CN106146153B - Potassium and the method for manufacturing carbon-base slow release type composite fertilizer are extracted from urine waste water - Google Patents

Potassium and the method for manufacturing carbon-base slow release type composite fertilizer are extracted from urine waste water Download PDF

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Publication number
CN106146153B
CN106146153B CN201610509905.0A CN201610509905A CN106146153B CN 106146153 B CN106146153 B CN 106146153B CN 201610509905 A CN201610509905 A CN 201610509905A CN 106146153 B CN106146153 B CN 106146153B
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China
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urine
carbon
waste water
fertilizer
potassium
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CN201610509905.0A
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Chinese (zh)
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CN106146153A (en
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汪诚文
徐康宁
李继云
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北京国环清华环境工程设计研究院有限公司
北京林业大学
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    • CCHEMISTRY; METALLURGY
    • C05FERTILISERS; MANUFACTURE THEREOF
    • C05GMIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • CCHEMISTRY; METALLURGY
    • C05FERTILISERS; MANUFACTURE THEREOF
    • C05BPHOSPHATIC FERTILISERS
    • C05B7/00Fertilisers based essentially on alkali or ammonium orthophosphates
    • CCHEMISTRY; METALLURGY
    • C05FERTILISERS; MANUFACTURE THEREOF
    • C05GMIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C05G3/80Soil conditioners

Abstract

Potassium is extracted in disclosing a kind of waste water from urine and the method for carbon-base slow release type composite fertilizer and thus obtained carbon-base slow release type composite fertilizer is manufactured.The present invention can significantly improve the rate of recovery of potassium in urine waste water, and during the urine sewage that the method for the present invention is used for after becoming thoroughly decomposed, the fertilizer for obtaining is carbon-base slow release compound nitrogen phosphate fertilizer, wherein the nitrogenous fertilizer content counted with nitrogen is 4%~6%, it is 20%~30% with the phosphate fertilizer content that phosphorus pentoxide is counted;When the method for the present invention is used for freshly voided urine or has removed the urine sewage of ammonia nitrogen, the fertilizer for obtaining is carbon-base slow release phosphorus potassium complex fertilizer, the potash fertilizer content wherein counted with aoxidizing dipotassium is 15%~20%, is 32%~50% with the phosphate fertilizer content that phosphorus pentoxide is counted.Additionally, the carbon-base slow release type composite fertilizer as obtained in the method for the present invention is rich in organic carbon, and fertilizer efficiency release is slow, can significantly improve lean soil.

Description

Potassium and the method for manufacturing carbon-base slow release type composite fertilizer are extracted from urine waste water

Technical field

The present invention relates to urine waste water reclaiming processing technology field, and in particular to one kind extracts potassium simultaneously from urine waste water The method of manufacture carbon-base slow release type composite fertilizer.

Background technology

Background of related of the invention is illustrated below, but these explanation might not constitute it is of the invention existing Technology.

Fertilizer application excessively, easily causes land fertility decline, soil hardening in China's agricultural.The loose structure of charcoal can With water conservation, fertilizer conservation, prevent the nutrient in fertilizer to be quickly lost in, improve the utilization rate of fertilizer.Contain high concentration in urine Nutrient, contains in every cubic metre of urine and there are about 8 kilograms of nitrogen, 0.8 kilogram of phosphorus and 2.2 kilograms of potassium.Urine waste water separate type is received Collect and carry out recycling treatment, thus prepare can be applied to lean soil improvement slow release fertilizer, can mitigate sewage in nitrogen While the pressure of phosphorus treatment, improve soil fertility, realize the sustainable development of environmental protection and agriculture field.

The content of the invention

For the problems such as nutrient in urine is abundant and soil fertility declines, the present invention proposes a kind of from urine waste water Middle extraction potassium simultaneously manufactures the method for carbon-base slow release type composite fertilizer and thus obtained carbon-base slow release type composite fertilizer.

