Paper is very commonly seen in our daily life. We consume a lot of paper products such as toilet paper, tissues, paper bags, and writing papers every day. However, since most kinds of paper are made of wood pulp, which is made of trees or other plants, the increase of paper consumption will lead to the decrease of forest area on the earth and damage the natural environment. In order to preserve the forest resources and protect the ecological environment, more and more paper manufacturers choose to recycle the waste paper and make it to waste paper pulp to produce new paper products such as toilet paper and paper egg trays. Now the waste paper has become the secondary fiber material and an important resource for papermaking.
Waste Paper Pulp Production Advantages
1. Wood Preservation
After rough calculation, the production of each ton of recycled newsprint pulp saves 2 more cubic meters of wood than that of 1 ton of groundwood pulp, and each ton of high whiteness deinked pulp saves 5 more cubic meters of wood than that of 1 ton of chemical pulp.
2. Low Investment Cost
The investment cost of a waste paper pulp plant is only 25% to 30% of the cost of a wood pulp plant of the same size. Since the raw material of waste paper pulp is much cheaper than that of wood pulp, the waste paper pulp has a lower cost price.
3. Low Energy Consumption
The waste paper pulp plant consumes less energy during production than the wood pulp plant. The production of 1 ton of high whiteness deinked pulp in waste paper pulp plant consumes 50% energy less than the production of 1 ton of chemical pulp.
What Types of Paper Can Be Recycled to Make Waste Paper Pulp?
Although there are many advantages of recycling waste paper into waste pulp, it should be noted that not all kinds of paper can be recycled. Generally speaking, recyclable paper waste includes old newspapers, office paper, books, enterprise brochures, express boxes, packaging boxes, milk boxes, catalogs, cardboard, etc.
The non-recyclable waste paper includes plastic film, carbon paper, wax paper, plastic glossy waste paper, toilet paper, paper diapers, synthetic paper, etc. In addition, the paper polluted by food and drink is also non-recyclable and should be treated as other garbage.
Waste Paper Pulp Making Process
The waste paper pulp can be divided into two types: deinked pulp and non-deinked pulp. The main difference between their pulping process is that the deinked pulping process includes a deinking process while the non-deinked does not. The deinked process produce high-quality pulp that can be used to manufacture high end paper products, while the non-deinked process is much simpler but the produced pulp can only be used to produce lower end of products such as toilt paper and paper egg trays. *Read more about how to use waste paper pulp to produce paper egg trays and other moulded paper products.
The deinked waste paper pulp making process often involves 4 main steps:
(1) Crushing and dissolving: the recycled waste paper is first classified, and then sent into the hydraulic pulper where it is crushed and deinked;
(2) Filtration: filter the dissolved waste paper raw materials to remove the impurities in the waste paper raw materials;
(3) Concentration and deinking: put the filtered materials into the thickener for concentration, wash and deinking after concentration to remove the floating color on the surface;
(4) Bleaching treatment: the deinked waste paper is bleached and pulped into recycled pulp for paper production;
Here is a more detailed process of deinked waste paper pulp making:
- The waste paper will be sent into the hydrapulper by a plate conveyor for crushing and breaking after it is unpacked.
- The pulp that came out of the hydrapulper will pass through the slag remover and enter the coarse screen, where most of the large-sized impurities in the pulp will be screened out.
- The next process for waste pulp making is pre-flotation, which also aims to remove the impurities in the pulp. Then through heavy and slight slag remover, the purity of the pulp is further increased.
- The pulp will be sent into a thickener. The thickener will concentrate the pulp, increase the pulp concentration, and at the same time wash the pulp.
- The concentrated pulp will then be washed and bleached by a pulp washer and ground to fine pulp by a paper pulper.
- After post flotation, the fine pulp will be sent into the pressure tank, and finally into the pulp pool.
Waste Paper Pulp Equipment
Anyang Machinery is able to design and manufacture a series of equipment for waste paper pulp production.
High consistency vertical hydrapulper is the most commonly used equipment for the waste paper crushing process. It is used to crush and dissolve the waste paper. Under the action of hydraulic and mechanical, the waste paper raw material is passed through the appropriate sieve plate aperture to obtain the pulp with stable concentration. The working concentration of high consistency hydrapulper is 10-15%.
High Concentrating Slag Remover
The slag remover is a kind of equipment that uses the centrifugal principle to remove the impurities in the pulp whose density is different from the pulp. The upper part of the slag remover is made of stainless steel, the lower part is made of polyurethane, and the inner wall of the main body is designed with a spiral cone.
Multi Disc Thickener
Multi disc thickener is a kind of equipment that can dehydrate a large number of recycled paper pulp suspension. It can concentrate the suspension to a concentration of 5-9%.
It uses the height difference to make the water flow in the closed space to produce the vacuum degree, which makes the pulp remove part of the water, and concentrates and screens the good pulp to obtain cleaner filtrate.
Twin Roll Press
Twin roll press is a kind of highly efficient equipment for waste paper pulp washing and extraction of filtrates and pulp concentrates. It is suitable for black liquor extraction and waste paper pulp concentration.
Single Screw Press
The single screw press is a type of squeeze pulp equipment that is used for paper pulp dehydration. It is mostly designed for black liquor of wood pulp, bamboo pulp, wheat straw pulp after cooking and is efficient for the concentration of waste paper pulp.
If you still have questions about waste paper pulp or are interested in waste paper pulping equipment, please feel free to contact us!