THE SOURCE IS THE STARTING POINT
Every source has its own characteristics. Water drawn from a lake, an aquifer, a well or a spring cannot be treated using a standard configuration.
The design starts with the water data, operating conditions and intended use. On this basis, Fulcor selects and combines the stages needed to achieve the required quality, avoiding unnecessary treatments.
THE DESIGN TAKES INTO ACCOUNT
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Water origin and abstraction method
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Water analysis results and parameters to be adjusted
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Expected flow rate and consumption
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Seasonal variations
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Intended use and required quality
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Continuity of service and long-term operation
TWO ORIGINS, DIFFERENT CHARACTERISTICS
Surface water and groundwater may require very different treatment stages. The appearance of water is not enough to assess its quality: its actual characteristics are determined through data and analyses relating to the individual source.
01 - LAKE WATER
Exposed to rainfall, inputs from the surrounding catchment and natural cycles, lake water can vary significantly throughout the year. It therefore often requires treatment involving several stages.
POSSIBLE CHARACTERISTICS:
Turbidity and suspended particles
Organic substances, algae and colour
Microbial load
Odours and variable parameters
Changes associated with rainfall, temperature and the seasons
02 - GROUNDWATER, WELL WATER OR SPRING WATER
Passing through soil and rock can make water visibly clear and more stable, but can also enrich it with minerals and dissolved substances that cannot be identified by appearance alone.
POSSIBLE CHARACTERISTICS:
Hardness and mineral salts
Iron and manganese
Dissolved gases and natural odours
Specific chemical parameters
Potential microbial contamination or contamination from the surrounding environment
CLARITY ALONE DOES NOT GUARANTEE THAT WATER IS SUITABLE FOR ITS INTENDED USE.
FULCOR BY YOUR SIDE: A CLEAR APPROACH AT EVERY STAGE
FROM RAW WATER TO WATER SUITED TO ITS USE
Designing a treatment system involves more than choosing a single piece of equipment. The stages are arranged and sized so that each prepares the water for the next and contributes to the final result.
01 — SOURCE DATA
Analyses, origin, variability and abstraction conditions.
02 — TARGET WATER QUALITY
Intended use, flow rate, consumption and required continuity of service.
03 — PREFILTRATION
Removal of solids, sediment and turbidity to protect subsequent stages.
04 — TARGETED TREATMENTS
Treatment of the physical and chemical parameters identified through the water data.
05 — DISINFECTION AND CONTROL
Disinfection where necessary, measuring instruments and checks on system operation.
THE SEQUENCE OF STAGES VARIES WITH THE SOURCE AND THE TARGET WATER QUALITY.
WHICH WATER CHARACTERISTICS NEED TO BE ADDRESSED?
Every source presents different conditions. Fulcor treats lake water and groundwater for non-potable technical applications, primarily in systems where the water is circulated and subsequently returned to its source. Further technical applications can be assessed case by case, subject to a feasibility assessment.
This page also includes information on technologies and applications that are outside Fulcor’s current offering for these waters. This content is provided for information, to explain the different treatment options in relation to the source characteristics and the intended use.
Select the issue or technology you are interested in to go directly to the relevant section.
SOLIDS AND TURBIDITY
Sand, sediment, suspended particles, colloids and algae can increase water turbidity and compromise subsequent stages. For separation and mechanical filtration, Fulcor selects systems based on the nature and quantity of the solids, the flow rate and the required filtration fineness.
01 - CENTRIFUGAL SEPARATION
CYCLONE HYDROCYCLONE
The Cyclone uses centrifugal force to separate sand and heavy particles, without a replaceable filter element. It is normally installed upstream of subsequent treatment stages.
It is preferred when groundwater or abstracted water contains significant quantities of sand and heavy sediment, and downstream filters, pumps and equipment need protection.
02 - AUTOMATIC SCREEN FILTRATION
FULROM ROTOR
FULROM ROTOR filters retain suspended particles using a screen element. Automatic cleaning with suction pads takes place without interrupting the flow, reducing manual intervention and ensuring continuous operation.