According to an aspect of the present invention, there is provided one kind extracts potassium from urine waste water and manufactures carbon-base slow release type composite fertilizer Method, comprise the following steps:

(1) forest tree castoff is cleaned and is crushed, be then soaked in magnesium salt solution, soak time is no less than 1h;The magnesium Salt is dissolubility magnesium salts;

(2) forest tree castoff after soaking is pyrolyzed under being placed in the environmental condition of starvation, obtains modification biological charcoal;Pyrolysis Temperature is 400 DEG C~700 DEG C, pyrolysis time is 0.5h~4h;

(3) the modification biological charcoal is added in urine waste water, abandoning supernatant after vibration or stirring collects precipitation Thing, dries or carbon-base slow release type composite fertilizer is obtained after drying.

Magnesium salts in the present invention can be magnesium chloride, and the concentration of magnesium chloride is 100g/L~500g/L in magnesium salt solution.

Preferably, the dosage of modification biological charcoal meets following relation in step (3):

In formula, S is the dosage of modification biological charcoal, and unit is kg/m3;CKIt is the potassium concn in urine waste water, unit is mg/L;V is the volume of urine waste water, and unit is m3;γ is the ratio of potassium and phosphorus concentration in urine waste water, dimensionless unit;CMg It is the concentration of magnesium chloride in magnesium salt solution, unit is g/L;α is the content of magnesium constant in modification biological charcoal, and unit is L/mol.

It is further preferred that working as CMgDuring for 100g/L~300g/L, α=0.08;6 work as CMgDuring for 300g/L~500g/L, α=0.244/CMg

Urine waste water in the present invention can be freshly voided urine or remove the urine sewage of ammonia nitrogen or become thoroughly decomposed Urine sewage afterwards.

The second aspect of the present invention provides carbon-base slow release type composite fertilizer obtained in a kind of method as first aspect present invention.

During the urine sewage that the method for the present invention is used for after becoming thoroughly decomposed, the fertilizer for obtaining is carbon-base slow release compound nitrogen phosphate fertilizer, The nitrogenous fertilizer content wherein counted with nitrogen is 4%~6%, is 20%~30% with the phosphate fertilizer content that phosphorus pentoxide is counted;It is of the invention When method is used for freshly voided urine or has removed the urine sewage of ammonia nitrogen, the fertilizer for obtaining is compound for carbon-base slow release phosphorus potassium Fertilizer, wherein the potash fertilizer content counted with aoxidizing dipotassium is 15%~20%, the phosphate fertilizer content counted with phosphorus pentoxide as 32%~ 50%.Additionally, the carbon-base slow release type composite fertilizer as obtained in the method for the present invention is rich in organic carbon, and fertilizer efficiency release is slow, can Significantly to improve lean soil.

Specific embodiment

Illustrative embodiments of the invention are described in detail below.Description to illustrative embodiments is only For illustration purposes, it is definitely not to the present invention and its application or the limitation of usage.

The present invention provides in first aspect and potassium and the method for manufacturing carbon-base slow release type composite fertilizer is extracted from urine waste water, Methods described comprises the following steps:

(1) forest tree castoff is cleaned and is crushed, be then soaked in magnesium salt solution;

(2) forest tree castoff after soaking is pyrolyzed under being placed in the environmental condition of starvation, obtains modification biological charcoal;

(3) the modification biological charcoal is added in urine waste water, abandoning supernatant after vibration or stirring collects precipitation Thing, dries or carbon-base slow release type composite fertilizer is obtained after drying.

High temperature pyrolysis can form charcoal to forest tree castoff under anoxic conditions, and charcoal has larger specific surface area And microcellular structure, surface functional group enriches, can heavy metal and organic pollution produce suction-operated, so as to reduce pollutant Biological effectiveness and environmental risk, additionally, charcoal has and promoting plant growth, decomposing the effect such as slow.In order to improve life as far as possible The adsorption capacity and adsorption capacity of thing charcoal, the present invention soak forest tree castoff before high temperature pyrolysis using magnesium salt solution.Magnesium chloride Immersion can change the functional group of biological carbon surface, and substantial amounts of magnesium oxide is formed in modification biological carbon surface, on the one hand these Magnesium oxide can be extracted and fix potassium by forming potassium magnesium phosphate precipitation, and on the other hand these magnesium oxides can be with phosphoric acid Root and ammonium ion chemically react, and thus extract and fixed phosphorus, nitrogen.Soak time is no less than 1h, if soak time Too short, magnesium salts cannot fully be acted on charcoal, if soak time is oversize, can increase the week of manufacture carbon-base slow release type composite fertilizer Phase, cost is increased indirectly, reduce the practicality of the inventive method.

