Wastewater - Turning Problem to Solution

Revenue generation (US$ billion) Global nutrient potential in wastewater

The recovery of all nutrients from wastewater could offset 13.4 per cent of the global demand for fertilizer (Qadir et al. 2020). However, the current nutrient recovery technologies have not attained 100 per cent efficiency levels (Ward et al. 2018), although significant progress has been made in nutrient recovery from waste streams (Otoo and Drechsel 2018; Saliu and Oladoja 2021). There are promising developments in the use of decentralized source-separating systems to recover nutrients from human waste streams for agricultural application. There are significant economic reasons to develop wastewater reuse. In 2015, Qadir et al. (2020) estimated that the recovery of nitrogen, phosphorus and potassium from wastewater could result in revenue generation of US$ 13.5 billion (figure 2.12), based on maximum theoretical volumes of wastewater produced. Taking into account recent increases in market prices, this value could be two to three times higher (FAO and WTO 2022). In addition to economic gains, there are critical environmental benefits, such as reducing eutrophication of waterways, which is caused by excess nutrients in untreated or inadequately treated wastewater discharge.

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Global fertilizer nutrient demand

Nutrient potential from wastewater

13,4%

Figure 2.12: Global potential of nutrients embedded in wastewater at the global level in 2015, and their potential to offset the global fertilizer demand in agriculture, as well as to generate revenue.

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Source: Qadir et al. 2020; FAO and WTO 2022

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