Air Classifier (Altun): Difference between revisions

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== Description ==
== Description ==


This article describes the '''Altun and Benzer''' (2014) model for air classification.{{Altun and Benzer (2014)}}
This article describes the '''Altun and Benzer''' (2014) model for high efficiency air classifiers.{{Altun and Benzer (2014)}}
 
High efficiency air classifiers may be alternatively described as ''dynamic'' or ''third generation'' air classifiers.


== Model theory ==
== Model theory ==


{{Under construction|section}}
The Altun air classifier model applies the [[Partition (Size, Whiten-Beta)|Whiten-Beta efficiency curve]] to partition particles to the overflow stream:
 
{{Model theory (Text, Whiten-Beta Efficiency Curve)}}
 
Additional relations link terms of the efficiency curve equation with operating parameters.
 
=== Corrected cut size ===
 
The corrected cut size, <math>d_{50 \rm c}</math> (mm), is:
 
:<math>d_{50 \rm c} = k_{d_{50 \rm c}} \left ( \dfrac{\mathit{AF}}{ 3600 . \mathit{RS}.F} \right )^{n_{d_{50 \rm c}}}</math>
 
where:
* <math>\mathit{AF}</math> is the classifier air flow rate (m<sup>3</sup>/h)
* <math>\mathit{RS}</math> is the rotor speed of the classifier (m/s)
* <math>F</math> is the flow rate of -36+3 µm size particles in the feed (t/h)
* <math>k_{d_{50 \rm c}}</math> and <math>n_{d_{50 \rm c}}</math> are the coefficient and exponent, respectively, of the cut size equation.
 
=== Sharpness of separation ===
 
The sharpness of separation term, <math>\alpha</math>, is estimated by:
 
:<math>\alpha = k_{\alpha} \left ( \dfrac{D}{\mathit{DL}} \right )^{n_{\alpha}}</math>
 
where:
* <math>D</math> is the classifier chamber diameter (m)
* <math>\mathit{DL}</math> is the dust loading of the classifier feed (kg/m<sup>3</sup>)
* <math>k_{\alpha}</math> and <math>n_{\alpha}</math> are the coefficient and exponent, respectively, of the sharpness of separation equation.
 
The dust loading, <math>\mathit{DL}</math> (kg/m<sup>3</sup>), is calculated from the feed and air flow rates:
 
:<math>\mathit{DL} = \dfrac{ 1000 . (Q_{\rm M,F})_{\rm S}}{\mathit{AF}}</math>
 
where <math>(Q_{\rm M,F})_{\rm S}</math> is the mass flow rate of solids in the feed (t/h)
 
=== Fines bypass ===
 
The fraction of the finest particles reporting to overflow, <math>C</math> (frac), is:
 
:<math>C = \dfrac{100 - k_C (\mathit{DL})^{n_C}}{100}</math>
 
where <math>k_C</math> and <math>n_C</math> are the coefficient and exponent, respectively, of the fines bypass equation.
 
=== Fish-hook parameter ===
 
The parameter controlling the initial rise of the efficiency curve in fines sizes (fish-hook), <math>\beta</math>, is:
 
:<math>\beta = k_{\beta} \mathit{DL}^{n_{\beta}} - c_{\beta}</math>
 
where <math>k_{\beta}</math>, <math>n_{\beta}</math> and <math>c_{\beta}</math> are the coefficient, exponent and constant, respectively, of the fish-hook equation.
 
Altun and Benzer (2014) also provide an equation for the <math>\beta^*</math> term of the efficiency equation. However, Whiten's definition of <math>\beta^*</math> requires its value to be computed in complement to the specified value of <math>\beta</math> in the efficiency equation (see [[Partition (Size, Whiten-Beta)]] for more information).
 
Therefore, the <math>\beta^*</math> equation is excluded from this implementation of Altun and Benzer's (2014) air classifier model.
 
=== Equation parameters ===
 
Altun and Benzer's (2014) test work was conducted on a range of Sepol, Sepax and Sepmaster industrial scale dynamic air classifiers. The parameter values in Table 1 were derived by regression analyses of their industrial sampling results.
 
