CN102180581A - Method for dehydrating and conditioning sludge and preparing raw materials of slow-release fertilizer - Google Patents
Method for dehydrating and conditioning sludge and preparing raw materials of slow-release fertilizer Download PDFInfo
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- CN102180581A CN102180581A CN2011100248465A CN201110024846A CN102180581A CN 102180581 A CN102180581 A CN 102180581A CN 2011100248465 A CN2011100248465 A CN 2011100248465A CN 201110024846 A CN201110024846 A CN 201110024846A CN 102180581 A CN102180581 A CN 102180581A
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- release fertilizer
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/40—Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse
Abstract
The invention relates to a method for preparing a slow-release fertilizer, in particular provides a method for dehydrating and conditioning sludge and preparing raw materials of the slow-release fertilizer. The method particularly comprises the following steps of: adding water-absorbing clay minerals, a mixture of water-absorbing macromolecular compounds and plant residues to dehydrated sludge in each cubic meter, composting and fermenting for 10-15 days according to a conventional method, sequentially adding compounds formed by phosphoric acid radicals and ammonium ions and magnesium-containing alkaline substances in fermentation products, and mixing uniformly to obtain the raw materials for producing a slow-release type organic-inorganic compound fertilizer. The method for dehydrating and conditioning the sludge and preparing raw materials of the slow-release fertilizer, disclosed by the invention, is suitable for large-scale sludge dehydration treatment and also provides high-nutrient raw materials for the manufacturing of the slow-release fertilizer.
Description
Technical field
The present invention relates to a kind of making method of sustained release fertilizer, the method that specifically provides a kind of sludge dewatering conditioning and make the sustained release fertilizer raw material.
Background technology
Along with the increasing of country to the environmental improvement dynamics, the increasing Sewage Plant of China puts into operation, and the mud that is produced is also more and more.Be subjected to the influence of wastewater treatment in China circle " the light mud of heavy water " tendency, the sanitisation of mud, harmless treatment handling problems do not obtain paying attention to always and solve, the mud overwhelming majority of China is thrown aside or landfill at present, and the mud after handling does not so all reach relevant environmental emission standard, simultaneously a large amount of soils be need take again, serious secondary pollution and new environmental problem also caused.Realize sludge reduction and recycling, reduce the ultimate disposal amount of mud, be one of main task of facing of Environmental Protection in China department, and adopt sludge composting, composting technology to become the important measures of mud decrement and recycling.
The mud composting need contain the low mud raw material of moisture, but the dewatered sludge water content that sewage work produces reaches 75%-80%, therefore the moisture content that how to reduce mud becomes " bottleneck " of sludge treatment technology, can reduce the moisture content of mud by the high temperature of compost generation, realize the slaking of material, reach hygienic standard.This respect has a large amount of patent reports, and its method mainly is to add a large amount of dewatered sludge or organism siccative, is adjusted to the required moisture content of compost, further reduces the moisture content of windrow again by the high temperature (60-70 ℃) that produces in the composting process.The dewatered sludge add-on is lower when making in this way compost, and mud handling capacity is very low.
Summary of the invention
The present invention be directed to above problem, a kind of sludge dewatering conditioning and the method for making the sustained release fertilizer raw material are provided, it not only is applicable to and large batch of mud is carried out processed, and more makes the raw material that sustained release fertilizer provides high nutrient.
The technical solution adopted in the present invention is as follows:
A kind of sludge dewatering conditioning and the method for making the sustained release fertilizer raw material, described method specifically may further comprise the steps:
A, in every cubic metre of dewatered sludge, add the material conditioning mud of following weight: water-absorbent clay mineral 20-100kg, plant slag 100-300kg, compost fermentation 10-15 days;
B, add the material 50-100kg of phosphorous acid group and ammonium ion in tunning, mixing was placed 2-3 days, and mixing was placed 2-3 days;
C, adding contain magnesium alkaline matter 5-20kg, and mixing was placed 2-3 days again.
In the steps A, also be included in the step that adds absorbent polymer compound 1-5kg in every cubic metre of dewatered sludge.
The water-absorbent clay mineral is one or both combinations in attapulgite, sodium bentonite, calcium-base bentonite or organobentonite, the polynite.
The plant slag is one or both combinations in tealeaf residue, oil tea pomace, oven dry jam slag, tobacco end, beer slag, manioc waste, the pineapple processing waste residue.
Containing the magnesium alkaline matter, is one or both combinations of magnesium oxide, magnesiumcarbonate or mineral powder of magnesite, ground dolomite.
