For some batches, the calcium chloride and urea have been successfully substituted, respectively, by carbide sludge, an industrial waste, and human urine.
To do this, NTU's civil and environmental engineering department is formulating recipes that mix seawater, calcium chloride, urea and an enzyme from soyabeans.
So you stir, about a teaspoon of calcium chloride into 500 mils of water, and that becomes the calcium bath, that we're gonna drop all of our liquids into.