A method for simultaneous removal of nitrogen and phosphorus produced during sludge fermentation

Abstract

The invention provides a method for synchronously removing nitrogen and phosphorus generated in a sludge fermentation process. The method comprises the following steps: S1, adjusting the pH (Potentialof Hydrogen) value of sludge in the sludge fermentation process by adopting mixed alkali of NaOH and Ca(OH)2; S2, adding zeolite into the sludge. The method provided by the invention has the beneficial effects that (1) the mixed alkali of the NaOH and the Ca(OH)2 is used for treating primary precipitated sludge and the problem caused by single alkali treatment can be solved; the acid production amount of the sludge can be improved, and PO4<3->-P generated in the fermentation process also can be removed; (2) the zeolite is added into the sludge so that the generation of NH4<+>-N in the sludgefermentation process can be controlled, so that dehydration performance of the sludge is improved; a traditional subsequent nitrogen and phosphorus removing step is omitted, so that manpower and material resources are saved and a new method is provided for removing the nitrogen and the phosphorus in a sludge anaerobic fermentation process.

Description

technical field [0001] The invention relates to the field of sewage treatment and resource utilization, in particular to a method for synchronously removing nitrogen and phosphorus produced during sludge fermentation. Background technique [0002] Anaerobic fermentation of primary sludge can not only make full use of the high concentration of organic matter in the sludge to produce volatile fatty acids (VFAs) as a carbon source, but also realize the reduction and resource utilization of sludge, which has high application potential. Alkaline fermentation can effectively increase the acid production of sludge, and commonly used alkaline reagents include NaOH and Ca(OH) 2 , but there are certain problems. Single use of NaOH to adjust the pH value of sludge can increase the accumulation of VFAs, but it can increase the concentration of NH 4 + -N and PO 4 3- -P content, and destroy the dehydration performance of sludge, which is not conducive to the separation of sludge and ...

AI Technical Summary

Problems solved by technology

Single use of NaOH to adjust the pH value of sludge can increase the accumulation of VFAs, but it can increase the concentration of NH 4 + -N and PO 4 3- -P content, and destroy the dehydration performance of sludge, which is not conducive to the separation of sludge and fermentation broth, and reduces the effect of fermentation broth for biological nitrogen and phosphorus removal.

And the single use of Ca(OH) 2 Adjust the pH value of the sludge, although it can effectively reduce the PO in the fermentation broth 4 3- -P content, Ca 2+ It can also combine with the organic matter in the sludge to form a bridge to improve the dehydration performance of the sludge, but the acid production is low, and it will also produce high NH at the same time 4 + -N

[0003] For NH in fermentation broth 4 + -N and PO 4 3- For the removal of -P, the struvite method is mostly used in research, but additional Mg is required 2+ and PO 4 3- , it is difficult to apply to the removal of nitrogen and phosphorus in fermentation broth

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