摘要 |
Magnesium ammonium phosphate (struvite), suitable for use as a slow-release fertilizer for example, is produced by mixing animal manure with a pre-specified amount of a magnesium-rich compound. A pre-specified amount of an enzyme, such as an urease or uricase, is added to the resultant mixture. The temperature and pH of this mixture are maintained within a pre-specified range to facilitate precipitation of the magnesium ammonium phosphate. Optionally, the enzyme-supplemented mixture may be inoculated with a pre-specified amount of bacteria, such as Bacillus sphaericus, Bacillus globisporus, or Bacillus fusiformis, or a species of Bacillus identified as Bacillus sp. SB1. This bacteria-supplemented mixture is then allowed to incubate for about 14 days to form struvite. Alternatively, a pre-specified amount of phosphatase, an enzyme promoting the formation of phosphate from phosphorus-rich organic compounds, may be added with the first enzyme to further accelerate the process and increase the yield of struvite crystals.
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