How we dry our toilet paper
The push toward sustainable manufacturing is reshaping how everyday products are made, especially in industries that rely heavily on raw materials, water, and heat.
In previous posts we’ve considered the care we take in selecting and transporting the raw materials for our eco-friendly toilet rolls, facial tissues, and kitchen paper towels, and the various ways that our fantastic B Corp factory saves water.
Today, we’re looking at energy. Powering our manufacturing with renewable energy presents a few challenges, from building solar panels to the occasional "blooper roll" when a power dip affects production. But the biggest challenges in sustainable toilet paper production is generating and managing the high levels of heat needed to dry the paper. Luckily, our expert paper makers have a few tricks up their sleeves.
Hand fan at the ready? Let's turn up the temperature.
How was toilet paper made before modern technology?
Every paper product, whether it's soft toilet roll or a sheet of writing paper, begins life as a wet pulp that will be pressed and dried into sheets.
In ancient days, this was a slow, hands-on process, with sheets of wood pulp or papyrus left out to dry on racks or under pressure. The master paper makers of Ancient China would boil bamboo into pulp to make paper, press the pulp into moulds to form sheets, and then hang the moulds to dry on special racks. Once dried the paper could be used for lanterns, writing, and even toilet paper!
Our process is similar, right down to the bamboo we use for our bamboo toilet paper, kitchen paper towels, and tissue boxes. But the stage of drying is quite different. Hanging sheets out in the open air is an effective and sustainable way of evaporating excess water but it’s not exactly practical if you’re trying to churn out the 127 rolls of toilet paper that the average UK resident gets through in a year.
So these days things are a bit more high-tech. Instead of simple sun drying, tissue pulp (the starting material for toilet paper) is spread onto fine mesh and blasted with hot air. This heating stage evaporates water from the wet pulp, giving toilet paper its strength and structure so it can be wound into those rolls we use every day.
Unfortunately, most manufacturers generate this drying heat using natural gas or other fossil fuels, and this stage of manufacture is the biggest culprit driving the high CO2e emissions that are common in the tissue industry.
We’re committed to producing eco-friendly toilet paper, so we’ve moved away from fossil fuels. Our heat comes from renewable biomass and biomethane sourced from local suppliers around our B Corp factory in Spain. If you’re interested to know more about what we mean by “biomass and biomethane” we’ve covered it elsewhere on our blog, but it boils down to twigs from forest maintenance, and methane from big tanks of sheep slurry!
But finding better heat sources is just one piece of the puzzle - getting the absolute most out of every bit of heat is a story in itself.
Our patented system for drying paper
Having gone to all the effort of securing renewable fuel for our furnaces, we want to squeeze every kilojoule for all its worth.
When you generate heat, it naturally dissipates over time, just like how body heat fades when you step outside in winter without a hat. Once the heat that dries our paper drops below a certain temperature, we’d normally need to fire up the furnaces again.
But our ingenious papermaking team has developed a patented two-part drying system that means we can dry more tissue with the same amount of fuel.
Here’s how it works:
Our drying machine features a hood that directs hot air over a large, rotating cylinder, which holds the pulp sheets as they dry. The hood is split into two parts, with each targeting a different drying stage.
The first part of the hood directs the hottest air to the wettest pulp. This area has a larger drying surface and operates at a higher temperature, with a fast air flow, to handle the intense drying needed at this stage. The focused blast of hot air it produces is incredibly effective, producing temperatures of 650°C to get the bulk of the water out of the pulp sheets quickly and efficiently.
But we don’t let warm air go to waste after it’s done the heavy lifting. The "exhaust air" from this stage is redirected to a second part of the hood which covers the part of the sheet that is already partially dry. Getting the last water out of this part of the tissue doesn’t need quite as much heat, so the "dry" part of the hood operates at the comparatively chilly temperature of 405°C!
By keeping the air circulating, we maintain a steady temperature throughout the system, reducing the need for new heat and making the whole process more energy-efficient.
This setup allows us to manage heat much more precisely, so we’re only using the amount we actually need, and our tissue is dried more quickly. This setup brings a significant energy saving over traditional drying systems. We're grateful for the local, renewable biofuel that means we can run our furnaces without fossil fuels, and we're not going to waste any of it!
The big impact of small improvements
We hope you've enjoyed this peek under the hood at our factory!
We’ve come a long way from the flat rocks and sunshine of ancient paper makers, but we like to think the basic idea is similar. Drying paper in the most efficient way means making good use of the materials in your local environment, and refining a process you can sustain.
The drying hood that evaporates the water in every roll of our soft, sustainable toilet paper makes a huge difference to our overall energy efficiency. The local biofuels that fire our furnaces are squeezed for every last degree of usable heat, and our customers get to enjoy the warm glow of knowing they’re at the cutting edge of sustainable design, every time they reach for a roll!
Want to try the UK’s most sustainable tissue products?