:{| class="wikitable"
|+ Table 1. Air classifier model equation parameters (after Altun and Benzer, 2014).{{Altun and Benzer (2014)}}
|-
! Equation !! Coefficient, <math>k</math> !! Exponent, <math>n</math> !! Constant, <math>c</math>
|-
| <math>\alpha</math> || 0.905 || 1.2679 || -
|-
| <math>d_{50 \rm c}</math> || 0.4048 || 0.7775 || -
|-
| <math>C</math> || 10.467 || 1.4171 || -
|-
| <math>\beta</math> || 0.4417 || 1.4171 || 0.1293
|}
 
This implementation of the air classifier model allows a user to specify the values of the equation coefficients, exponents and constants directly. Altun and Benzer's (2014) values may be used, or new values derived from specific industrial or laboratory test work programmes.
 
=== Multi-component modelling ===
 
Altun and co-workers have published subsequent journal articles outlining similar model treatments for multi-component feeds, where particle density differences and agglomeration are observed to affect classification performance.{{Altun et al. (2016)}}{{Altun (2022)}}
 
However, this work was only conducted on laboratory scale equipment rather than operating industrial air classifiers. Additional non-standard material measurements are also required (e.g. fluidity index). As such, these model implementations are not included here.
 
=== Partition metrics ===
 
{{Model theory (Text, Hydrocyclone, Partition Metrics)}}


== Excel ==
== Excel ==
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The Altun air classifier model may be invoked from the Excel formula bar with the following function call:
The Altun air classifier model may be invoked from the Excel formula bar with the following function call:


<syntaxhighlight lang="vb">=mdUnit_AirClassifier_Altun(Parameters as Range, Size as Range, Feed as Range, OreSG Range)</syntaxhighlight>
<syntaxhighlight lang="vb">=mdUnit_AirClassifier_Altun(Parameters as Range, Size as Range, Feed as Range)</syntaxhighlight>


{{Excel (Text, Help, No Arguments)}}
{{Excel (Text, Help, No Arguments)}}
Line 22: Line 107:
\begin{bmatrix}
\begin{bmatrix}
D\text{ (m)}\\
D\text{ (m)}\\
{\rm AF}\text{ (m}^3\text{/h)}\\
\mathit{AF}\text{ (m}^3\text{/h)}\\
{\rm RS}\text{ (m/s)}\\
\mathit{RS}\text{ (m/s)}\\
k_{\alpha}\\
k_{\alpha}\\
n_{\alpha}\\
n_{\alpha}\\
Line 45: Line 130:
(Q_{\rm M,F})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,F})_{1m}\text{ (t/h)}\\  
(Q_{\rm M,F})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,F})_{1m}\text{ (t/h)}\\  
\vdots & \ddots & \vdots\\  
\vdots & \ddots & \vdots\\  
(Q_{\rm M,F})_{n1}\text{ (t/h)} & \dots & (Q_{\rm M,F})_{nm}\text{ (t/h)}\\  
(Q_{\rm M,F})_{p1}\text{ (t/h)} & \dots & (Q_{\rm M,F})_{pm}\text{ (t/h)}\\  
\end{bmatrix},\;\;\;\;\;\;
\end{bmatrix},\;\;\;\;\;\;
OreSG= \begin{bmatrix}
(\rho_{\rm S})_{1}\text{ (t/m}^\text{3}\text{)} & \dots & (\rho_{\rm S})_m\text{ (t/m}^\text{3}\text{)}\\
\end{bmatrix}


</math>
</math>


where:
where:
* <math>D</math> is the classifier chamber diameter (m)
* <math>{\rm AF}</math> is the air flow rate  (m<sup>3</sup>/h)
* <math>{\rm RS}</math> is rotor speed (m/s)
* <math>k</math> is an equation coefficient
* <math>n</math> is an equation exponent
* <math>c</math> is an equation constant
* <math>(Q_{\rm M,F})_{\rm L}</math> is the mass flow rate of liquids in the feed (t/h)'
* <math>p</math> is the number of size intervals
* <math>p</math> is the number of size intervals
* <math>m</math> is the number of ore types
* <math>m</math> is the number of ore types
* <math>d_i</math> is the size of the square mesh interval that mass is retained on (mm)
* <math>d_i</math> is the size of the square mesh interval that mass is retained on (mm)
* <math>d_{i+1}<d_i<d_{i-1}</math>, i.e. descending size order from top size (<math>d_{1}</math>) to sub mesh (<math>d_{p}=0</math> mm)
* <math>d_{i+1}<d_i<d_{i-1}</math>, i.e. descending size order from top size (<math>d_{1}</math>) to sub mesh (<math>d_{p}=0</math> mm)
* <math>\rho_{\rm S}</math> is the density of solids (t/m<sup>3</sup>)
* <math>(Q_{\rm M,F})_{\rm L}</math> is the mass flow rate of liquids in the feed (t/h)


