CJ
ChemJunction
Chemical Engineering • Design Suite

Process Engineering Calculators

Professional engineering tools with unit system selection (SI vs Imperial) and rigorous thermal design equations.

REACTOR THERMAL SUITE

Reactor Heating & Cooling Operations

Rigorous thermal design calculations incorporating actual process design equations (Non-Isothermal & Isothermal Operations).

Select Unit System for Calculations:
1. Heating Time using Hot Water (Non-Isothermal Heating Medium)
Exact Equation & Description (from Process Design Data):

K factor: K = exp(U * A / (W * Cw))

Energy balance integration: ln((T1 - t1) / (T1 - t2)) = (W * Cw / (M * Cm)) * ((K - 1) / K) * t

Time reqd (t): t = [ ln((T1 - t1) / (T1 - t2)) * (M * Cm) / (W * Cw) ] * [ K / (K - 1) ]
Description: Rigorous transient heating equation accounting for the finite heat capacity and flow rate of the heating fluid.

2. Heating Time using Steam (Isothermal Heating Medium)
Exact Equation & Description (from Process Design Data):

Energy balance integration: ln((T1 - t1) / (T1 - t2)) = (U * A * t) / (M * Cm)

Time reqd (t): t = [ ln((T1 - t1) / (T1 - t2)) * (M * Cm) ] / (U * A)
Description: Rigorous isothermal heating equation assuming constant jacket temperature (e.g. condensing steam).

3. Cooling Time using Non-Isothermal Cooling Medium
Exact Equation & Description (from Process Design Data):

K factor: K = exp(U * A / (W * Cw))

Energy balance integration: ln((T1 - t1) / (T2 - t1)) = (W * Cw / (M * Cm)) * ((K - 1) / K) * t

Time reqd (t): t = [ ln((T1 - t1) / (T2 - t1)) * (M * Cm) / (W * Cw) ] * [ K / (K - 1) ]
Description: Rigorous transient cooling equation accounting for the finite heat capacity and flow rate of the cooling fluid.

4. Heating Time using External Heat Exchanger & Non-Isothermal Medium
Exact Equation & Description (from Process Design Data):

K3 factor: K3 = exp(U * A * (1 / (W * C) - 1 / (w * c)))

Energy balance integration: ln((T1 - t1) / (T1 - t2)) = (w * W * C / (K3 * w * cp - W * C)) * ((K3 - 1) / M) * t

Time reqd (t): t = [ ln((T1 - t1) / (T1 - t2)) * (K3 * w * cp - W * C) * M ] / [ w * W * C * (K3 - 1) ]
Description: Rigorous transient heating equation for external heat exchanger with recirculation batch flow and non-isothermal heating fluid.

5. Heating Time using External Heat Exchanger & Isothermal Medium
Exact Equation & Description (from Process Design Data):

K2 factor: K2 = exp(U * A / (w * c))

Energy balance integration: ln((T1 - t1) / (T1 - t2)) = (w * c / (M * c)) * ((K2 - 1) / K2) * t

Time reqd (t): t = [ ln((T1 - t1) / (T1 - t2)) * M ] / [ w * ((K2 - 1) / K2) ]
Description: Rigorous isothermal heating equation for external heat exchanger with recirculation batch flow and constant steam temperature.

6. Cooling Time using External Heat Exchanger & Non-Isothermal Medium
Exact Equation & Description (from Process Design Data):

K4 factor: K4 = exp(U * A * (1 / (W * C) - 1 / (w * c)))

Energy balance integration: ln((T1 - t1) / (T2 - t1)) = (W * C / (K4 * w * c - W * C)) * ((K4 - 1) / M) * t

Time reqd (t): t = [ ln((T1 - t1) / (T2 - t1)) * M * (K4 * w * c - W * C) * C ] / [ W * C * w * c * (K4 - 1) ]
Description: Rigorous transient cooling equation for external heat exchanger with recirculation batch flow and non-isothermal cooling medium.

7. Cooling Time using External Heat Exchanger & Isothermal Medium
Exact Equation & Description (from Process Design Data):

K1 factor: K1 = exp(U * A / (W * C))

Energy balance integration: ln((T1 - t1) / (T2 - t1)) = (W / M) * ((K1 - 1) / K1) * t

Time reqd (t): t = [ ln((T1 - t1) / (T2 - t1)) * M ] / [ W * ((K1 - 1) / K1) ]
Description: Rigorous isothermal cooling equation for external heat exchanger with recirculation batch flow and constant cooling fluid temperature.