Wastewater - Turning Problem to Solution

level of treatment and the type of nutrient recovery process, anywhere between 10–80 per cent of nitrogen and 33–96 per cent of phosphorus can be removed from wastewater flows (Kanter and Brownlie 2019). Sewage sludge contains around 2.4–5.0 per cent nitrogen and 0.5–0.7

per cent phosphorus (Tyagi and Lo 2013). Human urine is particularly rich in these nutrients (table 2.1) and Simha (2021) estimates that 25 per cent of the global nitrogen and phosphorus demand in agriculture could be met by just recycling human urine-derived nutrients (figure 2.11).

The potential for human urine-derived nutrients to meet global nitrogen and phosphorus demand in agriculture

Nitrogen use replaced by urine

0

25 50 75 100 %

no data

Phosphorus use replaced by urine

0

25 50 75 100 %

no data

Phosphorus and nitrogen use replaced by urine

Less than 25%

>25% to <75 %

Figure 2.11: The potential for human urine-derived nutrients to meet global nitrogen and phosphorus demand in agriculture.

More than 75%

No data

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