The SR Scale Remover For Cooling Water Treatment Without Chemicals

1. The SR Scale Remover For Cooling Water Treatment Without Chemicals

2. The problem • Due to evaporation, concentration of salts in the cooling tower water increases constantly. • This is the main reason for the deposition of scale on the elements of the cooling tower and on the piping. • Above process causes a diminuation of the efficiency of the cooling tower.

3. Conventional cooling tower water treatment • Mainly by means of addition of chemicals or by water softening. • Both inhibit the deposition of scale but have disadvantages: - high operating and maintenance costs - large quantities of water used to maintain conductivity within safe limits - they are ecologically dangerous

4. Our Solution : the SR In order to overcome the disadvantages of conventional cooling water treatment we have developed a totally new concept in this field: SR scale remover based on electrolysis.

5. Our Solution : the SR The main advantages of the new method: • The electrical scale remover SR prevents any scale deposits on the elements of the cooling tower • The electrical scale remover SR reduces water blow down and total water consumption to 50% of conventional consumption. • The electrical scale remover SR almost totally excludes maintenance costs. …

6. Our Solution : the SR • The electrical scale remover SR is controlled by a microprocessor based PLC and its valves are electrically activated without the need of compressed air. • The electrical scale remover SR is ecologically safe and environmentally friendly. • The electrical scale remover SR lengthens thelife of the cooling tower.

7. The Device The SR is supplied as a compact, skid mounted device Enclosure Titanium anode Control Panel Circulating Pump Cathode Skid

8. The Electric and Control System • Wide range, stabilized electronic power supply. Input: 230VAC Output: 24VDC – 0-15Amp 24VDC – 1Amp 24VAC – 2Amp • PLC with LCD display and industrial keyboard for operator interface. • Serial port for data transmission to Central Control Room. • Switchgear for the operation of the circulating pump

9. The Circulation Pump • Centrifugal pump with a 2 or 3 HP motor. • Capacity 12 cu.m/hour. • Supplied as part of the device • Circulates both the cooling water and the make-up water through the scale remover

10. The Enclosure • Electrolytic chamber made of cardon steel, coated by a multi-layer baked epoxy.

11. The Anode • Made of titanium mesh with MMO coating. • Has an operating life of 8-10 years.

12. The cathode • Made of stainless steel. • Does not release iron ions into the water. • Elecrically isolated from the enclosure

13. Operation Process • Both the cooling water and the make-up water are continuously circulated through the device. • The process is parallel and independent from the circuit to the heat exchanger, but it may be combined into it. • Regeneration as all the operations are fully automatic and do not need any intervention by operator. • By means of the keyboard and the LCD display the operator is given the possibility to manually perform some operations and change some parameters. …

14. Operation Process • The process is active and full automatic when the SR is connected to power. • There are different modes of operation: - continuous (24 hours). - if at least one of connected towers is operated. - according to day/night time and working days/weekend. • All elements of the scale remover can be operated manually for maintenance and check-up purposes. • At predetermined time intervals and/or when concentration of salts surpasses a certain value, the accumulated scale is removed from the cathode and discharged to the sewage piping. For simulation of the process click here

15. Mode : Normal operation

16. Mode : Normal operation Mode : Regeneration

17. Installation at an Israeli shopping center

18. The chemistry of the process By applying electrical power between the two electrodes made of special non corrosive metal, an electrochemical reaction is activated. Water from the cooling tower basin is circulated into the electrical scale remover SR. Due to the electrolysis process calcium ions are deposited on the cathode as CaCO3 and water is retuned to the cooling tower with lower calcium concentration. The scale potential in the cooling tower water decreases and kept low as long as the electrical scale remover is in operation. The chemical reaction on ST-ASR cathode is as follow: Ca(HCO3)2+2OH’ CaCO3 + 2H2O + CO3¯² Mg(HCO3)2+2OH’ Mg(OH)2 + 2H2O + CO3¯² Water contains metal ions Ca(HCO3) and Mg(HCO3) and itself is breaking up into OH- and H+ in the presence of electric current, the OH- ions are attracted by the cathode (the positive anode) and this is why the reaction with metallic ions takes place on this electrode (the cathode). …

19. The chemistry of the process The reaction is an acid – alkali one. The alkali is the OH- and the acid is the Ca(HCO3)2. The positive ion is scale – CaCO3 On the cathode surface a high alkaline environment is created. This alkaline environment causes the setting of hydroxides and carbonates of low solubility, enhancing formation of less soluble carbonate and hydroxides. On the anode surface, made of cataylic metal oxides, oxygen and clhlorine gas are evolved, producing disinfecting conditions which act against the growth of microorganisms. Based on the results of periodic testing of the chemical composition of the cooling tower water, the intensity of the electrolysis may be increased or decreased according to the system requirements.

20. Technical data • The scale remover is manufactured in following models: …

21. Technicaldata • Power consumption – 2…. 4 kWh depending on model. • Working current – 4….10 Amp. • Economy in water consumption – 25…30% …

22. Technicaldata • Preparations by Customer for installation of SR: • Outlet and inlet piping to tower d=1.5”-2” • 2”piping to sewage • Power supply 3X400V – 16Amp • Dimensions of the device: • Area: 900X800 mm • Height 1400 mm