A kind of method and system recycling guanite from sludge
Technical field
The present invention relates to technical field of sludge treatment, specially a kind of method and system recycling guanite from sludge.
Background technology
It is final that there are about 80%TP in the municipal wastewater processing procedure based on activated sludge process technology system, in municipal wastewater
It can be transferred in remaining municipal sludge.At present plate compression deep dehydration as important sludge reduction processing mode in industry
Inside be widely applied, but due in sludge dewatering filtrate phosphorus concentration it is higher, if sludge dewatering filtrate directly flowed back
It can then cause return load inside sewage treatment plant higher;In addition, diaphragm plate frame deep dehydration leading portion mostly uses lime chemistry
Medicament improves sludge, and the phosphorus element in sludge is caused to be stored in sludge solid phase more, and is not easy to be transferred in liquid phase, this just makes
The organophosphor obtained in the sludge after diaphragm plate frame deep dehydration cannot fully discharge, and the direct burning of phosphorous dewatered sludge
Or landfill stabilization can cause the waste of a large amount of phosphor resources;And since diaphragm plate frame deep dehydration leading portion uses chemical drugs
Agent causes sludge following resourceization to utilize relative difficulty, limits outlet;But if sludge does not use before sheet frame deep dehydration
Chemical agent improves, and sludge dewatering can be caused difficult, can not be effectively separated by solid-liquid separation, and it is shapeless to eventually lead to mud cake,
Influence Treatment of Sludge effect.Thus how to extract phosphorus from sludge is current Treatment of Sludge urgent problem to be solved.
Guanite, main chemical compositions MgNH4PO4·6H2O, white crystallization fine grained or powdered are a kind of high
The rock phosphate in powder of taste and a kind of fabulous slow-release fertilizer, guanite reserves are few in nature and still drop at the fast speed.When molten
Contain Mg in liquid2+, NH4+, HnPO4 n-3And ion concentration product more than guanite solubility product constant when will occur spontaneous precipitation from
And form MgNH4PO4·6H2O, reaction equation:
Mg2++PO4 3-+NH4 ++6H2O→MgNH4PO4·6H2O
Mg2++HPO4 2-+NH4 ++6H2O→MgNH4PO4·6H2O+H+
Mg2++H2PO4 3-+NH4 ++6H2O→MgNH4PO4·6H2O+2H+。
Thus occur extracting the method for guanite from sewage solution in sewage treatment field at present and recycling is reacted
Device, but it is mostly to be designed for phosphorus-containing wastewater, using continuous flow mode of operation, the flow rate of water flow that continuously rises in reactor
It is higher, easily cause fine grained guanite to be largely lost with water outlet, to influence effluent quality and phosphorus organic efficiency, and in order to protect
It holds sufficient hydraulic detention time and protection guanite generates and effect of settling, also more installations in the recycling reaction unit of guanite
There is agitating device, height height, the volume for also having led to recycling reaction unit are big, largely effect on space availability ratio, increase equipment
Investment.
Invention content
In view of the above-mentioned problems, the method that the present invention provides a kind of to recycle guanite from sludge, can solve existing dirt
In mud processing procedure phosphorus element be largely stored in solid phase and be unable to fully to discharge and extract and cause phosphor resource largely waste ask
Topic;For this purpose, the present invention also provides the systems for recycling guanite from sludge.
A method of recycling guanite from sludge, it is characterised in that:First to thickened sludge in ultrasonic reaction pot
It is ultrasonically treated, the thickened sludge after the supersound process is consolidated using diaphragm plate frame filter press while stirring then
Liquid separating treatment, obtains dehydrated sludge cake and filtrate, and the dehydrated sludge cake is transported outward and is disposed, and filter device carries out two to the filtrate
It is secondary that secondary filtrate is obtained by filtration, press Mg in guanite reacts retracting device:P molar ratios (1.3~1.5):1 ratio will be secondary
Filtrate mixes with magnesium source carries out guanite reaction treatment, and the guanite reacting treatment time control was at 2 hours, in the birds droppings
Guanite particle Precipitation out of described secondary filtrate during stone reaction treatment is collected after guanite reaction treatment and to be precipitated
The guanite particle, secondary filtrate are back to sewage treatment plant and are further processed.
