Degrees | ||
° | ||
minutes | ||
seconds | ||
Decimal degrees | ||
° | ||
Radians | ||
rad | ||
π.rad |
Metric | ||
m² | ||
mm² | ||
cm² | ||
km² | ||
ha | ||
US | ||
in² | ||
ft² | ||
mi² |
Conductivity | ||
µS/cm | ||
mS/cm | ||
S/cm | ||
S/m (A/V/m) | ||
µmho/cm | ||
mmho/cm | ||
mho/cm | ||
mho/m | ||
abmho/m | ||
Resisitivity | ||
MΩ.cm | ||
Ω.m (V/A.m) | ||
Ω.cm |
Metric | ||
µg/L | ||
mg/L | ||
g/cm³ | ||
g/L | ||
kg/m³ | ||
mg/mL | ||
US | ||
lb/in³ | ||
lb/ft³ | ||
lb/gal |
Metric | ||
J | ||
Wh | ||
kWh | ||
cal | ||
kcal | ||
N.m | ||
kgf.m | ||
US | ||
BTU (iso) | ||
hp.h | ||
lbf.ft | ||
lbf.in | ||
Eq. ton of Coal | ||
Eq. ton of Oil |
Metric | ||
kg/s | ||
kg/min | ||
kg/h | ||
kg/day | ||
g/min | ||
US | ||
lb/s | ||
lb/min | ||
lb/h | ||
lb/day |
Metric | ||
m³/s | ||
m³/min | ||
m³/h | ||
m³/day | ||
L/s | ||
L/min | ||
L/h | ||
L/day | ||
ML/day | ||
US | ||
gal/s (gps) | ||
gal/min (gpm) | ||
gal/h (gph) | ||
gal/day (gpd) | ||
Mgal/day (mgd) | ||
ft³/min (cfm) | ||
ft³/s (cfs) | ||
oil barrel/day (bpd) |
Metric | |
L/(m².h) | LMH |
m³/(m².day) | m/day |
m³/(m².h) | m/h |
m³/(m².min) | m/min |
m³/(m².s) | m/s |
US | |
gal/(ft².day) | GFD |
gal/(ft².h) | GFH |
gal/(ft².min) | GFM |
gal/(ft².s) | GFS |
ft³/(ft².day) | ft/day |
ft³/(ft².h) | ft/h |
ft³/(ft².min) | ft/min |
ft³/(ft².s) | ft/s |
Metric | ||
N | ||
kN | ||
kgf | ||
dyn | ||
US | ||
lbf | ||
pdl |
Hardness | ||
mg/L CaCO_{3} | ||
meq/L | ||
mmol/L | ||
°dH | ||
°e | ||
°fH | ||
gpg |
Metric | ||
m | ||
cm | ||
mm | ||
µm | ||
nm | ||
km | ||
US | ||
in | ||
mil | ||
ft | ||
yd | ||
mi |
Metric | ||
kg | ||
g | ||
mg | ||
µg | ||
metric ton | ||
US | ||
lb | ||
oz | ||
ton |
Metric | ||
W (J/s) | ||
kW | ||
cal/s | ||
kcal/h | ||
kgf.m/s | ||
hp(M) - Metric | ||
US | ||
hp (I) - Mechanic/Hydraulic | ||
hp (S) - Boiler | ||
hp (E) - Electric | ||
BTU/s |
Metric | ||
bar | ||
Pa | ||
kPa | ||
kg/cm² (kgf) | ||
atm | ||
mH_{2}O | ||
mmHg | ||
US | ||
psi | ||
ftH_{2}O | ||
inH_{2}O | ||
inHg |
Metric | ||
m/s | ||
m/min | ||
m/h | ||
m/day | ||
km/h | ||
cm/h | ||
cm/min | ||
cm/s | ||
US | ||
in/h | ||
in/min | ||
in/s | ||
ft/h | ||
ft/min | ||
ft/s | ||
mi/h (mph) | ||
mi/min (mpm) |
Metric | ||
°C | ||
Kelvin | ||
US | ||
°F |
Composite¹ | ||
days | ||
hours | ||
minutes | ||
seconds | ||
Decimal² | ||
days | ||
hours | ||
minutes | ||
seconds |
^{1} Each input represents a component of the date/hour format: [dd][hh]:[mm]'[ss]''
^{2} Each input represents the sum of days, hours, minutes and seconds converted to the same base.
