Chlorine Demand
Calculate the chlorine demand of a water, demand = applied dose − chlorine residual, subtracting the measured chlorine residual (mg/L) from the applied chlorine dose (mg/L). The result, in mg/L, is the chlorine consumed by organic matter, ammonia, iron, manganese and other reducers before free chlorine remains for disinfection. Knowing the demand is essential to dose chlorine correctly and keep an adequate residual in the network without waste or underdosing. Enter the applied dose and the measured residual.
Resultado
—
Demanda de cloro
Quando se adiciona cloro a uma água, nem todo ele fica disponível para desinfecção: parte é imediatamente consumida em reações com matéria orgânica, amônia, ferro, manganês, sulfetos e outras substâncias redutoras presentes. A demanda de cloro é justamente essa parcela consumida, e se calcula por diferença: demanda = dose aplicada − cloro residual, ambas em mg/L. Só depois de satisfeita a demanda é que sobra cloro livre residual capaz de inativar microrganismos e proteger a água ao longo da rede de distribuição. Conhecer a demanda é o que permite dosar corretamente: uma dose insuficiente não deixa residual e compromete a segurança bacteriológica; uma dose excessiva desperdiça produto e pode gerar gosto, odor e subprodutos indesejados como trihalometanos. Em águas com muita amônia, a curva de cloração apresenta o fenômeno do breakpoint (ponto de quebra), em que o residual cai antes de voltar a subir como cloro livre. Informe a dose aplicada e o cloro residual medido.
Related Tools
Coagulant Dosing
Calculate the coagulant consumption of a water treatment plant, consumption = flow × dose ÷ 1000, multiplying the treated flow (m³/day) by the coagulant dose (mg/L) set by jar test. The result, in kg/day, sizes the storage, dilution and dosing pumps for products such as aluminium sulphate, ferric chloride or PAC, ensuring efficient coagulation of colloidal particles. Enter the treated flow and the coagulant dose.
Corrosion Inhibitor Efficiency
Calculate the efficiency of a corrosion inhibitor, η = (CR₀ − CR_inh) ÷ CR₀ × 100%, comparing the corrosion rate without inhibitor (CR₀) with the rate in its presence (CR_inh). The result, in %, measures how much the inhibitor slowed corrosion — the standard indicator to evaluate and compare inhibitors in laboratory tests (mass loss, polarization or impedance). Effective inhibitors form protective films on the surface and reach efficiencies above 90%. It is widely used in boiler water treatment, cooling systems and well acidizing. Enter the corrosion rates without and with inhibitor.
Hydraulic Retention Time (HRT)
Calculate the hydraulic retention time (HRT) of a reactor or tank, HRT = volume ÷ flow, dividing the working volume (m³) by the influent flow (m³/h). The result, in hours, is the average time the liquid stays in the unit and is decisive in designing clarifiers, anaerobic reactors, lagoons and aeration tanks: short times prevent reactions or settling from completing, while long times raise cost and footprint. Enter the working volume and the inlet flow.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.