Coal Dewatering Screen Functioning Principle and Features

A coal dewatering screen is a type of screening equipment created for dewatering, desliming, and degritting of slurry materials. It is extensively used in coal sludge dewatering, stress filtering separation, dewatering, healing of excellent materials, and so on coal dewater screen.

Just How Coal Dewatering Screen Work

The coal dewatering screen takes on double electric motor self-synchronization technology, general eccentric block, and flexible amplitude vibration exciter.

The coal dewatering screen is primarily composed of a screen box, vibratory exciter, support group, and motor. When working, both unconnected actuators are driven by belt combinings to run synchronously and also backward. The centrifugal pressures produced by the two teams of eccentric blocks are superimposed along the vibration direction and neutralized by reverse centrifugation, forming a single fired-up vibration along with the vibration instructions, which makes the screen box move back as well as forth in a straight line.

The sludge going into the coal dewatering screen changes the surface area water stress through the exciting pressure. The slurry water travels through the screen to become the material under the screen. In contrast, the screen panel blocks the fine material to create a filter layer to progress and discharge intoxicated of vibration pressure.

Coal Dewatering Screen Applications

Coal dewatering screen has a variety of exceptional properties and functions of average dewatering screen and accepts thickeners for dry discharge of tailings, which is the best equipment for dewatering and dry discharge of tailings presently. A coal dewatering screen is generally used to classify the tool and refined materials, with a large processing capacity and high screening efficiency.

Coal Dewatering Screen Features

1. Practical framework, suppleness and toughness, reduced noise, and practical maintenance.

2. The slime is dewatered and recovered extensively, and the use effect is excellent.

3. Lightweight, hassle-free disassembly and setting up easy maintenance, and low production price.

4. Little volume and large processing capacity, convenient for the layout of the coal washing plant.

5. The framework of the screen panel is a modular design, and it is convenient to change.

6. Compared with the use of detailed coal sludge filters, filter press, and working out filter centrifuge systems, the coal dewatering screen saves a lot of financial investment.

Vibrating Screen Installation and Operation

A vibrating screen is a sort of filtering mechanical separation equipment which is most typically used in the strong mud treatment of the mining industry.

The vibrating screen is commonly used in mining, building materials, transport, power, chemical, etc. It is used for material classifying, washing, dewatering, and screening. In this article, you will certainly discover the installation and also debugging (test run) of the vibrating screen and also the operation skills to improve the screening efficiency, which will help you to be a specialist in the location of the vibrating screen.

Installation of Vibrating Screen

( 1) Install Supports or Hangers

The installation of each part will be accomplished in sequence in strict conformity with the illustrations of support or lifting, and also the actual strength noted on the completion face shall be matched before the installation of spring parts. The base of the shaker has to be flat and steady.

( 2) Installation of Screen Box

Link the screen box to the sustaining or hanging device, as well as change it according to the defined Inclination after installation. For hanging screens, the inclination angle of the screen box, as well as the degree of the primary shaft of the screen box, shall be readjusted at the same time.

( 3) Install Motor and also V-Belt

Throughout the installation, the base of the electric Motor will be leveled; the motor level shall be remedied, the centerline of the matching groove of both belt wheels shall be overlapped, as well as the tension of the triangular belt will be appropriate.

( 4) Install as well as Secure Screen Panel

( 5) Inspection After Installation

Inspect whether the feed chute, discharge chute as well as receptacle under the screen clash during operation.

Trial Run of Vibrating Screen

Test running time of the vibrating screen is greater than 8 hrs. Observe whether the vibrating screen begins smoothly as well as rapidly, whether the vibration and operation are stable, no special sound, as well as whether its amplitude fulfills the requirements.

When the vibrating screen is running, the vibration of the screen box must not create a horizontal pendulum. If the horizontal pendulum happens, the factor might be that the height difference between the springs on both sides is too large, the stress of the hanging cord rope is unequal, the rotation axis is not horizontal, or the triangular belt is as well tight.

Within 4 hrs of running, the bearing temperature increases slowly and then remains stable. The highest possible temperature does not exceed 75 ℃.

If there is abnormal noise or a sharp increase in bearing temperature after startup, quit right away, examine whether the shaft revolves flexibly and also whether the lubrication is good, and so on, as well as start once again after fixing.

After competing for 2 hrs, quit examining whether the connecting parts are loose or otherwise. If there is any loosening, wait on securing and afterward start.

If there is no fault after 8 hours of operation of the vibrating screen, the installation job can be checked and also approved.

Operation of Vibrating Screen

( 1) Operator shall read the obligation document and also execute the general examination of the equipment prior to working. Check the tension of the triangular belt, the oil degree in the vibrator, the stress of the screen surface, the attachment of the bolts as well as the damages of the screen surface area.

( 2) Start-up of the vibrating screen ought to comply with the process series.

( 3) When the vibrating screen is running, it is essential to examine the functioning problem of the vibration exciter as well as the screen box. The temperature rise of the bearing ought to be inspected after the vibrating screen is quit.

( 4) The shutdown of the vibrating screen should be in conformity with the process sequence. With the exception of special requirements, it is purely forbidden to continue feeding to the screen after stopping.

