AnythingOnline / Free calculators and utilities

Agriculture & Environment calculators

Choose a task below. Check each calculator’s assumptions and units before using its result.

Activated Sludge F to M Calculator - Aeration MCRT Sizing

Determine Food-to-Microorganism (F/M) ratio, Mean Cell Residence Time (MCRT sludge age), hydraulic detention time, and aeration basin volatile solids inventory.

Activated Sludge F/M Ratio Calculator - Aeration MLVSS

Balance organic food substrate (BOD5) against biological mixed liquor volatile biomass (MLVSS) and determine hydraulic retention time (HRT).

Anaerobic Digester Biogas Calculator - Methane Yield Sizing

Determine daily biogas production (SCFD), pure methane energy yield, volatile solids destruction (VSD), and CHP cogenerated electric power in kW.

API 421 Oil Water Separator Calculator - Sizing Area Flow

Size gravity oil-water separators per API Publication 421: calculate droplet rise velocity, chamber cross-sectional area, required plan surface area, and chamber dimensions.

Baghouse Air to Cloth Calculator - Filter Area Sizing

Determine required filter media cloth area, total bag count, operating Air-to-Cloth (A/C) ratio, and interstitial can velocity per ACGIH guidelines.

Bucket Elevator Capacity Calculator - BPH & Motor HP

Determine volumetric handling capacity in bushels per hour (BPH), metric tons/hour, belt speed in FPM, and required head shaft drive motor horsepower.

Chlorine Disinfection CT Calculator - Contact Time Sizing

Determine EPA Surface Water Treatment Rule (SWTR) CT compliance, T10 effective contact detention time, baffling factors, and log-inactivation of pathogens.

Clarifier Overflow Rate Calculator - Surface & Weir Loading

Determine surface overflow rate (SOR), peripheral V-notch weir loading rate (WLR), hydraulic detention time, and solids loading rate (SLR) for sedimentation clarifiers.

Cyclone Dust Collector Calculator - Lapple Cut Point Sizing

Calculate cyclone cut-point diameter (d50), fractional particulate collection efficiency, gas inlet velocity, and static pressure drop per Lapple and Stairmand models.

DAF Air to Solids Ratio Calculator - Flotation Efficiency

Size DAF recycle pressurization systems and calculate the Air-to-Solids (A/S) ratio, microscopic bubble air release, and hydraulic loading rates.

Diffused Aeration Oxygen Calculator - SOTR AOTR Sizing

Convert Actual Oxygen Transfer Rate (AOTR) to Standard Oxygen Transfer Rate (SOTR) per ASCE 2-06 and calculate required blower airflow in SCFM and motor horsepower.

Dust Conveying Velocity Calculator - Duct Transport Sizing

Determine ACGIH minimum particulate transport velocities, duct branch diameters, velocity pressures, and friction static pressure losses for dust collection systems.

Flare Knockout Drum Calculator - API 521 Droplet Sizing

Size horizontal flare knockout (KO) drums per API 521: calculate critical droplet settling velocity (300 - 600 µm), allowable vapor velocity, vessel diameter, and emergency liquid holdup.

Flare Purge Gas Rate Calculator - Husa Ingress Velocity

Calculate continuous purge gas flow rates (SCFH) and velocity to prevent atmospheric oxygen ingress and internal burnback explosions per API 521 and the Husa correlation.

Flare Stack Height Calculator - API 521 Radiation

Calculate minimum required flare stack height, thermal radiation contours at grade, flame length, and wind tilt angles per API Standard 521.

Flare Tip Velocity Calculator - API 521 Mach Number

Calculate flare tip exit velocity, Mach number, and regulatory compliance limits per API 521 and EPA 40 CFR 60.18 to ensure flame stability and prevent blow-off.

Gas Turbine Water Injection Calculator - NOx Diluent Rate

Calculate demineralized water or steam injection flow rates (GPM & lb/hr), water-to-fuel mass ratios, thermal NOx suppression (ppmvd), and power augmentation boost.

Grain Aeration Fan CFM Calculator - Static Pressure inWG

Determine total fan airflow delivery (CFM), system resistance static pressure in inches water gauge (inWG) from Shedd's curves, and motor horsepower.

Grain Auger Capacity Calculator - BPH Throughput & Angle

Calculate portable screw conveyor throughput in bushels per hour (BPH), angle-of-incline derating, flight rotational RPM, and drive PTO horsepower.

