A method and device for rapid recovery of nitrogen and phosphorus nutrients in urine

Abstract

A method for quickly recycling nitrogen and phosphorus nutrient substances in urine comprises the following steps: urine is placed in an airtight stirring device and excess sludge produced after dehydration in a sewage treatment plant is added; the urine and the excess sludge are stirred uniformly and react; after reaction, the urine flows into a vertical separating device and flows out from the top of the separating device, and sludge precipitating at the bottom of the separating device is pumped into the airtight stirring device through a reflux pump; the pH of the urine is adjusted, and then the urine flows into a nitrogen and phosphorus recycling device; magnesium salt and a phosphorus source are added; after reaction, the urine flows into a precipitation device and precipitates to obtain crystals, namely magnesium ammonium phosphate, and supernatant fluid is directly discharged into a municipal sewer system and flows into the sewage treatment plant to be treated. The invention further provides a device for quickly recycling nitrogen and phosphorus nutrient substances in urine. According to the method and the device, microbes are added into fresh urine, and urase generated by metabolism of the microbes is utilized to indirectly catalyze decomposition of urea, so that the recycling effect of nitrogen and phosphorus elements in the urine is improved and meanwhile the recycling cost of nitrogen and phosphorus elements in the urine is greatly reduced.

Description

technical field [0001] The invention relates to a urine separation and treatment technology, in particular to a method and device for quickly recovering nitrogen and phosphorus nutrients in urine. Background technique [0002] Urine contains a large amount of nutrients such as nitrogen and phosphorus. The nitrogen element in the urine just excreted from the human body mainly exists in the form of urea, with a content of 8000-10000 mg / L; the phosphorus element mainly exists in the form of polyphosphate, with a content of 700~2000mg / L. Urine is the main source of nutrients such as nitrogen and phosphorus in domestic sewage. Data show that about 88-98% of nitrogen and 65-71% of phosphorus in toilet wastewater, about 80% of nitrogen and 50% of phosphorus in domestic sewage come from urine. Since nutrients such as nitrogen and phosphorus are important components of fertilizers, recycling the nutrients in urine can solve the problem of high nitrogen and phosphorus loads in sewag...

AI Technical Summary

Problems solved by technology

The patent (CN201010168444.8) method applied by people such as Fu Jinxiang is to add NaOH to adjust the pH of urine, then dosing, stirring and precipitation; For a long time, these methods can promote the conversion of urea in urine into ammonia nitrogen to a certain extent, but there are still great defects in the rate and effect, and the effect is not good in the actual application process.

The effective way to promote the hydrolysis of urea is to add urease. Research data shows that 85% urea in urine can be converted into ammonia nitrogen within 8 hours under the condition of urease content of 50mg / l, but because urease is very expensive, This limits the large-scale application of this method

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