=== Results ===
=== Results ===
Line 77: Line 151:


\begin{bmatrix}
\begin{bmatrix}
{\rm DL}\text{ (kg/m}^3\text{)}\\
\mathit{DL}\text{ (kg/m}^3\text{)}\\
F\text{ (t/h)}\\
F\text{ (t/h)}\\
\alpha\\
\alpha\\
Line 86: Line 160:
(Q_{\rm M,OF})_{\rm L}\text{ (t/h)}\\
(Q_{\rm M,OF})_{\rm L}\text{ (t/h)}\\
(Q_{\rm M,UF})_{\rm L}\text{ (t/h)}\\
(Q_{\rm M,UF})_{\rm L}\text{ (t/h)}\\
d_{50}\text{ (mm)}\\
E_{\rm p}\text{ (mm)}\\
I\\
\end{bmatrix}
\end{bmatrix}


Line 94: Line 171:
\bar d_1\text{ (mm)}\\
\bar d_1\text{ (mm)}\\
\vdots\\
\vdots\\
\bar d_n\text{ (mm)}
\bar d_p\text{ (mm)}
\end{bmatrix}
\end{bmatrix}


Line 103: Line 180:
(Q_{\rm M,UF})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,UF})_{1m}\text{ (t/h)}\\
(Q_{\rm M,UF})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,UF})_{1m}\text{ (t/h)}\\
\vdots & \ddots & \vdots\\
\vdots & \ddots & \vdots\\
(Q_{\rm M,UF})_{n1}\text{ (t/h)} & \dots & (Q_{\rm M,UF})_{nm}\text{ (t/h)}\\
(Q_{\rm M,UF})_{p1}\text{ (t/h)} & \dots & (Q_{\rm M,UF})_{pm}\text{ (t/h)}\\
\end{bmatrix}
\end{bmatrix}


Line 111: Line 188:
(Q_{\rm M,OF})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,OF})_{1m}\text{ (t/h)}\\
(Q_{\rm M,OF})_{11}\text{ (t/h)} & \dots & (Q_{\rm M,OF})_{1m}\text{ (t/h)}\\
\vdots & \ddots & \vdots\\
\vdots & \ddots & \vdots\\
(Q_{\rm M,OF})_{n1}\text{ (t/h)} & \dots & (Q_{\rm M,OF})_{nm}\text{ (t/h)}\\
(Q_{\rm M,OF})_{p1}\text{ (t/h)} & \dots & (Q_{\rm M,OF})_{pm}\text{ (t/h)}\\
\end{bmatrix}
\end{bmatrix}


Line 117: Line 194:


\begin{bmatrix}
\begin{bmatrix}
(P_{\rm OF})_1\text{ (frac)}\\
(E_{\rm oa})_1\text{ (frac)}\\
\vdots\\
\vdots\\
(P_{\rm OF})_n\text{ (frac)}
(E_{\rm oa})_p\text{ (frac)}
\end{bmatrix}
\end{bmatrix}
\\
\\
Line 135: Line 212:


where:
where:
* <math>{\rm DL}</math> is the dust loading (kg/m<sup>3</sup>)
* <math>F</math> is the flow rate of -36+3 µm size particles in the feed (t/h)
* <math>\alpha</math> is the sharpness parameter of the [[Partition (Size, Whiten-Beta)|Whiten-Beta]] efficiency curve
* <math>d_{\rm 50c}</math> is the cut size parameter of the [[Partition (Size, Whiten-Beta)|Whiten-Beta]] efficiency curve (mm)
* <math>C</math> is the bypass parameter of the [[Partition (Size, Whiten-Beta)|Whiten-Beta]] efficiency curve (frac)
* <math>\beta</math> is a fish-hook parameter of the [[Partition (Size, Whiten-Beta)|Whiten-Beta]] efficiency curve
* <math>\beta^*</math> is a fish-hook parameter of the [[Partition (Size, Whiten-Beta)|Whiten-Beta]] efficiency curve
* <math>(Q_{\rm M,OF})_{\rm L}</math> is the mass flow rate of liquids to the overflow stream (t/h)
* <math>(Q_{\rm M,OF})_{\rm L}</math> is the mass flow rate of liquids to the overflow stream (t/h)
* <math>(Q_{\rm M,UF})_{\rm L}</math> is the mass flow rate of liquids to the underflow stream (t/h)
* <math>(Q_{\rm M,UF})_{\rm L}</math> is the mass flow rate of liquids to the underflow stream (t/h)
* <math>P_{\rm OF}</math> is the partition fraction to overflow (frac)