Metric | ||
m³ | ||
L | ||
mL | ||
µL | ||
pL | ||
US | ||
gal (US) | ||
gal (Imperial) | ||
in³ | ||
ft³ | ||
fl oz | ||
oil barrel |
Nominal pipe size / DN | |||
Wall thickness designation | |||
Equivalent thickness designations* | |||
None |
|||
External diameter | |||
mm | in | ||
Internal diameter | |||
mm | in | ||
Internal area | |||
mm² | in² | ||
Wall thickness | |||
mm | in |
*Other designations with the same diameters and wall thickness.
Nominal Pipe Size dimensions from the ASME Standards B36.10M, ASME B36.19M and ISO 6708. Valid for Stainless Steel, Ductile Iron, PVC and CPVC pipes.
Desired outputs | ||||
Angle 1, Angle 2, Angle 3 | ||||
Side 2, Side 3, Angle 1 | ||||
Side 3, Angle 1, Angle 2 | ||||
Side dimensions | ||||
Side 1 | mm | in | ||
Side 2 | mm | in | ||
Side 3 | mm | in | ||
Angles* | ||||
Angle 1 | ° | rad | ||
Angle 2 | ° | rad | ||
Angle 3 | ° | rad | ||
Perimeter | ||||
mm | in | |||
Area | ||||
mm² | in² | |||
m² | ft² |
*Angles are named according to the opposite side name (example: A1 refers to the side S1).
Flow | ||||
Nm³/h | ft³/min | |||
Air density at NTP | ||||
kg/m³ | lb/ft³ | |||
Intake pressure* | ||||
bar | psi | |||
Output pressure* | ||||
bar | psi | |||
Temperature | ||||
°C | °F | |||
Mechanic eff. | ||||
% | ||||
Electric eff. | ||||
% | ||||
Power | ||||
kW | hp |
*Absolute pressures. Use the default value (1.013 bar) for intakes at the atmosphere pressure.
Calculations from Metcalf and Eddy, Wastewater Engineering, 2003
Section geometry | |||
Bottom width | |||
mm | in | ||
Side slope base width¹ | |||
mm | in | ||
Internal diameter | |||
mm | in | ||
Water depth | |||
mm | in | ||
Slope of the channel² | |||
m/m or in/in | % | ||
Manning coefficient³ | |||
Kinematic viscosity | |||
m²/s | cSt | ||
Flow | |||
m³/h | gpm | ||
Average velocity | |||
m/s | ft/s | ||
Reynolds | |||
Froude | |||
Kinetic energy | |||
m | ft | ||
Specific energy | |||
m | ft | ||
Hydraulic radius | |||
mm | in | ||
Wetted perimeter | |||
mm | in |
¹ Base of the right-angle triangle with the water depth as height and the inclined side slope as hypotenuse. The solver considers both side slopes as identical.
² Inclination of the channel or the altitude loss per horizontal length.
³ Typical values from literature: 0.013 for concrete or cast iron, 0.03 for gravel and 0.01 for smooth plastic.
Pressure reading taps¹ | |||
Pipe internal diameter | |||
mm | in | ||
Orifice internal diameter | |||
mm | in | ||
Fluid density | |||
kg/m³ | lb/ft³ | ||
Dynamic viscosity (µ) | |||
Pa.s | cP | ||
Flow | |||
m³/h | gpm | ||
Discharge coefficient | |||
Pressure drop between taps | |||
bar | psi | ||
Overall headloss for the orifice plate | |||
m | ft |
Calculations from the ISO 5167 (2003) and from the ASME MFC-14M (2001) valid for incompressible fluids, sharp edged orifice plates; orifice diameter >=12.5mm, 1m >; pipe diameter > 25mm, 0.75 >; orifice diameter/pipe diameter > 0.1
¹ Tap type and distances from the orifice plate, upstream and downstream. D stands for the pipe internal diameter.
