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[Saidar]

Hey all,

I'm struggling with the following scenario:

I have a stoich reactor with reactions that are dependent on each other, for example:

A + B = C + D + E
F + C = G + H + A

As you can see the reactions produce reagents for each other. Thus the simulations needs to run both in parallel until equilibrium is reached (where nothing happens).

Another factor that influences this is the following global reaction:

H2O + HSO4- <--> H3O+ + SO4--

If a lot of H3O+ is used up in the reactor, the equilibrium should shift to the right to produce more H3O+.

The problem is the reactions within the stoich reactor is only calculated once in series (parallel also don't work), and the equilibrium shift is not taken into account. Thus I never get the pH out of the reactor to be higher than 2. It is supposed to be 6. A warning keeps popping up that not enough H3O+ is available, but the outlet streams contains a lot of H3O+ (due to the equilibrium being calculated afterwards).

Any idea how to setup the reactor to keep iterating until equilibrium is reached? I have tried splitting the stream 99% and recycling it but that did not work.

AN obvious solution is to put 10 reactors of the same configuration in series, but that is impractical and my simulation is very big so it is not going to work that good.

Any advice will be appreciated!

[Saidar]

Think I found a solution:

Add this reaction to the top of each acid consuming reactor:

H2O + HSO4- --> H3O+ + SO4--

Then there is enough acid for all reactions to take place. Afterwards equilibrium is established again by the global reaction:

H2O + HSO4- <--> H3O+ + SO4--