=== Example ===
=== Example ===
Line 159: Line 228:
== SysCAD ==
== SysCAD ==


{{Under construction|section}}
The sections and variable names used in the SysCAD interface are described in detail in the following tables.
 
{{SysCAD (Page, Classifier, DLL*Classifier)}}
 
==== Classifier page ====
 
The Classifier page is used to specify the input parameters for the classifier model.
 
{{SysCAD (Text, Table Header)}}
 
|-
! colspan="3" style="text-align:left;" |''Altun''
 
{{SysCAD (Text, Help Link)}}
 
|-
! colspan="3" style="text-align:left;" |''Parameters''
|-
|Diameter / D
|Input
|Chamber diameter
|-
|AirFlowRate / AF
|Input
|Flow rate of air into chamber.
|-
|RotorSpeed / RS
|Input
|Velocity of the rotor.
|-
|Alpha
|Input
|Coefficient (k) and exponent (n) of the alpha equation.
|-
|d50c
|Input
|Coefficient (k) and exponent (n) of the d50c equation.
|-
|Beta
|Input
|Coefficient (k), exponent (n) and constant (c) of the beta equation.
 
{{SysCAD (Text, Hydrocyclone, Liquids)|method=1}}
 
|-
! colspan="3" style="text-align:left;" |''Results''
|-
|DustLoading / Feed.DL
|style="background: #eaecf0" | Display
|Dust loading of the feed.
|-
|FineSolidMassFlow / F
|style="background: #eaecf0" | Display
|Mass flow rate of -36+3 um solids in the feed.
|-
|Alpha
|style="background: #eaecf0" | Display
|Value of the ''alpha'' parameter of the Whiten Beta efficiency curve.
|-
|d50c
|style="background: #eaecf0" | Display
|Value of the ''d<sub>50c</sub>'' parameter of the Whiten Beta efficiency curve.
|-
|C
|style="background: #eaecf0" | Display
|Value of the ''C'' parameter of the Whiten Beta efficiency curve.
|-
|Beta
|style="background: #eaecf0" | Display
|Value of the ''beta'' parameter of the Whiten Beta efficiency curve.
|-
|BetaStar
|style="background: #eaecf0" | Display
|Value of the ''beta star'' parameter of the Whiten Beta efficiency curve.
 
{{SysCAD (Text, Hydrocyclone, Partition Metrics)}}
 
|}
 
{{SysCAD (Page, Hydrocyclone, Partition)|ActionU=Partition|ActionL=partition|DestinationU=Underflow|DestinationL=underflow|UnitL=classifier}}
 
{{SysCAD (Page, About)}}
 
==== Additional notes ====
 
{{SysCAD (Text, No PSD Splits)|gasstream=overflow}}
 
== See also ==
 
* [[Partition (Size, Whiten-Beta)]]


== References ==
== References ==

Latest revision as of 10:03, 9 June 2024

Description

This article describes the Altun and Benzer (2014) model for high efficiency air classifiers.[1]

High efficiency air classifiers may be alternatively described as dynamic or third generation air classifiers.

Model theory

The Altun air classifier model applies the Whiten-Beta efficiency curve to partition particles to the overflow stream:

where:

  • is the index of the size interval, , is the number of size intervals
  • is the fraction of particles of size interval in the feed reporting to the overflow stream (frac)
  • is the geometric mean size of particles in size interval (mm)
  • is the corrected size at which 50% of the particle mass reports to underflow and 50% to overflow (mm)
  • is the fraction of feed liquids (or fines) split to overflow (frac)
  • is a parameter representing the sharpness of separation
  • is a term introduced to accommodate the so-called fish-hook effect, and controls the initial rise in the efficiency curve at finer sizes
  • is computed to ensure the Whiten-Beta function preserves the definition of in the presence of the fish-hook, i.e. at

Additional relations link terms of the efficiency curve equation with operating parameters.

