Greg's Response:

Dynamic simulations running faster than real time are key to ensuring the best column temperature controller tuning. Except for high purity

Russ' Response:

Test means to review the model predictions (output values) with both data and logical expectations.  If your model outputs adequately match the process data and expectations over a wide range of operating conditions, then you

Greg's Response:

Dynamic simulations running faster than real time are key to ensuring the best column temperature control strategy. The manipulation of separ

Russ' Response:

Here are eight steps in developing a dynamic model. Details and examples can be accessed under the Modeling/Simulation menu on my web site, www.r3eda.com.

1. Inventory - Decide the inventory that
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Greg's Response:

Dynamic simulations can be help ensure distillation column pressure does not cause instability from operation at the weep point or flood point. The opera

Russ' Response:

Earlier I shared that I typically classify models as empirical or phenomenological.

In phenomenological models, the mathematical functions are grounded in a mechanistic relation. These models could be termed rigoro

Greg's Response:

Batch-operated stirred cooling crystallizers are the most common type in the industry, but they tend to yield poor quality, primarily due to the high cooling

Russ' Response:

I would broadly classify models as empirical or phenomenological.  

Empirical models are developed by matching flexible mathematical functions to data.  The functions might be neural networks, or classic statistical power

Greg's Response:

The basic loop arrangement for dryer temperature control would use cascade control of outlet temperature to set inlet temperature. However, a constant outlet temper

Julie's Response:

Many years ago, one site had an incident where an interruption in the flow of an organic fuel led to a deflagration. As a result, the operators always r

Russ' Response:

I would broadly classify models as empirical or phenomenological.

Empirical models are developed by matching flexible mathematical functions to data.  The functions migh

Greg's Response:

In kilns and calciners, there are typically four zones. First is a drying zone of constant temperature, followed by a heating zone of rising temperature

Julie's Response:

Back in 2019, the new DuPont was formed after the merger and split with Dow. Many sites were struggling to continue their migration proje

Greg's Response:

A vessel is defined here as storage, recycle, blend, or surge volume where there is no heat of reaction and no agitator. Fortunately, most vessel volumes are so la

Greg's Response:

Flows much lower than design causes a high process gain and high process deadtime that can lead to temperature oscillations and possible instability. Low v

Russ' Response:

Traditionally, process design uses steady state (SS) simulation, and it serves its purpose well.  Most analysis of processes and textbook instruction on how processes work use SS r

Greg's Response:

Temperature RTD sensors should use 4 wires and TC sensors should use extension wires of same material as sensor with length as short as possible to minim

Greg's Response:

Temperature is often the most important of the common measurements because it is an indicator of process stream composition and product quality. Temperature

Greg's Response:

Lime feeders have a transportation delay that is proportional to the length of the feeder divided by its speed. This transportation delay may be several min

Greg's Response:

A common misconception is that the slope of the titration curve and, therefore, the system sensitivity can be decreased by reagent dilution. Reagent di

Greg's Response:

If the reagent pipeline is partially filled or empty or a dip tube is backfilled with process fluid, the regent delivery delay becomes the biggest sour

Greg's Response:

For a reagent dose to be precise enough, the reagent’s logarithmic acid dissociation constant (pKa) should be close to the pH set point so that it tends to f

Greg's Response:

Stick and slip generally occur together and have a common cause of friction in the actuator design, stem packing, and seating surfaces. Rotary valves with

Greg's Response:

Static mixer have noisy pH measurements. Signal filtering can help but a downstream volume is needed to provide smoothing of pH oscillations that can be large