The LOTUS AIR generator produces concentrated chlorine dioxide on site, in an automatic cycle and under safe conditions, from two precursors: hydrochloric acid and sodium chlorite. The product is transferred to an integrated storage tank, from which it is drawn by one or more dosing pumps.
A highly effective oxidant and disinfectant: it acts on all organic species, including Legionella and biofilm, and oxidises iron and manganese. It is used in water supply network storage tanks, in hot water systems of hotels, hospitals and swimming pools, in industry (washing of bottles, fruit and vegetables, cooling towers), in livestock farming and in agriculture.
Insight: the disinfectants used →It exerts its disinfecting action in approximately 5 minutes of contact and remains in solution for a long time, reaching even the most remote or stagnant areas of the system, with a residual effectiveness greater than that of other disinfectants.
It destroys biofilm, which offers shelter and nourishment to bacteria such as Legionella, and counteracts its re-formation, with an effectiveness considerably greater than that of sodium hypochlorite.
It does not alter the odour, taste or colour of the water, is active between pH 4 and 10, does not form trihalomethanes or organohalogen compounds and does not react with ammonia, thus avoiding the formation of chloramines.
Recommended concentration against Legionella: 0.1 – 1.0 mg/l, depending on the system, the water and the level of contamination. In the event of high contamination, a temporary flushing of the network with 5 – 10 mg/l (shock treatment) is possible, prohibiting the use of hot water and subsequently bringing the concentration back to operating values.
Chlorine dioxide is an unstable compound, subject to rapid degradation: it is used in stabilised form or generated directly at the point of use.
Insight: chlorine dioxide →Stabilised chlorine dioxide is activated by the user with a second product and must be used within approximately 30 days, with decreasing effectiveness; after the container has been opened, chlorites and chlorates may form. It is dosed with dosing stations or with the LDsCL system.
LDsCL system →The precursors, hydrochloric acid (HCl 9%) and sodium chlorite (NaClO2 7.5%), cost considerably less than stabilised chlorine dioxide; generation in small quantities ensures an always fresh product, with virtually no by-products.
LOTUS systems, examined by INAIL (Italian National Institute for Insurance against Accidents at Work) technicians, have received an opinion of suitability for the safe management of water systems and for the prevention of Legionella: their installation constitutes an improvement in workplace safety and hygiene conditions and makes it possible to benefit from a reduction of up to 28% in the annual INAIL premium.
Inside the reactor, the water and the two precursors react, forming chlorine dioxide.
Water, free of free chlorine, is introduced first: the solenoid valve feeds it into the reactor, where the reaction takes place.
Pump 1 adds the first precursor, 9% hydrochloric acid (HCl), a molecule consisting of one hydrogen atom bonded to one chlorine atom.
Pump 2 adds 7.5% sodium chlorite (NaClO2), which in solution dissociates into sodium ion and chlorite ion, consisting of one chlorine atom and two oxygen atoms.
In the 1-litre reactor, at ambient pressure, the acid converts the chlorite into chlorine dioxide in 15 minutes; sodium chloride and water are formed as secondary products.
A second water feed dilutes the chlorine dioxide (ClO2) to 2 g/l; the solution is then transferred to the storage tank, available to the dosing pumps.
The reaction: 5 NaClO2 + 4 HCl → 4 ClO2 + 5 NaCl + 2 H2O.
Fully automatic cycles in a 1-litre reactor at ambient pressure, which can be emptied by opening a tap. The reaction is continuously monitored: in the event of an anomaly the controller empties the reactor and generates an alarm.
The solenoid valve fills the reaction tank with water up to level 1.
Pump 1 adds hydrochloric acid up to level 2.
Pump 2 adds sodium chlorite up to level 3.
15-minute reaction, forming chlorine dioxide.
Water feed up to level 4: the chlorine dioxide concentration is brought to 2 g/l (2,000 ppm).
The contents of the reactor are transferred to the storage tank.
Once the transfer to the storage tank is complete, the transfer valve closes.
From the storage tank, one or more dosing pumps inject the chlorine dioxide, also into separate systems.