The material of phosphorous acid group and ammonium ion is monoammonium phosphate or diammonium phosphate chemical fertilizer, or a kind of in the following compounds: ammonium hydrogen phosphate, primary ammonium phosphate, triammonium phosphate.
The absorbent polymer compound is a kind of in carboxymethyl starch, the carboxymethyl cellulose.
The concrete grammar that steps A adopted is that the circulated layered mode that adds fashionable mixture with one deck mud, a layer absorbent clay mineral and absorbent polymer compound, one deck plant slag, one deck mud is added.
If the material of phosphorous acid group wherein and ammonium ion is the material of phosphorous acid group and ammonium ion, then add bicarbonate of ammonia and phosphoric acid calcium dihydrogen fertilizer among the step B respectively.
Compared with the prior art, the present invention has following technical superiority:
The method uniqueness of conditioning compost material moisture: conventional compost adopts a large amount of dewatered sludges or organism siccative, is adjusted to the required moisture content of compost, further reduces the moisture content of windrow again by the high temperature (60-70 ℃) that produces in the composting process.The present invention adopts the method for double conditioning moisture on the basis of adopting the organism siccative: the first adds water-absorbent clay mineral and absorbent polymer compound, relies on the powerful suction force of material, reduces the free-water and the water of constitution of mud.It two is to add compound or the material contain magnesium alkaline matter and phosphorous acid group and ammonium ion, produces the material that contains high crystal water by chemical reaction, further reduces water-content.In conjunction with the high temperature water-reduction that produces in the composting fermentation process, multi-pronged, respond well again.
The material that adds can produce the effect that keeps nutrient and slowly-releasing nutrient: first water-absorbent clay mineral and absorbent polymer compound, promoted the hold facility of material to nutrient, and improve the cation exchange capacity of material and the fertilizer-preserving ability of fertilizer product.It two is compound or the material reactions that contain magnesium alkaline matter and phosphorous acid group and ammonium ion, and the material of the high crystal water of generation has the effect of slowly-releasing nutrient.
Embodiment
Be further described below in conjunction with the method for specific embodiment a kind of sludge dewatering conditioning of the present invention and making sustained release fertilizer raw material.
Embodiment 1:
Mud (moisture about 80%), water-absorbent clay mineral, plant slag are pressed 1: 0.3: 1 mixed of dry weight ratio, aerobic compost method compost routinely, wherein the water-absorbent clay mineral adopts sodium bentonite, attapulgite respectively, and the plant slag adopts tealeaf residue, tobacco end, pineapple processing waste residue respectively.At compost period detecting heap temperature, measure moisture, organic matter, the N-P-K content of piling body after 15-20 days in fermentation, test-results sees Table 1:
Moisture and N-P-K content are relatively after the mixed fermentation of table 1 different material
Embodiment 2:
The mixed (table 2) that mud (moisture about 80%), calcium-base bentonite, manioc waste or pineapple processing waste residue are pressed dry weight ratio 1: 0.1-0.5: 0.5-1.0, aerobic compost method compost routinely.At compost period detecting heap temperature, measure moisture, organic matter, the N-P-K content of heap body after 15-20 days in fermentation.Test-results shows that mixing all can reach good effect according to the above ratio.
Table 2 different mixing proportion compares compost moisture and N-P-K content
Embodiment 3
Mud (moisture about 80%), water-absorbent clay mineral, pineapple bran are pressed 1: 0.3: 1 mixed of dry weight ratio, the body cooling is piled in fermentation after 15-20 days after, contain the magnesium alkaline matter in the ratio in the table 3 (in the ratio of mud dry matter and unclassified stores) adding, the compound of phosphorous acid group and ammonium ion or material and absorbent polymer compound are nursed one's health, and mix the back and measure moisture, N-P-K content.
The different amendments of table 3 are to the influence of compost moisture and nutrient
Embodiment 4:
Mud (moisture about 80%) 5m
3Adding attapulgite or each 250kg of sodium bentonite, beer slag 1000kg mixes, mode with one deck mud, one deck attapulgite or sodium bentonite, one deck beer slag is added, the body cooling is piled in fermentation after 15-20 days after, add monoammonium phosphate 375kg and carboxymethyl cellulose 15kg, add magnesium oxide 50kg mixing, placed again 2-3 days.Add urea 155kg, Repone K 264kg makes 2100kg powdered compound organic and inorganic fertilizer (containing N12%, P2O56%, K2O 8%, organic 27%).