Further, the acoustic density control of the supersound process is in 0.2W/mL~0.5W/mL, and ultrasonic time is 60~
90 minutes.
Further, the thickened sludge after the supersound process is carried out at separation of solid and liquid using diaphragm plate frame filter press
During reason, the control of the feed pressure of diaphragm plate frame filter press is in 1.0Mpa, and feed time control was at 1.5 hours, squeeze pressure
Control is in 1.6MPa, and at 1.0 hours, dump process was maintained at 0.5 hour squeezing time control.
Further, after the secondary filter, control the suspension content in the secondary filtrate be down to 10mg/L with
Under.
Further, when carrying out guanite reaction recycling, the reaction solution in retracting device is reacted to guanite and is carried out
Synchronous pH values monitoring, controls the pH value of reaction solution between 7.5~8.5.
A kind of system recycling guanite from sludge, it is characterised in that:It includes
Sludge concentration tank, the concentration for sludge are collected;
Sludge by Ultrasonic retort, for being ultrasonically treated to thickened sludge so that thickened sludge is broken to cause cell broken
It splits, promotes intracellular water and PO4 3-Release;
Diaphragm plate frame filter press detaches to obtain solid phase mud for being separated by solid-liquid separation to the thickened sludge after sonicated
Cake and liquid phase filtrate;
Filter device carries out secondary filter with to liquid phase filtrate, to obtain secondary filtrate;
Guanite reacts retracting device, is collected for carrying out guanite reaction to the secondary filtrate;
The discharge opening pipeline of the sludge concentration tank connects the feed inlet of the Sludge by Ultrasonic retort, the Sludge by Ultrasonic
The discharge gate pipeline of retort connects the feed inlet of the diaphragm plate frame filter press, the filtrate (liquid of the diaphragm plate frame filter press
The inlet that the guanite reacts retracting device is connected by the transition apparatus pipeline, the guanite reacts retracting device
Equipped with magnesium source adding mouth, the bottom of the guanite reaction retracting device is provided with leakage fluid dram and discharge gate valve.
Further, ultrasonic generator and agitating device are provided in the Sludge by Ultrasonic retort.
Further, guanite reaction retracting device includes tank body and external circulation return pipe, in the tank body
It is provided with top reaction zone and bottom decanting zone, the bottom decanting zone is in back taper, and the top reaction zone is settled with bottom
It is provided with liquid distribution trough between area, reactor, magnesium source adding mouth, inlet difference are installed in the top reaction zone
It is connected into the liquid distribution trough by pipeline, the top reaction zone of the tank body is provided with top circulation fluid refluxing opening and bottom
Circulation fluid import, the circulation return pipe pass through circulation pipe respectively with the top circulation fluid refluxing opening, bottom cycle liquid import
Road connects, and the bottom cycle liquid inlet ductwork is connected into the liquid distribution trough.
Further, the reactor includes hollow stainless steel reaction lining, filling in the stainless copper reaction lining
There is stainless (steel) wire.
Further, top, the bottom of the stainless steel reaction lining are respectively arranged with flow-stopping plate.
Further, the tank body of the guanite retracting device is also respectively connected with acid solution case, lye tank, and the tank body
On pH value on-line measuring devices are installed, the pH values on-line measuring device is used to detect two reacted in the tank body in real time
The pH values of the reaction solution in secondary filtrate and magnesium source, the acid solution case, lye tank are detected according to the pH values on-line measuring device
The pH values of the reaction solution gone out acid solution or lye are launched into the tank body to adjust the pH values of reaction solution 7.5~
Between 8.5.
Further, the guanite retracting device is additionally provided with PLC control system, is respectively arranged at the magnesium source addition
Mouth, inlet, leakage fluid dram, acid solution case, the control valve of lye tank and discharge gate valve, circulation return pipe, pH value on-line checking
Device is respectively electricly connected with the PLC control system.