Standard throat width¹ | |||
Primary measurement head² (Ha) | |||
mm | in | ||
Secondary measurement head³ (Hb) | |||
mm | in | ||
Flow | |||
m³/h | gpm | ||
Submergence ratio | |||
¹ Standard sizes and discharge coefficients according to the ASTM D1941 (2013).
² Head measurement in the convergence section.
³ Head measurement in the throat section. Used only for submerged flow measurements, leave blank for free flow.
Free flow calculations according to the ASTM D1941 (2003). Submerged flow calculations according to the ISO 9826 (1992).
Measurement head¹ (h) | |||
mm | in | ||
Approach channel width (B) | |||
mm | in | ||
Throat width (b) | |||
mm | in | ||
Throat length (L) | |||
mm | in | ||
Bump height² (p) | |||
mm | in | ||
Flow | |||
m³/h | gpm |
Discharge coefficients and variable names according to the ISO 4359 (1983). Devices also known as Venturi flumes.
¹ According to the standard, the head is measured in the approach channel.
² Leave blank if the flume has a flat bottom (typical).
Balance | |||
Sum cations | meq/L | ||
Sum anions | meq/L | ||
Sum anions+silica+CO_{2} | meq/L | ||
Conductivity @ 25°C (if balanced) | µS/cm | ||
Total Dissolved Solids (TDS) | mg/L |
*For ion exchange purposes SiO_{2} is considered weakly ionized as H_{2}SiO_{3}(silicic acid). SiO_{2} has MW=60 and is removed as monovalent SiO_{2}^{-}.
Temperature | |||
°C | °F | ||
Dissolved CO_{2} | |||
mg/L CO_{2} | mg/L CaCO_{3} | ||
Conductivity and resistivity | |||
µS/cm | MΩ.cm | ||
pH | |||
Calculations from Truman S. Light, Elizabeth A. Kingman and Anthony C. Bevilacqua, Thornton Associates Inc, 1995, The Conductivity of low concentrations of CO2 dissolved in ultrapure water from 0-100°C
Chemical Oxygen Demand (COD) | ||
mg/L O_{2} | ||
Organic Matter as Permanganate | ||
mg/L KMnO_{4} | ||
Biological Oxygen Demand (BOD) | ||
mg/L O_{2} | ||
Total Organic Carbon (TOC) | ||
mg/L C |
Rough organic matter conversions based on the empiric factors from DuPont Water Resource Center for natural waters.
Temperature | ||||
°C | °F | |||
Calcium | ||||
mg/L CaCO_{3} | mg/L Ca | |||
Alkalinity | ||||
mg/L CaCO_{3} | mg/L HCO_{3} | |||
Total Dissolved Solids | ||||
mg/L | ||||
pH | ||||
LSI | ||||
Calculations from Edstrom Industries, 1998, Scale Forming Tendency of Water MI-4170.
Temperature | ||||
°C | °F | |||
Calcium | ||||
mg/L CaCO_{3} | mg/L Ca | |||
Alkalinity | ||||
mg/L CaCO_{3} | mg/L HCO_{3} | |||
Total Dissolved Solids | ||||
mg/L | ||||
pH | ||||
RSI | ||||
Temperature | ||||
°C | °F | |||
Pressure | ||||
bar | psi | |||
Active membrane diameter¹ | ||||
mm | in | |||
Membrane area | ||||
m² | ft² | |||
Average flow during cake formation² | ||||
L/h | gal/h | |||
Inverse of the average flow during cake formation² (Δt/ΔV) | ||||
s/L | s/gal | |||
Filtrate volume during cake formation² (ΔV) | ||||
L | gal | |||
MFI | ||||
s/L² |
Standard test conditions according to the ASTM D8002 (2015) for the MFI 0.45. The MFI will be normalized in case of different temperatures, areas or pressures from the standard test conditions.
¹ 47mm diameter membrane with 0.45µm mean pore size operating at 200±2KPa (2±0.02 bar). Active membrane diameter depends on the filter holder used.
