Patent Document ID: 7985812
Application ID: 12734406
Patent Flag: 1

Claim One:
1. A method for controlling a solution process for the catalytic polymerisation of olefins in which one or more monomers are polymerised in a reactor to form a (co)polymer which is soluble in a solvent present in the reactor, said process comprising recycling unreacted monomers and solvent and feeding fresh monomers and solvent in said reactor, the method comprising: a) measuring the values of a set of operating parameters, including: (i) temperature (T) of the polymerisation reactor; (ii) pressure (P) of the polymerisation reactor; (iii) density (ρ) of the solution within the polymerisation reactor; (iv) flow rate of the recycle stream; (v) concentration of monomers in the recycle stream; (vi) concentration of solvent in the recycle stream; (vii) flow rate of the fresh monomers fed to the polymerisation reactor; b) calculating a set of predicted parameters related to the stream discharged from the polymerisation reactor using the values of the operating parameters, the predicted parameters comprising: (i) flow rate of unreacted monomers; (ii) flow rate of discharged solvent; (iii) flow rate of discharged polymer; c) comparing said values of said predicted parameters to target parameters defined for optimum operation of the process to produce a polymer with desired characteristics and properties; d) detecting possible deviations of the value of said predicted parameters from the values of the corresponding target parameters; e) optionally adjusting the flow rate of one or more of said monomers freshly fed to said polymerisation reactor, and/or of any other component of the fresh feed or recycle fed to said reactor, and/or adjusting the temperature (T) and/or the pressure (P) of said polymerisation reactor to compensate for said possible deviations; wherein said calculation of said predicted parameters is carried out by an algorithm performing calculation of the extent of reaction (ξ) as a function of the solution density (ρ) and then calculating the whole composition of the solution, said calculation comprising resolution of a system of equations comprising the equation of state, equations for the relative incorporation of monomers into the (co)polymer, stoichiometric equations and transformation equations.