New brickworks for S.P.R. Arbal
Production of hollow bricks with a traditionnal tunnel kiln in Orán, Algeria.
Arbal entrusted Equipceramic with the design, construction and commissioning of its new facilities for producing hollow blocks in Oran (Algeria).
In order to match all our customer’s requirements, Equipceramic designed a high capacity plant equipped with state-of-the-art technology applied to mechanisms as well as to automation, control and adjustment systems aiming to obtain a highly flexible production line.
Clay preparation, grinding and extrusion
A semi-dry method is used for clay preparation consisting of box feeders for the supply of raw material to the clay processing mechanisms. The grinding process is started in a primary crusher and it is completed in a disintegrator followed by a roller mil and a mixer in order to guarantee the most suitable grain size of the resulting mixture.
This mixture is delivered to a clay pit in order to enhance its homogeneity and to provide the plant with a higher autonomy since it guarantees the continuous supply of clay. The clay pit is equipped with a bridge-type bucket reclaimer so clay is collected by an entirely automated system allowing for a more efficient use of the stored raw material.
The shaping process is performed by means of a box feeder, a roller mil and an extruder that shapes raw material into the format of the product to be manufactured.
Products are dried in a semi-continuous dryer equipped with cone-shape air recirculation fans. Dryer cars run on rails through drying tunnels between rows of air-recirculation fans which distribute the air vertically to obtain a higher drying uniformity on all the height of the load.
Hot air required for the drying process comes from the waste kiln recovery system and from some auxiliary generators. Both air flows are mixed in a mixing box and it is drawn out by some centrifugal fans which distribute it all through the dryer.
Dryer cars are handled and unloaded at the exit of the dryer in a fully automated way and dry ware is driven to a setting machine where it is loaded on kiln cars to be fired.
The firing process is preceded by a pre-kiln so temperature increases progressively, thus obtaining a final product of a better colour and minimizing the risk of spalling.
Firing is performed in a thoroughly automated traditional tunnel kiln “FT” operating with gaz. At the exit of the pre-kiln, kiln cars loaded with ware are introduced into the kiln where products are heated by convection and by counter flow to the gases coming from combustion in the firing area. Gases release heat on ware gradually increasing temperature while kiln cars are driven to the firing area.
The kiln is equipped with all required circuits and components to guarantee: an homogeneous hot air flow through the kiln all over the kiln car load, the appropriate pressure at all the stages of the process to maintain the most suitable temperature curve, and the energy efficiency by recycling the resources used in the process.
Kiln regulation and control is also fully automated through a system that allows the customer to comprehensively monitor the drying and firing process as well as to keep a close control of the parameters involved in both processes.
Unloading and packaging
Products are unloaded from kiln cars by means of some grippers that collect the layers of fired products to make horizontally and vertically strapped dispatch packages to ensure their stability.
According to the traditional Algerian type, two gaps are left in the bottom layer of packs so they can be collected by the fork lift.
In this project, grippers set two dispatch pack-high stacks, thus improving the efficiency of lift trucks that take them to the storage area.