CN105126753B - A kind of method that utilization debirs prepare activity adsorbing carbon material - Google Patents
A kind of method that utilization debirs prepare activity adsorbing carbon material Download PDFInfo
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- CN105126753B CN105126753B CN201510527173.3A CN201510527173A CN105126753B CN 105126753 B CN105126753 B CN 105126753B CN 201510527173 A CN201510527173 A CN 201510527173A CN 105126753 B CN105126753 B CN 105126753B
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Abstract
The invention provides a kind of method that utilization debirs prepare activity adsorbing carbon material, it is characterised in that including：The first step：Debirs are modified pretreatment, obtain preparing the raw material of adsorbent charcoal；Second step：After the described raw material dehydration for preparing adsorbent charcoal, add in catalyst, injection closed reactor, according to the reaction that imposes a condition；3rd step：After reaction terminates, reaction system is cooled down, the mixture obtained by reaction is post-processed, adsorbent charcoal is obtained.The present invention is using the kitchen garbage based on excess sludge and carbohydrate containing containing the municipal sewage plant based on protein, and the federated resourceization for realizing a variety of debirs is utilized；Present invention adds a variety of catalytic species, the crystallinity of adsorbent charcoal is optimized, its absorption property to dyestuff is obviously improved.Preparation process of the present invention is simple, and reaction condition is gentle.
Description
Technical field
The invention belongs to technical field of environmental pollution treatment, the resource utilization method of two kinds of debirs is related generally to.
Background technology
Though organic solid waste refers in production, life and other activities the original value of forfeiture that produces or not
Value but the solid-state organic article and material being abandoned or abandon are lost, it is mainly characterized by carbohydrate (egg
White matter, polysaccharide, fat) content is big, and recycling value is high.Such as：Municipal sewage plant produces substantial amounts of excess sludge
Containing a large amount of protein；Catering trade and the kitchen garbage of the daily generation of people contain a large amount of carbohydrate.Recycling debirs have
There are very important realistic meaning and economic society value, meet the theory of sustainable development.At traditional debirs processing
Putting scheme includes burning, landfill etc., although serves minimizing and innoxious effect, but wastes the limited organic carbon of the mankind
Source.These debirs are both pollutant and a kind of resource, and numerous studies are concerned with how that recycling reclaims organic acid (such as：One
The method ZL201010524770.8 for planting recycling sludge).
Debirs are prepared into other functional materials for another recycling thinking, such as adsorbent, fuel (Wang Ding
U.S., Wang Yueqiang waits hydro-thermal charings to prepare the carbon fixation Journal of Chemical Industry and Engineering of sludge organism charcoal, 2013,64 (7)：2625~2632).
The method that existing debirs prepare sorbing material is also rested on using the simple hydro-thermal process of single waste progress, there is carbon
Material carbonizing degree is low, and carbon structure is unformed, and porosity is low and the problems such as microcellular structure heterogeneity, although obtained by metal-modified
The carbon material obtained overcomes the low problem of carbon material porosity to a certain extent, such as (Wu Qianfang, Wu Jianzhi, Zhang Fushen hydro-thermal charcoals
Change kitchen garbage and prepare Nanoscale Iron/carbon composite environmental project journals, 2013,7 (2)：695~700), but absorption property is still
So have much room for improvement.
Its space structure of single protein and carbohydrate is different, carbon skeleton structure after being reacted under certain temperature and pressure
As difference；The space conformation of homogenization be easily caused carbon material adsorption efficiency decline, be easily saturated, microcellular structure homoplasy it is strong.
In order to overcome this problem, the present invention introduces active catalyst, by the organic carbon of different structure using compound organic waste materials
Source coupled reaction, collaboration promotes the absorption property of carbon material.
The content of the invention
In view of the shortcomings of the prior art, activity adsorbing carbon material is prepared it is an object of the invention to provide a kind of utilization debirs
Method, the federated resourceization that the method achieve debirs is utilized, and adds multiple catalysts to being modified at charcoal optimization.
