Methods and devices for controlling polymerization reactions using the controlled addition of oxygen to a reactor. The method may include providing a reactor comprising one or more chemical components suitable for facilitating a polymerization reaction and continuously measuring one or more polymer characteristics of polymers generated by the polymerization reaction in the reactor. The method may also include determining, using a control algorithm, based on the continuous measurements of one or more polymer characteristics, the amount of oxygen to add to the reactor at one or more time points during the polymerization reaction in order to cause the one or more polymer characteristics to follow a predetermined target trajectory.

Assemblies and methods to enhance control of a fluid catalytic cracking (FCC) processing assembly associated with a refining operation, may include supplying a hydrocarbon feedstock to one or more first processing units associated with the refining operation. The assemblies and methods also may include conditioning a hydrocarbon feedstock and unit material samples, and analyzing the samples via one or more spectroscopic analyzers. The assemblies and methods further may include prescriptively controlling, via one or more FCC process controllers based at least in part on the hydrocarbon feedstock properties and the unit material properties, the FCC processing assembly, so that the prescriptively controlling results in enhancing accuracy of target content of materials produced by the FCC processing assembly, thereby to more responsively control the FCC processing assembly to achieve material outputs that more accurately and responsively converge on target properties.

A foam sensor device is used for monitoring foam within a vessel. The sensor (e.g. accelerometer) is encapsulated inside a water-tight, sterilizable, shell, which floats on a liquid contained. In one example, the foam sensor device includes an accelerometer for detecting and measuring rotation and movement of the foam sensor device and generates movement data based on the detected movement. During a learning or calibration process, sensor data (e.g., movement data) from the foam sensor device is analyzed and classified using machine learning and/or signal processing methods to extract features indicative of different possible foam statuses, including varying levels of foam, or no foam and generate models for the different statuses. During normal operation, the foam sensor device transmits sensor data to an analyzer containing the pre-calibrated models, which determines whether there is foam or not. Based on the foam status, a pump controller adds anti-foam solution.