Flotation Cell

From SysCAD Documentation

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Contents 1 General Description 1.1 Diagram 2 Inputs and Outputs 3 Model Theory 4 Flowchart 5 Data Sections 5.1 Requirements 5.2 Results 5.3 Size Recovery 6 Adding this Model to a Project 7 Hints and Comments

General Description

The flotation cell mixes perfectly all the incoming feed streams and then, based on the user configuration, calculates the amount, temperature and composition of material reporting to the product streams.

Diagram

The diagram shows the default drawing of the Flotation Cell, with all of the streams that are required for operation of the unit. The physical location of the streams connecting to the unit is unimportant. The user may connect the streams to any position on the unit.

Notes:

1. For a process where the concentrate reports to the float stream in the actual plant, e.g. for the recovery of sulphur minerals, then the Float stream is the Concentrate stream. The Sinks stream is the Tailings stream in this case.
2. For Reverse Flotation, where the concentrate reports to the sinks, the Sink stream is the Concentrate stream. The Float stream is the Tailings stream.
3. When drawing the links, the concentrate stream may be shown coming from either the top or bottom of the unit. For example, for normal flotation the concentrate stream may be shown coming from the top and for Reverse Flotation the concentrate may be shown coming from the bottom.

Inputs and Outputs

Label	Input / Output	No. of Connections		Description
		Min	Max
Feed	In	1	10	The slurry feed/s to the unit
Air	In	0	5	The air feed/s to the unit - Optional
Concentrate	Out	1	1	Concentrate outlet from the unit
Tailings	Out	1	1	Tailings outlet from the unit
Vent	Out	0	1	Vent Stream (Vapour only) - Optional

Model Theory

The Flotation Cell is based on user defined variables that define the solids / liquids split.

There are two Recovery methods available in this model:

1. Overall - The user sets the recovery and grade of the Primary Compound in the concentrate stream. The primary compound is always a solid.
   • The Primary compound may either be a solid specie or an element.
   • If the user selects Elemental, then:

     The user must select a Primary element. (The recovery and grade will be based on this element.)

     The user may also select a Secondary element

     The user may then select an element to Exclude from the recovered compounds.

     The species to be recovered Must contain both the Primary and Secondary elements, but Not the Excluded element. See the example below.

   • The user may also specify the recovery of up to 10 additional compounds in the concentrate stream.
2. Size - this is only applicable if the user has size distribution enabled in the project and the solids in the feed to the flotation cell have size distributions. The user then sets the recovery to the concentrate in each individual size fraction.

There are also two Concentrate Liquid Split methods available in this model:

1. Fraction of Feed Liquids - The user sets the fraction of liquid in the feed to the flotation cell that will report to the concentrate stream.
2. Liquid in Concentrate - The user sets the required fraction of liquid in the concentrate stream.

Example of Overall - Elemental Recovery Method

The feed stream to the flotation cell contains the following solid species:

Cu₂S(s), Cu₅FeS₄(s), CuFeS₂(s), CuO(s), Cu₂O(s), SiO₂(s), CoO(s) and Ore(s)

The user sets the following:

• The Primary element = Cu
• The Secondary element = S
• The Exclude element = O
• The Recovery = 50% and Grade = 65%.

Then the model will recover to the concentrate 50% of all compounds containing both Cu and S, but not O:

Cu₂S(s), Cu₅FeS₄(s), CuFeS₂(s) will be classified as Primary compounds.

The remaining compounds will mainly be sent to the tailings, with sufficient material to the concentrate to ensure a grade of 65% Cu in the concentrate.

Note:
The Size recovery, Exclude Element and the Liquid in Concentrate methods are only available in SysCAD 9.2.

Flowchart

The following shows the sequence of events. See next heading for more information.

Data Sections

The default access window consists of three sections,

1. The first tab has the same name as the model class and contains general information relating to the unit.
2. The Info section, contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents. This is fully described in Common Data Sections.
3. Links tab, only visible in SysCAD 9.2, contains a summary table for all the input and output streams.
4. Audit tab - contains summary information required for Mass and Energy balance. See Model Examples for enthalpy calculation Examples.

