| 摘要 |
In a batch process control system employing storage tanks without mixers, properties of the storage tank pump out feedstock may be modeled to more accurately control the quality of a process. This model may not require the measurement of input or pump out flow or assume perfect blending. Rather, the developed model may assume that feedstock input into a storage tank may remain layered with some mixing due to continuous convection, turbulence during loading, or other factors. The model may include a projection of the properties describing a storage tank layer of input material into the model. For each new load of storage tank input feedstock, model zones may be shifted and the zone from which the feedstock is drawn may be updated with the properties from the new load. |
| 主权项 |
1. A computer-implemented method for determining feedstock material properties in a mixer-less storage tank of a process control plant, the method comprising:
receiving, from a sensor disposed within the process control plant, a measured process variable associated with at least one of a feedstock or the mixer-less storage tank; applying, by a processor-implemented function block, feedstock property values of a previous feedstock zone to a new feedstock zone; establishing, by the processor-implemented function block, a pump out zone based on a storage tank level measurement relative to a tank outlet; calculating, by the processor-implemented function block, average feedstock property values for a total amount of feedstock within the storage tank; calculating, by the processor-implemented function block, a mixing factor for the pump out zone; calculating, by the processor-implemented function block, pump out feedstock property values for the pump out zone based on the average feedstock property values and the mixing factor; applying, by the processor-implemented function block, the pump out feedstock property values to the pump out zone of the storage tank to determine feedstock material properties of the pump out feedstock leaving the mixer-less storage tank; determining, by the processor-implemented function block, a process correction based upon the determined feedstock material properties of the pump out feedstock, wherein the process correction indicates an adjustment to one or more aspects of the operation of the process control plant; and causing, by the processor-implemented function block, the process correction to be implemented within the process control plant to adjust the operation of the one or more aspects of the process control plant; wherein the feedstock in the pump out zone is partially mixed with other feedstock in the storage tank, and wherein at least one of the storage tank level measurement, the average feedstock property values, or the mixing factor is based at least in part upon the received measured process variable. |