In the present invention pyrolysis temperature be 400 DEG C~700 DEG C, pyrolysis time be 0.5h~4h.Although pyrolysis temperature higher C, P and mineral element in modification biological charcoal can be made constantly to be enriched with and increase the specific surface area and water-holding capacity of modification biological charcoal. But pyrolysis temperature is higher, the functional group densities of modification biological carbon surface are smaller, are unfavorable for fully extracting and fixed urine waste water In potassium.

Magnesium salts in the present invention is dissolubility magnesium salts, for example, can use magnesium sulfate or magnesium chloride.Preferably, using chlorination Magnesium prepares magnesium salts, and the concentration of magnesium chloride is 100g/L~500g/L in magnesium salt solution.In the range of finite concentration, in magnesium salt solution The concentration of magnesium chloride is higher, and magnesium is better to the modifying function of charcoal, and the adsorption capacity of gained modification biological charcoal is higher;If chlorination The concentration of magnesium is too low, and magnesium is not obvious to the modifying function of charcoal;If the excessive concentration of magnesium chloride, modifying function will not continue to It is obviously improved, and magnesium is superfluous, can increase the cost for preparing carbon-base slow release type composite fertilizer.

Pyrolytic reaction should be in the environmental condition of starvation, in the present invention, can be by using closed container or logical The mode for entering protective gas forms the environmental condition of starvation.

In some embodiments of the invention, the dosage of modification biological charcoal meets following relation in step (3):

In formula, S is the dosage of modification biological charcoal, and unit is kg/m3;CKIt is the potassium concn in urine waste water, unit is mg/L;V is the volume of urine waste water, and unit is m3;γ is the ratio of potassium and phosphorus concentration in urine waste water, dimensionless unit;CMg It is the concentration of magnesium chloride in magnesium salt solution, unit is g/L;α is the content of magnesium constant in modification biological charcoal, and unit is L/mol.

Preferably, C is worked asMgDuring for 100g/L~300g/L, α=0.086;Work as CMgDuring for 300g/L~500g/L, α= 0.244/CMg

In order that the mineral in modification biological charcoal and urine waste water is fully contacted reaction, mixing speed can be with step (3) It is 100rpm~200rpm, mixing time is 24h.

In the present invention, urine waste water can be for freshly voided urine or after having removed the urine sewage of ammonia nitrogen or having become thoroughly decomposed Urine sewage.During the urine sewage that the method for the present invention is used for after becoming thoroughly decomposed, the fertilizer for obtaining is compound for carbon-base slow release nitrogen phosphorus Fertilizer, wherein the nitrogenous fertilizer content counted with nitrogen is 4%~6%, it is 20%~30% with the phosphate fertilizer content that phosphorus pentoxide is counted.The present invention Method be used for freshly voided urine or when having removed the urine sewage of ammonia nitrogen, the fertilizer for obtaining is that carbon-base slow release phosphorus potassium is answered Hefei, wherein the potash fertilizer content counted with aoxidizing dipotassium is 15%~20%, the phosphate fertilizer content counted with phosphorus pentoxide as 32%~ 50%.

Contain a certain amount of ash content in modification biological charcoal, on the one hand, the part mineral element in ash content can be with modified life The functional groups of thing carbon surface, reduce the functional group that modification biological carbon surface can be combined with the potassium nitrogen phosphorus in urine waste water Quantity, and then reduce the rate of recovery to potassium nitrogen phosphorus in urine waste water.On the other hand, mineral element such as Na, K, Mg, Ca etc. is with oxidation The form of thing or carbonate is present in ash content, is dissolved in after water in alkalescence, and can change urine after being added in urine waste water gives up The pH of water, and then change the chemical reaction process of manufacture carbon-base slow release type composite fertilizer, the mineral of influence carbon-base slow release type composite fertilizer Species and the rate of recovery to potassium nitrogen phosphorus in urine.Based on this, step (2) may further include:Cleaning modification biological charcoal, and Go out ash content therein.