Reaction tank, transfer valve, storage tank, emptying valve (discharges the chlorine dioxide in the event of an anomaly), dilution water solenoid valve (water free of free chlorine), pumps for hydrochloric acid, sodium chlorite and chlorine dioxide, stainless steel sampling cell with amperometric probe, controller, multifunction valve (pressure, safety, anti-siphon and drain) and activated carbon filter for the reaction gas.
It monitors the chlorine dioxide concentration in the air of the room: when the set point is exceeded, it generates an alarm and stops generation and dosing. Measuring range 0.03 – 5.00 ppm; capsule replacement every 2 years.
Dosing of a constant, preset quantity of chlorine dioxide.
The quantity to be dosed is set for each litre measured by the pulse-output water meter (turbine or Woltmann, from 1/2" to 8").
Water meters →
In proportion to the signal from a water meter, a PLC or other equipment.
The set point is set in mV; the Redox electrode regulates dosing until the set value is reached.
The residual is set in mg/l: the self-cleaning 3-electrode amperometric cell, temperature-compensated and also suitable for hot water, regulates dosing.
SCL17 cell →
The water meter installed on the make-up line controls a pre-dosing; the cell on the circuit activates a second pump for fine correction up to the set point. The water meter can also control a pump for the film-forming inhibitor.
Typical plant configurations, from the simplest to the most complete.
The pulse-output water meter installed on the line controls chlorine dioxide dosing in proportion to the volume of water; injection takes place in the static mixer; a dedicated pump also doses the antiscalant.
Measurement of the residual chlorine dioxide is added to proportional dosing: the water sampled downstream of the injection point passes through the LOTUS measuring cell and is conveyed to the drain.
Chlorine dioxide is dosed into the storage tank, where the measurement keeps its concentration constant; downstream of the booster pump, the water meter controls antiscalant dosing on the line to the points of use.
The LOTUS doses chlorine dioxide into the incoming cold water in proportion to the water meter and, by means of a second pump controlled by the measurement, into the recirculation of the hot water storage.
| LOTUS AIR 10 | LOTUS AIR 30 | LOTUS AIR 60 | |
|---|---|---|---|
| Maximum chlorine dioxide output | 10 g/h | 30 g/h | 60 g/h |
| Maximum daily output | 240 g | 720 g | 1,440 g |
| Chlorine dioxide concentration | 2 g/l | 2 g/l | 2 g/l |
| Maximum consumption per reagent | 0.25 l/h | 0.75 l/h | 1.5 l/h |
| Maximum dilution water pressure | 2 bar | 3 bar | 3 bar |
| Maximum operating pressure | 8 bar | 5 bar | 5 bar |
| Reagents | HCl 9% and NaClO2 7.5% | HCl 9% and NaClO2 7.5% | HCl 9% and NaClO2 7.5% |
| Dimensions (W × H × D) | 600 × 900 × 285 mm | 685 × 1,390 × 460 mm | 685 × 1,390 × 460 mm |
| Weight | 55 kg | 85 kg | 85 kg |
For pressures above the maximum operating pressure, an external pump is used. Operating temperature 0 – 45 °C.
The controllers can be remotely controlled bidirectionally (read and write) from the web portal, from PC, tablet and smartphone: viewing of measurements, modification of set points, dosing and alarms, receipt of alarms and download of logs. Alternatively, integration into your PLC via Modbus is possible.
Connection to the web portal via network cable: measurements, set points, dosing and alarms accessible from PC, tablet and smartphone.
Wireless connection to the web portal, with the same functions as the cable connection.
Connection via the cellular network for installations without a local network, with alarm notification by SMS or e-mail.
Integration into your PLC via serial port.
Integration into your PLC or SCADA via Ethernet network.
Current signal proportional to the measured value, for remote monitoring or for controlling pumps and other instrumentation.
A single account brings together all registered installations, each with its own devices: the web portal, free of charge and with no subscription, can be accessed from PC, Mac, tablet and smartphone and allows every parameter to be both viewed and changed, with an encrypted connection and protected access.
On a single screen: probe readings, chemical levels, pump activation thresholds and active alarms, with the status of installations and devices (normal, warning, alarm, standby, not connected).
