A concrete plant, also known as a batch plant, is a device that combines various ingredients to form concrete

Concrete

Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

. Some of these inputs include sand

Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

, water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

, aggregate

Construction Aggregate

Construction aggregate, or simply "aggregate", is a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined material in the world...

 (rocks, gravel

Gravel

Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...

, etc.), fly ash

Fly ash

Fly ash is one of the residues generated in combustion, and comprises the fine particles that rise with the flue gases. Ash which does not rise is termed bottom ash. In an industrial context, fly ash usually refers to ash produced during combustion of coal...

, potash

Potash

Potash is the common name for various mined and manufactured salts that contain potassium in water-soluble form. In some rare cases, potash can be formed with traces of organic materials such as plant remains, and this was the major historical source for it before the industrial era...

, and cement

Cement

In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...

. There are two types of concrete plants: ready mix plants and central mix plants. A concrete plant can have a variety of parts and accessories, including but not limited to: mixer

Concrete mixer

A concrete mixer is a device that homogeneously combines cement, aggregate such as sand or gravel, and water to form concrete. A typical concrete mixer uses a revolving drum to mix the components...

s (either tilt-up or horizontal or in some cases both), cement batchers, aggregate batchers, conveyors, radial stacker

Stacker

A stacker is a large machine used in bulk material handling. Its function is to pile bulk material such as limestone, ores and cereals on to a stockpile. A reclaimer can be used to recover the material....

s, aggregate bins, cement bins, heaters, chillers, cement silos, batch plant controls, and dust collectors (to minimize environmental pollution).

The center of concrete batching plant is the mixer. there are three types of mixer, Tilt, pan, and twin shaft mixer. The twin shaft mixer can ensure even mixture of concrete and large output, while the tilt mixer offers a consistent mix with much less maintenance labor and cost.

Types

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.

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 temporary batch plant is similar to the central batch plant but it can be constructed on a large job site. A concrete plant becomes central mix with the addition of a concrete mixer.

Automation and controls

Modern concrete batch plants (both ready mix and central mix,) employ computer aided control to assist in fast, accurate measurement of input constituents or ingredients, as well as tie together the various parts and accessories for coordinated and safe operation. With concrete performance so dependent on accurate water measurement, systems will often use moisture probes to measure the amount of water that is part of the aggregate (sand and rock) material while it is being weighed, and then automatically compensate the mix design water target.

Trade shows

There are two main events for manufacturers of concrete plants: World of Concrete and ConExpo-ConAgg. World of Concrete occurs every year; ConExpo-ConAgg occurs only once every three years and is the largest concrete exhibition in the industry.

Concrete Plant Manufacturers Bureau

A non-profit association brings together all of the main concrete plant manufacturers on common matters related to the industry. According to the CPMB's website, "The National Ready Mixed Concrete Association (NRMCA) endorses the members of the Concrete Plant Manufacturers Bureau as the preferred providers of concrete plants and associated equipment as providing quality equipment conforming to the standards and specifications of NRMCA’s plant certification program and the concrete plant manufacturers standards."
"The primary function of the CPMB is to establish minimum standards for rating various components of concrete plants for the protection and assurance to the user that the plated components of the plants conform to these Standards."http://www.cpmb.org/about_CPMB.htm