CN207958003U - A kind of landfill leachate nanofiltration concentrate treatment combined device - Google Patents

Abstract

The utility model provides a kind of landfill leachate nanofiltration concentrate treatment combined device, and the combination unit is made of iron-based flocculation deposition apparatus, class Fenton advanced oxidation device and activated carbon adsorption device three parts.Iron-based flocculation deposition apparatus includes flocculation stirring slot, pH automatic control systems and sedimentation basin；Class Fenton advanced oxidation device includes middle tank, class Fenton reactive tank and oxidation-reduction potential automatic control system；Activated carbon adsorption device includes middle tank and activated carbon adsorption bed.Landfill leachate nanofiltration concentrate initially enters iron-based flocculation deposition apparatus and carries out flocculation sediment, flocculation reaction supernatant enters class Fenton advanced oxidation device and carries out class Fenton reaction, and the reaction water outlet of class Fenton enters activated carbon adsorption device and carries out adsorption reaction.This combination unit can efficiently realize the removal of hardly degraded organic substance, heavy metal in landfill leachate nanofiltration concentrate, to provide effective way for the processing of landfill leachate nanofiltration concentrate is difficult in field of water pollution control, is discharged the solution of the big problem of toxicity.

Description

A kind of landfill leachate nanofiltration concentrate treatment combined device

Technical field

The utility model is related to field of water pollution control, particularly relate to a kind of landfill leachate nanofiltration concentrate processing combination Device.

Background technology

To make landfill yard water outlet meet《Household refuse landfill sites contamination control standard》(GB16889-2008) stringent rule It is fixed, national Large-scale Landfill Leachate processing generally use full membrane process (bioreactor-nano filtering membrane-reverse osmosis process, That is MBR-NF-RO techniques), although the technique can make tail water qualified discharge, after completing physical filtering, nanofiltration (NF) and anti- Infiltration (RO) process will produce 20~30% into the film filtration concentrated of water volume simultaneously.As preamble filter progress, nanofiltration meeting Effectively catching bigger molecule organic matter, divalent and polyvalent metal ion etc., make in nanofiltration concentrate containing the difficult to degrade of high concentration Organic matter and heavy metal ion, while its salinity is high, intractability up to standard is big, becomes the bottleneck encountered in full membrane process application Problem.

So far, has the methods of film concentration, recharge landfill yard, evaporate-crystallization and flocculation sediment-advanced oxidation quilt For nanofiltration concentrate processing, though they can obtain certain treatment effect, there is also some problems simultaneously.Patent of invention CN1923875 and CN103964609 individually disclose it is a kind of by film method for concentration for rubbish percolation liquid membrane concentrate processing Method, although this method can further cut down the film volume of the concentrated liquid, operating pressure needed for technique and of high cost, while face Face the problem of producing water ratio is low, newly generated film concentrate still needs to processing.As a kind of traditional processing method, recharge landfill yard is easy Secondary pollution is generated, cannot be tackled the problem at its root.Patent CN103570157 and CN104211245 are using at evaporation technology Manage rubbish percolation liquid membrane concentrate, this technique have the advantages that processing it is thorough, easy to operate, but exist simultaneously operating cost height, The serious problem of corrosion and scaling.By means of the strong oxidizing property of produced free radical, advanced oxidization method can be realized difficult to degrade organic The efficient removal of object, and operation is easy to operate, is increasingly becoming the hot spot of research and Patent exploitation.Patent CN104478157 and CN105130088 discloses two kinds of landfill leachate nanofiltration concentrate processing combination works comprising flocculation sediment-advanced oxidation Skill, but above-mentioned two-step pretreatment process cannot still be such that water outlet reaches《Household refuse landfill sites contamination control standard》(GB16889- 2008) requirement.For this purpose, patent CN104478157 connects again after electrolysis processing, ozone Oxidation Treatment process carrys out intensive treatment Effect.But the Active Chlorine that is generated in advanced oxidation processes while it can be reacted with humic acid in concentrate and generate harmful by-products, had It may lead to stronger toxicity.Therefore, it is necessary to develop a kind of landfill leachate nanofiltration concentrate processing group regarding to the issue above It attaches together and sets.

Patent of invention content

In view of this, being attached together the purpose of this utility model is that developing a kind of landfill leachate nanofiltration concentrate processing group It sets, which can efficiently remove organic matter and heavy metal pollution in landfill leachate nanofiltration concentrate simultaneously, and by reducing out Harmful by-products concentration improves water outlet safety in water.

