Space Time Formula:
From: | To: |
Definition: Space time is the time required to process one reactor volume of feed based on entrance conditions for a first-order reaction in mixed flow.
Purpose: It helps chemical engineers determine the residence time needed for a given reaction conversion in a continuously stirred tank reactor (CSTR).
The calculator uses the formula:
Where:
Explanation: The formula relates the space time to the reaction rate constant and the fractional conversion of reactant.
Details: Proper space time calculation ensures optimal reactor design, efficient reaction conversion, and cost-effective operation.
Tips: Enter the rate constant (must be > 0), initial reactant concentration, and current reactant concentration. All values must be positive.
Q1: What is the difference between space time and residence time?
A: Space time is based on inlet conditions, while residence time is the actual time fluid elements spend in the reactor.
Q2: How does space time affect conversion?
A: Higher space time generally leads to higher conversion, but the relationship depends on reaction kinetics.
Q3: What are typical units for the rate constant?
A: For first-order reactions, the rate constant has units of 1/s (reciprocal seconds).
Q4: Can this calculator be used for batch reactors?
A: No, this formula is specifically for continuous mixed flow reactors (CSTRs).
Q5: What if my reactant concentration is zero?
A: The formula becomes undefined when C=0, which corresponds to 100% conversion (infinite space time theoretically required).