² The cake formation is the linear segment of the (t/V) vs (V) graphic where t is the time in seconds and V is the filtrate volume in liters.
Water flow | ||||
m³/h | gpm | |||
Chemical dosage* | ||||
mg/L (ppm) | lb/ft³ | |||
Stock concentration | ||||
%_{w/w} | mg/L (ppm) | |||
Stock density | ||||
kg/m³ (g/L) | lb/ft³ | |||
Chemical flow - mass | ||||
kg/h | lb/h | |||
kg/day | lb/day | |||
Chemical flow - volume | ||||
L/h | gph | |||
L/day | gpd |
*Chemical dosage as if the product is at 100% concentration.
Chemical solution | ||
Temperature | |||
°C | °F | ||
Concentration | |||
%_{w/w} | mg/L (ppm) | ||
Density | |||
kg/m³ (g/L) | lb/ft³ | ||
Specific gravity | |||
Baumé density | |||
°B |
Properties interpolated from the tables provided by the chemical suppliers and from the Perry's Chemical Engineers Handbook.
Temperature | |||
°C | °F | ||
Density | |||
kg/m³ | lb/ft³ | ||
Dynamic Viscosity (µ) | |||
Pa.s | cP | ||
Kinematic Viscosity (v) | |||
m²/s | cSt | ||
pH | |||
Conductivity and resistivity | |||
µS/cm | MΩ.cm |
Properties at the atmospheric pressure (100 KPa) in the liquid form. Equations from R.C. Weast, 1983, CRC Handbook of Chemistry and Physics, 64th edition; from the David R. Maidment, 2003 Handbook of Hydrology, McGraw-Hill; from Truman S. Light, Elizabeth A. Kingman and Anthony C. Bevilacqua, Thornton Associates Inc, 1995, The Conductivity of low concentrations of CO2 dissolved in ultrapure water from 0-100°C; and from IAEA: Environmental Isotopes in the hydrological cycle: Principles and Applications Vol 1.
Stream 1 | |||
Flow^{1} | |||
% | |||
Concentration^{2} | |||
Stream 2 | |||
Flow^{1} | |||
% | |||
Concentration^{2} | |||
Stream 3 | |||
Flow^{1} | |||
% | |||
Concentration^{2} | |||
Result mixture | |||
Total flow | |||
Concentration |
^{1} Allows any unit of flow or volume (L/h, m³/h, gpm, m³, L, gal, etc...).
^{2} Allows any unit of concentration (mg/L, ppm, ppb, %, etc...) or temperatures.
Temperature | |||
°C | °F | ||
Density | |||
kg/m³ | lb/ft³ | ||
Specific gravity at 60°F (15.6°C) | |||
Baumé for liquids heavier than water | |||
°B | |||
Baumé for liquids lighter than water | |||
°B | |||
API gravity | |||
°API | |||
Brix¹ | |||
°Bx |
Equations from Perry's Chemical Engineers Handbook (8th Edition), 2008, McGraw-Hill and from the API Manual of Petroleum Measurement Standards Chapter 11, 2004.
¹ Brix will be calculated by the simplified formula. Specific gravity used on this solver was set to 15°C so it might be slighlty different from the standard at 20°C used in common Brix calculations.
Media volume | ||||
L | ft³ | |||
Water density | ||||
kg/m³ | lb/ft³ | |||
Stock concentration | ||||
%_{w/w} | mg/L (ppm) | |||
Stock density | ||||
kg/m³ (g/L) | lb/ft³ | |||
Regenerant dosage* | ||||
g/L_{resin} | lb/ft³_{resin} | |||
Diluted concentration | ||||
%_{w/w} | mg/L (ppm) | |||
Contact time | ||||
min | BV/h | |||
Stock regenerant | ||||
L | gal | |||
kg | lb | |||
L/h | gal/h | |||
Diluted regenerant | ||||
L | gal | |||
kg | lb | |||
L/h | gal/h | |||
Dilution water | ||||
L | gal | |||
L/h | gal/h |
*Chemical dosage per liter of resin at 100% concentration.