Corrected cut size

The corrected cut size, (mm), is:

where:

  • is the classifier air flow rate (m3/h)
  • is the rotor speed of the classifier (m/s)
  • is the flow rate of -36+3 µm size particles in the feed (t/h)
  • and are the coefficient and exponent, respectively, of the cut size equation.

Sharpness of separation

The sharpness of separation term, , is estimated by:

where:

  • is the classifier chamber diameter (m)
  • is the dust loading of the classifier feed (kg/m3)
  • and are the coefficient and exponent, respectively, of the sharpness of separation equation.

The dust loading, (kg/m3), is calculated from the feed and air flow rates:

where is the mass flow rate of solids in the feed (t/h)

Fines bypass

The fraction of the finest particles reporting to overflow, (frac), is:

where and are the coefficient and exponent, respectively, of the fines bypass equation.

Fish-hook parameter

The parameter controlling the initial rise of the efficiency curve in fines sizes (fish-hook), , is:

where , and are the coefficient, exponent and constant, respectively, of the fish-hook equation.

Altun and Benzer (2014) also provide an equation for the term of the efficiency equation. However, Whiten's definition of requires its value to be computed in complement to the specified value of in the efficiency equation (see Partition (Size, Whiten-Beta) for more information).

Therefore, the equation is excluded from this implementation of Altun and Benzer's (2014) air classifier model.

Equation parameters

Altun and Benzer's (2014) test work was conducted on a range of Sepol, Sepax and Sepmaster industrial scale dynamic air classifiers. The parameter values in Table 1 were derived by regression analyses of their industrial sampling results.

Table 1. Air classifier model equation parameters (after Altun and Benzer, 2014).[1]
Equation Coefficient, Exponent, Constant,
0.905 1.2679 -
0.4048 0.7775 -
10.467 1.4171 -
0.4417 1.4171 0.1293

This implementation of the air classifier model allows a user to specify the values of the equation coefficients, exponents and constants directly. Altun and Benzer's (2014) values may be used, or new values derived from specific industrial or laboratory test work programmes.

Multi-component modelling

Altun and co-workers have published subsequent journal articles outlining similar model treatments for multi-component feeds, where particle density differences and agglomeration are observed to affect classification performance.[2][3]

However, this work was only conducted on laboratory scale equipment rather than operating industrial air classifiers. Additional non-standard material measurements are also required (e.g. fluidity index). As such, these model implementations are not included here.

Partition metrics

Several metrics are provided to characterise the partition curve.

The , also known as the cut or separation size, is defined as the size of a particle which has an even (50%) chance of appearing in either the underflow or overflow stream. The size is estimated via a log-linear interpolation of geometric mean size () against the uncorrected partition to underflow of all solids in the feed.

The Ecart Probable, or , is a measure of the deviation of a partition curve from a perfect separation, and is typically defined for size classification as:[4]

where and are the sizes of particles which have a 75% and 25% probability, respectively, of appearing in the underflow stream. The and sizes are estimated by log-linear interpolation of geometric mean size against the uncorrected partition to underflow of all solids in the feed.

The Imperfection, , is a normalised measure of the sharpness of separation, which is suggested to be independent of the magnitude of the , and is typically defined for size classification as:[4]

Excel

The Altun air classifier model may be invoked from the Excel formula bar with the following function call: 

=mdUnit_AirClassifier_Altun(Parameters as Range, Size as Range, Feed as Range)

Invoking the function with no arguments will print Help text associated with the model, including a link to this page.

Inputs

The required inputs are defined below in matrix notation with elements corresponding to cells in Excel row () x column () format:

where:

  • is the number of size intervals
  • is the number of ore types
  • is the size of the square mesh interval that mass is retained on (mm)
  • , i.e. descending size order from top size () to sub mesh ( mm)
  • is the mass flow rate of liquids in the feed (t/h)

Results

The results are displayed in Excel as an array corresponding to the matrix notation below:


where:

  • is the mass flow rate of liquids to the overflow stream (t/h)
  • is the mass flow rate of liquids to the underflow stream (t/h)

Example

The images below show the selection of input arrays and output results in the Excel interface.

Figure 1. Example showing the selection of the Parameters (blue frame) array in Excel.
Figure 2. Example showing the selection of the Size (red frame), OreSG (green frame) and Feed (purple frame) arrays in Excel.
Figure 3. Example showing the selection of the Results (light blue frame) array in Excel.