In order to achieve the above object, the invention provides a kind of method that utilization debirs prepare activity adsorbing carbon material, its
It is characterised by, including：
The first step：Debirs are modified pretreatment, obtain preparing the raw material of adsorbent charcoal；
Second step：After the described raw material dehydration for preparing adsorbent charcoal, add in catalyst, injection closed reactor, press
According to the reaction that imposes a condition；
3rd step：After reaction terminates, reaction system is cooled down, the mixture obtained by reaction is post-processed, adsorbed
Charcoal.
Preferably, the debirs in the described first step include the excess sludge and kitchen rubbish of municipal sewage plant
Rubbish, the moisture content of the excess sludge of described municipal sewage plant is 65%~98%, TOC (VSS) is 5~
450g/L, the moisture content of described kitchen garbage is 30%~80%, and TOC is 10~350g/L.
It is highly preferred that the modification pretreatment in the described first step includes：Kitchen garbage is rejected after inorganic matter block, used
Crusher in crushing to particle diameter is below 2mm, by the excess sludge and kitchen garbage of municipal sewage plant according to organic matter dry weight
Ratio mixing than 0.1: 1~10: 1, organic matter total content is 10~80g/L after mixing；Stirring, 0.01 is added at 30~80 DEG C
~0.5mL/g VSS HCl solution or H2SO4 solution, obtains preparing the raw material of adsorbent charcoal.
It is highly preferred that the concentration of described HCl solution is more than 36%, the concentration of described H2SO4 solution for 98% with
On.
Preferably, in described second step, solid content reaches more than 65% after dehydration, and the method for dehydration is centrifugation, press filtration
Or vacuum filtration, wherein, centrifugation uses centrifugal concentrator, centrifuges 5~15min, and rotating speed is 200~1500rpm, and press filtration uses 4 μ
M apertures nonwoven filtration cloth, pressure≤0.6MPa, vacuum filtration pressure is 0.05MPa, 3~5min of suction filtration.
Preferably, the catalyst in described second step includes hydrogen peroxide, reproducibility iron powder, CoCl2 and FeCl3, described
The addition of hydrogen peroxide be 0.1~1mL/g VSS, the addition of reproducibility iron powder, CoCl2 and FeCl3 is respectively 0.1~
0.3g/g VSS, 0.08~0.1g/g VSS and 0.04~0.07g/g VSS.
It is highly preferred that the concentration of described hydrogen peroxide is 25%-35%.
Preferably, described closed reactor is heatproof, pressure-resistant closed reactor, is internally provided with lining.
It is highly preferred that described closed reactor is 280 DEG C of heatproof, pressure-resistant 5MPa closed reactor, described lining
For tetrafluoroethene or PPL.
Preferably, the reaction condition in described second step is：The temperature of reaction system is set to be raised to 180 in 0.5-1.5h
~250 DEG C, and temperature 0.5-1.5h is kept, pressure is 1~1.5MPa, and mixing speed is 800rpm.
Preferably, described post-processing approach is：Take out liquid and add absolute ethyl alcohol, 3~20h is shaken in shaking table, will
Liquid suction filtration after concussion, obtains solid, and is constantly rinsed with water, until cleaning liquid is colourless, obtained solid product is placed on
Thermostatic drying chamber is taken out drying solid and grinds standby, obtained adsorbent charcoal with 30~85 DEG C of dry 2~24h.
Compared with prior art, the beneficial effects of the invention are as follows：
(1) present invention is using based on excess sludge and carbohydrate containing containing the municipal sewage plant based on protein
Kitchen garbage, realize a variety of debirs federated resourceization utilize；
(2) present invention adds a variety of catalytic species, the crystallinity of adsorbent charcoal is optimized, its suction to dyestuff is obviously improved
Attached performance.
