Biochar captures N & P in dairy wastewater

Biochar can be used to capture essential nutrients from dairy wastewater and improve soil physico-chemical properties

dairy wastewaterAbstract.

“Recently, the potential for biochar use to recapture excess nutrients from dairy wastewater has been a focus of a growing number of studies. It is suggested that biochar produced from locally available excess biomass can be important in reducing release of excess nutrient elements from agricultural runoff, improving soil productivity, and long-term carbon (C) sequestration. Here we present a review of anew approach that is showing promise for the use of biochar for nutrient capture. Using batch sorption experiments, it has been shown that biochar can adsorb up to 20–43% of ammonium and 19–65% of the phosphate in flushed dairy manure in 24h. These results suggest a potential of biochar for recovering essential nutrients from dairy wastewater and improving soil fertility if the enriched biochar is returned to soil. Based on the sorption capacity of 2.86 and 0.23mg ammonium and phosphate, respectively, per gram of biochar and 10–50% utilization of available excess biomass, in the state of California (US) alone, 11440 to 57200 tonnes of ammonium-N and 920–4600tonnes of phosphate can be captured from dairy waste each year while at the same time disposing up to 8–40 million tons of excess biomass.”

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Biochar captures N & P in dairy wastewater — 1 Comment

  1. Sorry, I just noticed that I’ve posted on this paper already. But with N pollution issues bubbling in NZ water-table, it won’t hurt to recirculate. Interesting also, regarding P capture. Expert advise is that biochar is not so effective of P retention. This study points to a counter view? I guess it could be about finding the best biochar (biomass and process conditions) for P capture or post-production methods to modify the biochar.

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