Hi!

I'm trying to design a struvite reactor providing low cost struvite to compete with chemical fertilizers in Kyrgyzstan.

I was wondering if anyone has tried struvite production in domestic scale/larger scale before in this forum?

I want to combine the same concept that Soilet shared in the thread below. The combination of biochar and struvite is a developing topic and could work if refined into a simple concept that can be taught to people with minimum knowledge on urine reuse in agriculture. There are also some issues that I am trying to confirm at the moment.

For example, the salts accumulation due to struvite (Mg) is not yet studied. Human urine contains some salts (NaCl and such) these might become an issue in the long term as metals (Mg, Cu, Na, etc) form salts as they are released to the soil. It would be a pitty to destroy the fields with a great idea that is not first well studied.

Also finding a cheap magnesium source is an issue that I am trying to solve. So far using MgO or MgSO4 is the most logical option for me. I was thinking about using tree leaves earlier, meaning burning green leaves and using the chlorophyll based magnesium in the ash to try precipitate struvite and Struvite-P but with low success.

What do you think? I am happy to help and answer to your questions too if any should appear. I hope I'm not bringing too many problems to the table with my ranting here. Anyways! Hope to hear your comments! Let's make struvite a champion!

- Santtu

Soilet,
This is equally for very useful for me. I want to precipitate Nitrogen and Phosphorus out of using using MgO and Lime to form Struvite and hydroxyapatite. The urine will be from ecosan toilets and if it proves economic sense will devise means of tapping more urine. This (www.biochar.illinois.edu/docs/20130405-Tao_Xie.pps) presentation has a good way of seperating urine from faeces and procedures of forming struvite. It has also made me think about using biochar, since i have very dry faecal sludge from the FS pilot plant, which just needs carbonising. Our SaniHub aims at producing technologies that will go to scale and make money, so will try different options. Thank you Soilet.
Osbert

Hello Osbert,

I haven't been able to establish a point of contact for the authors, but the Powerpoint is searchable through Google, so I feel is probably to be considered 'open'.

Link is: www.biochar.illinois.edu/docs/20130405-Tao_Xie.pps

If this is incorrect or inappropriate I apologise!

I did not manage to attach it. Need assistance from a teenager I think!

I have just been to the second British Biochar Conference, and am still excited about the possibilities.

Hi Soilet
Am interested in this research could you please seek consent from the author?

Osbert

I have come across an interesting Powerpoint on DropBox investigating the use of Biochar with MgO as a means to stabilise the mineral content of urine, improving the fertiliser potential.

Before I can post the file here I will have to confirm that the author is happy to share it.

If any interest is expressed I will endeavour to obtain consent.

Pages 5 and 6 of this report by Dr Paul A Olivier on Food and Recycling Nutrients, also on Dropbox, probably have relevance to this forum and topic.

dl.dropboxusercontent.com/u/22013094/Pap...es/Food%20Crisis.pdf