These are the components of batch asphalt plants.
With the feed bins, the dosage of the material is controlled automatically by electric gear motors and speed regulators on each one of the feeding belts. Each bin has its individual belt. Independent weigh control is done automatically by means of frequency converters.
The counter-flow dryer has characteristics that ensure an effective production of a homogenous asphalt mix with extremely efficient drying. This keeps residual humidity from reaching the mix, which would oxidize the asphalt and harm its properties. The heat is gradually applied to the aggregates and results in highly efficient thermal exchange. The counter-flow drying offers a better use of energy and saves on fuel.
The burner can work with light and heavy fuels and/or gases (LPG or Natural Gas). It uses an efficient mixing control whereby the air-fuel ratio in the mixture can be adjusted either automatically or manually. Its ignition is controlled by the operator using a pilot light, which can also control the filtering and pressure when using LPG or natural gas. With this precise fuel metering and the computer control, the burner has an efficient spray system that can be easily accessed for maintenance and adjustment.
System of sieves
Other than the initial weighing controls of materials at the entrance, the batch plants also have a system made up of vibratory screens for classifying the particles, which classify and separate the aggregates into different sizes. The variable vibration is the process that makes it possible to discard material not within standards and it can include a system for adding filler, polymers, and fibers, as well the weighing and separating fine aggregates.
Pre-collector of particulates®
The Pre-collector of particulates® works as a pre-filter, effectively collecting 80% of the particles when considering all sizes and 100% for particles larger than 200 microns. This makes the filtering elements last longer since the larger particles are the most abrasive and have a higher temperature than the gases.
The material collected in the pre-collector of particulates® is sent back directly into the mixer.
CIBER has developed an exclusive pleated bag filtering system in order to purify the exhaust gases from its plants and comply with the high global standards for environmental protection. Designed in the shape of a cartridge, the pleated bags have a filtering area that is five times greater than the traditional smooth bags, which makes it possible to build a portable plant that is still highly efficient in retaining particles, offering high operational stability even during high production levels.
CIBER's bags filter on the surface (not allowing the fabric to become contaminated), which makes them completely washable. It is an option to wash them if needed, such as in the case of using contaminated fuel. Along with all these advantages, the pleated surface filtering bags facilitate the self-cleaning operation, consuming a lower quantity of compressed air as well as generating a lower load loss in the filter.
The material collected in the bag filter is sent back directly into the mixer
The hot bins are in line, thermally insulated, have load sensors and inspection doors, and have the purpose of storing the previously separated aggregates for a short time, only for weighing. Their flow gates are controlled by the aggregate scale by means of pneumatic valves.
The aggregate scale receives the aggregates coming from the hot bins, which are weighed by flow gates.
This scale controls the hot bin flow gates and receives the aggregates. The system uses electronic sensors in order to integrate (add a+b+c+d) the quantities needed of each material. When the quantity is complete, the entire aggregate is unloaded into the mixer.
The pugmill mixer is completely time controlled and mixes the aggregates in with the PAC. The Pugmill type external mixer is a large metal box with moveable lids and is heated by the circulation of thermal oil that maintains the temperature of the mix during the process. There are also two other parallel shafts that turn in the opposite way with arms, fins, and internal protection built out of high resistant steel. It is powered directly by two gear motors that are synchronized by two reduction gear boxes.