Gross flow | |||
m³/h | gpm | ||
Run length | |||
h | days | ||
Run volume | |||
m³ | gal | ||
Feed water Hardness | |||
mg/L CaCO_{3} | meq/L | ||
Feed water Sodium concentration | |||
mg/L | meq/L | ||
Design temperature | |||
°C | °F | ||
Desired safety factor¹ | |||
Regeneration level | |||
g/L_{resin} | |||
NaCl injection concentration | |||
% | |||
Resin type² | |||
Not defined |
|||
Resin volume | |||
L | ft³ | ||
Column internal diameter | |||
mm | in | ||
Column cylindrical height | |||
mm | in | ||
Resin height | |||
mm | in | ||
Pressure drop at design temperature | |||
bar | psi | ||
Final safety factor from column design¹ | |||
Contact time | |||
min | BV/h | ||
Hardness leakage | |||
mg/L CaCO_{3} | meq/L | ||
NaCl @ 100% for regeneration | |||
kg | lb | ||
Diluted NaCl volume for regeneration | |||
L | gal | ||
Water consumption for regeneration | |||
m³ | gal | ||
Overall regeneration duration | |||
min | h | ||
Regeneration step 1 - backwash³ | |||
m³/h | gpm | ||
min | h | ||
Regeneration step 2 - NaCl injection³ | |||
m³/h | gpm | ||
min | h | ||
Regeneration step 3 - displacement³ | |||
m³/h | gpm | ||
min | h | ||
Regeneration step 4 - fast rinse³ | |||
m³/h | gpm | ||
min | h |
Design based in the Ion Exchange resins engineering manuals.
¹ Safety factor over the calculated resin volume. The final safety factor might be higher because the solver rounds up the resin volume. Typical: 1.05 to 1.15.
² Suggested resins: Amberlite™ IRC120, Amberlite™ HPR1300, Amberlite™ HPR1200 or TapTec™ HCR-S.
³ Backwash in upflow direction. Operation, injection, displacement and rinse in downflow direction.
Average individual element recovery | ||||
% | ||||
Elements in series | ||||
Total system recovery | ||||
% |
Flux | ||||
LMH | GFD | |||
Net driving pressure | ||||
bar | psi | |||
Current temperature | ||||
°C | °F | |||
Reference temperature | ||||
°C | °F | |||
Water permeability¹ | ||||
LMH/bar | GFD/psi |
Valid for Microfiltration, Ultrafiltration and other porous membranes. Permeability is used for datasheet comparisons and real plant performance evaluation. Fouling decreases the permeability.
¹ If the "current temperature" is different than the "reference temperature", calculates the normalized permeability.
Test solution | |||
Solution concentration | |||
mg/L (ppm) | %_{w/w} | ||
Temperature | |||
°C | °F | ||
Feed pressure | |||
bar | psi | ||
Recovery | |||
% | |||
Element area | |||
m² | ft² | ||
Product flow | |||
m³/day | gpd | ||
Salt rejection | |||
% | |||
Water transport coefficient¹ at 25°C | |||
LMH/bar | GFD/psi | ||
Salt transport coefficient² at 25°C | |||
LMH | GFD |
The mass transport coefficients allow the datasheet comparison between Reverse Osmosis and some Nanofiltration membranes that were tested under different conditions or between new and used elements. This solver was calibrated for single element tests only. More information about the equations can be found here.
¹ Membrane flux per effective driven pressure (permeability) or A-value. Membranes with lower A coefficients will operate at higher pressures for the same permeate flow.
² Diffusion rate of the salt through the membrane or B-value. Elements with lower B coefficients have higher salt rejections. Note that each ionic compound has it's own B coefficient so you can't compare a membrane tested using NaCl with another using CaCl2.