It is preferred when the water contains suspended solids that are finer or lighter than sand, the load varies over time, and continuous operation and automated control are required.
Unlike the Cyclone, it also acts on particles that do not settle easily; compared with cartridge filters, it is better suited to loads that would require frequent cartridge replacement.
The Y, L and O configurations and the different filter elements allow the system to be adapted to the water quality, flow rate and required filtration fineness.
03 — FINE FILTRATION
CARTRIDGE FILTERS
Cartridge filters retain sediment and fine particles using replaceable filter elements, available in different materials and filtration ratings. Fulcor selects the filter housing and cartridge according to the water quality, flow rate and required result.
They are preferred when fine filtration with a specified rating is needed, the solids load is not excessive, or activated carbon, membranes, UV systems and other downstream equipment require protection.
Compared with the Cyclone and automatic FULROM filters, cartridge filtration is particularly suitable as a polishing stage. If the water contains large quantities of sand or suspended solids, it is normally preceded by a separation or prefiltration stage capable of handling a higher solids load.
Cartridges must be inspected and, where specified, cleaned or replaced according to the retained material and pressure drop.
WHEN FILTRATION ALONE IS NOT ENOUGH
COAGULATION, FLOCCULATION AND CLARIFICATION
In more variable surface waters, some turbidity may be caused by colloids, organic substances, algae and particles so fine that mechanical filtration alone cannot retain them effectively.
Coagulation and flocculation promote the aggregation of particles into flocs that are easier to separate. Subsequent clarification reduces the load reaching the filters.
They are preferred when lake water has high or highly variable turbidity, colour, significant quantities of algae or colloidal particles.
Reagent type and dose, contact times and the separation system are determined from analyses and, where necessary, specific treatability tests.
HARDNESS, SALTS AND DISSOLVED SUBSTANCES
Water can appear perfectly clear and still contain salts, nitrates, organic substances or minerals responsible for hardness.
Treatment is determined by the analyses and the required quality: either selective adjustment of a specific parameter or broader separation of dissolved substances.
01 - ADSORPTION
ACTIVATED CARBON AND SELECTIVE FILTER MEDIA
Activated carbon retains organic substances and compounds responsible for odours, tastes and certain types of colour by adsorption — that is, on its surface. Where analyses identify specific contaminants, selective media can be used, chosen according to the parameter to be addressed and the water composition.
It is preferred when the issue mainly concerns organic substances, or one or a few clearly identified substances, and the aim is to preserve the water’s natural mineral composition.
Compared with ion exchange and membrane processes, it provides more targeted treatment. Activated carbon is not used to reduce hardness, overall salinity or nitrates, and does not replace disinfection.
The choice of medium, bed volume and contact time depends on the substances to be treated, the flow rate and the expected load. The medium must be monitored and replaced or, where possible, regenerated before its treatment capacity is exhausted.
02 — ION EXCHANGE
SOFTENING AND SELECTIVE RESINS
Ion exchange uses resin beads that can retain specific dissolved ions and replace them in a controlled way. Softening removes calcium and magnesium, which are responsible for hardness; for other parameters, such as nitrates or other specific ions, dedicated selective resins can be considered.
It is preferred when analyses identify one or a few ionic parameters to be adjusted and targeted treatment is required without reducing the water’s entire mineral content indiscriminately. When ion exchange is used on lake water or groundwater, pretreatment must take account of solids and turbidity.
Unlike activated carbon, it acts on dissolved ions rather than primarily on organic substances. Compared with reverse osmosis, it provides more selective adjustment, but does not treat all the substances in the water simultaneously.
Resin type and volume, system configuration and regeneration cycles depend on the analyses, flow rate and required continuity of service. Sizing also takes account of regenerant consumption, efficiency monitoring and wastewater management.
