Free Software for Chemical Process Simulation?

chthonicdaemon asks: "I am about to embark on a mission: to create a Free (as in freedom) chemical process simulator. My field is control engineering, and as such, dynamic simulation is what it is all about. There is an open source steady-state simulator called sim42, but I have not found one that can do dynamics. There is also a lot of work available in the form of implementation standards, so I am confident that it can be done. Is there anything like this out there that I have not found, and what open technology could I leverage to get this done faster (perhaps something like SML)."