With cabbage heart and eucalyptus is test materials, and following comparison is set: 1, compound organic and inorganic fertilizer (cabbage heart 70kg/ mu/make, eucalyptus 0.4kg/ strain/make) 2, mix fertile (urea, calcium superphosphate, Repone K) with the simple substance of application quantity of nitrogen phosphorus potassium such as 1; 3, local fertilising: vegetables are 40kg/ mu/make import composite fertilizer (15-15-15), and eucalyptus is 0.25kg/ strain/year import composite fertilizer (15-15-15); 4,1 decrement 20%.Vegetables test each sub-district agricultural output harvesting time, sampling determination harvesting part soluble sugar, vitamins C and heavy metal content.Gather and respectively handle the soil test heavy metal content.The eucalyptus test is measured after 2 years and is respectively handled all stems of eucalyptus, adds the year end to survey the eucalyptus height.
Table 4 cabbage heart test-results
Table 5 eucalyptus test-results
Can find out from the test-results of table 4 and table 5: the compound organic and inorganic fertilizer of making by above-mentioned steps mixes fertile and local fertilising (executing import fertilizer) at the simple substance that the application effect of cabbage heart and eucalyptus such as is better than at nutrient.But its effect all is better than local fertilising even decrement 20% is used all.
In the above-described embodiments, with moisture content (%), organic content (%), N-P-K content (%) represent to nurse one's health or composting after effect, and the compost product that adopts stimulation ratio (%), soluble sugar content (% fresh weight) expression to use to relate among the embodiment is for the effect of yield and quality.
Above-described embodiment, the present invention embodiment a kind of more preferably just, the common variation that those skilled in the art carries out in the technical solution of the present invention scope and replacing all should be included in protection scope of the present invention.
Claims (9)
1. the sludge dewatering conditioning and the method for making the sustained release fertilizer raw material is characterized in that described method specifically may further comprise the steps:
A, add water-absorbent clay mineral 20-100kg in every cubic metre of dewatered sludge, plant slag 100-300kg compost fermentation 10-15 days, forms tunning;
B, add the material 50-100kg of phosphorous acid group and ammonium ion in tunning, mixing was placed 2-3 days, and mixing was placed 2-3 days;
C, adding contain magnesium alkaline matter 5-20kg, and mixing was placed 2-3 days again.
2. a kind of sludge dewatering conditioning according to claim 1 and the method for making the sustained release fertilizer raw material is characterized in that, in the described steps A, also are included in the step that adds absorbent polymer compound 1-5kg in every cubic metre of dewatered sludge.
3. a kind of sludge dewatering conditioning according to claim 1 and 2 and the method for making the sustained release fertilizer raw material, it is characterized in that water-absorbent clay mineral wherein is one or both combinations in attapulgite, sodium bentonite, calcium-base bentonite or organobentonite, the polynite.
4. a kind of sludge dewatering conditioning according to claim 1 and 2 and the method for making the sustained release fertilizer raw material, it is characterized in that plant slag wherein is one or both combinations in tealeaf residue, oil tea pomace, oven dry jam slag, tobacco end, beer slag, manioc waste, the pineapple processing waste residue.
5. a kind of sludge dewatering conditioning according to claim 1 and 2 and the method for making the sustained release fertilizer raw material is characterized in that, wherein contain the magnesium alkaline matter, are one or both combinations of magnesium oxide, magnesiumcarbonate or mineral powder of magnesite, ground dolomite.
6. a kind of sludge dewatering conditioning according to claim 1 and 2 and the method for making the sustained release fertilizer raw material, it is characterized in that, the phosphorous acid group wherein and the material of ammonium ion, be monoammonium phosphate or diammonium phosphate chemical fertilizer, or a kind of in the following compounds: ammonium hydrogen phosphate, primary ammonium phosphate, triammonium phosphate.
7. a kind of sludge dewatering conditioning according to claim 2 and the method for making the sustained release fertilizer raw material is characterized in that, described absorbent polymer compound is a kind of in carboxymethyl starch, the carboxymethyl cellulose.
8. a kind of sludge dewatering conditioning according to claim 2 and the method for making the sustained release fertilizer raw material, it is characterized in that the concrete grammar that described steps A adopted is that the circulated layered mode that adds fashionable mixture with one deck mud, a layer absorbent clay mineral and absorbent polymer compound, one deck plant slag, one deck mud is added.
9. a kind of sludge dewatering conditioning according to claim 1 and 2 and the method for making the sustained release fertilizer raw material, it is characterized in that, if the material of phosphorous acid group wherein and ammonium ion is the material of phosphorous acid group and ammonium ion, then add bicarbonate of ammonia and phosphoric acid calcium dihydrogen fertilizer among the step B respectively.
