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In an embodiment, a polymerization process comprises circulating, with a pump, a reaction mixture slurry in a polymerization loop reactor during a polymerization process, detecting a pressure change in the reaction mixture slurry downstream of the pump, generating, by a pressure controller, a takeof

In an embodiment, a polymerization process comprises circulating, with a pump, a reaction mixture slurry in a polymerization loop reactor during a polymerization process, detecting a pressure change in the reaction mixture slurry downstream of the pump, generating, by a pressure controller, a takeoff valve actuation signal for a takeoff valve based on the pressure change, generating, by the pressure controller, a correction to the takeoff valve actuation signal, generating, by the pressure controller, a time delay for the correction, applying the correction to the takeoff valve actuation signal to generate a corrected takeoff valve actuation signal, providing the corrected takeoff valve actuation signal to the takeoff valve after the time delay, and adjusting a position of the takeoff valve in response to providing the corrected takeoff valve actuation signal. The reactor pressure is based on the takeoff valve position.

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1. A polymerization process comprising: circulating, with a pump, a reaction mixture slurry in a polymerization loop reactor during a polymerization process, wherein the reaction mixture slurry comprises an olefin, a catalyst, and polymer particles;detecting a pressure change in the reaction mixture

1. A polymerization process comprising: circulating, with a pump, a reaction mixture slurry in a polymerization loop reactor during a polymerization process, wherein the reaction mixture slurry comprises an olefin, a catalyst, and polymer particles;detecting a pressure change in the reaction mixture slurry downstream of the pump;generating, by a pressure controller, a takeoff valve actuation signal for a takeoff valve based on the pressure change, wherein a portion of the reaction mixture slurry is continually removed from the polymerization reactor in proportion to the takeoff valve position, and wherein the reaction mixture slurry is retained in the polymerization reactor when the takeoff valve is in a closed position, wherein the reactor pressure is based on the takeoff valve position;generating, by the pressure controller, a correction to the takeoff valve actuation signal;generating, by the pressure controller, a time delay for the correction;applying the correction to the takeoff valve actuation signal to generate a corrected takeoff valve actuation signal;providing the corrected takeoff valve actuation signal to the takeoff valve after the time delay; andadjusting a position of the takeoff valve in response to providing the corrected takeoff valve actuation signal. 2. The polymerization process of claim 1, wherein the pressure change is a pressure increase of the reaction mixture slurry, and wherein the takeoff valve actuation signal causes the takeoff valve to move towards the open position in response to the pressure increase, and wherein the correction reduces an amount to which the takeoff valve moves towards the open position. 3. The polymerization process of claim 1, wherein the pressure change is a pressure decrease of the reaction mixture slurry, and wherein the takeoff valve actuation signal causes the takeoff valve to move towards the closed position in response to the pressure increase, and wherein the correction reduces an amount to which the takeoff valve moves towards the closed position. 4. The polymerization process of claim 1, wherein the time delay is based on a time for the reaction mixture to flow from the pump to the takeoff valve in the polymerization reactor. 5. The polymerization process of claim 1, wherein a magnitude of the correction is based on a change in a pump power of the pump relative to a time average of the pump power, wherein the time average of the pump power is an average pump power over a time corresponding to between 1 and 10 circulation periods of the reaction mixture slurry through the polymerization loop reactor. 6. The polymerization process of claim 1, wherein applying the correction reduces a pump power fluctuation of the pump compared to adjusting the position of the takeoff valve using the takeoff valve actuation signal without applying the correction. 7. The polymerization process of claim 1, wherein the correction is between about 0.1% and about 1% of a signal range of the takeoff valve actuation signal. 8. The polymerization process of claim 7, further comprising applying a tuning factor between about 1% and about 50% to the correction prior to applying the correction to the takeoff valve actuation signal. 9. The polymerization process of claim 1, wherein the pump is at least one of an axial flow pump, a mix flow pump, or a radial flow pump. 10. The polymerization process of claim 1, wherein a concentration of the polymer particles in the reaction mixture slurry is greater than about 40 wt %. 11. The polymerization process of claim 10, wherein the concentration of the polymer particles in an outlet line downstream of the takeoff valve is greater than an average polymer particle concentration of the reaction mixture. 12. A polymerization process comprising: circulating a reaction mixture slurry in a polymerization loop reactor during a polymerization process; wherein the reaction mixture slurry comprises an olefin, a catalyst, and a polymer product, and wherein the polymerization loop reactor comprises a pump, wherein the pump is disposed in-line in the polymerization loop reactor, wherein a pressure sensor is disposed downstream of the pump, wherein a first takeoff valve is disposed downstream of the pump, and wherein a second takeoff valve is disposed downstream of the first takeoff valve;detecting a pressure change in the reaction mixture slurry at the pressure sensor;generating, by a pressure controller in signal communication with the pressure sensor, a first takeoff valve actuation signal for the first takeoff valve and a second takeoff valve actuation signal for the second takeoff valve based on the pressure change;generating, by the pressure controller, a first correction to the first takeoff valve actuation