(3) preparation process of the present invention is simple, and reaction condition is gentle.
Embodiment
With reference to specific embodiment, the present invention is expanded on further.It should be understood that these embodiments are merely to illustrate the present invention
Rather than limitation the scope of the present invention.In addition, it is to be understood that after the content of the invention lectured has been read, people in the art
Member can make various changes or modifications to the present invention, and these equivalent form of values equally fall within the application appended claims and limited
Scope.Closed reactor in embodiment 1-3 is 280 DEG C of heatproof, pressure-resistant 5MPa closed reactor, is internally provided with tetrafluoro
Ethene lining.
Embodiment 1
A kind of method that utilization debirs prepare activity adsorbing carbon material, be specially：
(1) excess sludge of 1L city domestic sewages treatment plant is taken, at room temperature natural sedimentation 4h, removes supernatant, obtain
Thickened sludge (moisture content 96%, TOC is 20g/L)；Taking food a kitchen garbage 0.14L, (moisture content 57%, always has
Machine matter content is 150g/L), the inorganic matter block such as plastic products, toothpick, bone in waste is rejected, Mechanical Crushing crusher machine is used
To particle diameter≤2mm.The excess sludge and kitchen garbage of municipal sewage plant are mixed according to the ratio of organic matter dry weight ratio 1: 1
Close, it is homogeneous to stir under 300rpm speed 7min using magnetic stirring apparatus, obtains mixture (moisture content 73%, total organic matter
Content 36g/L).
(2) mixture is taken, 0.36mL 37% concentrated hydrochloric acid (taking 0.01g/L VSS) is added at 35 DEG C, obtains preparing and inhales
The raw material of attached charcoal.Mixture is further dehydrated in centrifugal concentrator, and rotating speed is 1000rpm, and centrifugation time is 10min, dehydration
Solid content is 65% afterwards.
(3) above-mentioned centrifugation is obtained into solid to be put into closed reactor, adds concentration and (taken for 30% hydrogen peroxide 3.6mL
0.1mL/g VSS), reproducibility iron powder 3.6g (takes 0.1g/g VSS), CoCl22.88g (takes 0.08g/g VSS), FeCl3
1.44g (takes 0.04g/g VSS).The temperature of reaction system is raised to 180 DEG C in 1h, and keep temperature 1h, pressure is
1.2MPa, reactor need to be stirred continuously, and mixing speed is 800rpm.
(4) take out liquid and add 15mL absolute ethyl alcohols, 6h is shaken in shaking table, by the liquid suction filtration after concussion, consolidate
Body, and constantly rinsed with running water, until cleaning liquid is colourless, obtained solid product is placed on 65 DEG C of dryings of thermostatic drying chamber
10h, takes out drying solid grinding, as adsorbent charcoal.
(5) 100mL 100mg/L rhodamine B solution need to be used by examining the adsorptivity of adsorbent charcoal, add 0.1g absorption
8h is shaken under the conditions of charcoal lucifuge, the absorbance of dyestuff after original dye and processing is determined under 554nm wavelength.After measured, adsorb
Charcoal is up to 82% to the adsorptivity of rhdamine B.
Embodiment 2
A kind of method that utilization debirs prepare activity adsorbing carbon material, be specially：
(1) excess sludge of 1.5L city domestic sewages treatment plant is taken, at room temperature natural sedimentation 4h, removes supernatant, obtain
To thickened sludge (moisture content 97%, TOC is 25g/L)；Take food a kitchen garbage 0.26L (moisture content 58%, always
The content of organic matter is 145g/L), the inorganic matter block such as plastic products, toothpick, bone in waste is rejected, it is broken using mechanical crusher
It is broken to particle diameter≤2mm.Obtained sludge is mixed with kitchen garbage according to organic matter dry weight than 1: 1, magnetic agitation is used
It is homogeneous that device stirs 7min under 300rpm speed, obtains mixture (moisture content 75%, TOC 42.7g/L).