Permeate flow | |||
m³/h | gpm | ||
Concentrate flow | |||
m³/h | gpm | ||
Recovery | |||
% | |||
Feed pressure | |||
bar | psi | ||
Concentrate pressure | |||
bar | psi | ||
Pressure drop¹ | |||
bar | psi | ||
Permeate pressure | |||
bar | psi | ||
Temperature | |||
°C | °F | ||
Total membrane area | |||
m² | ft² | ||
Feed dissolved solids | |||
µS/cm | mg/L | ||
Permeate dissolved solids | |||
µS/cm | mg/L | ||
Salt rejection | |||
% | |||
Water transport coefficient² at 25°C | |||
LMH/bar | GFD/psi | ||
Salt transport coefficient³ at 25°C | |||
LMH | GFD |
This solver was based in the ASTM D4516 (2010) but the normalized permeate flow is expressed as permeability and the normalized salt passage as a transport rate. This format allows the direct comparison between data from different plants. More information about the equations can be found here.
¹ Manufacturers recommend cleaning membranes after an increase of 10% of this value compared with the startup.
² Permeability or A-value. Proportional to the normalized permeate flow. RO manufacturers recommend cleaning membranes after decrease of 10% of this value compared with the startup.
³ Salt passage rate or B-value. Proportional to the normalized salt passage. Manufacturers recommend cleaning membranes after an increase of 10% of this value compared with the startup.
Product flow | |||
m³/h | gpm | ||
Recovery | |||
% | |||
Element area | |||
m² | ft² | ||
Target flux | |||
LMH | GFD | ||
Elements per vessel | |||
elements | |||
Pressure vessels per stage | |||
None |
|||
Flux from design | |||
LMH | GFD |
The result design may require adjustments in case of high temperatures, high recoveries or use of very low pressure membranes. Always validate the design using the membrane manufacturer projection software.
Media type¹ | |||
Filtration rate/velocity | |||
m/h | ft/h | ||
Media height | |||
mm | in | ||
Dynamic viscosity (µ) | |||
Pa.s | cP | ||
Fluid density | |||
kg/m³ | lb/ft³ | ||
Mean particle effective size | |||
mm | in | ||
Porosity | |||
% | |||
Ergun coefficients | |||
Kv | Ki | ||
Head loss | |||
m | in |
¹ Input values for particle sizes, porosity and Ergun coefficients.
Equations from MWH, 2005, Water Treatment Principles and Design 2nd edition.
Media type¹ | |||
Media height | |||
mm | in | ||
Desired expansion | |||
% | |||
Final height | |||
mm | in | ||
Dynamic viscosity (µ) | |||
Pa.s | cP | ||
Fluid density | |||
kg/m³ | lb/ft³ | ||
Particle density | |||
kg/m³ | lb/ft³ | ||
Mean particle effective size | |||
mm | in | ||
Settled bed porosity | |||
% | |||
Ergun coefficients | |||
Kv | Ki | ||
Backwash rate/velocity | |||
m/h | ft/h |
¹ Input values for particle sizes, porosity and Ergun coefficients.
Equations from MWH, 2005, Water Treatment Principles and Design 2nd edition based in the Akgiray and Saatçi, 2001 models.
Temperature | |||
°C | °F | ||
pH | |||
Total dissolved inorganic Carbon | |||
mg/L CaCO_{3} | |||
M-Alkalinity or Total ¹ | |||
mg/L CaCO_{3} | |||
P-Alkalinity ² | |||
mg/L CaCO_{3} | |||
Carbon Dioxide CO_{2} (gas) | |||
mg/L | mg/L CaCO_{3} | ||
Bicarbonate HCO_{3}^{-} | |||
mg/L | mg/L CaCO_{3} | ||
Carbonate CO_{3}^{2-} | |||
mg/L | mg/L CaCO_{3} |
¹ Total or M-Alkalinity refers to the Methyl-Orange indicator endpoint (pH 4.3).
² P-Alkalinity or Carbonate Alkalinity refers to the Phenolphthalein indicator endpoint (pH 8.3).
Calculations for pK_{1} from Harned and Davis, 1943 and for pK_{2} from Harned and Scholes, 1941.