Based on above-mentioned purpose, a kind of landfill leachate nanofiltration concentrate treatment combined device provided by the utility model, this Combination unit includes iron-based flocculation deposition apparatus, class Fenton advanced oxidation device and activated carbon adsorption device three parts, tool Body includes：

(1) iron-based flocculation deposition apparatus：A kind of landfill leachate nanofiltration concentrate processing combination according to the present utility model Device, which is characterized in that iron-based flocculation deposition apparatus includes flocculation stirring slot, pH automatic control systems and sedimentation basin three parts. Wherein, flocculation stirring slot mainly completes the water inlet of landfill leachate nanofiltration concentrate, and iron-based flocculant and flocculation aid add, and pass through Different mixing speeds, which is arranged, in frequency modulator completes flocculation and helps solidifying process.In flocculation process, pass through pH automatic control system controls System reaction is under the conditions of optimum pH.PH automatic control systems are mainly by pH probes, pH auto-controllers, sour bucket, alkali bucket, acid The compositions such as pump, alkali pump.The water outlet for completing flocculation reaction enters sedimentation basin, is discharged into after sufficient standing and reacts in next step.

(2) class Fenton advanced oxidation device：At a kind of landfill leachate nanofiltration concentrate according to the present utility model Reason combination unit, which is characterized in that class Fenton advanced oxidation device includes middle tank, class Fenton advanced oxidation slot With oxidation-reduction potential (oxidation-reduction potential, ORP) automatic control system.Middle tank passes through storage Deposit the continuum micromeehanics that flocculation water outlet ensures class Fenton advanced oxidation slot.Class Fenton advanced oxidation slot is mainly continuous Under stirring condition, the degradation of organic matter is carried out by means of class Fenton advanced oxidation processes.It is advanced in the class Fenton Chemical reaction shown in main generating polynomial (1)-(4) in oxidation process, and required catalyst precursors are reacted by iron-based flocculation sediment Residual F e in water outlet³⁺It provides, this so that device is successive good, avoids the secondary of required catalyst precursors and adds, has Help improve efficiency and reduces cost.ORP automatic control systems include：ORP probes, ORP auto-controllers, regulated power supply and Power switch etc..When ORP value is less than class Fenton process appropriate redox potential region, regulated power supply switch keeps closing Conjunction state is constantly aoxidized chlorion by anode and generates Active Chlorine promotion system oxidation-reduction potential, when ORP value is more than suitable for oxygen When changing reduction potential section high level, regulated power supply switch is opened, and system current potential declines, until being less than appropriate redox voltage belt Between low value when, regulated power supply switch be closed again.By being recycled above so that system ORP is maintained at most suitable section.By means of Fe²⁺ Catalysis and control of the ORP automatic control systems to system current potential can reduce the harmful by-products caused by excessive Active Chlorine generates Yield.

Cathode：Fe³⁺+e^-→Fe²⁺ (1)

Anode：2Cl^--2e^-→Cl₂(aq) (2)

Solution：Cl₂(aq)+H₂O→HClO+Cl^-+H⁺ (3)

HClO+Fe²⁺→Fe³⁺+·OH+Cl^- (4)

(3) activated carbon adsorption device：A kind of landfill leachate nanofiltration concentrate processing group according to the present utility model attaches together It sets, which is characterized in that activated carbon adsorption device includes middle tank and activated carbon adsorption bed.The effect of middle tank is mainly logical It crosses and stores the water outlet of class Fenton advanced oxidation device to ensure the continuum micromeehanics of activated carbon adsorption bed.Activated carbon adsorption bed is simultaneously The harmful by-products generated in remaining small organic molecule and advanced oxidation processes are adsorbed, realize landfill leachate nanofiltration concentration The highly effective and safe of liquid is handled.In the process of running, landfill leachate nanofiltration concentrate enters iron from flocculation stirring trench bottom first In the case where pH is automatically controlled and stirred with blender flocculation reaction occurs for base flocculation deposition apparatus, and later, flco is stirred with waste water by flocculating Trench bottom gravity flow is mixed into the top of sedimentation basin, and realizes flco and clear liquid separation in sedimentation basin.Then, class electricity is utilized Fenton advanced oxidation devices handle the water outlet of iron-based flocculation deposition apparatus：Supernatant is pumped by sedimentation basin bottom after flocculation reaction At the top of middle tank, water sample is pumped by its bottom at the top of class Fenton reactive tank in middle tank, and is automatically controlled in ORP Lower progress class Fenton reaction is stirred with blender.Then, the advanced oxygen of class Fenton is handled using activated carbon adsorption device Disguise the water outlet set：Class Fenton reaction water outlet is pumped into activated carbon adsorption device by pump, and activated carbon adsorption device is intake the bottom of by Portion enters, and top is overflowed.