03 — MEMBRANE PROCESSES
REVERSE OSMOSIS AND NANOFILTRATION
Membrane processes use pressure to separate water from some of its dissolved substances. Reverse osmosis enables a substantial reduction in salinity and several parameters simultaneously; nanofiltration acts more selectively, particularly on hardness, multivalent ions and certain organic substances.
They are preferred when several parameters need to be reduced simultaneously, conductivity or salinity is high, or water with tightly controlled final characteristics is required. They are considered when selective treatment using activated carbon or resins is insufficient.
Compared with adsorption and ion exchange, they provide broader separation, but require careful pretreatment to protect the membranes. The process produces treated water and a concentrate stream containing the separated substances, which must be managed appropriately. Where necessary, the treated water can undergo pH adjustment or remineralisation.
The choice of membranes, operating pressures, recovery ratio and pretreatment depends on the analyses, flow rate and required quality. Sizing also considers pumping, control instruments, any storage requirements and concentrate management.
IRON, MANGANESE, DISSOLVED GASES AND pH IMBALANCE
Iron and manganese can be present in dissolved form and only become apparent after contact with air, causing colour, deposits and changes in quality. Dissolved gases and pH imbalance can cause odours, corrosiveness or instability in subsequent treatment stages.
Aeration, degassing, pH adjustment and oxidation are technologies used to address these parameters. Their applicability depends on the water analyses and the requirements of the intended use.
Solutions are selected and combined according to the water composition and do not necessarily form consecutive stages.
01 — AERATION AND DEGASSING
DISSOLVED GAS REMOVAL AND OXYGENATION
Aeration promotes exchange between water and air, allowing dissolved gases such as carbon dioxide and hydrogen sulphide to be removed and increasing the oxygen content of the water. With suitable pH and contact time, oxygenation can also initiate the oxidation of dissolved iron, allowing it to be separated by subsequent filtration.
It is preferred when, particularly in groundwater, there are odours associated with hydrogen sulphide, high carbon dioxide concentrations, low oxygen levels or dissolved iron that is readily oxidised by air.
Compared with oxidising reagents, it is a simpler solution when contact with air is sufficient and allows chemical treatment to be limited. However, it does not resolve every situation: manganese often requires specific pH conditions, catalytic filter media or stronger oxidation.
Technology selection and sizing depend on the water composition, flow rate and operating conditions. Any combination with pH adjustment, oxidation and filtration is assessed according to the required result.
02 — pH ADJUSTMENT AND STABILISATION
NEUTRALISING FILTERS AND CONTROLLED DOSING
pH must be assessed together with alkalinity, hardness, carbon dioxide and the water’s mineral composition. Depending on the analyses, adjustment can be achieved using a neutralising filter or controlled dosing of a specific reagent.
A neutralising filter contains carbonate-based media that dissolve gradually, increasing the water’s buffering capacity and reducing its corrosiveness.
It is preferred when the water is acidic and has a low mineral content, its characteristics are reasonably constant and gradual adjustment is sufficient. The medium is consumed during treatment and must be checked and replenished periodically; it may also increase water hardness.
Controlled dosing allows pH to be increased or decreased more precisely. It is preferred when flow rate and water composition vary, a set value must be maintained, or conditions need to be optimised for iron and manganese oxidation or final stabilisation.
Where low pH is mainly caused by excess carbon dioxide, degassing can precede adjustment or reduce the need for it. The adjustment method, sizing and any dosing, mixing and control systems are determined according to the water characteristics and treatment objective.
03 — TARGETED OXIDATION AND FILTRATION
OXIDANTS AND CATALYTIC FILTER MEDIA
Iron and manganese can be present in water in dissolved form and pass through standard mechanical filtration without being retained. In this process, they are oxidised and converted into solid particles, which are then separated in a filter bed. Oxidation and filtration are therefore sized as complementary stages.
Depending on the water composition, pH and required result, oxidation can be achieved using air or oxygen, or controlled dosing of a specific oxidant such as hypochlorite or permanganate. Ozone can also be included in particular situations where stronger action is needed, or where odours, colour and certain organic compounds need to be addressed simultaneously.
