CN102491729B - Method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water - Google Patents
Method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water Download PDFInfo
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- CN102491729B CN102491729B CN2011103565185A CN201110356518A CN102491729B CN 102491729 B CN102491729 B CN 102491729B CN 2011103565185 A CN2011103565185 A CN 2011103565185A CN 201110356518 A CN201110356518 A CN 201110356518A CN 102491729 B CN102491729 B CN 102491729B
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Abstract
The invention provides a method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water, and belongs to the technical field of micro-polluted water pretreatment. The ceramsite is prepared from water supply factory dehydrated sludge, modified zeolite powder and a pore-forming agent according to a certain proportion by the following method which comprises the following steps of: drying, smashing and sieving the water supply factory dehydrated sludge to obtain dry sludge; smashing, sieving and calcining natural zeolite powder, and moidifying the natural zeolite powder by sodium chloride to obtain the modified zeolite powder; uniformly mixing 50 to 60 percent of the dry sludge, 35 to 49 percent of the modified zeolite powder and 1 to 5 percent of the pore-forming agent, and granulating the mixture on a granulating machine to form balls, and thus obtaining raw materials of which the particle sizes are 2 to 7 millimeters; drying and roasting the raw materials to obtain sintered ceramsite; and naturally cooling the sintered ceramsite to room temperature, and screening to obtain the ceramsite finished product. The surface of the ceramsite prepared by using the method is rough; the ceramsite has multiple apertures; and the ceramsite is used for pretreating the micro-polluted aquatic growths to forcibly remove ammonia, nitrogen and organic matters.
Description
Technical field
The invention belongs to micro-polluted water preconditioning technique field, be specifically related to the preparation method for the pretreated zeolite feedwater of micro-polluted water sludge ceramsite.
Background technology
In recent years, along with the high speed development of industry, the quickening of urbanization process and the increase of agrochemicals kind and quantity, drinking water source, the most of cities and towns of China has been subject to pollution in various degree, majority has changed micro polluted source into, and the pollutent such as organism, ammonia nitrogen surpasses the standard of surface water environment quality III class water body in the water.Traditional handling technology of water supply coagulation-precipitation-filtration-sterilization is not only limited to organism in the micro polluted source and ammonia nitrogen removal effect, and also can occur in the treating processes endangering larger Chlorination Disinfection By-products, be difficult to reach the GB5749-2006 national drinking water standard.Studies show that, add that before traditional handling technology of water supply Biological Pretreatment Techniques is economy, the effective ways that solve dissolved organic matter and ammonia nitrogen in the micro polluted source.
In giving water treatment, Biological Pretreatment Techniques mostly adopts biomembrance process, and biofilter material is its core position.Common filtrate mainly contains haydite, plastic filler, soft-filler, combined stuffing etc. at present.Haydite is ripe, the most the most frequently used Biological Pretreatment filler.And conventional leca mainly is to rely on the physiological activity of the microorganism of growth on it to come organism and ammonia nitrogen in the degradation water, and when temperature was low, microbial activities weakened, and treatment effect is undesirable.
Zeolite is the general name that is the porousness hydrous alumino silicates crystal of frame shape structure, because its inside exists a lot of uniform micropores and passage and links each other, makes zeolite have huge surface-area, becomes the good carrier of microorganism growth.On the other hand, the huge active surface of zeolite makes it have powerful London force, and the positively charged ion that distributes in the zeolite hole and part frame oxygen have the mutual balance of negative charge, thereby forms powerful electric field around ion, so zeolite has again electrostatic force.The adding and cause the adsorptive power of zeolite strong especially of London force and electrostatic force, because the existence of electrostatic force, so that zeolite has preferential selection adsorption to polarity, unsaturated, easy polar molecule.Therefore, zeolite has stronger ion-exchange and absorption property to ammonia nitrogen in the water and polar organic matter pollutent.For taking full advantage of zeolite ammonia nitrogen and organism being had good absorption property, is again the good carrier of biological growth simultaneously, and natural zeolite has been used in the biology and processing of micro-polluted source water as filler after pulverizing appropriate particle size.But because the zeolite after pulverizing mostly is irregular granular, voidage is inhomogeneous, the large place of voidage, and aeration rate is too many, the place that voidage is little, aeration rate is too little, even produces anaerobic environment, and these all exert an influence to treatment effect.
