How does the stationary concrete batching plant work?

A concrete plant, also known as a batch plant or batching plant, is a device that combines various ingredients to form concrete.
Some of these inputs include sand, water, aggregate (rocks, gravel, etc.), fly ash, potash, and cement.
There are two types of concrete batching plants:
Ready mix plants (A ready mix plant combines all ingredients except for water at  the concrete plant. This mixture is then discharged into a ready mix  truck (also known as a concrete transport truck). Water is then added to the mix in the truck and mixed during transport to the job site)
Central mix plants.(A central mix plant combines some or all of the above ingredients  (including water) at a central location. The final product is then  transported to the job site. Central mix plants differ from ready mix  plants in that they offer the end user a much more consistent product,  since all the ingredient mixing is done in a central location and is  computer-assisted to ensure uniformity of product.)
A concrete plant can have a variety of parts and accessories, including but not limited to:
1. Mixers (either tilt-up or horizontal or in some cases both), The center of the concrete batching plant is the mixer.
2. cement batchers,
3. aggregate batchers,
4. conveyors,
5. radial stackers,
6. aggregate bins,
7. cement bins,
8. heaters,
9. chillers,
10. cement silos,
11. batch  plant controls,
12. and dust collectors (to minimize environmental  pollution).
There are  three types of mixer:
1. Tilt (A more sophisticated version of the machine is the tetra-decagonal  egg-shaped mixer which does 30-60 rpm. )
For  large scale projects, this is  employed using an Archimedes’screw that  hoists the ingredients, mixing  them and then conveying them to the  mixer. At times, the batching  machine may be secured onto the truck  that carries the raw materials and  when they arrive at the site, the  plant equipment mixes the concrete  on-site. The equipment is composed  of a tube, pentagonal to  octagonal-shaped inside. At times, iron balls  are thrown inside to  assist in mixing.
2. Twin shaft mixer.
The twin shaft  mixer can ensure an even mixture of concrete and large output, while the  tilt mixer offers a consistent mix with much less maintenance labour and  cost.
3. Pan concrete mixer:

Working:
The concrete batch plants can be categorized into 4 parts:
aggregate feeding,
powder feeding (fly  ash, cement and expanding agent),
water and
admixture for mixing the  materials, conveyance and storage.
When the control system of mixer is  connected to an electricity source, the operation interface of the  man-machine interaction will appear and system will begin to process  initialization which includes the formula number, concrete slump,  concrete grade and productivity.
Each silo and weighing hopper is tested  according to weighing system. Its control system will output the signal  of the amount of material to prompt the operator to decide whether to  start the control program or not.
The belt conveyor is initiated to transmit the aggregate to the weighing hopper; the  valve of the fly ash and cement tank should be opened and the screw  conveyor and motor initiated to transmit them into the weighing hopper;
The control valve of the water sump and admixture sump needs to be  opened to make water and admixture flow into the weighing hopper.
Once  the weight of all material types meets the needs of specific amounts,  the door of the weighing hopper is opened automatically.
The materials  will then be mixed by a concrete mixer. Once the setting time is over,  the loading door of the concrete mixer opens and the concrete flows into  a concrete mixer trucks.
This process is conducted very carefully since concrete must not  segregate and also because the concrete must be ready and transported  and then used before its preliminary setting time which is between 30-45  minutes.In some countries, this is carried out  by a mobile concrete batching machine.