Abstract: A technique of controlling a steam generating boiler system includes using a rate of change of disturbance variables to control operation of a portion of the boiler system, and in particular, to control a temperature of output steam to a turbine. The technique uses a primary dynamic matrix control (DMC) block to control a field device that, at least in part, affects the output steam temperature. The primary DMC block uses the rate of change of a disturbance variable, a current output steam temperature, and an output steam temperature setpoint as inputs to generate a control signal. A derivative DMC block may be included to provide a boost signal based on the rate of change of the disturbance variable and/or other desired weighting. The boost signal is combined the control output of the primary DMC block to more quickly control the output steam temperature towards its desired level.

Abstract: A pressure and flow calculation technique that efficiently solves for pressures and flows within a process network uses both a simultaneous and a sequential solving method. The calculation technique first determines a flow conductance for each of the process network elements, linearizes pressure and flow relationships in each flow path by determining a linearized flow conductance for each process element and then determines a composite process network having a linearized, composite process component in each flow path to produce a simplified process network. A simultaneous solving method is then used to simultaneously solve for the pressures and flows at each of a set of junction nodes of the simplified process network and thereafter a sequential solving method is applied to determine the pressures and flows at the other nodes of the process network.

Abstract: Systems and methods for treating contaminated impound water are disclosed which include a pretreatment stage wherein contaminated water is oxidized, pH adjusted, treated with a coagulant, and treated with a polymer to form a flocculent comprising bulk solids and fine particles. The oxidizing step may include two or more stages, one of which is a treatment with ferrous iron generated from iron filings or steel wool. Bulk solids are removed, and the liquid portion containing fine particles is applied to a low pressure microfiltration unit to remove the fine particles resulting in a microfilter effluent. The microfilter effluent may be directly fed to a reverse osmosis (R/O) unit. The R/O reject may be recycled to another R/O unit (second pass). The R/O permeate may be blended as needed with the microfiltration effluent to provide the final discharge effluent with reduced contaminant levels and maximized throughput.

Abstract: A technique of controlling a steam generating boiler system using dynamic matrix control includes preventing saturated steam from entering a superheater section. A dynamic matrix control block uses a rate of change of a disturbance variable, a current output steam temperature, and an output steam setpoint as inputs to generate a control signal. A prevention block modifies the control signal based on a saturated steam temperature and an intermediate steam temperature. In some embodiments, the control signal is modified based on a threshold and/or an adjustable function g(x). The modified control signal is used to control a field device that, at least in part, affects the intermediate steam and output steam of the boiler system. In some embodiments, the prevention block is included in the dynamic matrix control block.

Abstract: Embodiments of methods and systems for controlling a load generated by a power generating system may include controlling at least a portion of the system using model-based control techniques. The model-based control techniques may include a dynamic matrix controller (DMC) that receives a load demand and a process variable as inputs and generates a control signal based on the inputs and a stored model. The model may be configured based on parametric testing, and may be modifiable. Other inputs may also be used to determine the control signal. In an embodiment, a turbine is controlled by a first DMC and a boiler is controlled by a second DMC, and the control signals generated by the first and the second DMCs are used in conjunction to control the generated load. Techniques to move the power generating system from Proportional-Integral-Derivative based control to model-based control are also disclosed.

Abstract: A water conditioning composition includes water; at least one gluconate compound; at least one carbonate compound; a non-ionic preservative; and a phosphate buffer. For example, the composition can include 87-95 wt. % water; 0.5 to 1.5 wt. % gluconate compound; 3 to 8 wt. % carbonate compound; 0.5 to 1.5 wt. % non-ionic preservative; and 0.5 to 2.5 wt. % phosphate buffer.

Abstract: A pressure and flow calculation technique can be used in a distributed process network simulation system that uses the sequential solving method to perform better or faster simulations of a process flow, especially with respect to process junction nodes at which flow either converges or diverges. The pressure and flow variable determination technique uses a grouped node identification technique that identifies a local set of nodes for each junction node of the process network to use when solving for the pressure at the junction node, a grouped node iteration technique that uses the grouped set of nodes at each junction node to perform iterative pressure calculations at the junction node, and a flow-based pressure calibration technique at each junction node to enable the system to perform highly accurate pressure and flow variable determination at each junction node in real-time.

Abstract: A technique of controlling a steam generating boiler system having multiple superheater sections includes determining multiple control signals to control a temperature of output steam to a turbine. The technique uses a first control block to determine an offset value based on multiple input temperatures and a dynamic matrix control (DMC) block to determine input steam control signals based on an output temperature and an output temperature setpoint. The technique modifies one of the input steam control signals based on the offset value. The modified input steam control signal and the unmodified input steam control signal are provided to respective field devices to control the input temperatures and, as a result, the output temperature.

Abstract: Methods of treating animal litter and/or bedding material for control of volatile ammonia and soluble phosphorous include applying granular partially hydrated ferric sulfate to the litter. The partially hydrated ferric sulfate ranges from gray to tan in color and is spread onto the litter at a rate effective to reduce ammonia volatilization and reduce soluble phosphorous. Relative to reagent grade ferric sulfate, the partially hydrated ferric sulfate exhibits lower hygroscopicity and higher deliquescence. The ferric sulfate is prepared by a process comprising oxidizing ferrous sulfate with sulfuric acid using a molecular oxygen oxidizing agent at an elevated pressure relative to atmospheric and at a temperature of 60° C. to 140° C. to produce a gray to tan colored granular product.

