SYNTHETIC fibres tend to make low quality clothing. But one of the properties that makes nylon a poor choice of fabric for a shirt, namely its ability to attract and retain dirt and stains, is being exploited by a company that has developed a new laundry system. Its machine uses no more than a cup of water to wash each load of fabrics and uses much less energy than conventional devices.
The system developed by Xeros, a spin-off from the University of Leeds, in England, uses thousands of tiny nylon beads each measuring a few millimetres across. These are placed inside the smaller of two concentric drums along with the dirty laundry, a squirt of detergent and a little water. As the drums rotate, the water wets the clothes and the detergent gets to work loosening the dirt. Then the nylon beads mop it up.
The crystalline structure of the beads endows the surface of each with an electrical charge that attracts dirt. When the beads are heated in humid conditions to the temperature at which they switch from a crystalline to an amorphous structure, the dirt is drawn into the core of the bead, where it remains locked in place.
The inner drum, containing the clothes and the beads, has a small slot in it. At the end of the washing cycle, the outer drum is halted and the beads fall through the slot; some 99.95% of them are collected.
Because so little water is used and the warm beads help dry the laundry, less tumble drying is needed. An environmental consultancy commissioned by Xeros to test its system reckoned that its carbon footprint was 40% smaller than the most efficient existing systems for washing and drying laundry.
The first machines to be built by Xeros will be aimed at commercial cleaners and designed to take loads of up to 20 kilograms. Customers will still be able to use the same stain treatments, bleaches and fragrances that they use with traditional laundry systems. Nylon may be nasty to wear, but it scrubs up well inside a washing machine.
人造纖維通常用來制作低質量衣物。尼龍很容易沾染污漬,這是它不適合用來制作襯杉的原因之一。不過,這項特質卻在一家公司開發的新型洗衣系統中發揮了效用。這種洗衣機每次洗滌用水不超過一杯,耗用的能源也比常規設備少很多。
該系統由一家附屬于英國利茲大學名叫Xeros的公司負責開發,系統內含數以千計的直徑只有幾毫米的小尼龍珠。將這些尼龍珠、臟衣服、少許洗滌劑和水,一起放進小型的雙層同軸滾筒后。滾筒轉動時,水浸濕衣物,洗滌劑讓污漬松脫,然后尼龍珠就會吸附污漬。
尼龍珠的晶體結構會讓表面生成靜電并吸附污垢。當珠子在潮濕的環境中被加熱到一定溫度時,會從晶體結構轉換為非結晶結構。此時污垢會被吸入,并被鎖定在尼龍珠的內核中。
洗滌用時約30分鐘。洗滌周期的末了,外層滾筒會停止轉動。在放置衣物和尼龍珠的內滾筒上有一小溝槽,在它繼續旋轉的同時,99.95%的尼龍珠會透過內滾筒中的小溝槽排出,掉進外滾筒。從機器中拿出衣物時,卡在衣物皺折的尼龍珠會掉進洗衣機門下的收集器里。拿出衣物后,還可以用吸塵器移除卡在口袋等處的尼龍珠。
由于洗滌過程中使用的水量是如此少,同時升溫的尼龍珠也有烘干效果。因此,衣服不太需要烘干。Xeros委托一家環境顧問公司進行測試,結果顯示,這套系統的碳排放量比當前最有效率的洗衣烘干系統還要少40%、用水量少90%,尼龍珠可以重覆使用數百次再回收。
Xeros推出的第一臺機器將定位為容量達到20公斤的商業洗衣機。用戶依舊可以使用傳統洗衣機的去污劑、漂白劑和芳香劑。尼龍也許因為容易變污不適合穿著,但在洗衣機里的表現卻非常亮眼。