Waterworks sludge results from the production process of city tap-water, be carried out rubbish mainly as waste at present and fill up processing, this had both increased the production cost of water supply plant, had taken again a large amount of land resources, so the resource utilization problem values of waterworks sludge must be inquired into.Because its composition and conventional clay-phase seemingly, have the investigator to use to sewage sludge and replace clay to produce haydite, but institute's haydite of producing are multiplex in the strong concrete making, thereby be used as material of construction.Haydite as material of construction, mainly emphasize the intensity of haydite, and the haydite that the micro-polluted source water Biological Pretreatment is used, except need satisfy certain intensity, also need surface irregularity, certain aperture is arranged, be conducive to biomembranous growth, therefore exist obviously different from haydite for building at product requirement and making method.Chinese patent application CN101955347 discloses " manufacture method of zeolite-glass porous light material ", and utilizing natural zeolite, cullet, waterworks sludge etc. is the main material production porous material.On the one hand, the porous material that this patent is produced is that thickness is the rectangular parallelepiped of 2cm, is not suitable for as microorganism carrier; On the other hand, this patent uses natural zeolite as raw material, because the natural zeolite endoporus is stopped up by plurality of impurities, absorption property is very limited.Up to now, also do not utilize waterworks sludge, modified zeolite powder etc. to make the report that is used for micro-polluted source water Biological Pretreatment haydite as basic raw material.
Summary of the invention
Above technical problem for the prior art existence, for strong absorption property and the biological oxidation of zeolite to ammonia nitrogen and polar organic matter combined, the problem of ammonia nitrogen and organic matter removal effect and solution waterworks sludge resource utilization in the reinforcement micro-polluted source water, the invention provides a kind ofly take water supply plant dewatered sludge, modified zeolite powder etc. as main raw material, add pore-forming material and fire the micro-polluted water Biological Pretreatment that forms with zeolite based feedwater sludge ceramsite and preparation method.
Preparation method's for the pretreated zeolite of micro-polluted water feedwater sludge ceramsite provided by the present invention concrete steps are as follows:
(1) preparation feedwater dewatered sludge: with the dewatered sludge of water supply plant water ratio 80wt%, at 105 ~ 110 ℃ of dry 2h, obtain the feedwater dewatered sludge of water ratio 52 wt%, then described feedwater dewatered sludge is pulverized in pulverizer, cross 80 mesh sieves, obtain particle diameter less than the Powdered feedwater dewatered sludge of 80 purposes;
(2) preparation modified zeolite powder: natural zeolite is pulverized with pulverizer, cross 80 mesh sieves, zeolite powder after sieving is put in the retort furnace roasting 2h under 350 ℃ of conditions, be cooled to after the room temperature in the adsorption column that zeolite powder packed into, then the sodium chloride solution with 1mol/L passes through described adsorption column with the flow velocity following current of 0.25m/h, after 10 times of sodium chloride solutions to the 1mol/L of zeolite volume pass through described adsorption column, modified active finishes, zeolite behind the taking-up modified active, in air dry oven, under 105 ~ 110 ℃ of conditions, obtain modified zeolite powder behind the dry 2h;
(3) raw material mixes: the Powdered feedwater dewatered sludge that step (1) is made, modified zeolite powder and the pore-forming material sodium bicarbonate that step (2) makes are respectively according to mass percent: 50 ~ 60%, 35 ~ 49% and 1 ~ 5% ratio, join to mix and mix 30min in the still, make compound;
(4) balling-up: the prepared compound of step (3) is transferred in the tumbling disk granulator, adds the laggard row granulation of entry, the quality that adds entry is 5% of described mixture quality, obtains particle diameter at the spherical raw material of 2 ~ 7mm;
(5) spherical raw material pre-treatment: the prepared spherical raw material of step (4) are put into air dry oven, and under 105 ~ 110 ℃ of conditions, dry 60min obtains the oven dry material;
(6) roasting: the prepared oven dry material of step (5) is put into retort furnace, setting the retort furnace temperature rise rate is 5 ℃/min, constant temperature calcining 30min after muffle furnace is raised to 1000 ℃ gradually from room temperature obtains the haydite after the roasting, then naturally cools to room temperature;
(7) the prepared haydite of step (6) is sieved, remove substandard product, obtain the haydite finished product of different-grain diameter.
