Patent application number | Description | Published |
20100130704 | Methods and Systems for Controlling Polymer Particle Size - Techniques are provided for producing polymer particles of a size just slightly larger than the size of polymer fines. The technique may prevent or limit the occurrence of reactor fouls associated with large polymer particles. The technique also may provide a greater weight percentage of solids in the reactor. The desired polymer particle size may be achieved by employing a catalyst having particles of a size determined based on the expected catalyst productivity. In certain embodiments, the catalyst particle size may be determined based on the expected catalyst productivity, the polymer particle density, the catalyst particle density, and/or the polymer particle size. | 05-27-2010 |
20120022692 | PREDICTION AND CONTROL SOLUTION FOR POLYMERIZATION REACTOR OPERATION - Techniques and systems for the prevention of reactor fouls in polymerization reactors are described. Described embodiments include techniques and systems for performing analyses on reactor data collected over time for the detection of incipient reactor fouling. Techniques are provided for monitoring the state of the reactor as well as for monitoring individual system parameters, including rates of change, for predicting the onset of a reactor foul. In particular, the techniques may be implemented such that predictive proactive control systems may be integrated into polymerization reactor systems to prevent reactor fouling. | 01-26-2012 |
20120070345 | METHODS AND SYSTEMS FOR CONTROLLING POLYMER PARTICLE SIZE - Techniques are provided for producing polymer particles of a size just slightly larger than the size of polymer fines. The technique may prevent or limit the occurrence of reactor fouls associated with large polymer particles. The technique also may provide a greater weight percentage of solids in the reactor. The desired polymer particle size may be achieved by employing a catalyst having particles of a size determined based on the expected catalyst productivity. In certain embodiments, the catalyst particle size may be determined based on the expected catalyst productivity, the polymer particle density, the catalyst particle density, and/or the polymer particle size. | 03-22-2012 |
20120283395 | CATALYST FEED CONTROL DURING CATALYST TRANSITION PERIODS - Techniques are provided for operating a reactor during a catalyst transition period. The instantaneous reaction rate during a catalyst transition period can be determined using real-time measured process variables, and material balance calculations to provide an instantaneous reaction rate in approximately real time. According to certain embodiments, a material balance can be performed on the reactor system using a continuous ideal stirred tank reactor to determine the fractions of each type of catalyst that are present in the reactor, as well as the overall weight percent of catalyst in the reactor. A controller can then calculate the overall instantaneous reaction rate based on the respective catalyst fractions and the overall weight percent of catalyst in the reactor. The catalyst feed rate can then be adjusted based on the determined instantaneous reaction rate to maintain the instantaneous reaction rate within desired limits during a catalyst transition period. | 11-08-2012 |
20130137836 | Methods for Removing Polymer Skins from Reactor Walls - Methods for removing polymer skins or build-up from reactor walls in polymerization reactor systems containing a loop slurry reactor are disclosed. Such methods can employ removing some or all of the comonomer from the reactor system in combination with increasing the polymerization temperature of the loop slurry reactor. | 05-30-2013 |
20140363340 | CATALYST FEED CONTROL DURING CATALYST TRANSITION PERIODS - Techniques are provided for operating a reactor during a catalyst transition period. The instantaneous reaction rate during a catalyst transition period can be determined using real-time measured process variables, and material balance calculations to provide an instantaneous reaction rate in approximately real time. According to certain embodiments, a material balance can be performed on the reactor system using a continuous ideal stirred tank reactor to determine the fractions of each type of catalyst that are present in the reactor, as well as the overall weight percent of catalyst in the reactor. A controller can then calculate the overall instantaneous reaction rate based on the respective catalyst fractions and the overall weight percent of catalyst in the reactor. The catalyst feed rate can then be adjusted based on the determined instantaneous reaction rate to maintain the instantaneous reaction rate within desired limits during a catalyst transition period. | 12-11-2014 |
20150175719 | POLYOLEFIN REACTOR SYSTEM HAVING A GAS PHASE REACTOR - A system and method for polymerizing olefin in a gas phase reactor into a polyolefin in presence of catalyst, measuring static charge in the reactor system; determining an indication of polyolefin fines in the reactor system, and adjusting operation of the reactor system in response to the indication. | 06-25-2015 |
20150175721 | POLYOLEFIN REACTOR SYSTEM HAVING A GAS PHASE REACTOR AND SOLIDS RECOVERY - A system and method for a gas phase reactor to polymerize olefin into a polyolefin, and for a solids recovery system to separate solids from overhead gas discharged from the gas phase reactor and to return the solids to the gas phase reactor. A control system may perform a fluid flow calculation of the solids recovery system. The solids recovery system may employ a vertical motive device and/or horizontal motive device. | 06-25-2015 |