Paper Recycling Explained
Paper recycling is the process of collecting used paper and paper-based products, such as cardboard boxes and office paper, and processing them mechanically and chemically for use in new products like packaging and tissue.
It is a complex and multi-phase process involving conscientious citizens who recycle at home, waste collectors who retrieve paper and paper packaging from refuse bins, small businesses, buy-back centres and paper recycling mills.
Here we unpack the stages of how paper and paper packaging travels from homes, schools and businesses, and eventually to a mill for recycling.
This is the separation of general waste from recyclables at the “source” of use or consumption: homes, offices, schools, retailers and factories, etc. It may involve keeping and storing used paper products in designated recycling containers in our homes, schools, universities, offices and businesses.
Separation-at-source is one of the most important steps in the recycling process as it ensures that paper and paper packaging is kept dry and separate from wet waste and other materials that could contaminate the paper or end up in the recycling process.
Unfortunately, only a small percentage of South Africans separate at source, which means a lot of useful paper gets contaminated by food, liquids and other waste in refuse bins, thereby reducing its suitability for recycling.
Paper and paper packaging needs to be clean and dry so that the fibres retain their structure and integrity.
Waste paper is a raw material for new products and therefore it also has a value. This has led to the rise in the number of waste traders and informal waste reclaimers who will weave their way through cities, suburbs and communities in search of saleable material. You can support their efforts by placing a bag of recyclables next to your bin to reduce contamination, and improve their productivity and earnings.
Consumers are not required to sort paper products into different grades – such as office paper, cardboard and other paper-based items. The sorting of paper categories will be done by collection and sorting infrastructure already available locally. The best thing you can do is keep it clean and dry!
The collection of recyclable material entails several avenues or steps before it reaches the mill.
Collection is usually facilitated by waste pickers, small to medium sized enterprises, or waste merchants who will collect the paper materials (and other recyclables) from your pavement or designated collection points.
Waste management companies also have agreements with large businesses to recover their recyclables and ensure that the materials are sent to recycling processors and mills.
At a buy-back centre, the collectors and traders will bring recyclables and receive money, depending on the volumes and the price per kilogram of the material. The price is variable, depending on market conditions such as supply and demand.
Video Resource | From Bale To Pulp
Watch how paper materials are sorted, graded and weighed at Mpact’s Durban facility. A bale of paper can weigh around one tonne and Mpact produces up to 25 of them an hour.
Sorting and baling
During this stage in the paper recycling process, different paper types are sorted and baled into their different categories. The reason for this is different types of recycled paper call for specific ingredients, from virgin wood fibre to recycled fibre, or a combination of both.
There are several different grades into which paper and paper packaging is sorted. Most mills are guided by the South African Standard Grade Definitions of Recovered Paper and Board.
Once sorted, a particular paper grade is loaded onto a conveyor and fed into a baling machine. These bales will be loaded onto a truck or conveyor and taken to the recycling mill.
Consumers are not required to sort these items at household level.
Here are two common examples of recyclable paper grades:
Used office paper, referred to as Heavy Letter 1 or HL1, is used by tissue manufacturers and will be taken to their production facilities for re-use.
Cardboard, referred to as K3 or K4, is used by companies who manufacture kraft/brown paper reels. These reels are then converted into cardboard boxes and paper bags.
Bales of the same grade are fed via a conveyor into a repulper – imagine a big blender! Water, de-inking agents and chemicals are added to soften the paper fibres forming a slurry or furnish.
The type of paper product being made (e.g. packaging or tissue) will determine what paper grade is used in the recipe.
Once the old paper has been pulped, it is put through a series of screens (sieve-like machinery). This extracts contaminants such as staples, sand, glues and tape from the pulp. Once clean, the pulp is sent to the paper machine for forming and drying.
The end products of this process are jumbo reels of paper. In South Africa, only packaging paper and tissue is made from recycled paper. These reels will be used to convert into various products: fluting, paper bags, cardboard boxes of various kinds. Some mills may sell the reels to converters; others are integrated and will do the converting on-site.
Video resource | From pulp to reel
Video Resource | From Reel To Roll
This video shows the Kimberly-Clark’s tissue production line that operates 24/7, every day of the year.
The jumbo reel will be sent to a converter who will make the required paper product.
Brown kraft paper can made into paper bags or made into linerboard and fluting used in cardboard boxes (containerboard).
Jumbo reels of tissue paper are cut and wound into smaller rolls, the type we purchase at the supermarket.
These paper products eventually make their way to factories to be filled, then shipped to supermarkets and sold for use in our homes, office or school. And the process starts all over again. Except toilet paper of course.