The present invention compares with leca with the water treatment of routine and has the following advantages:
(1) the present invention replaces conventional clay to make haydite with the water supply plant dewatered sludge, both waterworks sludge has been carried out recycling, has protected again clay resource.
(2) because zeolite has a lot of holes and passage, and prepared filter material surface roughness and the specific surface area of the present invention all is significantly increased, be used for the micro-polluted source water Biological Pretreatment Techniques, be conducive to the biofilm growth of microorganism.
(3) because the introducing of zeolite, the prepared haydite of this invention is used for the micro-polluted water Biological Pretreatment, absorption and the biological degradation of zeolite are combined, ammonia nitrogen and organic matter removal have greatly been promoted, especially larger to the raising of ammonia nitrogen removal effect, the ability of anti-ammonia nitrogen impact load obviously strengthens.
Embodiment
Each raw materials quality is composed as follows among the embodiment 1-3 that present embodiment provides:
The feedwater dewatered sludge of embodiment 1:60%, 35% modified zeolite powder and 5% pore-forming material sodium bicarbonate.
The feedwater dewatered sludge of embodiment 2:50%, 49% modified zeolite powder and 1% pore-forming material sodium bicarbonate.
The feedwater dewatered sludge of embodiment 3:55%, 42% modified zeolite powder and 3% pore-forming material sodium bicarbonate.
Concrete preparation process is as follows:
(1) preparation feedwater dewatered sludge: with the dewatered sludge of water supply plant water ratio 80wt%, at 105 ~ 110 ℃ of dry 2h, obtain the feedwater dewatered sludge of water ratio 52 wt%, then described feedwater dewatered sludge is pulverized in pulverizer, cross 80 mesh sieves, obtain Powdered feedwater dewatered sludge;
(2) preparation modified zeolite powder: natural zeolite is pulverized with pulverizer, cross 80 mesh sieves, zeolite powder after sieving is put in the retort furnace roasting 2h under 350 ℃ of conditions, be cooled to after the room temperature in the adsorption column that zeolite powder packed into, then the sodium chloride solution with 1mol/L passes through described adsorption column with the flow velocity following current of 0.25m/h, after 10 times of sodium chloride solutions to the 1mol/L of zeolite volume pass through described adsorption column, modified active finishes, zeolite behind the taking-up modified active, in air dry oven, under 105 ~ 110 ℃ of conditions, obtain modified zeolite powder behind the dry 2h;
(3) raw material mixes: the Powdered feedwater dewatered sludge that step (1) is made, the modified zeolite powder that step (2) makes and pore-forming material sodium bicarbonate join to mix and mix 30min in the still, make compound;
(4) balling-up: the prepared compound of step (3) is transferred in the tumbling disk granulator, adds the laggard row granulation of entry, the quality that adds entry is 5% of described mixture quality, obtains particle diameter at the spherical raw material of 2 ~ 7mm;
(5) spherical raw material pre-treatment: the prepared spherical raw material of step (4) are put into air dry oven, and under 105 ~ 110 ℃ of conditions, dry 60min obtains the oven dry material;
(6) roasting: the prepared oven dry material of step (5) is put into retort furnace, setting the retort furnace temperature rise rate is 5 ℃/min, constant temperature calcining 30min after muffle furnace is raised to 1000 ℃ gradually from room temperature obtains the haydite after the roasting, then naturally cools to room temperature;
(7) the prepared haydite of step (6) is sieved, remove substandard product, obtain the haydite finished product of different-grain diameter.
The prepared haydite of embodiment 1-3 all meets the relevant regulations of " the artificial ceramic grain filter of water treatment ".
