Innovative Solution: Turning Nappy Waste into Affordable Housing Material

Brief

Discover how researchers are turning a major waste problem into a sustainable solution. Used nappies are being repurposed into affordable housing materials, offering an effective method of waste management and a potential breakthrough in cost-effective construction.

Insight

Scientists have found a novel way to confront both the issues of nappy waste and affordable housing. A recent study, published in Scientific Reports, reveals how used nappies can be added to concrete as a partial substitute for sand, contributing to a cost-effective and sustainable solution to waste management and housing.

Siswanti Zuraida, a PhD student at the University of Kitakyushu, Japan, spearheaded the project, recognising the massive waste problem posed by used nappies, particularly in regions without established recycling infrastructures.

The premise of the study was to offer a low-cost recycling treatment for nappies in developing countries. The idea also aimed at repurposing nappy waste as a valuable resource in place of ending up in landfills or incineration. The faecal matter in used nappies was removed with water, and the nappies soaked in a chemical solution to remove urine. The treated nappies were then dried and shredded for use.

Zuraida’s research involved testing the compressive strength of concrete when various ratios of nappy material replaced sand. Sand, an essential component of the concrete mix, increases mortar density, prevents shrinkage, augments volume, and increases the surface area interacting with the binding agent (cement). However, adding more nappies resulted in a decrease in compressive strength.

The researchers discovered they could utilise 1.73m3 of reclaimed nappies in a building with a 36m2 floor area. Structural and load-bearing components could handle a maximum of 10 per cent nappy, while non-structural parts could incorporate up to 40 per cent nappy.

Considering the application of this method in countries like Australia, sustainable construction material researcher Dr Rackel San Nicolas from the University of Melbourne expressed regulatory hurdles to use nappies in concrete on a commercial scale.

However, she emphasised that waste product substitution in concrete is already in practice to make the material more environmentally friendly. This includes replacing cement with fly ash, a by-product of coal combustion, to reduce CO2 emissions.

Highlight

The faecal matter in used nappies was removed with water, and the nappies soaked in a chemical solution to remove urine. The treated nappies were then dried and shredded for use
However, adding more nappies resulted in a decrease in compressive strength.
The researchers discovered they could utilise 1.73m3 of reclaimed nappies in a building with a 36m2 floor area.
Structural and load-bearing components could handle a maximum of 10 per cent nappy, while non-structural parts could incorporate up to 40 per cent nappy.