NanoDose™ Chlorine Dosing Kit

Sodium Hypochlorite Dosing to Remove Iron & Manganese

When added to raw groundwater, sodium hypochlorite (NaOCl) dissolves and forms hypochlorous acid (HOCl). This acts as a powerful chemical oxidant. It changes dissolved, invisible metal ions into solid, filterable particles by taking away their electrons.

Oxidation of Iron and Manganese

• Iron (Fe2+ to Fe3+): Sodium hypochlorite rapidly oxidizes soluble ferrous iron into insoluble ferric iron. This forms solid ferric hydroxide flakes that are easily caught by standard sediment filters.
• Manganese (Mn2+) to (Mn4+): It oxidizes soluble manganous ions into insoluble manganese dioxide (\(MnO_{2}\)) particles. Manganese reacts more slowly than iron and often needs a higher pH level (around 7.2 to 8.5) to precipitate completely.
• Media Regeneration: Sodium hypochlorite re-oxidizes and restores the active chemical coating on specialty filter beds like manganese greensand.

Oxidation of Other Chemical Contaminants

• Hydrogen Sulfide (H2S): It converts toxic and smelly hydrogen sulfide gas into harmless, solid elemental sulfur or soluble sulfate particles, removing rotten-egg odors.
• Inorganic Sulfides and Sulfites: It oxidizes reduced sulfur species into stable sulfates, removing their chemical oxygen demand.
• Organic Compounds: It breaks down certain dissolved natural organic materials and coloring agents through direct electron-transfer oxidation, reducing overall water color.

Antibacterial Properties

Sodium hypochlorite (NaOCl) is powerfully antibacterial and serves as a primary sanitiser and broad-spectrum disinfectant. It destroys bacteria, viruses, fungi, and algae by oxidative cellular lysis. In raw groundwater, it rapidly inactivates native microbial constituents, shifting community structures, disrupting cell membranes, and potentially creating disinfection by-products if excess organic or inorganic compounds are present.

Antimicrobial Spectrum of Sodium Hypochlorite

• Bacteria: Highly effective against vegetative cells (such as Escherichia coli and coliforms) by breaking down cell walls and metabolic enzymes
• Viruses: Inactivates both lipid-coated and non-lipid-coated viruses (including hepatitis A and norovirus) via genomic and structural disruption.
• Fungi & Yeasts: Eradicates various fungal isolates and yeasts (such as Candida albicans).
• Algae & Protozoa: Controls algae and certain parasites, though specialized cysts like Cryptosporidium show higher resistance.

Effects on Microbial Constituents in Raw Groundwater

• Cell Lysis and Inactivation: Oxidizing hypochlorous acid (HOCl) penetrates microbial membranes in the groundwater, causing immediate enzymatic failure and cell death.
• Population Shifts: Shifts the natural, diverse indigenous microbiome of the raw water toward a heavily suppressed or total non-culturable state.
• Organic Matter Interaction: Reacts with dissolved organic carbon, amino acids, and cellular debris, which can consume the active chlorine demand and form disinfection by-products (DBPs) like trihalomethanes.
• Biofilm and EPS Disruption: Breaks down extracellular polymeric substances (EPS) produced by sessile microbial clusters, though high or uneven dosing can leave resilient fragments or allow regrowth if a proper residual isn't maintained.