Containing abundant C element in modification biological charcoal, the balance of carbon in soil element can be realized.Fertilizer application in agricultural Excessively, land fertility decline is easily caused, soil hardening, the loose structure of modification biological carbon can improve poor soil with water conservation, fertilizer conservation Earth, strengthens the implicit ability of soil, improves the fertility in soil.Additionally, modification biological carbon surface has absorption complexing to make to phosphorus and potassium With so that phosphorus and potassium are not pure water solubles, realize the sustained release of phosphorus and potassium;The surface of modification biological charcoal can also be special by electric charge Property absorption potassium phosphate magnesium precipitate, make as fertility potassium magnesium phosphate be sustained.

The second aspect of the present invention provides carbon-base slow release type composite fertilizer obtained in a kind of method as first aspect present invention.

With reference to embodiment, the invention will be further described.These embodiments are with regard to the side of being preferable to carry out of the invention Formula is illustrated, and protection scope of the present invention is not read as pertaining only to these embodiments.

Embodiment 1

According to the technological parameter of table 1, potassium is extracted from urine waste water using following steps and carbon-base slow release type is manufactured be combined Fertilizer:

(1) forest tree castoff is cleaned and is crushed, be then soaked in magnesium chloride solution;

(2) forest tree castoff after soaking is pyrolyzed under being placed in the environmental condition of starvation, obtains modification biological charcoal;Pyrolysis Time is 2h;

(3) the modification biological charcoal is added in 5L urine waste water, 200rpm stirring 24h, abandoning supernatant after stirring, Sediment is collected, carbon-base slow release type composite fertilizer is obtained after drying.

Potassium concn C in measurement urine waste waterKWith prepare the potassium concn after carbon-base slow release type composite fertilizer in urine waste water C′K, every group of experiment is measured 3 times, and the rate of recovery R of potassium in urine waste water is calculated according to equation below:

R=(CK-C′K)/CK× 100%

Embodiment 2-12

In addition to the content shown in table 1, embodiment 2 to 12 is carried out with the similar mode of embodiment 1, and calculate urine The rate of recovery R of potassium in liquid waste water.

The rate of recovery of potassium in the technological parameter of table 1 and urine waste water

Embodiment Density of magnesium chloride/(g/L) Soak time/(h) Pyrolysis temperature/(DEG C) The rate of recovery of potassium/(%) 1 50 3 400 75 2 100 3 400 80 3 300 3 400 85 4 500 3 400 88 5 700 3 400 90 6 300 0.5 400 70 7 300 1 400 81 8 300 5 400 85 9 300 3 300 78 10 300 3 550 87 11 300 3 700 89 12 300 3 800 88

As it can be seen from table 1 the concentration of magnesium chloride is unsuitable too small.The rate of recovery of potassium is with forest tree castoff in urine waste water The extension of soak time in magnesium chloride solution and increase, but soak time is more than after 3h, the recovery of potassium in urine waste water The increasing degree of rate is not obvious, from from the point of view of economic benefit, soak time can be made to be maintained at 1h~3h.Pyrolysis temperature pair The rate of recovery of potassium also has an impact in urine waste water, and temperature higher is conducive to improving the rate of recovery of potassium in urine waste water, but warm Higher than 550 DEG C afterwards, the amplification of the rate of recovery of potassium is not obvious in urine waste water for degree, and pyrolysis temperature higher than 700 DEG C afterwards, give up by urine The rate of recovery of potassium has declined on the contrary in water.

Although with reference to illustrative embodiments, invention has been described, but it is to be understood that the present invention does not limit to The specific embodiment that Yu Wenzhong is described in detail and shown, in the case of without departing from claims limited range, this Art personnel can make various changes to the illustrative embodiments.