A kind of advantageous effect for the method and system recycling guanite from sludge of the present invention is:It is first to thickened sludge
Be ultrasonically treated so that thickened sludge is broken to lead to cell rupture, to promote intracellular water and PO4 3-It discharges to liquid phase
It is interior, then be separated by solid-liquid separation by diaphragm plate frame filter press, then into the secondary filtrate obtained after separation of solid and liquid addition magnesium source into
Row guanite reaction treatment is to obtain guanite particle, to effectively reduce the phosphorus concentration in sludge dewatering filtrate, reduces dirty
The sludge dewatering filtrate of water treatment plant returns to load;And by the supersound process to sludge, promote the big portions solid-state TP in sludge
Divide with PO4 3-Form is transferred in liquid phase, the phosphorus content in sludge dewatering filtrate after sludge is separated by solid-liquid separation is effectively increased, after being
The continuous guanite extraction recovery that improved out of sludge dewatering filtrate creates advantage;Also, carrying out diaphragm plate frame press filtration
Any chemical conditioning medicament need not be added in supersound process before processing, supersound process can be such that sludge inner cell moisture releases
It puts that sludge Free water ratio is made to increase, reduces dehydration difficulty of the subsequent diaphragm plate frame filter press to sludge, and advantageous
In the mud cake for obtaining more low-water-content, sludge reduction is fully realized.
In addition, the guanite reaction retracting device in the present invention in system uses external circulation return pipe to secondary mistake
Sludge dewatering filtrate after filter carries out closed loop forced circulation with magnesium source and reacts, thus it will not cause to analyse during reaction treatment
The guanite fine grained gone out is lost in water outlet, ensures the effluent quality and guanite recovering effect of filtrate;And as a result of
The mode of closed loop forced circulation reaction, it is thus possible to coordinate the work period in diaphragm plate frame press filtration face and realize guanite recycling
Batch-type operate, while inside it by liquid distribution trough and reactor come realize circular response solution flow stirring by no longer
It needs that blender is arranged, can also effectively reduce the volume of tank body and reduce floor space, save capital construction and equipment investment.
Description of the drawings
Fig. 1 is that a kind of system recycling guanite from sludge of the present invention constitutes schematic diagram;
Fig. 2 is the structural schematic diagram that guanite reacts retracting device in the present invention.
In attached drawing, 10 be sludge concentration tank, and 11 be discharge port, and 20 be Sludge by Ultrasonic retort, and 21 be feed inlet, and 22 be row
Material mouth, 23 be ultrasonic generator, and 24 be agitating device, and 30 be diaphragm plate frame filter press, and 31 be feed inlet, and 32 go out for filtrate
Mouthful, 33 be mud cake exhaust end, and 40 guanites react retracting device, and 41 be inlet, and 42 be magnesium source adding mouth, and 43 be leakage fluid dram,
44 be discharge gate valve, and 45 be tank body, and 451 be top reaction zone, and 4511 be top circulation fluid refluxing opening, and 4512 be bottom cycle liquid
Import, 452 be bottom decanting zone, and 453 be overflow port, and 46 be circulation return pipe, and 47 be liquid distribution trough, and 48 be reactor,
481 be stainless steel reaction lining, and 482 be stainless (steel) wire, and 483 be flow-stopping plate, and 484 be flow-stopping plate, and 49 fill for pH value on-line checkings
It sets, 50 be filter device, and 60 be acid solution case, and 70 be alkaline case.
