| 摘要 |
<p>An inorganic nutrient for treating waste water is prepared by (A) adding 66-80 wt.% urea to 20-34 wt.% phosphoric acid, while agitating at 120-180 rpm, (B) completely dissolving urea at the temperature of lower than 105 deg.C until transparent solution is obtained, (C) reacting the mixture at the same temperature for 10-20 mins, and (E) cooling, drying and crushing neaction prduct in order. In process (A) the ratio of nitrogen to phosphorous is 4-6 and additionally 0.05-0.5 wt.% K2HPO4 MgSO47H2OMnSO4 2H2O is mixed with urea-phosphoric acid mixture. Produced nutrient is used to culture microorganisms to biologically treat industrial or household waste waters.</p> |