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

Tag / Symbol	Input / Calc	Description/Calculated Variables / Options
Common First Data Section
On	Tickbox	If the model is switched off then no separation occurs and all the feed is sent to the tailings stream. If any vapour is present it is sent to the vent stream if it exists, otherwise it is also sent to the tailings stream.
TrackStatus	Tickbox	Enable warning messages if requirements are not met.
Requirements
Recovery Method	Overall	The user sets the recovery and grade of the required compound. This does not require any Size distribution data.
	Size	The user sets the fractional recovery for each individual size interval for all species that do have size distributions. The project must contain any Size distribution data.
Primary Compound
Method	Compound	User may choose a specie as the primary compound for the recovery calculations.
	Element	The user may choose to base the recovery to concentrate calculations on an elemental basis.
Primary Compound	List	List of solid compounds in the current project which can be chosen as the primary compound. This is visible if the user selected Compound as the Method.
Primary Element	List	List of elements in the current project which can be chosen as part of the primary compounds (based on all solid compounds in the project). This is visible if the user selected Element as the Method.
Additional Fields that are visible if Overall Method is selected
Secondary Element	List	Optional: List of elements in the current project which can be chosen to restrict the primary compounds. If a Secondary Element is chosen, then only compounds that contain BOTH the Primary AND Secondary elements will be classified as Primary Compounds. This is only visible if Element is selected as the Method.
Exclude Element	List	Optional: List of elements in the current project which can be chosen to restrict the primary compounds. If an Exclude Element is chosen, then only compounds that contain the Primary (and Secondary, if selected) element, but NOT the Excluded element will be classified as Primary Compounds This is only visible if the user selected Element as the Method. (Please see the example in Model Theory above)
Primary_Recovery	Input	Mass Recovery of the primary compound, or element, from the Feed stream to the Concentrate stream.
Primary_Grade	Input	Mass Fraction of the primary compound, or element, in the concentrate stream.
Additional Compounds to Concentrate (Only visible if Overall Recovery Method is selected.
Number_of_Compounds	Input	Optional: The number of additional compounds to be specified with recoveries. Up to 10 may be specified.
For each additional compound:
Compound	List	List of solid compounds in the current project which can be chosen as an additional compound.
Recovery	Input	Percentage by mass of the additional compound recovered to the concentrate stream.
Concentrate Liquid Split
Liquid Split Method	Fraction of Feed Liquids	Percentage by mass of liquid in feed that is recovered to the concentrate stream.
	Liquid in Concentrate	Percentage by mass of liquid in the concentrate stream.
Results
Primaries_Found	Calc	List of all solid compounds in the project which meet the criteria specified for the primary compound.
Actual_Recovery	Calc	The actual percentage recovery achieved for the primary compound/s.
Actual_Grade	Calc	The actual percentage grade achieved for the primary compound/s.
Gangue_Compounds	Calc	List of all solid compounds in the project which have not been specified as either primary or additional compounds.
Sf_Concentrate	Calc	The percent solids fraction of the concentrate stream.
Sf_Tailings	Calc	The percent solids fraction of the tailings stream.

Size Recovery

If the user selects Size as the Recovery Method, then an additional tab will be visible, called Recovery. This will display a table of the size intervals and the size distributions. The user must enter the recovery for each size interval, as shown below:

In the example shown above, the flotation cell is used to recover KCl(s) - as can be seen by the higher recoveries specified for this specie. NaCl(s) and Insols(s) are gangue solids that are recovered to the flotation concentrate in smaller fractions.

Adding this Model to a Project

Insert into Configuration file

Sort either by DLL or Group.

	DLL:	Separ1.dll	→	Units/Links	→	Separation: Flotation Cell
OR	Group:	Mass Separation	→	Units/Links	→	Separation : Flotation Cell

See Project Configuration for more information on adding models to the configuration file.

Insert into Project

Insert Unit

→

Separation

→

Flotation Cell

See Insert Unit for general information on inserting units.

Hints and Comments

1. If there are some compounds which the user does not want to send to the concentrate as gangue, then include them as additional compounds with a recovery of 0%.
2. It is possible to over-specify the problem, i.e. if the user sets Additional Compounds to recover to the concentrate, this may prevent the Required Grade being met. Note The Required Recovery will always be achieved, but the Grade does depend on feed conditions and the user defined parameters.
3. If an air stream is connected but there is no vent stream, then the user will get a warning but the model will still function.
4. If there is no vent stream, all vapours will be sent to the concentrate stream.
5. The user can not choose the same compound as both a primary compound and an additional compound or twice as an additional compound. In either of these cases the model will not run and the user will be given an error message.