Disinfectant | ||
Temperature | |||
°C | °F | ||
Log removal | |||
log | % | ||
CT | |||
min.mg/L | |||
Dosage* | |||
mg/L (ppm) | %_{w/w} | ||
Contact time* | |||
min | h |
CT stands for Concentration vs Time and is defined by the EPA Interim Enhanced Surface Water Treatment Rule (IESWTR). CT Values interpolated from the EPA Disinfection Profiling and Benchmarking Guidance Manual Appendix C, 1999. *Not required for the CT calculation.
pH | |||
Free Chlorine | |||
mg/L (ppm) | %_{w/w} | ||
Temperature | |||
°C | °F | ||
Log removal | |||
log | % | ||
CT | |||
min.mg/L | |||
Contact time | |||
min | h |
CT stands for Concentration vs Time and is defined by the EPA Interim Enhanced Surface Water Treatment Rule (IESWTR). CT Values calculated using the regression method according to the EPA Profiling and Benchmarking Guidance Manual Appendix E, 1999.
Oxidant | ||
Process flow | |||
m³/h | gpm | ||
Fe^{2+} concentration | |||
mg/L | |||
Oxidant dosage (as 100%)* | |||
mg/L | |||
kg/h | lb/h | ||
kg/day | lb/day | ||
Alkalinity consumed | |||
mg/L | |||
kg/h | lb/h | ||
kg/day | lb/day | ||
Dry sludge production | |||
kg/h | lb/h | ||
kg/day | lb/day |
*Stoichiometric values, no safety factors. Equations from ASCE/AWWA Water Treatment Plant Design, 3rd edition, 2003.
Oxidant | ||
Process flow | |||
m³/h | gpm | ||
Mn^{2+} concentration | |||
mg/L | |||
Oxidant dosage (as 100%)* | |||
mg/L | |||
kg/h | lb/h | ||
kg/day | lb/day | ||
Alkalinity consumed | |||
mg/L | |||
kg/h | lb/h | ||
kg/day | lb/day | ||
Dry sludge production | |||
kg/h | lb/h | ||
kg/day | lb/day |
*Stoichiometric values, no safety factors. Equations from ASCE/AWWA Water Treatment Plant Design, 3rd edition, 2003.
pH | |||
Total Nitrites | |||
mg/L NO_{2} | µmol/L | ||
Nitrous Acid HNO_{2} | |||
mg/L | µmol/L | ||
Nitrite ion NO_{2}^{-} | |||
mg/L | µmol/L |
Equilibrium constants at 25°C, pK=3.15.
pH correction chemical | ||
Temperature | |||
°C | °F | ||
Alkalinity¹ | |||
mg/L CaCO_{3} | meq/L | ||
Solution initial pH² | |||
Solution final pH | |||
Chemical dosage³ | |||
mg/L (ppm) | %_{w/w} |
Calculations based on Acids and Bases dissociation equilibrium. pK_{a} and pK_{b} constants from CRC Handbook of Chemistry and Physics, 84^{th} Edition (2004).
¹ Carbonates equilibrium for closed system - no CO_{2} exchange with the atmosphere.
² Set to 7 to find the pH of acid or base solutions in pure water.
³ Real dosage may be higher due chemical consumption by other contaminants. Negative values if the chemical needs to be neutralized to reach the pH.
Process flow | |||
m³/h | gpm | ||
Chemical dosage | |||
Aluminium Sulfate | mg/L | ||
Ferric Sulfate | mg/L | ||
Ferric Chloride | mg/L | ||
PAC | mg/L %Al | ||
Polymer | mg/L | ||
Turbidity removed | |||
NTU | |||
Dry sludge production* | |||
kg/h | lb/h | ||
kg/day | lb/day |
*Average values from real plant data. Equations from MWH, 2005, Water Treatment Principles and Design 2nd edition.
pH | |||
Total dissolved Silica | |||
mg/L SiO_{2} | µmol/L | ||
Ortho Silicic Acid Si(OH)_{4} | |||
mg/L | µmol/L | ||
Silicate ion Si(OH)_{3}^{-} | |||
mg/L | µmol/L |
Equilibrium constants at 25°C, pK=9.86.
pH | |||
Total Sulfates | |||
mg/L SO_{4} | µmol/L | ||
Hydrogen Sulfate HSO_{4}^{-} | |||
mg/L | µmol/L | ||
Sulfate SO_{4}^{-2} | |||
mg/L | µmol/L |
Equilibrium constants at 25°C, pK=1.99.
pH | |||
Total Sulfides | |||
mg/L H_{2}S | µmol/L | ||
Hydrogen Sulfide H_{2}S | |||
mg/L | µmol/L | ||
Bisulphide ion HS^{-} | |||
mg/L | µmol/L |
Equilibrium constants at 25°C, pK=7.02.
