blower Motors
- Agitator Motors
- Fan Motors
- High-Pressure Pump Motors
- Electrical Drives
Power & Backup
- DG Sets
- Generators
- UPS
- Battery Chargers
- Battery Systems
Cables & Protection
- HV / MV / LV Cables
- Power Cables
- Control Cables
- Circuit Breakers
- Protection Relays
- Electrical Protection Equipment
Earthing & Lightning Protection
- Earthing Equipment
- Earthing Conductors
- Lightning Protection
- Associated protection components
Industrial Inspection & assurance services supporting quality, compliance and effective project execution.
QUICK LINKS
SERVICES
RESOURCES
© 2026 CQRA. All Rights Reserved.
