With the constant discussion about washers, dryers, detergents and more, laundry bags have always remained out of the spotlight of the laundry industry. However, the pandemic has made laundry operators examine every aspect of their process, and made them realise the effects of using plastic bags to store and transport laundry.
An alternative has existed for years, but is just about taking off in India: water-soluble laundry bags. Apart from generating zero waste and not polluting the environment, they offer a host of other benefits to everyone from hotel owners to laundry attendants. What goes into manufacturing them? Does the wastewater need additional treatment? Why should everyone choose them over conventional plastic bags?
Kavitha Rajan of Green Tech Bio Products, Venkatesh S of Vibha Ecopac Pvt Ltd and Paresh Vakharia of Amtrex Nature Care Pvt Ltd gave us the lowdown.
What are water soluble laundry bags?
These laundry bags are used to collect soiled clothes, then sealed using a tie and put straight into the washing machine. They dissolve completely in a 700C wash cycle and biodegrade safely in the wastewater system, leaving behind just clean laundry and no plastic residue in the machine.
These environment-friendly bags retain all the characteristics of standard plastic laundry bags by being strong and puncture-resistant, with barrier properties.
What makes these bags soluble? They are manufactured using a special polymer technology that uses water-soluble and biodegradable Poly Vinyl Alcohol (PVOH) based pellets. Another type of bag is also soluble in cold water.
While the bags come in various sizes, the commonly used type is around 26”x33”/660mmx900mm with a thickness of 25-30 microns, and a capacity of 3-4 kg to 15 kg.
Time taken to dissolve
According to Rajan, this depends upon the rpm of the machine. “Usually, it takes less than a minute to dissolve in high-speed industrial washing machines.”, she said. Agreeing with her, Vakharia said: “The hot water soluble bags get dissolved in hot water within just 2-3 minutes and cold water soluble bags get dissolved within just a minute or two, depending on the thickness of the bag, temperature of the water, room conditions, abrasion and stirring force of the water, etc.”
Venkatesh has specific instructions: “At 650C, hold for a minimum of 10 minutes within the wash cycle or 710C for not less than 3 minutes”.
Effect on effluent water
One of the biggest pain points for laundry operators is the need to treat wastewater before discharging it into the sewage system, to comply with regulations. While soluble bags do away with the plastic waste that could have polluted the environment, is the effluent containing the dissolved laundry bag also environment-friendly?
Venkatesh explained: “Our polymers are inherently biodegradable. Biodegradation has been observed by at least 20 different genera of bacteria and several yeasts and moulds which occur in activated sludge, compost, facultative ponds, landfills, anaerobic digesters and septic systems and in natural soil and aquatic environments. Sturm (aquatic) biodegradation tests show that the formulations used in the soluble laundry bags degrade in the presence of activated sewage sludge at a similar rate to cellulose.”
In simple words, the bags themselves are inherently compostable, even if not used in a washing machine.
PVOH dissolved in wastewater contributes a very small percentage increase to the organic load of laundry effluent. It will be removed by existing activated sludge systems, has low eco-toxicity and does not persist in the environment. Tests show that the wastewater is well within the permissible limits of the pollution control board for treated sewage. Rajan added: “In fact, the water is naturally non-poisonous and can be even used to water plants as such.”
And what does the PVOH in the water eventually degrade into? Water and carbon dioxide.
Advantages of water soluble laundry bags
- Rajan said: “They provide a convenient and hygienic storage facility for soiled items prior to laundry. The handling of contaminated clothing is very easy as once they are put inside the laundry machine, you need not bother about storage at all.”
- Vakharia explained: “Once the soiled clothes are put into the bag and the bag is tied, there is no need to open the bag again. The bag containing the clothes is put directly into the machine. This prevents contamination; nobody gets infected and laundry handlers are safe.” In short, it minimises contact between staff and potentially contaminated laundry.
- The bag’s material helps to clean and wash the clothes better as it pulls dirt and dust from clothes.
- It saves valuable time of labour. No one has to do the tedious job of segregating clothes after opening the bag.
- Since it dissolves completely, there is no need to find a separate avenue for disposing of the bag, which is required in the case of plastic bags.
- These bags are free of starch and sodium alginate, which are known to clog drains.
- Available in transparent variants, so one can visualise the contents of the bag clearly.
Pathogen dwell time
According to Venkatesh, “They have the added benefits of pathogen dwell time being reduced”. What does this mean?
A recent study compared a sample of Hydropol 30164P (from which Vibha Ecopac’s bags are made) and polyethylene film (used to make conventional laundry bags). Samples of each film were inoculated with E. coli and S. aureus before being placed in a sterile container.
The results showed that after 24 hours, the inoculum counts on the Hydropol films were essentially the same as at the start of the test. On polyethylene film however, the average count was approximately double after 24 hours.
This evidence indicates that the dwell time (or survival) of pathogens on common plastics used to manufacture conventional bags is much greater than on surfaces like Hydropol. Adopting soluble laundry bags automatically reduces the chances of contracting or transmitting an infection that may be harboured in soiled linen.
Cost: Traditional vs soluble
Perhaps the only factor dissuading the laundry sector from abandoning plastic laundry bags and wholeheartedly embracing soluble bags is that the latter are comparatively more expensive. But as Vakharia says, “The price of soluble bags should not be compared to conventional bags, owing to the enormous benefits and advantages they offer”.
Is there demand?
Yes, which has increased exponentially during the pandemic. Said Rajan: “Hospitals and hotels procure such bags as they want to avoid mixing all the rooms’ used linen together. Each room’s linen/patient’s clothing is put inside each of the laundry bags for the respective rooms, and then transported for washing.”
Venkatesh’s company has been manufacturing and supplying these bags to hospitals and hotels in the international market as well as on a pan-India basis. Major hospitality clients include the Shangri-la, Courtyard by Marriott, Holiday Inn, Grand Hyatt, Radisson, The Residency, ITC Hotels, DoubleTree Hilton and the Crown Plaza. Its hospital clients are Apollo Hospitals, CMC Vellore and AIG Hospitals, Hyderabad, to name a few.
He added: “For the Heads of Sustainability within hotel chains, this simple switch to soluble bags also helps solve the ‘coronavirus pollution’ crisis, enabling an increased use of PPE such as bags, aprons and gloves to reduce the risk of pathogen cross-contamination but without increasing their hotel group’s overall plastic pollution footprint.”
A heightened concern for protecting the health of laundry workers, the focus on preventing cross-contamination of linen and an overall trend of choosing sustainable solutions is sure to give an impetus to make water soluble laundry bags the first choice of procurement heads. As demand increases, prices will come down, and even more institutions will opt for this responsible choice.