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| CN2011100248465A CN102180581B (en) | 2011-01-24 | 2011-01-24 | Method for dehydrating and conditioning sludge and preparing raw materials of slow-release fertilizer |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102826935A (en) * | 2012-07-31 | 2012-12-19 | 马鞍山科邦生态肥有限公司 | Special base fertilizer for spring corn and preparation method thereof |
| CN103183540A (en) * | 2011-12-31 | 2013-07-03 | 中粮集团有限公司 | Biological organic fertilizer and preparation method thereof |
| CN103183539A (en) * | 2011-12-31 | 2013-07-03 | 中粮集团有限公司 | Dehydrating agent, preparation method thereof, organic fertilizer and preparation method thereof |
| CN103242101A (en) * | 2013-05-21 | 2013-08-14 | 湖南农业大学 | Red-mud-based nitrogen phosphorus controlled release agent and preparation method thereof |
| CN103922863A (en) * | 2014-05-07 | 2014-07-16 | 娄志 | Fertilizer adhesive |
| CN105152717A (en) * | 2015-09-15 | 2015-12-16 | 广州市净水有限公司 | Sludge converted fertilizer for use in gardens and preparation method thereof |
| CN105417929A (en) * | 2015-12-29 | 2016-03-23 | 哈尔滨工业大学 | Green sludge deep dehydrating agent and applications in compost |
| CN108358412A (en) * | 2018-04-02 | 2018-08-03 | 陈鹏 | A kind of paper mill sludge treatment agent and its preparation method and application |
| CN111747621A (en) * | 2020-05-28 | 2020-10-09 | 武汉天源环保股份有限公司 | Landfill leachate curing treatment method and landfill leachate curing treatment device |
| CN114452585A (en) * | 2021-12-29 | 2022-05-10 | 武汉大学(肇庆)资源与环境技术研究院 | Method for passivating metals in electrolytic manganese slag |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103183540B (en) * | 2011-12-31 | 2014-12-17 | 中粮集团有限公司 | Biological organic fertilizer and preparation method thereof |
| CN103183540A (en) * | 2011-12-31 | 2013-07-03 | 中粮集团有限公司 | Biological organic fertilizer and preparation method thereof |
| CN103183539A (en) * | 2011-12-31 | 2013-07-03 | 中粮集团有限公司 | Dehydrating agent, preparation method thereof, organic fertilizer and preparation method thereof |
| CN102826935A (en) * | 2012-07-31 | 2012-12-19 | 马鞍山科邦生态肥有限公司 | Special base fertilizer for spring corn and preparation method thereof |
| CN103242101A (en) * | 2013-05-21 | 2013-08-14 | 湖南农业大学 | Red-mud-based nitrogen phosphorus controlled release agent and preparation method thereof |
| CN103242101B (en) * | 2013-05-21 | 2014-09-10 | 湖南农业大学 | Red-mud-based nitrogen phosphorus controlled release agent and preparation method thereof |
| CN103922863A (en) * | 2014-05-07 | 2014-07-16 | 娄志 | Fertilizer adhesive |
| CN103922863B (en) * | 2014-05-07 | 2015-07-08 | 娄志 | Fertilizer adhesive |
| CN105152717A (en) * | 2015-09-15 | 2015-12-16 | 广州市净水有限公司 | Sludge converted fertilizer for use in gardens and preparation method thereof |
| CN105417929A (en) * | 2015-12-29 | 2016-03-23 | 哈尔滨工业大学 | Green sludge deep dehydrating agent and applications in compost |
| CN108358412A (en) * | 2018-04-02 | 2018-08-03 | 陈鹏 | A kind of paper mill sludge treatment agent and its preparation method and application |
| CN111747621A (en) * | 2020-05-28 | 2020-10-09 | 武汉天源环保股份有限公司 | Landfill leachate curing treatment method and landfill leachate curing treatment device |
| CN114452585A (en) * | 2021-12-29 | 2022-05-10 | 武汉大学(肇庆)资源与环境技术研究院 | Method for passivating metals in electrolytic manganese slag |
| CN114452585B (en) * | 2021-12-29 | 2023-09-05 | 武汉大学(肇庆)资源与环境技术研究院 | Method for passivating metal in electrolytic manganese slag |
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| CN102180581B (en) | 2013-10-09 |
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Address after: 510640 Guangdong city of Guangzhou province Tianhe District five road, SFI. Patentee after: Agricultural Resources and Environment Institute of Guangdong Academy of Agricultural Sciences Address before: 510640 Guangdong city of Guangzhou province Tianhe District five road, SFI. Patentee before: Inst. of Soil & Fertilizer, Guangdong Prov. Academy of Agricultural Science |