Advantages

Chlorine

Used in gaseous state, requires extremely strict safety control.

• Efficient oxidant and disinfectant.
• Efficiently eliminates unpleasant taste and odor.
• Presence of after effect.
• Prevents algae growth and biofouling.
• Destroys organic compounds (phenols).
• Oxidizes iron and manganese.
• Destroys hydrogen sulphide, cyanides, ammonia and other nitrogen compounds.

• Very strict safety requirements during transportation and storage.
• Potential health effect in case of leakage.
• Formation of by-products of disinfection – trihalomethanes.
• Formation of bromates and bromorganic by-products in presence of bromides.

Sodium hypochlorite

Used in liquid state (market concentration 10-12%), may be generated on-site using electrochemical method.

• Efficient against the majority of pathogenic microorganisms.
• Relatively safe during storage and use.
• Does not require transport and storage of dangerous chemicals when generated on-site.

• Inefficient against cysts (Giardia, Cryptosporidium).
• Shows low activity after a long storage period.
• Potential hazard of gaseous chlorine emission during storage.
• Formation of by-products of disinfection, including trihalomethanes, such as bromoform and bromates in presence of bromides.
• When produced on-site, either should be used immediately or, for storage purposes, special measures should be taken to clean the source water and salt from heavy metal ions.
• During storage of NaClO with active chlorine concentration over 450 mg/l and pH over 9, chlorates are being accumulated.  

Chlorine dioxide

Generated exclusively on-site. At present chlorine dioxide is considered to be the most efficient disinfectant among chlorine-containing agents for the treatment of high pH water.

• Efficient in low doses.
• Does not generate chloramines.
• Does not facilitate trihalomethane generation.
• Destroys phenols – sources of unpleasant taste and odor.
• Efficient oxidizer and disinfectant of all types of microorganisms, including cysts (Giardia, Cryptosporidium) and viruses.
• Does not generate bromates and bromorganic by-products of disinfection in presence of bromides.
• Facilitates removal of iron and manganese by rapid oxidation and oxides precipitation.

• Must be generated exclusively on-site.
• Requires transportation and storage of highly inflammable source substances.
• Generates chlorates and chlorites.
• In combination with some materials and substances produces unpleasant taste and odor.

Chloramine

Chloramine is obtained from reaction of ammonia with active chlorine compounds and used as disinfectant having prolonged action.

• Stable and sustained aftereffect.
• Helps to eliminate unpleasant taste and odor.
• Low generation rate of trihalomethanes and other by-products of disinfection.

• Lower disinfection efficiency and oxidation capacity as compared to chlorine and hypochlorite.
• Inefficient against cysts (Giardia, Cryptosporidium).
• High doses and long contact time is required for disinfection.
• Dangerous for dialysis patients, because it can penetrate with dialyzer membrane and damage erythrocytes.
• Generates nitrogen-containing by-products.

Ozone

Ozone has been used for decades in some European countries for disinfection, discoloration,   taste and odor control.

• High-efficiency disinfectant and oxidant.
• Extremely high efficiency against viruses.
• The most effective disinfectant against Giardia, Cryptosporidium, as well as any other pathogenic flora.
• Removal of water turbidity.
• Removal of foreign taste and odor.
• No generation of chlorine-containing trihalomethanes.

• Generates by-products, including aldehydes, ketones,  organic acids, bromates (in presence of bromides), peroxides, acetic-bromine acid.
• Requires the use of biologically active filters for removal of generated by-products.
• Does not produce residual disinfecting action.
• Requires high initial equipment investments.
• Requires considerable expenses for operators’ training and device maintenance.
• Reacts with compound organic matter, decomposing them into fragments which appear to be a growth medium for microbes in water distribution systems.

Ultraviolet

Ultraviolet irradiation of water to destroy various types of microorganisms.  

• Storage and transport of chemicals is not required.
• No by-products generated.
• Efficient against cysts (Giardia, Cryptosporidium)

• Does not produce residual effect.
• Considerable equipment and maintenance cost.
• High operational (power consumption) cost.
• Disinfecting action depends on water turbidity, hardness (sediment formation on the lamp surface), formation of organic contamination deposits on the lamp surface, as well as power network oscillations influencing wave length changes.
• No possibility of operation control over water disinfection efficiency.

Oxidant solution generated by AQUACHLOR-M device

Generation of wet gaseous mixture of oxidants – chlorine, chlorine dioxide, ozone, hydroperoxide compounds – by means of electrochemical synthesis from sodium chloride solution.

• Efficient in low doses.
• Does not facilitate generation of trihalomethanes.
• Destroys phenols – source of unpleasant taste and odor.
• Efficient oxidizer and disinfectant against all types of microorganisms including cysts (Giardia, Cryptosporidium), viruses, mycobacteria, spores, microbial toxins.
• Does not generate bromates and bromorganic by-products of disinfection in presence of bromides.
• Facilitates removal of iron and manganese from water by rapid oxidation and oxides precipitation.
• Helps to remove turbidity.
• Removes foreign odors and tastes.
• Does not require transport and storage of dangerous chemicals.