(2) mixture is taken, 0.43mL 37% concentrated hydrochloric acid (taking 0.01ml/g VSS) is added at 35 DEG C, is prepared
The raw material of adsorbent charcoal.Mixture is further dehydrated in centrifugal concentrator, and rotating speed is 1000rpm, and centrifugation time is 10min, is taken off
Solid content is 65% after water.
(3) above-mentioned centrifugation is obtained into solid to be put into closed reactor, adds concentration and (taken for 30% hydrogen peroxide 4.27mL
0.1mL/g VSS), reproducibility iron powder 4.27g (takes 0.1g/g VSS), and CoCl2 3.416g (take 0.08g/g VSS), FeCl3
1.708g (takes 0.04g/g VSS).The temperature of reaction system is raised to 180 DEG C in 1h, and keep temperature 1h, pressure is
1.2MPa, reactor need to be stirred continuously, and mixing speed is 800rpm.
(4) take out liquid and add 20mL absolute ethyl alcohols, 6h is shaken in shaking table, by the liquid suction filtration after concussion, consolidate
Body, and constantly rinsed with running water, until cleaning liquid is colourless, obtained solid product is placed on 65 DEG C of dryings of thermostatic drying chamber
12h, takes out drying solid grinding standby.
(5) 100mL 100mg/L rhodamine B solution need to be used by examining the adsorptivity of adsorbent charcoal, add 0.1g absorption
8h is shaken under the conditions of charcoal lucifuge, the absorbance of dyestuff after original dye and processing is determined under 554nm wavelength.After measured, adsorb
Charcoal is up to 85% to the adsorptivity of rhdamine B.
Embodiment 3：
A kind of method that utilization debirs prepare activity adsorbing carbon material, be specially：
(1) excess sludge of 2.5L city domestic sewages treatment plant is taken, at room temperature natural sedimentation 4h, removes supernatant, obtain
To thickened sludge (moisture content 97%, TOC is 23g/L)；Take food a kitchen garbage 0.35L (moisture content 52%, always
The content of organic matter is 165g/L), the inorganic matter block such as plastic products, toothpick, bone in waste is rejected, it is broken using mechanical crusher
It is broken to particle diameter≤2mm.Obtained sludge is mixed with kitchen garbage according to organic matter dry weight than 1: 1, magnetic agitation is used
It is homogeneous that device stirs 10min under 300rpm speed, obtains mixture (moisture content 75%, TOC 41g/L).
(2) mixture is taken, 0.41mL 37% concentrated hydrochloric acid (taking 0.01g/L VSS) is added at 35 DEG C, obtains preparing and inhales
The raw material of attached charcoal.Mixture is further dehydrated in centrifugal concentrator, and rotating speed is 1000rpm, and centrifugation time is 10min, dehydration
Solid content is 65% afterwards.
(3) above-mentioned centrifugation is obtained into solid to be put into closed reactor, it is that 30% hydrogen peroxide 4.1mL (takes to add concentration
0.1mL/g VSS), reproducibility iron powder 4.1g (takes 0.1g/g VSS), and CoCl2 3.28g (take 0.08g/g VSS), FeCl3
1.64g (takes 0.04g/g VSS).The temperature of reaction system is raised to 180 DEG C in 1h, and keep temperature 1h, pressure is
1.2MPa, reactor need to be stirred continuously, and mixing speed is 800rpm.
(4) take out liquid and add 25mL absolute ethyl alcohols, 8h is shaken in shaking table, by the liquid suction filtration after concussion, consolidate
Body, and constantly rinsed with running water, until cleaning liquid is colourless, obtained solid product is placed on 65 DEG C of dryings of thermostatic drying chamber
15h, takes out drying solid grinding standby.