SysCAD

The sections and variable names used in the SysCAD interface are described in detail in the following tables.

MD_Classifier page

The first tab page in the access window will have this name.

Tag (Long/Short) Input / Display Description/Calculated Variables/Options
Tag Display This name tag may be modified with the change tag option.
Condition Display OK if no errors/warnings, otherwise lists errors/warnings.
ConditionCount Display The current number of errors/warnings. If condition is OK, returns 0.
GeneralDescription / GenDesc Display This is an automatically generated description for the unit. If the user has entered text in the 'EqpDesc' field on the Info tab (see below), this will be displayed here.

If this field is blank, then SysCAD will display the unit class ID.

Requirements
On CheckBox This enables the unit. If this box is not checked, then the MassFracToUF option appears below.
MassFracToUF Input Only appears if the On field above is not checked. Specifies the fraction of feed mass that reports to the underflow stream when the model is off.
Method Partition (User) The partition to underflow for each size interval is defined by the user. Different values can be used for different solids.
Partition (Reid-Plitt) The partition to underflow for each size interval is defined by a Reid-Plitt efficiency curve. Different parameters can be used for different solids.
Partition (Whiten-Beta) The partition to underflow for each size interval is defined by a Whiten-Beta efficiency curve. Different parameters can be used for different solids.
Air Classifier (Altun) The Altun air classifier model is used to determine the partition of solids to underflow for each size interval.
Gravity (Plitt-Flintoff) The Plitt-Flintoff gravity classifier model is used to determine the partition of solids to underflow for each size interval.
Options
ShowQFeed CheckBox QFeed and associated tab pages (eg Sp) will become visible, showing the properties of the combined feed stream.
ShowQOF CheckBox QOF and associated tab pages (eg Sp) will become visible, showing the properties of the overflow stream.
ShowQUF CheckBox QUF and associated tab pages (eg Sp) will become visible, showing the properties of the underflow stream.
SizeForPassingFracCalc Input Size fraction for % Passing calculation. The size fraction input here will be shown in the Stream Summary section.
FracForPassingSizeCalc Input Fraction passing for Size calculation. The fraction input here will be shown in the Stream Summary section.
Stream Summary
MassFlow / Qm Display The total mass flow in each stream.
SolidMassFlow / SQm Display The Solids mass flow in each stream.
LiquidMassFlow / LQm Display The Liquid mass flow in each stream.
VolFlow / Qv Display The total Volume flow in each stream.
Temperature / T Display The Temperature of each stream.
Density / Rho Display The Density of each stream.
SolidFrac / Sf Display The Solid Fraction in each stream.
LiquidFrac / Lf Display The Liquid Fraction in each stream.
Passing Display The mass fraction passing the user-specified size (in the field SizeForPassingFracCalc) in each stream.
Passes Display The user-specified (in the field FracForPassesSizeCalc) fraction of material in each stream will pass this size fraction.

Classifier page

The Classifier page is used to specify the input parameters for the classifier model.

Tag (Long/Short) Input / Display Description/Calculated Variables/Options
Altun
HelpLink ButtonModelHelp.png Opens a link to this page using the system default web browser. Note: Internet access is required.
Parameters
Diameter / D Input Chamber diameter
AirFlowRate / AF Input Flow rate of air into chamber.
RotorSpeed / RS Input Velocity of the rotor.
Alpha Input Coefficient (k) and exponent (n) of the alpha equation.
d50c Input Coefficient (k) and exponent (n) of the d50c equation.
Beta Input Coefficient (k), exponent (n) and constant (c) of the beta equation.
Liquids
LiquidsSeparMethod Split To UF (User) Liquids are split to underflow by a user-defined fraction of liquids in the feed.
Split To UF (1-C) Liquids are split to underflow by the C (overflow) fraction specified for the first species in the model.
UF Solids Fraction Sufficient liquids mass is recovered to the underflow stream to yield the user-defined underflow solids mass fraction value (if possible).
UF Liquids Fraction Sufficient liquids mass is recovered to the underflow stream to yield the user-defined underflow liquids mass fraction value (if possible).
UFSolidsFracReqd / UF.SfReqd Input Required value of the mass fraction of solids in the underflow stream. Only visible if UF Solids Fraction is selected.
UFLiquidsFracReqd / UF.LfReqd Input Required value of the mass fraction of liquids in the underflow stream. Only visible if UF Liquids Fraction is selected.
LiqSplitToUF / UF.LiqSplit Input/Display The fraction of liquids recovered to underflow.
Results
DustLoading / Feed.DL Display Dust loading of the feed.
FineSolidMassFlow / F Display Mass flow rate of -36+3 um solids in the feed.
Alpha Display Value of the alpha parameter of the Whiten Beta efficiency curve.
d50c Display Value of the d50c parameter of the Whiten Beta efficiency curve.
C Display Value of the C parameter of the Whiten Beta efficiency curve.
Beta Display Value of the beta parameter of the Whiten Beta efficiency curve.
BetaStar Display Value of the beta star parameter of the Whiten Beta efficiency curve.
d50 Display The separation size, d50, of all solid particles in the feed.
EcartProbable / Ep Display The value of the Ecart Probable of the separation.
Imperfection / I Display The value of the Imperfection of the separation.