Plant flow | ||||
m³/h | gpm | |||
Waste sludge flow | ||||
m³/h | gpm | |||
Solids concentration in the reactor¹ | ||||
mg/L | lb/gal | |||
Solids returning from the clarifier² | ||||
mg/L | lb/gal | |||
Solids in the clarified/product water | ||||
mg/L | lb/gal | |||
Reactor volume | ||||
m³ | ft³ | |||
Solids retention time³ (SRT) | ||||
h | days |
¹ For activated sludges this can be the MLVSS (Mixed liquor volatile suspended solids) concentration in the aeration tank.
² Solids in the recirculation return to the reactor. For activated sludges this is the concentration in the return activated sludge (RAS) or the concentration in the waste sludge.
³ Also known as Mean Cell Residence Time (MCRT).
Clarifier influent flow | ||||
m³/h | gpm | |||
Solids influent concentration¹ | ||||
mg/L | lb/gal | |||
Clarifier cross-sectional area | ||||
m² | ft² | |||
Solids loading rate | ||||
kg/(m².h) | lb/(ft².h) |
¹ For activated sludges this can be the MLVSS (Mixed liquor volatile suspended solids) concentration from the aeration tank. For water treatment clarifiers this is usually the TSS.
Influent flow | ||||
m³/h | gpm | |||
Solids influent concentration¹ | ||||
mg/L | lb/gal | |||
Clarifier/reactor volume | ||||
m³ | ft³ | |||
Volumetric solids loading rate | ||||
kg/(m³.day) | lb/(ft³.day) |
¹ For activated sludges this can be the MLVSS (Mixed liquor volatile suspended solids) load in the clarifier or the BOD load in the aeration tank. For anaerobic reactors this is usually the COD load.
Plant flow | ||||
m³/h | gpm | |||
Recirculation sludge flow | ||||
m³/h | gpm | |||
Return activated sludge recycle ratio¹ | ||||
% | ||||
Solids concentration in the reactor² | ||||
mg/L | lb/gal | |||
Solids returning from the clarifier³ | ||||
mg/L | lb/gal |
¹ This ratio can be calculated either from the flows or from the solid concentrations.
² For activated sludges this can be the MLVSS (Mixed liquor volatile suspended solids) concentration in the aeration tank.
³ Solids in the recycle activated sludge (RAS) stream.
Influent flow | ||||
m³/h | gpm | |||
Influent suspended solids¹ | ||||
mg/L | lb/gal | |||
Suspended solids in the reactor² | ||||
mg/L | lb/gal | |||
Reactor volume³ | ||||
m³ | ft³ | |||
Sludge age | ||||
h | days |
¹ This can be either the VSS (volatile suspended solids) or the TSS (total suspended solids).
² This can be either the MLVSS (mixed liquor volatile suspended solids) or the MLSS (mixed liquor suspended solids). If using MLVSS, the inlet concentration must be VSS.
³ For activated sludges, the reactor is the aeration tank.
Interest rate | ||
% year | ||
% month | ||
% day |
Principal | ||||
Interest rate | ||||
% per period | ||||
Number of periods | ||||
Simple interest | ||||
Total value | ||||
Application | Plutocalc Water |
Error ID for system administrators | JSLoadError_EnginePCW |
Distribution | Unknown: engine not loaded |
Language | English |
Version | Unknown: engine not loaded |
Version details | release history |
Device details | Unknown: engine not loaded |
Contact | [email protected] |
Website | www.plutocalc.com |
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