signal;generating, by the pressure controller, a first time delay for the first correction, wherein the first time delay is based on a distance between the first takeoff control valve and the pump;applying the first correction to the first takeoff valve actuation signal after the first time delay to generate a first corrected takeoff valve actuation signal;generating, by the pressure controller, a second correction to the second takeoff valve actuation signal;generating, by the pressure controller, a second time delay for the second correction, wherein the second time delay is based on a distance between the second takeoff control valve and the pump;applying the second correction to the second takeoff valve actuation signal after the second time delay to generate a second corrected takeoff valve actuation signal; andadjusting a position of the first takeoff valve and the second takeoff valve during the polymerization process in response to the first corrected takeoff valve actuation signal and the second corrected takeoff valve actuation signal, respectively. 13. The polymerization process of claim 12, further comprising: removing a portion of the reaction mixture slurry from the polymerization loop reactor via the first takeoff valve, the second takeoff valve, or both, wherein a portion of the reaction mixture slurry is removed from the polymerization reactor when the first takeoff valve, the second takeoff valve, or both are in an open position, and wherein the reaction mixture slurry is retained in the polymerization reactor when the first takeoff valve, the second takeoff valve, or both are in a closed position, and wherein adjusting the position of the first takeoff valve, the second takeoff valve, or both comprises moving the first takeoff valve, the second takeoff valve, or both towards the open position; andchanging the concentration of polymer particles downstream of the first takeoff valve, the second takeoff valve, or both in response to moving the first takeoff valve, the second takeoff valve, or both towards the open position. 14. The polymerization process of claim 13, further comprising: generating a pressure reduction at the first pressure sensor or the second pressure sensor in response to changing the concentration of polymer particles of the reaction mixture downstream of the takeoff valve. 15. The polymerization process of claim 12, wherein a magnitude of the first or second corrections is based on a change in a pump power of the pump. 16. The polymerization process of claim 12, wherein the first or second corrections comprise a portion of a signal range of the takeoff valve actuation signal. 17. The polymerization process of claim 16, wherein the first or second corrections are limited to between about 0.1% and about 1% of the signal range of the takeoff valve actuation signal. 18. A method of controlling a polymerization process, the method comprising: circulating a reaction mixture slurry in a polymerization reactor during a polymerization process, wherein the reaction mixture slurry comprises an olefin, a catalyst, and a polymer product;detecting, by sensor, at least one condition within the polymerization reactor during the polymerization process;detecting, by a pump power sensor, a pumping power fluctuation of at least one pump used in the circulating of the reaction mixture slurry;developing, by a processor, a probability network;transferring the at least one condition and the pumping power fluctuation to the probability network;determining, by the processor, the probability that the at least one condition is a cause of the pumping power fluctuation;determining that the probability that the at least one condition is a cause of the pumping power fluctuation is above a threshold;controlling the at least one condition when the probability that the at least one condition is a cause of the pumping power fluctuation is above a threshold; andreducing the pumping power fluctuation in response to controlling the at least one condition. 19. The method of claim 18, wherein the probability network is a Bayesian network. 20. The method of claim 18, wherein the at least one condition comprises a pressure change of the reaction mixture slurry downstream of the at least one pump, and wherein controlling the at least one condition comprises: generating, by the processor, a takeoff valve actuation signal for a takeoff valve based on the pressure change;generating, by the processor, a correction to the takeoff valve actuation signal;applying the correction to the takeoff valve actuation signal to generate a corrected takeoff valve actuation signal; andadjusting a position of the takeoff valve in response to the corrected takeoff valve actuation signal. 21. The method of claim 20, wherein controlling the at least one condition further comprises: generating, by the processor, a time delay for the correction, wherein applying the correction comprises applying the correction to the takeoff valve actuation signal after the time delay. 22. The method of claim 21, wherein the time delay is based on a time for the reaction mixture slurry to travel from the takeoff control valve to the at least one pump. 23. The method of claim 21, wherein the correction is between about 0.1% and about 1% of a signal range of the takeoff valve actuation signal. 24. The method of claim 23, further comprising applying a tuning factor between about 1% and about 50% to the correction prior to applying the correction to the takeoff valve actuation signal. 25. The method of claim 18, wherein the at least one condition comprises one or more of: a concentration of the olefin in the reaction mixture slurry, a concentration of the catalyst in the reaction mixture slurry, a concentration of an alpha olefin reaction product in the reaction mixture slurry, a composition of the catalyst, a composition of the olefin, a composition of the alpha olefin reaction product, a density of the reaction mixture slurry, a composition of the diluent, a pressure within the polymerization reactor, an average temperature of the reaction mixture slurry, a flowrate of the reaction mixture, a temperature of a coolant inlet in a heat transfer portion of the polymerization reactor, or any combination thereof. 26. The method of claim 18, wherein the polymerization reactor is a loop slurry reactor, a continuous stirred tank reactor, or a plug flow reactor.