<aside> 💡 People have had ideas to turn feces into charcoal, biogas, fertilizer, etc. but we wanted to see if we could also do something with urine. We've come up with a hypothesis to extract the ammonia gas from urine and have it react with sulphuric acid to create ammonium sulfate. Ammonium sulfate can then be sold at $66.64 USD/kg and profit can be made to incentive people to continue using the toilet.
Picture of what this could look like from a prior experiment done in Finland.
We know that with 700mL of urine we can make 24kg of a compound that is 89% hydrogen triammonium disulfate and 11% ammonium sulfate.
That means ~2.4kg is ammonium sulfate and since the calculation initially made within the paper above is in kg/m^3 that means we produce 2.4kg per m^3 of urine. I wanted to convert the m^3 to mL so it's easier for us to calculate things. Since 1m^3 is 1,000,000mL, this would mean we produce 2.4kg/1,000,000mL of pee and a person on average pees 24,000mL/month (800mL/day * 30 days) and if we do the cross multiplication this means we produce 0.0576kg per person per month of ammonium sulfate.
We know that 1kg of ammonium sulfate = $66.64 according to this and we produce 0.0576kg, so if we do the cross multiplication this means we're making $3.84 per person per month.