Secondary, but not second-rate: possibilities and limitations

Recently, we encountered a strong objection from a paper manufacturer stating that cellulose can only be produced from primary resources. Secondary cellulose, i.e. obtained from recycled raw materials is not cellulose at all. In this worldview, you can only make new paper by cutting down a tree. Never before has a paper manufacturer been so far from the truth.

Primary and secondary resources: explained
Primary raw materials are those resources that are extracted from the environment. For example, aluminum to make an aluminum soda can. Wood to make a paper label and stick on this can. And finally, oil, to make a plastic straw to drink the soda.

Secondary raw materials are resources that are generated in our homes, offices, production and other facilities. We are talking about waste: municipal, household, industrial, construction, etc. Waste can be recovered to become secondary raw material for the production of new products through recycling. 

The key difference between primary and secondary raw materials is how they are extracted. Primary raw materials are extracted from the environment, which depletes its reserves. Secondary raw materials are extracted from waste, which, on the contrary, reduces ecological footprint.

Possibilities and limits of secondary raw materials
Secondary raw materials offer significant economic and environmental advantages. Instead of extracting natural resources to make new goods, you can extract them from waste by recycling end-of-life products made from plastic, glass, metal or paper. Unfortunately, recycling has its limitations. Many fractions can be recycled only a certain number of times, after which the material loses its properties and becomes unsuitable for the production of new goods. Let’s look at the most common fractions of MSW in more detail.

Glass is made from quartz sand with the addition of dolomite, soda, limestone and cullet (used glass). Any glass container can be recycled an infinite number of times. The quality and properties of the recycled glass will be the same as that of primary material.

Different types of metal are mined from different ores or melted down from used metal goods - aluminum or tin cans, any metal parts. Metal, like glass, can be recycled an infinite number of times. The properties of the recycled material will remain the same.

An unknown fact to many: almost all plastic is made from oil. But it can also be made from waste. Alas, plastic can be recycled only 2-3 times. With each cycle, the properties will deteriorate: its polymer chain becomes shorter and the quality decreases. Most often, a small amount of virgin plastic is added to the batch of secondary one so that the goods produced from recycled materials have a competitive quality. 

Recycled cellulose: advantages and disadvantages
Finally, paper. It is made from cellulose fibers. Cellulose can be obtained from wood - in this case we get primary cellulose fiber. Alternatively, you can recycle waste paper and get secondary cellulose.

An ordinary sheet of paper can be recycled 4-7 times with loss of properties, depending on the type of paper. Long-grain white office paper offers the most flexibility in recycling. In contrast, newspapers with shorter fibers can only be used to make new newspapers or other low quality paper.

Perhaps the paper manufacturer mentioned at the beginning of the article was so strict about recycled cellulose, because its properties differ from those of primary fiber. With each recycling round, the fibers become shorter, coarser and stiffer, which limits the scope of its use. For example, it is no longer possible to make white office paper from recycled cellulose - the fibers are too short. But it can be used to produce napkins, egg packaging, kraft paper.

Moreover, sometimes short cellulose fibers are a plus. For example, long fibers are vulnerable to chemical and physical damage. Recycled paper, on the other hand, is made up of a mass of compressed fibers, making it resistant to high temperatures, solvents and petroleum products.

Conclusion: secondary raw materials are a resource that can be used to produce new goods. Although it has production limitations, recycled materials have a number of economic and environmental benefits. Therefore, manufacturers should increase the share of recycled materials in production.