Installations appear on an interactive map with their status and open with a click; for each one, the local weather conditions and temperature are also shown.
Archive of measurements and alarms, available for consultation at any time with charts and numerical reports exportable in Excel format.
Alarm thresholds for readings, dosing, faulty probe and out-of-range readings, with notification by e-mail or SMS depending on the communication system; a warning is also issued when an installation remains disconnected beyond the set time.
Remote modification of the set points, of the dosing pump activation thresholds and of the corresponding hourly flow rate.
Status of relays, pulse outputs, digital inputs and current outputs, with the name assigned to each connection.
Tasks are scheduled by installation or by device and assigned to technicians; a reminder is sent by e-mail two days before the due date. Each task is shown as scheduled, due, overdue or completed.
The main account has full access and creates the technicians’ accounts, each enabled only for the assigned installations and devices; the last login and activity of each technician are visible.
Reports on devices, tasks and technicians, downloadable in PDF or CSV with the customer’s logo; the log keeps the history of operations and disconnections.
Logo, main colour and light or dark theme; the tiles on the main screen can be rearranged by dragging them. Two installations can be displayed side by side for comparison.
Each device is added through a guided procedure: the model is recognised automatically and associated with the installation, together with the technician to be contacted.
As an alternative to the portal, the Modbus RTU or TCP/IP port allows integration into the plant supervision system.
600 × 900 × 285 mm, 55 kg.
685 × 1,390 × 460 mm, 85 kg.
Raw water from wells and springs, private and from public water supply networks.
Insight: well water →Domestic water circuits of hotels and accommodation facilities, hospitals, care homes and swimming pools.
Process water, food washing, cooling towers.
Municipal and industrial wastewater.
Components complementary to the generator for dosing chlorine dioxide at one or more points.
For dosing the chlorine dioxide produced, also with several pumps on separate circuits, and the film-forming inhibitor.
Dosing pumps →
Installed on the make-up water pipe, it measures the volume of water and controls dosing.
Water meters →
For the precursors, with suction lance and level probe for signalling when the chemical has run out.
Lances →
It injects the chlorine dioxide into the pipe and prevents backflow of the water.
Injection →
It feeds the dilution water into the reactor.
It ensures the dispersion of the chlorine dioxide in the water and protects the pipe from direct contact with the product.
Mixers →
It attenuates the pulsations of the dosing pump.
Dampeners →Systems are supplied pre-assembled and tested, in the form best suited to the plant room: on a panel, in a cabinet or on a skid (with cover, in a box or on a frame), also tailor-made. Some examples.
Controller, pumps, probe holder and accessories mounted and wired on a wall panel.
System panel and chemical tanks housed in a single cabinet.
Pipework, pumps and electrical panel in a wall cabinet with door.
Skid with raised stainless steel frame and protective PMMA cover.
Skid enclosed in a box with door, with the chemical tanks at the base.
Skid on a frame with doors, pre-assembled and ready for connection.
Dosing pump mounted directly on the tank: the most compact solution.
Wall installation in the plant room, with the chemical tanks on the floor.
Pumps, controllers or components supplied by the customer can also be fitted, with custom dimensions, back panel and electrical panel. Dosing stations and skids →
For chlorine and other disinfectants the basic solution is the dosing station; to dose according to the concentration actually present in the water, measuring controllers are used.
The simplest solution: the pump doses at a constant rate or in proportion to the volume of water measured by the pulse-output water meter.
Details →
Dosing based on the Redox potential of the water: an economical solution, based on an indirect measurement.
Details →
The amperometric cell directly measures the disinfectant concentration in mg/l, ensuring maximum dosing accuracy.
Details →
Simultaneous management of two parameters, for example pH and chlorine, with a single controller.
Details → Management of up to 10 parameters and of all the pumps in the installation, with touch screen and remote control as standard.
Details → Chlorine dioxide generator: it produces the disinfectant on site from the precursors and doses it in proportion to the water meter or to the measured residual.
Tell us the water flow rate to be treated and the characteristics of the installation: we will propose the most suitable model, pumps and dosing mode.
Call or write to us: a technician will reply with a tailored proposal of controllers, pumps, probes and accessories.