( 5) During the handover, the evaluation ought to be done well, as well as the problems should be recorded in time.

( 6) In order to stop crashes, assessors ought to maintain their distance.

Exactly How To Improve Screening Efficiency

The screening efficiency straight influences the vibrating screen manufacturing effectiveness, as well as the screening performance, can usually be enhanced by the following means:

• Boost opening up price of screen plate

• Readjust the feeding setting

• Self-cleaning screen plate

• Readjust vibrating screen inclination angle

• Try wet screening

• Adjust the weight

• Control feeding wetness content

• Added taken care of screen

Furthermore, affordable and also scientific installation, debugging as well as operation of the vibrating screen can properly boost the classification performance, lengthen vibrating screen service life and also lower the labor intensity of the operator.

Coal preparation plant processing process

 

What is Coal Preparation Plant

A coal preparation plant is a coal processing plant that includes a series of processes: raw coal screening, squashing, coal washing, separation, tidy coal dewatering as well as sludge recycling. Which can separate coal from contaminations, remove mineral impurities from raw coal and divide it into different specs of products.

The primary products of the coal prep work plant are clean coal, lump coal, and by-products such as tool coal and slime. Usually, coal prep work plants are separated right into:

Coking Coal Preparation Plant: It generates reduced clean ash coal for coking.

Vapor Coal Preparation Plant: It produces fuel to coal for thermal power generation, heavy steam locomotives, boilers, and also raw coal for the chemical industry.

 

Why is Coal Preparation Need

Raw coal is blended with numerous mineral pollutants in the formation process and inevitably mixed with rocks and other pollutants in the roofing system and flooring in the process of mining and transport. So the raw coal must be prepared, the primary function of coal prep work can be summed up as adheres to:

( 1) Get rid of impurities in run-of-mine coal, decrease ash and also sulfur, improve high coal quality and fulfill the requirements of users;

( 2) Separate coal right into different top quality and specs to meet the requirements of individuals, so regarding make effective as well as a sensible use of coal and also save cost;

( 3) After coal cleaning, gangue can be discarded right away, which can decrease void transportation as well as create conditions for extensive use of gangue;

( 4) Coal cleaning can eliminate a lot of the ash and 50%-- 70% pyrite sulfur and decrease the air pollution caused by coal burning. It is the property of clean coal technology.

 

Coal Prep Work Process

Crushing & Screening

A belt conveyor transfers raw coal to the squashing workshop. First, it is pre-evaluated by a circular vibrating screen with a sieve opening of 50 mm. +50 mm materials and added large gangue go into the crusher and are squashed to-- 50mm, then transported to the coal washing workshop along with -50 mm raw coal under the vibrating screen.

Jig Density Separation

In the coal cleaning workshop, the raw coal is dispersed to 2 raw coal buffers by scrape transporters, and two chain coal feeders are fed right into two jigs, respectively. Raw coal is separated into clean coal, tool coal, and gangue in the jigs.

After the medium coal and gangue are dewatered by the bucket elevator, they go into the medium coal and gangue shelter and then transported by the auto as the final products. The clean coal is rated and deleted by a linear vibrating screen with a sieve hole of 13mm, and also the coal under the screen gets in the pit for grading.

Tidy Coal Dewatering

The 13-0.5 mm clean coal in a pit is first dewatered by bucket elevator, second of all dewatered by centrifuge machine, and afterward carried to the tidy coal storage space lawn by belt conveyor as the final product along with the clean coal on the screen.

Flotation

The overflow from the pit gets in the flotation feed swimming pool and is pumped to the pulp preprocessor via the slurry pump. After adding accessories streams into the flotation protection machine, the frothing representative and enthusiast are added to the pulp preprocessor and the coal scum water.

-0.5 mm sludge is separated into clean coal and tailings in the flotation machine. The flotation protection cleans coal streams into the flotation concentrate pool and is pumped to the clean coal filter press for dewatering. The dehydrated flotation protection clean coal is blended with jigging clean coal as the final product.

Tailings Concentration

Flotation tailings moves right into the tailings swimming pool of the concentrator workshop and are afterward pumped to the paste thickener, typically two paste thickeners are called for to wait for each other to ensure that when a mishap happens in the thickener, the slime water will certainly not be drained out.

Slime Management

The filter press dries out the bottom flow of the concentrator(thickener machine), and the filtered scum is moved to the outside of the coal prep work plant. The overflow of the concentrator and the filter's filtrate press circulation into the distributing swimming pool in the focus workshop pumped to the jig for recycling usage.

CRF Circulating Water

The water of the entire coal preparation plant needs to be recycled because the water price much in a wet coal prep work plant, Usually the repeated usage price of water needs to be greater than 90%, as well as the unit supplemental water amount is less than 0.15 m ³/ t (raw coal).

As the coal preparation plant is divided into dry prep work and wet prep work, the coal preparation processes with the jig and heavy tool cyclones typically need to use water as the separator medium, so it is likewise known as a coal washing plant. While the coal handling with air was splitting up, screen separation or manual separation, etc., without water is called a coal preparation plant or dry coal beneficiation.

Generally, all coal washing plants come from coal preparation plants.