the needs of pumping in the pulp and paper industry can be quite challenging as the raw material is extremely difficult to transfer. Furthermore, various chemicals are used to obtain the required quality of the final product and also the process is significantly temperature sensitive. Keeping all these requirements, the pneumatic pumps are designed to be robust, durable and highly efficient.
Four main types of ingredients that are used as raw material for cellulose
> Waste paper is recycled to make pulp
> Sawdust is recycled to make pulp
> Cotton or other natural fiber is used to make pulp
> Tree trunks are the most commonly used to make pulp
> Mechanical and chemical processes can be used to convert wood logs into pulp.
In the mechanical process, chopped wood logs are poured into huge drums to remove the bark. This debarked wood is then crushed between huge turntables to make pulp. The pulp is then filtered to remove any foreign particles.
In the chemical process, the debarked wood is cut into small pieces of wood. These wood chips are sent to large digesters to be cooked under pressure in a solution of water, sodium, sodium hydroxide and sodium sulfate. After a few hours of pressure cooking in this solution, the wood chips dissolve into pulp.
The pulp is then sent for crushing and compression in a process called 'Beating'. Various fillers such as titanium dioxide can be added at this stage. These additives determine the color, opacity and other qualities of the finished paper. The absorbency of the paper is also controlled at this stage, in a process called sizing, which involves the addition of fine clay, resin or starch.
This pulp is then pumped into large automatic papermaking machines. In this machine, the pulp is placed on a moving belt of fine mesh screen. The pulp on the belt is compressed by a series of rollers while the suction device is used to remove excess water from the pulp.
Then, in the pressing section of the machine, the pulp is pressed between the rollers and the wooden felt. The paper then passes through a series of heated rollers to remove any remaining water.
Finally, this paper is rolled into large spools for further processing. Paper is smoother and more compacted as it passes through rollers called calendars, which give the paper the desired finish, whether matte or smooth, glossy or matte. More finished in the form of chemical or pigmented coating can be added to the surface of the paper, gloss can be added in a process called super calendar layering and then the paper is cut to desired sizes.
| MAIN PUMPED FLUIDS IN THE PAPER AND PULP INDUSTRY |
| Alkenyl succinic anhydride (ASA) |
| Alkyl Ketene Dimer (AKD) |
| Alum |
| aluminum chloride |
| Aluminum sulfate |
| Bagasse |
| liaison agent |
| Biocide |
| black liquor |
| Calcium carbonate |
| calcium stearate |
| Carbon dioxide |
| caustic soda caustic soda |
| Cellulose |
| Cellulose acetate |
| chinese clay |
| Coloring agent |
| Cor |
| Cooked Starch |
| Anti-foaming agent |
| dispersing agent |
| Effluent |
| Glues and paste |
| green liquor |
| Hydrogen peroxide |
| Caulino |
| kitchen coating paste |
| Latex |
| lemon milk |
| low density pulp |
| Medium / high consistency pulp |
| melanin |
| mineral fillers |
| Neutral sizing |
| optical brightener |
| Paper sludge |
| paper softener |
| Plastic pigment |
| Polyacrylate acetate |
| Polyacrylamide |
| Polieletrolite |
| Polymer |
| polyvinyl acetate |
| polyvinyl alcohol |
| Rags / coated paper |
| retention agent |
| Resin |
| Dimensioning of chemical products |
| Sodium carbonate |
| Sodium hydroxide |
| Sodium Sulfide |
| starch paste |
| Sulfate / Sulphite Pulp |
| talcum powder |
| Titanium dioxide |
| Cera |
| White paper |
