Cellulose preparation plant process in eyvanit sheet production
The purpose of cellulose preparation, is the production of high flow cellulose in order of fiber expansion without fraction. This means that the fiber after the expansion becomes thinner. Liquid limit of cellulose is measured by a Canadian Standard, Freeness method or C.S.F, according to the ISO 5267/2 standard with the measurement unit of ml and the Schopper Riegler method of SR according to the ISO 5267/1 standard with the measurement unit of degree or (°). The extent of expansion required is a function of production type. (Flat sheet meant for inner use, flat sheet meant for outer use and corrugated sheets)
Without the appropriate expansion, cellulose fiber has the below disadvantages:
A: fibers are too big and rough to use beside cement. In this situation the tensile strength of the product is low and does not have the necessary area to ensure the ultimate tensile strength in fiber cement sheets.
B: The rough and big fibers can’t keep the necessary amount of water in the screen tank. The mesh cracks of the screen tank is bigger than the cement pieces, sillies and other extra materials. So the big fibers can’t stop the escape of these materials and a large portion of these materials exit the screen tank and cause a considerable amount of trouble in the water cycle use.
C: the excessive amount of cellulose in the plasticity production process causes a decrease in the quality. For example resistance against freezing of fiber cement products can decrease, also particle separation and cement parts from the fiber cement area can occur and cause some problems for the color coverage of the product.
Baverce co. cellulose production process is equipped with the below machinery to prevent the above problems:
- Water tank is equipped with water volume controller
- Cellulose feeding system including elevator, equipped with load cell.
- Cellulose pulper with 8 cubic meter velocity and 75 kv power
- Cellulose evacuation pump from the cellulose pulper (Centrifuges type).
- Two opening cycle tanks or refining cellulose fibers.
- Trash rack
- Refiner feeding pump, mohno type, with consistent discharge rate.
- 250 kv disc dual refiner to open or refine cellulose fiber
- Dual cellulose processing tanks with mixer, by the velocity of 100 cubic meter.
- Cellulose transition pump to material building section.