Types of Jigging Separation Process, and Advantages

A jig is a mechanical machine used for the separation of materials of different specific gravities by pulsating a stream of liquid flowing through a bed of materials resting on a screen.

Mineral processing is an important step in the mining and extraction of raw materials. It involves separating valuable minerals from ore, which is done most efficiently through a process known as jigging. 

Jigging is a common method of mineral processing and involves the use of a jig, which is a type of mechanical device. In this essay, I will explain the different types of jigs used in mineral processing, their advantages and disadvantages, and how they can be used in different contexts. 

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Jigging is a technique of separating materials of different specific gravity by the pulsation of a stream of water (liquid) flowing through a bed of materials resting on a screen. 

Pulsate -> oscillate => swing back and forth at a regular rate.

Jig = move up and down in a quick jerky motion.

Principle of Jigging Process 

Jigging is a process of gravity concentrated where solids are separated based on the differences in the behavior of particles through a moving fluid which in turn, depends upon specific gravity. The separation of solids of different specific gravities has achieved the pulsation of a liquid stream flowing through a bed of solids on a screen. 

The liquid phase jigs up and down and this action the heavy material to move toward the bottom of the bed and the lighter material to rise to the top. In this method, each product is taken out separately. 

Types of Jigging in Mineral Processing

1. Diaphragm jig 

Diaphragm jig separation is a process used in mineral processing to separate particles based on their specific gravity. This method is used to separate ore concentrates, coal, and other heavy minerals from lighter materials. It is a type of gravity separation that uses a specially designed jig to produce a fluidized bed that allows the heavier particles to settle to the bottom and the lighter material to float to the top.

Components of Diaphragm Jig

1. Jigging Chamber: The jigging chamber is where the separation process takes place. It is typically divided into two sections by a movable diaphragm.

2. Diaphragm: The diaphragm is a flexible membrane or rubber barrier that divides the jigging chamber into two compartments. It can move up and down to control the water flow and stratification of materials in the jig.

3. Water Supply: Water is supplied to the jigging chamber to create a pulsating flow. The pulsation of water is essential for the separation process.

4. Feed Inlet: Raw ore or material is fed into the jigging chamber through a feed inlet, typically at the top.

5. Product Outlet: Valuable minerals that settle to the bottom of the jigging chamber are collected as a concentrate through a product outlet.

6. Tailings Outlet: Lighter gangue or waste material that rises to the top of the jigging chamber is discharged through a separate tailings outlet.

Working Principle of  Diaphragm Jig

1. Raw material is fed into the jigging chamber through the feed inlet.

2. Water is introduced into the jigging chamber, creating a pulsating flow. The diaphragm regulates the water flow, causing periodic expansion and contraction of the chamber.

3. Due to the pulsation, the heavier, denser particles settle to the bottom of the jigging chamber, forming a layer of valuable minerals (concentrate), while lighter particles rise to the top (gangue).

4. The concentrate, which contains the valuable minerals, is collected through the product outlet at the bottom of the jigging chamber.

5. The gangue or waste material is discharged through the tailings outlet at the top of the chamber.

6. Operators can adjust the frequency and amplitude of the water pulsation, as well as the position of the diaphragm, to optimize the separation process for specific ore types and particle sizes.

Advantages of Diaphragm Jigs

• Effective for separating materials with small differences in density.
• Versatile and suitable for a wide range of mineral processing applications.
• Can recover valuable minerals efficiently.
• Relatively simple to operate and maintain.

2. Air Pulsating Jig

An Air Pulsating Jig is a type of mineral processing equipment used in the mining and metallurgical industries to separate materials based on their density. It's a form of gravity concentration equipment designed to efficiently separate valuable minerals from gangue (waste material) by exploiting differences in their specific gravities. Here's an overview of how an Air Pulsating Jig works:

Basic Components of Air-Pulsating Jig

1. Jig Bed: The jig bed is the main separation area where the materials to be processed are placed. It typically consists of a screen or perforated plate to allow the passage of water.

2. Pulsating Mechanism: This is responsible for creating a pulsating or jigging motion in the water within the jig bed. This motion helps to stratify the materials based on their density.

3. Water Supply: Water is supplied to the jig bed to facilitate the separation process. The flow rate and pressure of the water can be adjusted to optimize separation efficiency.

Working Principle of Air Pulsating Jig

Raw materials are fed onto the jig bed. These materials may include a mixture of valuable minerals and waste (gangue). The pulsating mechanism generates a periodic upward and downward motion of the water within the jig bed. This pulsation causes the materials to stratify based on their density, with heavier particles settling lower in the bed and lighter particles rising to the top.

As the pulsating motion continues, the valuable minerals with higher specific gravity sink to the bottom of the jig bed, forming a concentrated layer. At the same time, the lighter gangue materials rise to the top. The concentrated layer is collected as a valuable product, while the gangue material is typically discharged separately.

Operators can adjust the frequency and amplitude of the pulsation, as well as the water flow rate, to optimize the separation process for specific ore types and particle sizes.

Advantages of Air Pulsating Jigs

1. High separation efficiency: They are effective at separating materials with small differences in density.
2. Simplicity: Air Pulsating Jigs are relatively simple to operate and maintain.
3. Low operating costs: They often require less water and energy compared to other gravity separation methods.
4. Versatility: They can be used for a wide range of mineral processing applications, including coal, tin, tungsten, and more.

3. Moving Jigger

A Moving Jigger is not a commonly recognized term in the context of machinery or equipment. It's possible that the term jigger is being used in a specific industry or region with a unique meaning. In such cases, the meaning of the term could vary. 

A Couple of Possible Interpretations

1. In the textile industry, a jigger refers to a dyeing machine used for dyeing fabric or yarn. It typically involves moving the fabric or yarn through a series of rollers and into a dye bath to ensure even and consistent coloration. A moving jigger might refer to a variation of this machine with a different mechanism or movement.

2. In ceramics, a jigger can refer to a machine used for shaping pottery or ceramics. These machines may have a moving element that helps shape the clay or ceramic material into a desired form. A "moving jigger" could indicate a variation of such a machine.

To provide a more accurate explanation or description of a moving jigger it would be helpful to know the specific industry or context in which the term is being used. Different industries may use similar terms for different types of machinery or equipment.

Application of jigging 

1. The jigging process is used for mixtures of heavy minerals with light minerals. 

2. It is commonly employed for bawdy material having a size 20 to 25 mesh and above and where there is a sizeable large difference between the effective specific gravity of the valuable and waste material.

3. Jigs are simple in operation, consume very large quantities of water, and have high tailings losses on metallic ores. They are used mostly to treat iron ores, a few lead-zinc ores, etc. 

4. Mostly Jigging is widely used for the concentration of coal. 

Take these Notes is, Orginal Sources: Unit Operations-II, KA Gavhane