Claims (6)

1. potassium and the method for manufacturing carbon-base slow release type composite fertilizer are extracted in a kind of waste water from urine, it is characterised in that including following step Suddenly:
(1) forest tree castoff is cleaned and is crushed, be then soaked in magnesium salt solution, soak time is no less than 1h;The magnesium salts is Dissolubility magnesium salts;
(2) forest tree castoff after soaking is pyrolyzed under being placed in the environmental condition of starvation, obtains modification biological charcoal;Pyrolysis temperature For 400 DEG C~700 DEG C, pyrolysis time are 0.5h~4h;
(3) the modification biological charcoal is added in urine waste water, abandoning supernatant after vibration or stirring collects sediment, dries in the air Carbon-base slow release type composite fertilizer is obtained after dry or drying;Wherein,
The magnesium salts is magnesium chloride, and the concentration of magnesium chloride is 100g/L~500g/L in the magnesium salt solution;
The dosage of modification biological charcoal meets following relation in step (3):
S = 0.076 C K V γαC M g
In formula, S is the dosage of modification biological charcoal, and unit is kg/m3;CKIt is the potassium concn in urine waste water, unit is mg/L;V It is the volume of urine waste water, unit is m3;γ is the ratio of potassium and phosphorus concentration in urine waste water, dimensionless unit;CMgIt is magnesium salts The concentration of Chlorine in Solution magnesium, unit is g/L;α is the content of magnesium constant in modification biological charcoal, and unit is L/mol, works as CMgFor During 100g/L~300g/L, α=0.086;Work as CMgDuring for 300g/L~500g/L, α=0.244/CMg
2. the method for claim 1, wherein step (2) is further included:The modification biological charcoal is cleaned, and is gone out Ash content therein.
3. the method for claim 1, wherein formed using closed container or by way of being passed through protective gas every The environmental condition of anoxybiotic gas.
4. the method for claim 1, wherein mixing speed is 100rpm~200rpm in step (3), and mixing time is 24h。
5. the method for claim 1, wherein the urine waste water is freshly voided urine or the urine for having removed ammonia nitrogen Liquid sewage or the urine sewage after becoming thoroughly decomposed.
6. carbon-base slow release type composite fertilizer obtained in the method according to claim any one of 1-5.
CN201610509905.0A 2016-07-01 2016-07-01 Potassium and the method for manufacturing carbon-base slow release type composite fertilizer are extracted from urine waste water CN106146153B (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106964640B (en) * 2017-03-22 2020-04-17 辽宁石油化工大学 Method for adjusting proportion of carbon, nitrogen and phosphorus in petroleum-polluted soil
CN107602211A (en) * 2017-08-30 2018-01-19 常州市海若纺织品有限公司 A kind of method that compound fertilizer is prepared based on rice wine production waste water
CN109609970A (en) * 2018-12-21 2019-04-12 北京林业大学 A kind of magnesium anode galvano-cautery promotes the system and method for potassium recycling in urine waste water

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102775236A (en) * 2012-08-17 2012-11-14 中国科学院广州能源研究所 Agricultural and forestry waste carbon-based slow release filter and preparation method thereof
CN104258812A (en) * 2014-10-24 2015-01-07 江苏省农业科学院 Metal element improved biochar-based nitrate radical adsorbent and preparation method thereof
CN104973919A (en) * 2014-04-11 2015-10-14 清华大学 Method of recycling nitrogen and phosphorus in urine to prepare slow-release fertilizer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102775236A (en) * 2012-08-17 2012-11-14 中国科学院广州能源研究所 Agricultural and forestry waste carbon-based slow release filter and preparation method thereof
CN104973919A (en) * 2014-04-11 2015-10-14 清华大学 Method of recycling nitrogen and phosphorus in urine to prepare slow-release fertilizer
CN104258812A (en) * 2014-10-24 2015-01-07 江苏省农业科学院 Metal element improved biochar-based nitrate radical adsorbent and preparation method thereof

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