Mass Balance Calculator

Solve steady-state mass and component balances around a separation unit. Calculate product/waste flow rates, component recovery, split ratio, and yield.

Inputs

Feed rate (kg/hr)

Feed concentration (wt%)

Product concentration (wt%)

Waste concentration (wt%)

Tab to move between fields

Results

Product flow rate (kg/hr)

301.08

Waste flow rate (kg/hr)

698.92

Component recovery (%)

95.34

Component in feed (kg/hr)300

Component in product (kg/hr)286.02

Split ratio (P/F)0.3

Mass yield (%)30.11

Balance closure error (kg/hr)0

Component Error0

How to Use This Calculator

Enter Feed rate (kg/hr), Feed concentration (wt%), and Product concentration (wt%).
Set Waste concentration (wt%).
Review Product flow rate (kg/hr), Waste flow rate (kg/hr), and Component recovery (%).
Use Component in feed (kg/hr) and Component in product (kg/hr) to inform your decision.

How the result changes with Feed concentration (wt%)

Feed concentration (wt%)	Product flow rate (kg/hr)	Waste flow rate (kg/hr)	Component recovery (%)
10	86.02	913.98	81.72
35	354.84	645.16	96.31
65	677.42	322.58	99.01
90	946.24	53.76	99.88

What each input means

Feed rate (kg/hr): Total mass flow rate of the feed stream.
Feed concentration (wt%): Weight percent of the key component in the feed.
Product concentration (wt%): Desired weight percent of key component in the product stream.
Waste concentration (wt%): Weight percent of key component remaining in the waste/reject stream.

What each result means

Product flow rate (kg/hr): Mass flow rate of the product stream, solved from the component balance.
Waste flow rate (kg/hr): Mass flow rate of the waste/reject stream.
Component in feed (kg/hr): Mass flow of the key component entering in the feed.
Component in product (kg/hr): Mass flow of the key component leaving in the product.
Component recovery (%): Percentage of the key component captured in the product stream.
Split ratio (P/F): Fraction of feed mass that becomes product.
Mass yield (%): Product mass as a percentage of feed mass.
Balance closure error (kg/hr): Should be ~0 if the balance is correctly solved.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Feed rate (kg/hr) = 1000, Feed concentration (wt%) = 30, Product concentration (wt%) = 95, Waste concentration (wt%) = 2 = 4 input(s) provided
Calculate Product flow rate
Product flow rate
301.08 = 301.08
Calculate Waste flow rate
Waste flow rate
698.92 = 698.92
Calculate Component recovery
Component recovery = feedComponentFlow > 0
95.34 = 95.34
Calculate Component in feed
Component in feed = feedRate * xF
300 = 300
Calculate Component in product
Component in product = productRate * xP
286.02 = 286.02

Engine last updated July 26, 2026. Checked against 3 independently-derived tests — how we verify calculators.

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