1. What is Percent Excess Oxygen?

Definition: Percent Excess Oxygen is the amount of oxygen in the incoming air not used during combustion and is related to percentage excess air.

Purpose: It helps in combustion analysis to determine the efficiency of the combustion process and ensure proper air-fuel ratios.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \% \text{ Excess } O_2 \) — Percentage of excess oxygen
• \( M_{\text{Fed}} \) — Moles of air fed to the process (moles)
• \( M_{\text{OxyTheo}} \) — Theoretical moles of oxygen required (moles)
• 0.21 — Fraction of oxygen in air

Explanation: The formula calculates what percentage of oxygen in the incoming air exceeds what's theoretically needed for complete combustion.

3. Importance of Percent Excess Oxygen Calculation

Details: Proper calculation ensures efficient combustion, minimizes fuel waste, and helps control emissions in industrial processes.

4. Using the Calculator

Tips: Enter the total moles of air fed to the process and the theoretical moles of oxygen required. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is 0.21 used in the formula?
A: 0.21 represents the mole fraction of oxygen in air (21% oxygen by volume in atmospheric air).

Q2: What's a typical percent excess oxygen range?
A: Most combustion systems operate with 2-10% excess oxygen for efficiency and safety.

Q3: How is this related to percent excess air?
A: Percent excess oxygen is directly proportional to percent excess air, since oxygen content in air is constant.

Q4: What if I get negative values?
A: Negative values indicate insufficient air for complete combustion (oxygen-deficient conditions).

Q5: How do I find theoretical oxygen requirements?
A: Theoretical oxygen is calculated from stoichiometric equations of the combustion reactions.