Landfill and incineration are not viable options given environmental concerns and expense. The industry is under pressure to find a green, sustainable and cost-effective disposal method.

Garg and colleagues have now tested vermicomposting of solid textile mill sludge that has been spiked with urine-free cow and horse dung, collected from local farms, in a six-month pilot-scale experiment using E. foetida.

The composting process changes the physical and chemical properties of the test mixtures significantly, the team found. The vermicomposts are much darker than the original materials and form a compost-like, homogeneous mixture after 180 days.

The team also found that the earthworms grow well in this manure-enhanced sludge, said a release of the university.

These findings were published in the International Journal of Environment and Pollution.