Abstract: A shower filter between a downwardly slanting shower arm and a shower head, including a base, and a vertical housing with filler material. The base has an input chamber for receiving water from the shower arm, and an output chamber from which water may be discharged to the shower head. The housing is secured at its bottom end to the base and has a first port communicating with the base input chamber and a second port communicating with the base output chamber. A tube carries water from the housing first port to the top end of the housing, where it is diffused before passing down through the filter material and second port to the output chamber. A fragrant block is mounted to the base.

Abstract: A process for improving the yield and efficiency of an ethanol fermentation plant that receives organic fermentable feedstock material, prepares the feedstock for fermentation, ferments the feedstock with yeast to produce ethanol, and produces stillage as a byproduct of ethanol fermentation. The process steps which can be operated independently or in combination, may include, but are not limited to, degrading fatty acids in the fermentable feedstock material prior to fermentation; degrading cellulose and hemicellulose present in the feedstock prior to fermentation; adding a surfactant to the fermentable feedstock; separating a liquid fraction from the stillage; recycling the liquid fraction to be combined with the fermentable feedstock; recovering a solid fraction from the stillage; and introducing at least a portion of the solid fraction to an anaerobic digester to produce methane.

Abstract: An energy management system uses an expert engine and a numerical solver to determine an optimal manner of using and controlling the various energy consumption, producing and storage equipment in a plant/community. The energy management system operates the various energy manufacturing and energy usage components of the plant to minimize the cost of energy over time, or at various different times, while still meeting certain constraints or requirements within the operational system, such as producing a certain amount of heat or cooling, a certain power level, a certain level of production, etc. In some cases, the energy management system may cause the operational equipment of the plant to produce unneeded energy that can be stored until a later time and then used, or that can be sold back to a public utility, for example, so as to reduce the overall cost of energy within the plant.

Abstract: A fitting for connecting a hose to ports of a water filter bypass valve, the hose having an inner diameter less than that of the ports. The fitting includes a unitary base member, a second end connector, and first and second washers. The base member includes a first end connector securable to either of the ports, a neck having a truncated cone shaped inner wall, and a second end having a first outer diameter with a disk shaped flange extending outwardly to a second outer diameter greater than the first outer diameter. The second end connector has a radially inwardly extending flange disposed around the base member second end with and inner diameter greater than the first outer diameter and less than the second outer diameter of the base member second end. The first and second washers are in the first and second end connectors, respectively.

Abstract: A process characteristic parameter determination system uses a process model and a tuning module to accurately determine a value for a process characteristic parameter within a plant without measuring the process characteristic parameter directly, and may operate on-line or while the process is running to automatically determine a correct value of the process characteristic parameter at any time during on-going operation of the process. The process characteristic parameter value, which may be a heat transfer coefficient value for a heat exchanger, can then be used to enable the determination of a more accurate simulation result and/or to make other on-line process decisions, such as process control decisions, process operational mode decisions, process maintenance decisions such as implementing a soot blowing operation, etc.

Abstract: Water treatment systems and methods. Embodiments provide water treatment systems which comprise first oxidation, particulate filtration, and membrane filtration subsystems in that order. Systems also comprise recirculation paths and sensors for these subsystems. A controller determines whether to recirculate water to a previous subsystem in the order. Systems can comprise downstream second oxidation, high pressure membrane, ion exchange, activated carbon subsystems and/or ultraviolet contactors. Systems with high pressure membranes can comprise a pump before the high pressure membranes, a booster pump of the high pressure membrane subsystem, and a damping tank. In such systems the controller maintains a pressure in the damping tank. High pressure membrane subsystems can further comprise nanofiltration membranes and RO membranes. Systems can comprise bypass paths for some/all of the subsystems. For such systems, the controller further determines, whether to bypass these subsystems.

Abstract: Systems and methods for treating contaminated impound water are disclosed which include a pretreatment stage wherein contaminated water is oxidized, pH adjusted, treated with a coagulant, and treated with a polymer to form a flocculent comprising bulk solids and fine particles. The oxidizing step may include two or more stages, one of which is a treatment with ferrous iron generated from iron filings or steel wool. Bulk solids are removed, and the liquid portion containing fine particles is applied to a low pressure microfiltration unit to remove the fine particles resulting in a microfilter effluent. The microfilter effluent may be directly fed to a reverse osmosis (R/O) unit. The R/O reject may be recycled to another R/O unit (second pass). The R/O permeate may be blended as needed with the microfiltration effluent to provide the final discharge effluent with reduced contaminant levels and maximized throughput.

Abstract: Methods and apparatus to compensate first principle-based simulation models are disclosed. An example method to compensate a first-principle based simulation model includes applying one or more first test inputs to a process system to generate first output data, applying one or more second test inputs to a first principle model to generate second output data, generating an error model based on the first and second output data, applying input data to the first principle model to generate simulation model output data, and compensating the model data via the error model to generate compensated model output data.

Abstract: A process control system simulation technique performs real-time simulation of an actual process control network as that network is running within a process plant in a manner that is synchronized with the operation of the actual process control network. This real-time, synchronized simulation system includes a simulation process control network and a process model which are automatically updated periodically during the operation of the actual process control network to reflect changes made to the process control network, as well as to account for changes in the plant itself, i.e., changes which require an updated process model. The simulation system provides for more readily accessible and usable simulation activities, as the process control network and the process models used within the simulation system are synchronized with and up-to-date with respect to the current process operating conditions.