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    Water Treatment Dosing Calculators

    Four working calculators our technical team uses every day — with the formulas in the open so you can check the arithmetic. Results are planning estimates; for a dosing programme matched to your water analysis, send it over and we'll run it properly, free of charge.

    Chlorination Feed Rate

    How much product to feed for a target free-chlorine dose.

    1.54 kg/day
    product feed
    46 kg/month
    ≈ 30-day consumption

    kg/day = dose × flow ÷ (1000 × available-Cl fraction)

    Get a Calcium Hypochlorite quote

    Glycol Freeze Protection

    Concentration and glycol volume for a target freeze point.

    40% v/v
    freezes at ≈ -22.3 °C
    2,000 L glycol
    + 3,000 L water

    Approximate table values — verify the final mix with a refractometer. Use inhibited glycol matched to system metallurgy.

    Get a glycol quote

    Cooling Tower Cycles & Blowdown

    Evaporation, blowdown, make-up and inhibitor feed from cycles of concentration.

    4.59 m³/h
    evaporation
    1.15 m³/h
    blowdown
    5.74 m³/h
    make-up
    2.75 kg/day
    inhibitor feed

    E ≈ 0.00153 × R × ΔT · B = E ÷ (C − 1) · feed = ppm × B ÷ 1000

    Get a cooling-water programme quote

    RO Antiscalant Consumption

    Feed rate and monthly consumption from dose and feed flow.

    300 g/h
    feed rate
    7.2 kg/day
    daily
    216 kg/month
    ≈ 30 days

    g/h = dose (mg/L) × feed flow (m³/h) — dose from a projection against your water analysis (typ. 2–4 mg/L)

    Get an antiscalant quote + free projection
    Engineering note. These calculators give planning-grade estimates using industry-standard formulas (shown under each tool). Actual dosing depends on your water analysis, temperature, materials and control regime — Global Chemicals LLC's technical team reviews all of that at no cost when you request a programme. Formulas may be reproduced with attribution and a link to this page.

    Glycol freeze-protection reference (Oman chilled-water systems)

    Approximate freeze point by glycol volume concentration. Monoethylene glycol (MEG) is the standard industrial choice; monopropylene glycol (MPG/PG) is used where incidental food or potable contact is possible.

    Glycol concentration (vol %)MEG freeze pointMPG / PG freeze point
    10%-3.4 °C-2.9 °C
    20%-7.9 °C-7.1 °C
    30%-14.1 °C-12.7 °C
    40%-22.3 °C-21.1 °C
    50%-33.8 °C-33.5 °C
    60%-48.3 °C-51.1 °C

    Chlorine product strength comparison

    Available chlorine determines how much product is needed per mg/L of dose. Product feed (kg/day) = dose (mg/L) × flow (m³/day) ÷ (1000 × available chlorine fraction) — so at a fixed dose, product consumption scales inversely with the strength below.

    ProductAvailable chlorinekg/day at 2 mg/L into 500 m³/day
    Calcium hypochlorite granules (65% av. Cl)65.0%1.54 kg/day
    Calcium hypochlorite granules (70% av. Cl)70.0%1.43 kg/day
    Sodium hypochlorite solution (12.5% av. Cl)12.5%8 kg/day
    Sodium hypochlorite solution (15% av. Cl)15.0%6.67 kg/day
    TCCA tablets/granules (90% av. Cl)90.0%1.11 kg/day

    Liquid sodium hypochlorite figures are kg/day of solution; divide by its density (~1.2 kg/L) for litres. Tables may be reproduced with attribution and a link to this page.

    Frequently Asked Questions

    Product feed (kg/day) = target dose (mg/L) × flow (m³/day) ÷ (1000 × available chlorine fraction). Example: dosing 2 mg/L into 500 m³/day using 65% calcium hypochlorite needs 2 × 500 ÷ (1000 × 0.65) ≈ 1.54 kg/day of product. For liquid sodium hypochlorite the same formula gives kg/day of solution; divide by its density (~1.2 kg/L) for litres.

    For chilled-water and process loops, typical protection targets map to approximate volume concentrations: -8 °C ≈ 20%, -14 °C ≈ 30%, -22 °C ≈ 40% for MEG (propylene glycol runs slightly higher for the same protection). Glycol volume = system volume × concentration. Always verify the final mixture with a refractometer, and use inhibited glycol matched to the system metallurgy.

    Evaporation E (m³/h) ≈ 0.00153 × recirculation rate (m³/h) × ΔT (°C). Blowdown B = E ÷ (C − 1), where C is cycles of concentration. Make-up = E + B (drift neglected). Example: 500 m³/h recirculation with a 6 °C range at 5 cycles gives E ≈ 4.6 m³/h and B ≈ 1.15 m³/h. Inhibitor feed (kg/day) = target residual (mg/L) × blowdown (m³/day) ÷ 1000.

    Most RO antiscalants dose at 2–4 mg/L into the membrane feed stream — the exact figure comes from a projection run against your feed-water analysis. Feed rate (g/h) = dose (mg/L) × feed flow (m³/h). A 100 m³/h train at 3 mg/L consumes 300 g/h ≈ 7.2 kg/day ≈ 216 kg/month. We run projections free of charge against your water analysis.