The converted substances are then retained by granular bed filters filled with sand and selected catalytic media, including manganese dioxide-based media. Periodic backwashing removes the accumulated precipitates and restores filter bed efficiency.
It is preferred when aeration alone does not provide sufficient oxidation, manganese is present at significant concentrations, the iron load is high, or the water characteristics require a faster, more controllable process.
Compared with simple aeration, targeted oxidation provides stronger, more adjustable action, but requires proper control of pH, dose, contact time and subsequent filtration. Ozone is not a default solution: where used, it requires a dedicated system for generation, contact and residual gas management.
The choice of oxidation process, reactor and filter bed sizing, and the configuration of dosing, backwashing and control systems depend on the analyses, flow rate and required final quality.
MICROORGANISMS AND MICROBIOLOGICAL RISK
Water from a lake, well or spring can contain microorganisms even when it appears perfectly clear and has no noticeable odour or other changes. Rainfall, infiltration, animals, abstraction conditions and seasonal variations can change the microbiological quality of the source over time.
The need for disinfection is assessed according to the water’s intended use and the system conditions. Where required, treatment selection takes account of the analyses, any storage and the distribution network. The water characteristics and any pretreatment must be compatible with the selected disinfection process.
01 — UV DISINFECTION
A PHYSICAL BARRIER WITH NO ADDED SUBSTANCES
UV-C disinfection exposes water to germicidal radiation that can inactivate susceptible microorganisms by preventing them from reproducing. Treatment takes place without adding substances to the water or changing its taste, odour or mineral composition.
The UV reactor is installed downstream of the necessary pretreatment stages. Its sizing takes account of maximum flow rate, water UV transmittance, the required dose and the characteristics of the microorganisms to be controlled. Turbidity and particles can shield microorganisms and reduce their actual exposure to the radiation.
It is preferred when the water has been adequately filtered, final disinfection without chemical dosing is desired, and lasting disinfectant protection in the network is not required.
UV technology leaves no active residual after the treatment point. It therefore does not protect against recontamination that may occur in tanks, pipes or points of use. The lamp, quartz sleeve, sensor and operating conditions must also be checked and maintained over time.
The reactor and any monitoring and control equipment are selected according to the water quality, flow rate and disinfection objective. The configuration also considers maintenance and continuity of service requirements.
02 — CONTROLLED CHEMICAL DISINFECTION
DOSING, CONTACT TIME AND RESIDUAL PROTECTION
When water needs to be stored or distributed through an extensive network, disinfectant activity may need to be maintained beyond the treatment point. In these cases, controlled dosing of a disinfectant authorised for the intended use is considered, such as hypochlorite or chlorine dioxide where applicable.
Effectiveness depends on the dose actually available, pH, temperature, mixing and contact time. Organic substances, iron, manganese or other oxidisable compounds can consume some of the product and must be taken into account in sizing.
It is preferred when the intended use requires microbiological control beyond the treatment point, taking account of storage, the distribution network and the risk of recontamination.
Compared with UV technology, chemical disinfection can provide residual protection, but requires precise dosing and continuous monitoring. Insufficient amounts may fail to achieve the required result, while excessive doses can alter the water characteristics or promote the formation of undesirable by-products.
Where ozone is already included for specific oxidation requirements, it can also contribute to disinfection. However, it does not provide lasting residual protection and requires a dedicated system for generation, contact and management of unreacted gas.
The choice of disinfectant, dosing system, contact volume and control instruments depends on the analyses, flow rate, system configuration and intended use.
LEGIONELLA PREVENTION AND CONTROL
Legionella control involves more than disinfecting water from the source. It requires a specific assessment of the entire building water system: storage, temperatures, recirculation, stagnation, unused pipe sections, outlets, maintenance and monitoring.
For this reason, Fulcor addresses Legionella risk through a dedicated service for drinking water and domestic water systems, defined according to the characteristics and operating conditions of the network.