Recycling has a long history in spinning mills. It has gone from utilising rotor-spinning machines to making yarn out of ring-spinning mill waste. With the growing importance of the circular economy and recycling, being able to spin even the shortest fibres has become more essential than ever.
In the past, ring mills often invested in a few rotor-spinning machines to utilize comber noils and other short fibres resulting from the ring-spinning process. Although this was maybe not originally called recycling, it was the first development step. Mechanical recycling has already been around a while as i.e., integrated mills have used cutting waste etc. Today mechanical recycling of pre- and post-consumer waste is growing.
Here the challenge lies in managing the high short fibre content in the spinning process. This influences the quality of end products and fibres cannot be used unlimited times. In future, manufacturers will therefore also depend on “chemical” recycling to create regenerated fibres, also for natural fibres.
Majority of today’s mechanically recycled fibres are rotor-spun
Saurer’s rotor-spinning portfolio offers excellent features for processing a high short fibre content. This along with the highest raw material utilization has made Saurer a market leader in this field.
Autocoro 10 offers excellent features for recycled fibres. SynchroPiecing 36 helps to ensure that yarn breaks are not an issue anymore. The spin-box is developed to allow exchange of relevant components in order to adapt to spinning short, recycled fibres and to maximizes fibre utilization. Autocoro 10 now offers up to 25% more doffing capacity – useful for spinning coarser yarn. With a higher number of package doffing units that prevent fluff in the area of the spin box combined with the new Vacuum Trash Cleaner, Autocoro 10 offers excellent cleaning options.
Autocoro has been a star in the recycling fibre production for quite some time already. However, the Saurer textile laboratory is always pushing boundaries in yarn creation, i.e. with 100% mechanically recycled cotton fibres (60% pre- and 40% post-consumer waste), the company’s technologists managed to produce encouraging yarn results for knitting.
For 50 years, the semi-automatic BD series has enabled sustainable spinning. It adapts perfectly to changing raw material trends in the semi-automatic market – from virgin to recycled fibres.
Ring spinning and recycled fibres
Processing recycled fibres in ring spinning is challenge, as the drafting zone requires a certain minimum fibre length in order draft properly. Although ring frames can process almost all fibre types, higher short fibre content tends to result in a higher number of yarn breaks and higher waste, resulting in the share of recycled fibres being considerably lower than in rotor spinning..
Saurer Z 72XL offer features offering flexibility and efficiency in processing recycled fibres – from fine counts to coarse counts with 54 mm ring & 260 mm tube length. This includes the automatic control and adjustment of spindle speed depending on the number of yarn breaks (OptiSpeed) for higher efficiency.
The flexibility- and quality-determining features of Texparts drafting components (i.e. weighting arm PK 2630 with numerous adjustment settings combined with top apron cradle) show that components and settings have a high impact on yarn quality.
Currently the demand for ring-spun recycled yarn is increasing and the Saurer textile laboratory is running tests for customers in order to optimise their processes In trials for several customers, Saurer has spun different combination of waste and virgin fibres and in some cases was able to increase speed with up to >10%, resulting in a measurable productivity gain.
The circular economy is a new megatrend and textile industry will adapt. Saurer is focusing its innovation and technology on enabling this in its part of the textile value chain. Through its machine portfolio and its textile laboratories, the company is looking forward to supporting customers on their quest for efficiency and quality in recycled yarn spinning.