Production And Recycling Ielts Listening: Paper

The recycling sequence involves six key stages. First, , where paper is graded by type and quality – for instance, office paper is separated from corrugated cardboard. Next is pulping , where the paper is mixed with warm water and agitated in a huge vat called a pulper, breaking it down into individual fibres.

Now, let’s shift to , which currently supplies around 40% of the world’s paper fibres. The process is far less energy-intensive. Recycling one tonne of paper saves approximately 4,100 kilowatt-hours of electricity – enough to power the average home for six months.

The fifth stage is , where the recovered fibres are beaten to swell and roughen them, improving their ability to bond. Finally, stage six: paper making , where the cleaned pulp is diluted, spread onto a wire mesh screen to drain water, pressed between rollers, and then heated to dry. paper production and recycling ielts listening

Subject: Environmental Science / Industrial Processes Difficulty: IELTS Listening Section 4 Good morning. Today, we’re going to explore the lifecycle of paper, focusing on two interconnected stages: primary production from virgin materials, and secondary production through recycling. This is a critical topic, as the global demand for paper products is projected to rise by nearly 40% over the next decade.

The third stage is . Here, the slurry passes through screens of varying mesh sizes to remove contaminants like staples, plastic films, and glue. Following this, a centrifugal cleaning process spins the pulp to remove heavier objects, such as paper clips and glass fragments. The recycling sequence involves six key stages

In , the wood is ground against a rotating stone. This method yields a high volume of pulp – up to 95% of the wood becomes paper – but the resulting product is relatively low quality, yellowing quickly due to residual lignin. This type is typically used for newsprint and telephone directories.

Stage four is , arguably the most complex step. Air bubbles are forced through the pulp while a chemical – a surfactant – attaches to the ink particles. The bubbles rise to the surface, forming a frothy layer of ink that is skimmed off. This process can remove up to 90% of printing ink. Now, let’s shift to , which currently supplies

However, fibres cannot be recycled indefinitely. Each cycle shortens and weakens the cellulose chains. On average, a paper fibre can be reused between before it becomes too short to form a coherent sheet. At that point, the residue is often converted into lower-grade products like egg cartons or tissue paper, or used as a source of biofuel.

Let’s begin with . The raw material is, of course, wood. Softwood species like pine and spruce are preferred because of their long cellulose fibres, which produce strong paper. The process starts with debarking and chipping the logs. These chips are then subjected to either a mechanical or chemical pulping process.

In contrast, , most commonly the Kraft process, uses a cocktail of sodium hydroxide and sodium sulphide to dissolve the lignin that binds the cellulose fibres together. This produces stronger, higher-quality paper. However, it recovers only about 50% of the wood’s mass, and it requires substantial energy and chemical recovery systems. A single large mill can consume up to 500,000 tonnes of wood annually.