From the above it can be seen that a kind of landfill leachate nanofiltration concentrate processing group provided by the utility model attaches together It sets and has the advantages that：

1. it is good to combine the unit each section linking.Iron-based flocculation deposition apparatus mainly removes humic acid etc. in nanofiltration concentrate Larger molecular organics, class Fenton advanced oxidation device can be such that organic matter molecular mass further decreases, to improve activated carbon The adsorption efficiency of adsorbent equipment.Remaining Fe in the water outlet of iron-based flocculation deposition apparatus³⁺Can be class Fenton advanced oxidation processes Catalyst precursors are provided, to avoid the secondary of molysite from adding.It is high that activated carbon adsorption device can adsorb class Fenton simultaneously The harmful by-products contained in grade oxidation unit water outlet, improve the safety of final outflow water.

2. combination unit is with strong points to the processing of landfill leachate nanofiltration concentrate, effect is good.Iron-based flocculation deposition apparatus The humic acid material that degradation is most difficult in nanofiltration concentrate can be efficiently removed, to mitigate the pressure of aftertreatment device.For Nanofiltration concentrate middle and high concentration heavy metal and its characteristic that can be combined with organic matter, iron-based flocculation deposition apparatus are realizing organic matter Heavy metal in water can be largely removed while removal.As a kind of high salinity waste water, in nanofiltration concentrate a large amount of existing chlorine from Son provides sufficient substrate for class Fenton advanced oxidation processes, to be conducive to the efficient degradation of organic matter.

3. class Fenton advanced oxidation device is efficient to organic matter removal, harmful by-products content is low.Different from general Energization solution preocess, in class Fenton reaction process, the Fe of cathodic reduction generation²⁺The Active Chlorine that catalyticing anode generates generates oxygen The extremely strong OH of the property changed, to realize the efficient removal of hardly degraded organic substance.Meanwhile the setting of ORP automatic control systems avoids The generation of excessive Active Chlorine, this helps to reduce the amount that Active Chlorine and humic acid etc. react generation harmful by-products.

Description of the drawings

The utility model is described further with reference to the accompanying drawings and detailed description.

Attached drawing 1 is the connection diagram of the utility model embodiment.

Wherein：1：PH automatic control systems, including 1-1：Sour bucket, 1-2：Acid pump, 1-3：PH auto-controllers, 1-4：1# is opened It closes, 1-5：Alkali bucket, 1-6：Alkali pump, 1-7：PH pops one's head in；2：Flocculation stirring slot；3：1# frequency modulators；4：Sedimentation basin；5：1# water pumps；6： 1# middle tanks；7：2# water pumps；8：ORP automatic control systems, including 8-1：Regulated power supply, 8-2：ORP auto-controllers, 8- 3：2# switches, 8-4：ORP pops one's head in；9：Class Fenton reactive tank；10：2# frequency modulators；11：3# water pumps； 12：2# middle tanks； 13：3# water pumps；14：Activated carbon adsorption bed.

Specific implementation mode

To make the purpose of this utility model, technical solution and advantage be more clearly understood, below in conjunction with specific embodiment, and With reference to attached drawing, the utility model is further described.

