One
of R2 Controls specialties is pH control. Many years ago at the Foxboro
company, customers would complain that their Foxboro (analog) controllers would
not control correctly on pH loops. After verifying the controller hardware
and adjustments were OK, we would investigate the bad behavior of the control
loop. The solution to pH control problems involves understanding the
chemistry, chemical engineering, and control system engineering. While
there are many special things that can be done with the control system to make
improvements, we discovered that many of the most effective solutions involved
making process changes. pH probe location, mixer specifications, and
mixing vessel design, and control valve sizing and piping are typically critical
to the success of the control loop. Over the years many special techniques
were developed for feedforward control, non-linear feedback controllers
(hyperlink to Tech tips), control valve sequencing, and control logic to handle
either batch or continuous processes. Equally important was the
development of design know-how to determine for example when to use a batch
process, how to utilize inline mixers, and sizing tanks & mixers to achieve
specific control targets like EPA limits of pH 6.0 to 9.0 effluents.
In many cases pH control is a dependent objective, as in the case of BIO reactor
where culture growth is highly dependent on the right pH or in a Clarifier where
precipitation depends on solubility which in turn depends on pH.
Key Benefits
All the benefits of a large E&C firm at a fraction of the cost
Engineer the project to work the first time
Reduced Reagent consumption
Reliable, maintainable operation
Minimize Capital Expenditures to achieve the desired result
Capabilities
R2
Controls can really handle the whole project from process design, fabrication,
wiring, and commissioning. This includes project scheduling, project
management, construction supervision, sampling and preparation of titration
curves, vessel & mixer fabrication, control panel design, valve selection
and sizing, reagent procurement recommendations, lime, alkali, and acid reagent
deliver systems, instrumentation selection, control system design, controller
configuration, tuning and commissioning, digital recorder configuration,
alarming, display, interlocks, reporting, integration to SCADA and other systems
via serial links, Ethernet, or other connections.
Send mail to rys@R2Controls.com with
questions or comments about this web site.
Last modified: 18 August 2023
One
of R2 Controls specialties is pH control. Many years ago at the Foxboro
company, customers would complain that their Foxboro (analog) controllers would
not control correctly on pH loops. After verifying the controller hardware
and adjustments were OK, we would investigate the bad behavior of the control
loop. The solution to pH control problems involves understanding the
chemistry, chemical engineering, and control system engineering. While
there are many special things that can be done with the control system to make
improvements, we discovered that many of the most effective solutions involved
making process changes. pH probe location, mixer specifications, and
mixing vessel design, and control valve sizing and piping are typically critical
to the success of the control loop. Over the years many special techniques
were developed for feedforward control, non-linear feedback controllers
(hyperlink to Tech tips), control valve sequencing, and control logic to handle
either batch or continuous processes. Equally important was the
development of design know-how to determine for example when to use a batch
process, how to utilize inline mixers, and sizing tanks & mixers to achieve
specific control targets like EPA limits of pH 6.0 to 9.0 effluents.
In many cases pH control is a dependent objective, as in the case of BIO reactor
where culture growth is highly dependent on the right pH or in a Clarifier where
precipitation depends on solubility which in turn depends on pH.
R2
Controls can really handle the whole project from process design, fabrication,
wiring, and commissioning. This includes project scheduling, project
management, construction supervision, sampling and preparation of titration
curves, vessel & mixer fabrication, control panel design, valve selection
and sizing, reagent procurement recommendations, lime, alkali, and acid reagent
deliver systems, instrumentation selection, control system design, controller
configuration, tuning and commissioning, digital recorder configuration,
alarming, display, interlocks, reporting, integration to SCADA and other systems
via serial links, Ethernet, or other connections.