We all use paper every day, but few people understand the complex processes involved in its manufacture. Knowing how paper is made is essential not only from a functional perspective, but also to understand the environmental impact of excessive consumption of this everyday material.
In this article we will explore in detail how paper is made, from the raw materials used, to its manufacturing and the key stages of the process at an industrial level. We will also look at the environmental implications of its production, the impact of recycling and ways to mitigate its ecological footprint.
How to make paper from a tree
The main raw material for paper is trees. Depending on the type of tree, hardwood or softwood can be used. Softwood trees like fir and poplar are used to make packaging paper and cardboard, while hardwood trees like oak and maple are used for writing paper. But we must keep in mind that this process is closely linked to deforestation and, consequently, to climate change.
The papermaking process begins with the felling of trees selected specifically for this purpose or with wood from controlled plantations. Approximately 15% of the raw materials used in the paper industry come from these plantations, while the rest comes from primary forests that do not always regenerate.
Once the trees are felled, they are processed into wood chips, which are then chemically treated to obtain cellulose using compounds such as sulfite or sulfate. This cellulose is the basis of paper. However, the industry has been a major contributor to deforestation and the depletion of natural resources, leading to greater awareness of the need to promote paper recycling and seek more sustainable alternatives.
Paper consumption around the world
Paper consumption is not uniform worldwide. It is estimated that the average American consumes around 340 kilograms of paper per year , making it one of the countries with the highest per capita paper usage. In Spain, annual consumption is 6 million cubic meters of paper, and approximately 5 million cubic meters of trees are felled annually for its production, representing a serious environmental problem.
Another worrying aspect is the production of paper using trees from primary forests, which are not regenerated, further aggravating the environmental crisis. In countries such as the United States, much of the paper is used for single-use products such as towels, tissues and packaging that are not recycled efficiently.
Fortunately, more and more industrial sectors and consumers are taking steps to use recycled paper. Recycling allows us to reduce the indiscriminate felling of trees and significantly decreases water and energy consumption in paper manufacturing.
Main sources of paper manufacturing
Paper, in its most basic form, is composed of interwoven plant fibers that are held together by hydrogen bonds. Depending on the type of paper, additional substances such as glue, mineral additives, dyes, and other products may be added to modify its functional characteristics.
The main sources from which paper is obtained are:
- Trees: They are the main source of cellulose pulp for making paper. Depending on their bark type and the hardness of their wood, they are used for different types of paper. Hardwood trees, such as oaks, are used for writing, while softwood trees are used for cardboard and packaging.
- Wood waste: It is also possible to take advantage of sawdust, wood waste and other leftovers that, when chemically treated, can form part of the production of paper and cardboard.
- Recycled paper: Recycled paper has gained ground in recent decades as a sustainable alternative. This type of paper does not require additional tree felling, but it does involve chemical processes to remove inks and contaminants, which partially reduces its environmental impact.
Paper manufacturing process: step by step
The paper manufacturing process involves several stages that depend on the type of paper and its required characteristics. Most processes range from pulp preparation to bleaching, pressing and final drying.
A typical paper manufacturing process is detailed below:
- Fiber preparation: Wood is cut into small chips which are then chemically processed to extract cellulose pulp. This pulp is the main raw material for paper. Depending on the type of paper, other fibers such as cotton, hemp or linen may be used.
- Whitening: In this phase, chlorine, hydrogen peroxide or other chemicals are used to remove traces of lignin and other components that give the paper an undesirable color. The goal is to obtain a bright white paper, especially for paper intended for printing purposes.
- Pressing: The pulp is placed in a roller machine that presses it to remove water. Depending on the type of paper, different levels of pressure can be applied to obtain the desired texture.
- drying: Finally, the sheet of paper is completely dried by passing through heated rollers that evaporate the remaining moisture.
In addition to these basic steps, some papers may require additional treatments to improve their shine, resistance or waterproofing.
Environmental impact of paper and its recycling
The paper manufacturing process has a significant impact on the environment. From the felling of trees to the intensive use of water and chemicals (especially in bleaching), each stage has its own implications. Deforestation is undoubtedly one of the most serious consequences of uncontrolled paper use. Every year, millions of trees are cut down, contributing to the loss of biodiversity and the increase in CO2 in the atmosphere.
Furthermore, the paper manufacturing process consumes a large amount of water: it is estimated that producing one ton of paper requires around 20.000 liters of water . Likewise, the paper industry is also one of the largest consumers of energy, contributing to massive CO2 emissions.
For these reasons, paper recycling plays a crucial role. According to industry data, recycling one ton of paper can save approximately 20 trees and significantly reduce water and energy consumption. Paper recycling employs advanced technologies that remove inks and contaminants and prepare recycled fibers for reuse in new paper products.
However, the recycling process also has limitations. Paper can only be recycled a limited number of times before its fibres lose quality. So, although recycling reduces the need to cut down more trees, it is not a definitive solution to the problem.
Digitalisation and reducing unnecessary paper use remain the main strategies to reduce environmental impact.
With all this information, it is clear that we need to raise awareness about paper use and look for more sustainable alternatives such as recycling and the use of waste materials. Reducing paper consumption as much as possible is key to protecting the environment and preserving our natural resources.