Partition page

The Partition page is used to specify or display the partition by species and size values.

Tag (Long/Short) Input / Display Description/Calculated Variables/Options
Distribution
Name Display Shows the name of the SysCAD Size Distribution (PSD) quality associated with the feed stream.
IntervalCount Display Shows the number of size intervals in the SysCAD Size Distribution (PSD) quality associated with the feed stream.
SpWithPSDCount Display Shows the number of species in the feed stream assigned with the SysCAD Size Distribution (PSD) quality.
Partition
Method Model/User Select model-calculated or user-defined partition to separate each solids species type.
Density Display Density of each solid species.
Size Display Size of each interval in mesh series.
MeanSize Display Geometric mean size of each interval in mesh series.
All (All column) Display
  • Actual overall partition to underflow of all solid species, for each size interval.
  • Excludes solid species not present in the classifier feed.
Partition Display
  • Partition to underflow for each size interval, in each solid species, as determined by the selected model or user defined value.
  • Note: These values are displayed regardless of whether the solid species is present in the classifier feed or not.
All (All row, All column) Display
  • Displays the actual, total, partition of all solids with a particle size distribution property in the feed to underflow.
  • Excludes solid species not present in the classifier feed.
All (All row, per species) Display
  • Actual overall partition to underflow for each solid species, for all size intervals in that species.
  • Excludes solid species not present in the classifier feed.

About page

This page is provides product and licensing information about the Met Dynamics Models SysCAD Add-On.

Tag (Long/Short) Input / Display Description/Calculated Variables/Options
About
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Product
Name Display Met Dynamics software product name
Version Display Met Dynamics software product version number.
BuildDate Display Build date and time of the Met Dynamics Models SysCAD Add-On.
License
File ButtonBrowse.png This is used to locate a Met Dynamics software license file.
Location Display Type of Met Dynamics software license or file name and path of license file.
SiteCode Display Unique machine identifier for license authorisation.
ReqdAuth Display Authorisation level required, MD-SysCAD Full or MD-SysCAD Runtime.
Status Display License status, LICENSE_OK indicates a valid license, other messages report licensing errors.
IssuedTo Display Only visible if Met Dynamics license file is used. Name of organisation/seat the license is authorised to.
ExpiryDate Display Only visible if Met Dynamics license file is used. License expiry date.
DaysLeft Display Only visible if Met Dynamics license file is used. Days left before the license expires.

Additional notes

  • Solid species that do not possess a particle size distribution property are split according to the overall mass split of the default particle size distribution species selected in the SysCAD Project Configuration.
  • If the default particle size distribution species is not present in the unit feed, the overall split of all other species with particle size distributions combined is used, as determined by the model.
  • Gas phase species report directly to the overflow stream without split.

See also

References

  1. ↑ 1.0 1.1 Altun, O. and Benzer, H., 2014. Selection and mathematical modelling of high efficiency air classifiers. Powder Technology, 264, pp.1-8.
  2. ↑ Altun, O., Toprak, A., Benzer, H. and Darilmaz, O., 2016. Multi component modelling of an air classifier. Minerals Engineering, 93, pp.50-56.
  3. ↑ Altun, O., 2022. Air classification performances of the components within the varied feed blends. Powder Technology, 399, p.117092.
  4. ↑ 4.0 4.1 Gupta, A. and Yan, D.S., 2016. Mineral processing design and operations: an introduction. Elsevier.
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