Specific implementation mode
See Fig. 1, a kind of system recycling guanite from sludge of the invention comprising
Sludge concentration tank 10, the concentration for sludge are collected;
Sludge by Ultrasonic retort 20, for being ultrasonically treated to thickened sludge so that thickened sludge is broken to lead to cell
Rupture promotes intracellular water and PO4 3-Release, ultrasonic generator 23 and stirring are provided in Sludge by Ultrasonic retort 20
Device 24;
Diaphragm plate frame filter press 30 detaches to obtain solid phase for being separated by solid-liquid separation to the thickened sludge after sonicated
Mud cake and liquid phase filtrate;
Filter device 50 carries out secondary filter with to liquid phase filtrate, to obtain secondary filtrate;
Guanite reacts retracting device 40, is collected for carrying out guanite reaction to the liquid phase filtrate;
The wherein feed inlet 21 of 11 pipeline of the discharge port connection Sludge by Ultrasonic retort 20 of sludge concentration tank 10, Sludge by Ultrasonic
The feed inlet 31 of 22 pipeline of the discharge gate connection diaphragm plate frame filter press 30 of retort 20, the filtrate of diaphragm plate frame filter press 30 go out
The inlets 41 that mouth 32 reacts retracting device 40 by filter device 50 with guanite are connect, and guanite reacts retracting device 40
Equipped with magnesium source adding mouth 42, the bottom of guanite reaction retracting device 40 is provided with leakage fluid dram 43 and discharge gate valve 44.
See Fig. 2, it includes tank body 45 and external circulation return pipe 46 that guanite, which reacts retracting device 40, is arranged in tank body 45
It is in back taper to have top reaction zone 451 and bottom decanting zone 452, bottom decanting zone 452, and top reaction zone 451 is settled with bottom
It is provided with liquid distribution trough 47 between area 452, reactor 48, magnesium source adding mouth 42, inlet are installed in top reaction zone 451
41 are connected by pipeline into liquid distribution trough 47 respectively, and the top reaction zone 451 of tank body 45 is provided with top circulation fluid refluxing opening
4511 and bottom cycle liquid import 4512, circulation return pipe 46 and top circulation fluid refluxing opening 4511, bottom cycle liquid import
4512 difference piping connections, 4512 piping connection of bottom cycle liquid import enter liquid distribution trough 47;Reactor 48 includes hollow
Stainless steel reaction lining 481, stainless copper reaction lining 481 is interior to be filled with stainless (steel) wire 482;The top of stainless steel reaction lining 481
Portion, bottom are respectively arranged with flow-stopping plate 483,484.
The tank body 45 of guanite retracting device 40 is also respectively connected with acid solution case 60, lye tank 70, and is installed on tank body 45
Have a pH values on-line measuring device 49, pH values on-line measuring device 49 for detect in real time the secondary filtrate reacted in tank body 45 and
The pH values of the reaction solution in magnesium source, the reaction that acid solution case 60, lye tank 70 are detected according to pH values on-line measuring device 49 are molten
The pH values of liquid launch acid solution or lye into tank body 45 to adjust the pH values of reaction solution between 7.5~8.5.
Guanite retracting device 40 is additionally provided with PLC control system, for the automation to entire birds droppings retracting device 40
Operation is controlled, and the control of magnesium source adding mouth 42, inlet 41, leakage fluid dram 43, acid solution case 60, lye tank 70 is respectively arranged at
Valve and discharge gate valve 44, circulation return pipe 46, pH value on-line measuring device 49 respectively with the automatically controlled company of PLC control system
It connects.
Below in conjunction with the accompanying drawings, the method for using present system to recycle guanite from sludge is specifically described:
Embodiment one:
The thickened sludge that moisture content is 97% in sludge concentration tank 10 is pumped by discharge port 11 by feed inlet 21 ultrasonic anti-
It answers in tank 20, opens ultrasonic generator 23 and agitating device 24 and surpass to entering the thickened sludge in ultrasonic reaction pot 20
The ultrasonic power of sonication, ultrasonic generator 23 is set as 0.4W/mL, sonication treatment time 60 minutes;
By sonicated thickened sludge from discharge gate 22 be discharged ultrasonic reaction pot 20 and by feed inlet 31 be pumped into every
Diaphragm plate frame, which is taken by force, carries out solid-liquid separation treatment in filter press 30, control feed pressure is 1.0Mpa, feed time is 1.5 hours, pressure
Power control is squeezed in 1.6Mpa, 1.0 hours time of squeezing, the solid phase after filter-press dehydration is handled in sludge is mainly with moisture content
55% or so mud cake form, which is unloaded and transported outward from mud cake exhaust end 33, carries out following resource processing, containing from thickened sludge
The PO released4 3-Filtrate through filtrate (liquid 32 be discharged, wherein dehydrated sludge cake discharge time control at 0.5 hour.
