lpb systemeradication & control of microorganisms,such as legionella pneumpohila bacteria
lpb - product detaillpb system for the continuous and automatic eradication and control of microorganisms, such as legionella pneumophila bacteria, for the prevention of scale (calcium and magnesium carbonates) precipitation in hot and/or cold water circuits and delivery systems, prevention of biofouling, and inhibition of corrosion
uses: hot water production and warm and/or cold water delivery systems
capacities: warm & cold water: 1, 3 & 5 m3/h cold water: 1, 10, 15 & 25 m3/h
users: hot & cold water systems: hotels, hospitals, geriatric and nursing homes, military bases, dormitories, detention centers, housing complexes, apartment buildings, cruise ships and other types of vessels, sport clubs, swimming pools, saunas, jacuzzi’s, whirlpools, turkish and steam baths; in fact any place where a centralized hot water delivery system is used cold water systems: all hvac or climate control systems in public, recreational or commercial buildings where there is a risk of the spread of vapors or aerosols, public fountains, pools and waterfalls, cold storage and supermarket fresh produce displays
lpb - processthe core of the lpb is the reaction tank with tinio electrodes, piston, plunger and drain valve. the operating principle is to move the site of the "breeding ground for bacteria", which is usually located at the bottom of hot water tanks, to a different site, so that the eradication of the legionella pneumophila bacteria can be most efficient. the lpb reaction tank is connected to the hot water delivery system.
when an electrical current is applied to the electrodes, a number of reactions take place:
(1) an alkaline environment (ph > 9.5) is cr-eated next to the lpb reaction tank"s inner walls, which act as a cathode; this highly alkaline environment does not permit legionella bacteria and other microorganisms to survive. (2) next to the anodic electrodes up to 30% of the chlorides, that are naturally present in the water, are transformed into so-called free chlorine or hypochlorite (ocl-); this chlorine level is controllable, varying from 0.2 to 2 ppm; this level permits adequate, additional water disinfection without risking corrosion in the water system. (3) also next to the anodic electrodes radical oxygen, ozone and hydrogen peroxide, are produced, which further contribute to the disinfection of the water inside the reaction tank.
the ph level in the water system does not change: the ph levels of the water at the lpb reaction tank"s water inlet and water outlet are the same
the piston, plunger and drain valve in the lpb reaction tank remove sediments and pollutants from the walls and volume of the tank, so not to cr-eate a breeding ground for the development or proliferation of legionella bacteria and other microorganisms; this removal is fully automatic and can take place once or more times a day. in the existing hot water tank the following items are installed:
(a) a stirring mechanism, release valve and drain, which ensure that there will be no residues at the bottom, which can be a potential breeding ground for the development or proliferation of bacteria or other microorganism.(b) a sacrificial magnesium electrode that cr-eates mg(oh)2 in the water, destroying legionella bacteria and other microorganisms that may accumulate at the bottom of the hot water tank.(c) optionally aluminum electrodes can be installed in the existing hot water tank (see further the g.el system); the aluminum electrodes serve to coat the water tank, piping and tubes with a protective layer of aluminum, thus preventing corrosion and scaling.all the water that circulates through the water delivery system is continuously treated. the whole process is free of chemicals and any other additives. the amount of up to 2.0 ppm free chlorine is within the set drinking water norms in europe, israel, the usa and elsewhere.
legionella pneumophila bacteriamajor factors that promote legionella growth and amplification:stagnant water conditions and/or system design configurations that produce stagnation, such as side-arm and dead-leg pipingwarm water temperatures between 20ºc and 50ºcoptimal growth is at temperatures between 35ºc and 45ºcbulk water ph in the range of 5.0 to 8.5sediment, scale deposits and biofilmcorrosive areas in water heaters, radiators, tanks, valves, pipes and metersmany systems can serve as legionella amplifiers and (aerosol) disseminators:domestic and public hot water systems (boilers, faucets, showerheads)cooling towers, evaporators, condensers, heat exchangersspas, whirlpools, hot tubs, jacuzzis, turkish and steam baths, saunashumidifiers, aerators, compressorshot springs and decorative fountains, ponds and waterfallswater misters in public areas of tropical citiesfresh produce displays with misters in auctions, cold storage and supermarkets
legionella pneumophila bacterialegionella are ubiquitous in all aquatic environments, and capable of existing in waters with varied temperatures, ph levels, and nutrient and oxygen contents.their widespread survival can be attributed to their relationships with other microorganisms. symbiotic existence with algae and other bacteria, particularly in biofilm, increases the availability of nutrients. they also are able to infect protozoa"s and subsequently reproduce within these organisms.these relationships provide protection against inadequate disinfection techniques, even those capable to eradicate and control other microorganisms.legionella infection (legionellosis) occurs from inhalation or aspiration of aerosolized contaminated water, especially by highly susceptible individuals, such as immunosuppressed people, youngsters and the elderly, and fatigued people, such as sporters and travelers. mortality rate of patients with legionellosis is high: 20-30%.