Grain Drying Shrink Calculator - Moisture Loss & Bushels

Calculate exact physical water loss, commercial elevator handling shrink deductions, net delivered bushels, and drying fuel expenses.

Grain Silo Capacity Calculator - Bushels & Metric Tons

Determine total grain storage capacity in Winchester bushels, metric tons, and cubic feet, accounting for conical roof peaking and deep-bin pack compaction.

Greenhouse Heater Calculator - BTU Loss & Glazing

Calculate total BTU/hr heating requirements based on surface area, glazing U-value, and winter design temperatures.

Ion Exchange Softener Calculator - Resin Volume Sizing

Size industrial Strong Acid Cation (SAC) water softener resin beds, calculate total hardness grains removed, salt regenerant consumption, and cycle service runtimes.

Lamella Clarifier Calculator - Inclined Plate Settler

Calculate total effective horizontal settling area, footprint space reduction percentage, plate pack hydraulic loading, and Reynolds flow stability for lamella plate clarifiers.

Lawn Fertilizer Calculator - Nitrogen Rate & Bag Pounds

Determine exact fertilizer bag weight to apply 0.5 to 1.0 lb of nitrogen per 1,000 square feet.

Mixed Bed Polisher Calculator - Silica Breakthrough Life

Calculate mixed-bed demineralizer polisher service run time to reactive silica breakthrough (<10 ppb), Strong Base Anion (SBA) resin capacity, and chemical regenerant demand.

Mulch Coverage Calculator - Cubic Yards & Bag Count

Determine exact cubic yards, cubic feet, and bagged mulch quantities for garden beds.

Plant Spacing Calculator - Grid Rows & Square Footage

Calculate total plant counts for square and staggered triangular groundcover patterns.

Pulse Jet Baghouse Air Calculator - Pulse Cleaning Sizing

Determine continuous compressed air consumption (SCFM), air receiver tank sizing, pulse valve air volume per shot, and required air compressor motor horsepower.

Raised Bed Soil Calculator - Cubic Feet, Yards & Mix

Calculate total cubic feet, cubic yards, and component blend ratios for garden raised beds.

Reverse Osmosis NDP Calculator - Osmotic Pressure Sizing

Calculate feed-concentrate average osmotic pressure, Net Driving Pressure (NDP), temperature correction factor (TCF), and normalized permeate flux per ASTM D4516.

Silt Density Index Calculator - ASTM D4189 SDI Sizing

Calculate ASTM D4189 Silt Density Index (SDI15, SDI10, SDI5) from filtration times, percent plugging, and reverse osmosis membrane colloidal fouling risk.

Sludge Dewatering Polymer Calculator - Belt Press Sizing

Determine polymer conditioning dosage (lbs/dry ton), dewatered cake production (wet tons/day), filtrate capture efficiency, and operational chemical operating costs.

Sludge Thickener Sizing Calculator - Gravity Flux Solids

Size municipal and industrial gravity sludge thickeners: calculate required tank surface area, circular diameter, solids flux loading (lb/ft²·day), and thickened underflow volume.

Sludge Volume Index SVI Calculator - Settleability & MLSS

Compute SVI in mL/g from 30-minute settleometer jar tests and mixed liquor suspended solids (MLSS), diagnose filamentous bulking, and estimate RAS density.

Thermal Oxidizer Calculator - Residence Time Destruction

Size industrial direct-fired thermal oxidizers (DFTO) for 99%+ VOC destruction: calculate chamber volume, high-temperature residence time, auxiliary fuel duty, and flue gas flow.

Ultrafiltration Flux Calculator - TMP Membrane Sizing

Calculate ultrafiltration Transmembrane Pressure (TMP), operating permeate flux (LMH & GFD), 20°C temperature-normalized permeability, and backwash triggers.

Wastewater Chlorine CT Calculator - Dosage & Disinfection

Determine chlorine feed rate in lbs/day and gallons/day, contact chamber detention time, chlorine demand, and regulatory CT values for pathogen inactivation.

Wet Scrubber NTU Calculator - Packing Depth Sizing

Determine Number of Transfer Units (NTU), packed bed depth (Z), liquid-to-gas ratio (L/G), and pressure drop for chemical packed tower absorption scrubbers.