The filtrate being discharged from filtrate (liquid 32 carries out secondary filter by secondary filter and obtains secondary filtrate, control two
The suspension content < 10mg/L of secondary filtrate;
Secondary filtrate is pumped into guanite by inlet 41 and reacts in the tank body 45 of retracting device 40 to PLC controls after setting liquid level
The valve of inlet 41 is closed in system control processed, stops feed liquor, and then PLC control system control loop reflux pump 46 is opened, and is followed
Ring reflux pump 46 sucks filtrate from top circulation fluid refluxing opening 4511, then enters liquid distribution trough by bottom cycle liquid import 5412
47, rise the stainless (steel) wire 482 flowed through in stainless steel reaction lining 481 through liquid distribution trough 47, by Mg:P molar ratios 1.4:1
Ratio adds magnesium source into tank body from magnesium source adding mouth 42 and is distributed into stainless steel reaction lining 481 by liquid distribution trough 47
In interior stainless (steel) wire 482, the magnesium source added in the present embodiment is MgCl2, reaction unit is connected with pH value on-line computing model, controls
PH ranges processed in 7.5-8.5, reflux filtrate, addition magnesium source formed under liquid distribution trough 47 and the effect of flow-stopping plate 483,484
The disturbance flow risen is recycled, disturbance flow flows through stainless (steel) wire 482, guanite crystallite under the action of turbulence prediction, collision
Start to generate, the crystallite being then refluxed in filtrate accelerates the increasing of struvite crystals particle but also as crystal seed, with reaction
It carries out, guanite bulky grain is settled down to bottom decanting zone 452, and whole guanite reaction time control was entirely being reacted at 2 hours
PH value on-line measuring device 49 carries out real-time pH values detection, PLC control system root to the reaction solution in tank body 45 in the process
Acid solution or lye are launched into tank body 45 to realize according to the pH value testing results control acid solution case 60, the lye tank 70 that receive
PH values are adjusted such that in 7.5~8.5 control range to the pH values of the reaction solution in tank body 45, reaction terminates
The valve of PLC control system control leakage fluid dram 43 opens emptying filtrate afterwards, and filtrate is back to sewage plant and is further processed, and controls
The discharge gate valve 44 of bottom is opened, guanite product is obtained.
The guanite reaction retracting device of present system also there is cleaning function to empty entire bird usually every 30 days
Coprolite reaction unit, by inlet 41 from liquid distribution trough 47 the injected clear water washing lotion into tank body, start circulation return pipe 46,
Acid solution is pumped by acid solution case 60 according to pH testing results, is recycled 30~60 minutes, excludes to use by 45 bottom discharging gate valve 44 of tank body
It is stopped operation when without apparent fouling product in the pickle of cleaning;Acid solution ratio and concentration can be according to the fouling thickness on tube wall
Targetedly adjusted.Cleaning set time 1h or pH value tend in a certain range, it is believed that cleaning terminates, circulation cleaning device
It is stopped, diluted acid is evacuated by return-flow system, carries out clear water cleaning again, completes cleaning process.
The difference of embodiment two and embodiment one is that the ultrasonic power of ultrasonic generator 23 is set as 0.2W/mL, surpasses
75 minutes sonication time, guanite, which reacts, presses Mg in removal process:P molar ratios 1.5:1 ratio adds MgCl2And pass through
Liquid distribution trough 47 is distributed into the stainless (steel) wire 482 in stainless steel reaction lining 481.
Implementation three and the difference of embodiment one, two are that the ultrasonic power of ultrasonic generator 23 is set as 0.5W/mL,
Sonication treatment time 90 minutes, guanite, which reacts, presses Mg in removal process:P molar ratios 1.3:1 ratio adds MgCl2And lead to
It crosses in the stainless (steel) wire 482 that liquid distribution trough 47 is distributed into stainless steel reaction lining 481.