boiling or thermal shockin an emergency situation, best way to purify water that is unsafe because of protozoa, parasites or bacteria, like legionella pneumophila advantagespathogens will be killed at minimum temperature of 70°cdisadvantagesnot fully effective: leaves remnants of microorganisms that can reactivatecauses and accelerates corrosionrisk of severe scalding and burnscannot be used during treatment cycle of the warm water systemcannot be used when toxic metals, chemicals or nitrates are presentconcentrates harmful contaminants that do not vaporizehigh energy consumption relative to yield
chlorination
chlorine, an oxidizing agent, is the most commonly and the oldest chemical used to disinfect water. other agents are sodium hypochlorite, chloramines and chlorine dioxide, each with specific advantages and disadvantages over chlorine.advantageskills most pathogensdisadvantagesrequires proper concentrations and adequate exposure timenot fully effective: leaves remnants of microorganisms that can reactivateineffective against cryptosporidium and giardia protozoa (chlorine only)causes and accelerates corrosionforms hazardous trihalomethanes (carcinogenic properties) and haloacetic acidscan causespontaneous miscarriage in early pregnancy, respiratory problems, including coughing, choking, chest pain, emphysema, bronchitis, and asthma in childrencan cause severe skin and eye irritation, and chemical burns to broken skincan corrode teeth, and damages hair, swimming goggles and bathing suitsdecomposes at high water temperatures
ultraviolet (uv) irradiation
water passes through a clear chamber where it is exposed to ultraviolet light, which has germicidal properties; the irradiation kills or deactivates pathogensadvantagesbacteria are killed with relatively low amounts of radiation; viruses are more resistantleaves no smell or taste to the treated waterrequires very little contact time: seconds versus minutes for chlorinationdisadvantagesnot effective against legionella pneumophila bacteria, cryptosporidia cysts, non-living contaminants, organic chemicals and chlorine how well the uv system works depends on the energy dose that the organism absorbs; if the energy dose is not high enough, the organism’s genetic material may only be damaged rather than disruptednot effective in turbid or colored waterthe uv lamp"s efficiency decreases with age and must be replaced frequentlyleaves no residual product that continues to disinfect beyond the treatment period
ozonation
ozone is a naturally occurring component of fresh air, and can also be cr-eated artificially with an ozone generator; ozone can also be made by electrolytic and chemical reactions. ozone is a very reactive and unstable gas with a short half-life before it reverts back to oxygenadvantagesozone is the most powerful and rapid acting oxidizereffectively kills biological contaminants, given sufficient exposureoxidizes and precipitates iron, sulfur, and manganese, so they can be filtered outoxidizes and breaks down organic chemicals that cause odor and taste problemsvanishes without trace once it has been useddisadvantagescr-eates formaldehyde and bromate that can be a health hazardwhen used for water storage or large volume water distribution, no residual disinfectant remains, so chlorine or other disinfectants must be added to minimize microbial growthineffective in removing dissolved minerals and salts
copper-silver ionization
copper-silver ionization is an electrolytic process (like the scp system), that releases 0.1 to 0.5 ppm cupper (cu) ions and 0.01 to 0.05 ppm silver (ag) ions in the water streamadvantageseffectively deactivates biofilm and most microorganisms, to a lesser extent the stronger bacteria, such as legionella pneumophilalonger residual effect than most chemical disinfectantsdisadvantagescu ions promote scalinghard water or biofouling decrease release of cu and ag ions, impacting treatment efficacyefficacy depends on the ph value of the water: the higher the ph, the less effectivewhen dissolved solid concentrations are high, ag will precipitate.ag ions easily react with chlorines and nitrates, causing them to no longer be effectivesome species of microorganisms can become resistant to ag ionswhen little water is used, or the water flow is too slow, or when there are dead-end points in the water system, the effectiveness to disinfect the entire system decreases, and the risk of re-contamination increases substantially
anodic oxidation
anodic oxidation is an electrolytic process, using electrodes placed in-line creating oxidation around the anodes in the water flowadvantagesclaims to deactivate biofilm and microorganisms (data vary dramatically between products)produces disinfectants: free chlorine (0.2 to 2 ppm), radical oxygen, atomic oxygen, ozone and hydrogen peroxidedisadvantagesmost systems require the addition of salts to produce adequate free chlorinedesign (in-line) may not always allow sufficient time for adequate disinfectionexcept for chlorine, the other disinfectants are highly volatile and dissolve extremely fastsome systems switch polarity between electrodes, which can cr-eate scaling on the electrodes, thereby decreasing efficiencyefficacy depends on the ph value of the water: the higher the ph, the less effectivesome species of microorganisms can reactivate downstreamwhen little water is used, or the water flow is too slow, or when there are dead-end points in the water system, the effectiveness to disinfect the entire system decreases, and the risk of re-contamination increases substantiallynote: the est and lpb use this same anodic oxidation process, but inside a reaction tank, giving better and controllable results
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