Assumptions:

All the units and ducting are well isolated, meaning adiabatic.

Because there is adequate agitation inside the process unit, the average temperatures and compositions are well represented.

When sulfuric acid is highly diluted, the mixture's density may be thought to be reasonably near to that of pure water.

As stated in point $3$ above, concentrated sulfuric acid's density cannot be reduced to a simple form.

Since the pachucas need different quantities of the leach liquor, $($stream $10)$ the product stream, should be viewed as a disturbance rather than a stable stream.

Throughout the process unit's constrained working ranges, the properties of the related materials are treated as constants.

Steam doesn't go through a phase shift while exchanging heat with the contents of the tank; it just loses temperature.

Derive an energy balance for the tank