(5) examine the adsorptivity of adsorbent charcoal to use 100mL 100mg/L methylene blue solution, add 0.1g adsorbent charcoal
8h is shaken under the conditions of lucifuge, the absorbance of dyestuff after original dye and processing is determined under 664nm wavelength.After measured, adsorbent charcoal
Adsorptivity to methylene blue dye is up to 84.2%.
Claims (6)
1. a kind of method that utilization debirs prepare activity adsorbing carbon material, it is characterised in that including：
The first step：Debirs are modified pretreatment, obtain preparing the raw material of adsorbent charcoal；Described debirs include city
The excess sludge and kitchen garbage of sewage treatment plant of city, the moisture content of the excess sludge of described municipal sewage plant for 65% ~
98%, TOC is 5 ~ 450g/L, and the moisture content of described kitchen garbage is 30% ~ 80%, TOC is 10 ~
350g/L；Described modification pretreatment includes：Kitchen garbage is rejected after inorganic matter block, is using crusher in crushing to particle diameter
Below 2mm, by the excess sludge and kitchen garbage of municipal sewage plant according to organic matter dry weight ratio 0.1:1~10:1 ratio
Mixing, organic matter total content is 10 ~ 80 g/L after mixing；Stirring, it is molten in 30 ~ 80 DEG C of HCl for adding 0.01 ~ 0.5 mL/g VSS
Liquid or H2SO4Solution, obtains preparing the raw material of adsorbent charcoal；
Second step：After the described raw material dehydration for preparing adsorbent charcoal, add in catalyst, injection closed reactor, according to setting
Fixed condition reacts；Described catalyst includes hydrogen peroxide, reproducibility iron powder, CoCl2And FeCl3, the addition of described hydrogen peroxide
For 0.1 ~ 1mL/g VSS, reproducibility iron powder, CoCl2And FeCl3Addition be respectively 0.1 ~ 0.3 g/g VSS, 0.08 ~ 0.1
G/g VSS and 0.04 ~ 0.07 g/g VSS；Reaction condition is：The temperature of reaction system is set to be raised to 180 ~ 250 in 0.5-1.5h
DEG C, and temperature 0.5-1.5h is kept, pressure is 1 ~ 1.5MPa, and mixing speed is 600-1000rpm；
3rd step：After reaction terminates, reaction system is cooled down, the mixture obtained by reaction is post-processed, adsorbent charcoal is obtained.
2. the method for preparing activity adsorbing carbon material using debirs as claimed in claim 1, it is characterised in that described HCl
The concentration of solution is more than 36%, described H2SO4The concentration of solution is more than 98%.
3. the method for preparing activity adsorbing carbon material using debirs as claimed in claim 1, it is characterised in that described second
In step, solid content reaches more than 65% after dehydration, and the method for dehydration is centrifugation, press filtration or vacuum filtration, wherein, centrifugation using from
Heart thickener, centrifuges 5 ~ 15min, and rotating speed is 200 ~ 1500 rpm, press filtration using 4 μm of aperture nonwoven filtration cloth, pressure≤
0.6MPa, vacuum filtration pressure is 0.05MPa, 3 ~ 5min of suction filtration.
4. the method for preparing activity adsorbing carbon material using debirs as claimed in claim 1, it is characterised in that described dioxygen
The concentration of water is 25%-35%.
5. the method for preparing activity adsorbing carbon material using debirs as claimed in claim 1, it is characterised in that described is closed
Reactor is heatproof, pressure-resistant closed reactor, is internally provided with lining.
6. the method for preparing activity adsorbing carbon material using debirs as claimed in claim 1, it is characterised in that described rear place
Reason method is：Take out liquid and add absolute ethyl alcohol, 3 ~ 20h is shaken in shaking table, by the liquid suction filtration after concussion, solid is obtained,
And constantly rinsed with water, until cleaning liquid is colourless, obtained solid product is placed on thermostatic drying chamber and dries 2 ~ 24 with 30 ~ 85 DEG C
H, takes out drying solid and grinds standby, obtain adsorbent charcoal.
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