Claims (1)
1. be used for the preparation method of the pretreated zeolite feedwater of micro-polluted water sludge ceramsite, it is characterized in that these preparation method's concrete steps are as follows:
(1) preparation feedwater dewatered sludge: with the dewatered sludge of water supply plant water ratio 80wt%, at 105 ~ 110 ℃ of dry 2h, obtain the feedwater dewatered sludge of water ratio 52 wt%, then described feedwater dewatered sludge is pulverized in pulverizer, cross 80 mesh sieves, obtain particle diameter less than the Powdered feedwater dewatered sludge of 80 purposes;
(2) preparation modified zeolite powder: natural zeolite is pulverized with pulverizer, cross 80 mesh sieves, zeolite powder after sieving is put in the retort furnace roasting 2h under 350 ℃ of conditions, be cooled to after the room temperature in the adsorption column that zeolite powder packed into, then the sodium chloride solution with 1mol/L passes through described adsorption column with the flow velocity following current of 0.25m/h, after 10 times of sodium chloride solutions to the 1mol/L of zeolite volume pass through described adsorption column, modified active finishes, zeolite behind the taking-up modified active, in air dry oven, under 105 ~ 110 ℃ of conditions, obtain modified zeolite powder behind the dry 2h;
(3) raw material mixes: the Powdered feedwater dewatered sludge that step (1) is made, modified zeolite powder and the pore-forming material sodium bicarbonate that step (2) makes are respectively according to mass percent: 50 ~ 60%, 35 ~ 49% and 1 ~ 5% ratio, join to mix and mix 30min in the still, make compound;
(4) balling-up: the prepared compound of step (3) is transferred in the tumbling disk granulator, adds the laggard row granulation of entry, the quality that adds entry is 5% of described mixture quality, obtains particle diameter at the spherical raw material of 2 ~ 7mm;
(5) spherical raw material pre-treatment: the prepared spherical raw material of step (4) are put into air dry oven, and under 105 ~ 110 ℃ of conditions, dry 60min obtains the oven dry material;
(6) roasting: the prepared oven dry material of step (5) is put into retort furnace, setting the retort furnace temperature rise rate is 5 ℃/min, constant temperature calcining 30min after muffle furnace is raised to 1000 ℃ gradually from room temperature obtains the haydite after the roasting, then naturally cools to room temperature;
(7) the prepared haydite of step (6) is sieved, remove substandard product, obtain the haydite finished product of different-grain diameter.
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| CN2011103565185A CN102491729B (en) | 2011-11-11 | 2011-11-11 | Method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water |
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| CN2011103565185A CN102491729B (en) | 2011-11-11 | 2011-11-11 | Method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water |
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| CN103028384A (en) * | 2012-12-03 | 2013-04-10 | 姜英杰 | Preparation method of high-capacity fluorion adsorbent |
| CN103991971B (en) * | 2014-05-30 | 2016-01-20 | 东北大学 | A kind of irrigation canals and ditches matrix and compound method thereof hindering ammonia nitrogen in control rice field water-break |
| CN105130391B (en) * | 2015-07-10 | 2017-11-17 | 武汉理工大学 | The method for preparing light ceramic using bottom mud in lake and municipal sludge microwave sintering |
| CN106076252A (en) * | 2016-06-15 | 2016-11-09 | 北京建筑大学 | A kind of method utilizing waterworks sludge preparation denitrogenation dephosphorizing adsorbent simultaneously |
| CN110721662A (en) * | 2019-10-30 | 2020-01-24 | 安徽工业大学 | Preparation method and recovery method of modified zeolite powder for simultaneously removing natural organic matters and ammonia nitrogen in slightly polluted water |
| CN111087199A (en) * | 2019-12-20 | 2020-05-01 | 南通斐腾新材料科技有限公司 | Preparation method of porous hollow zeolite particles for adsorbing VOCs (volatile organic compounds) |
| CN112174294A (en) * | 2020-08-28 | 2021-01-05 | 江苏河清海晏环境有限公司 | Preparation method of composite filler for advanced sewage treatment |
| CN112844304A (en) * | 2021-02-05 | 2021-05-28 | 苏州科技大学 | Sodium pyrophosphate modified water purification sludge/zeolite composite adsorbent and preparation method and application thereof |
| CN113402012B (en) * | 2021-06-02 | 2023-12-12 | 浙江工业大学 | Aerobic composting reinforced horizontal subsurface flow constructed wetland denitrification device and application |
| CN115608340B (en) * | 2022-10-11 | 2024-02-02 | 青岛科技大学 | Magnetic ceramsite adsorbent for removing heavy metal copper ions in water and preparation method thereof |
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Application publication date: 20120613 Assignee: Shanghai Jiang Ke Industrial Equipment Co., Ltd. Assignor: Ding Meihua Contract record no.: 2015310000022 Denomination of invention: Method for preparing zeolite water-supply sludge ceramsite for pretreating micro-polluted water Granted publication date: 20130403 License type: Exclusive License Record date: 20150213 |