A kind of landfill leachate nanofiltration concentrate treatment combined device of the utility model, including iron-based flocculation sediment dress It sets, class Fenton advanced oxidation device and activated carbon adsorption device three parts.As shown in Figure 1, rubbish oozes in the utility model Filtrate nanofiltration concentrate initially enters iron-based flocculation deposition apparatus, specifically：Suitable iron-based wadding is added into flocculation stirring slot 2 Solidifying agent, being utilized respectively 1# frequency modulators 3 and pH automatic control systems 1 makes reaction obtain suitable mixing speed and pH value, to reach Good flocculating effect is then added suitable flocculation aid and is slowly stirred by adjusting 1# frequency modulators 3, imitated with intensified coagulation Fruit.Flocculation water outlet gravity flow enters sedimentation basin 4, the destruction to avoid pump to flco.Sedimentation basin water outlet is pumped into 1# by 5 batch of 1# water pumps In middle tank 6,2# water pumps 7 are sent into from 6 continuous pumpage of 1# middle tanks in class Fenton reactive tank 9, while opening voltage stabilizing Power supply 8-1 and blender adjust 2# frequency modulators 10 and obtain suitable for mixing speed, realize mass transfer enhancement first.In order to provide class electricity Optimum ORP current potentials needed for Fenton reactions, while avoiding causing the generations of excessive harmful by-products because ORP is excessively high, this Combination unit controls ORP current potentials in class Fenton reactive tank 9 using ORP automatic control systems 8, specifically, in electrolytic process In, because of the continuous generation of Active Chlorine, ORP current potentials can be increased constantly in class Fenton reactive tank 9, when ORP probes 8-4 is measured When ORP value is higher than the ORP upper limits set, ORP auto-controllers 8-2 control 2# switches 8-3 is disconnected, ORP after electrolytic process stops Current potential is begun to decline, and when value is less than the ORP lower limits set, ORP auto-controllers 8-2 control 2# switches 8-3 is closed, and ORP is again Secondary raising, higher than being again off after the upper limit, cycle makes ORP current potentials in class Fenton reactive tank 9 be in setting model always successively In enclosing.The water outlet of class Fenton reactive tank 9 is first pumped into 2# middle tanks 12 through 3# water pumps 11, with regulating pondage, ensures activated carbon The continuum micromeehanics of adsorbent bed 14.The water inlet of activated carbon adsorption bed 14 is pumped by 4# water pumps 13, and flow is entered by bottom, top It overflows.

Embodiment 1

Percolate nanofiltration concentrate is derived from certain aged city life garbage landfill, percolate processing using biofilm+ External ultrafiltration (UF)+nanofiltration (NF) treatment process, produced nanofiltration concentrate coloration are 4000 times, COD 3500mg/ L, BOD₅For 100mg/L, salinity 14800mg/L, conductivity is 18200 μ S/cm, and heavy metal concentration is as shown in table 1, wherein Cr, As and Hg concentration is more than《Household refuse landfill sites contamination control standard》(GB16889-2008) limit value.Above-mentioned nanofiltration Concentrate is pumped to first in flocculation stirring slot, and flocculant FeCl is then added₃.6H₂O, and make Fe in flocculation stirring slot³⁺Concentration For 5.0mmol/L.During flocculation reaction, reaction pH is controlled between 2.95-3.05 using pH automatic control systems, then Flocculation aid polyacrylamide is added and makes its a concentration of 5mmol/L, flowing automatically after mixing slowly enters sedimentation basin.Sedimentation basin be discharged with Raw water is compared：COD removals 63%, color removal 65%, and residual F e³⁺About 1.4mmol/L.Sedimentation basin is discharged through middle tank tune Class Fenton reactive tank is continuously pumped into after water-saving amount.Electrode slice arrangement mode is in class Fenton reactive tank：Monopole electricity Pole piece 4, two-by-two spacing 3cm.Current density used is 12mA/cm², mixing speed 350r/min, hydraulic detention time 200min, while being between 895-905mV by ORP in ORP automatic control system control systems.It is reacted through class Fenton Afterwards, it is discharged COD and coloration is further removed, the COD removal rates that two parts reach before combining the unit are 75%, and coloration is 81%, but simultaneously because generate reacting for Active Chlorine and humic acid etc., in water outlet while producing the haloform of 36 μm of ol/L THMs.Rest COD, coloration and newly generated harmful by-products etc. continue to be removed by the activated carbon adsorption bed in combining the unit.Institute It is 80cm, hydraulic detention time 40min with activated carbon adsorption bed height.By the processing of full set combination unit, effluent color dilution It is completely removed, COD residues 50mg/L is hereinafter, heavy metal realizes preferable removal, and As and Hg realize qualified discharge, and Cr is super Mark ratio declines to a great extent.In addition, newly generated THMs is also removed 62% after activated carbon adsorption bed adsorbs.

Device heavy metal concentration variation (μ g/L) before and after the processing in 1 the utility model embodiment 1 of table

Element	Cr	Ni	As	Cu	Zn	Se	Sb	Hg
									Before processing	756.3	952.4	289.2	100.6	722.3	20.3	49.5	3.2
After processing	111.6	168.2	30.2	31.3	385.3	10.5	20.6	0.44

Embodiment 2

Percolate nanofiltration concentrate is derived from certain city life garbage landfill, and percolate processing is using biofilm+external Formula ultrafiltration (UF)+nanofiltration (NF) treatment process, produced nanofiltration concentrate coloration are 3800 times, COD 3000mg/L, BOD₅For 200mg/L, salinity 13300mg/L, conductivity is 14500 μ S/cm, and heavy metal concentration is as shown in table 2, similarly, Wherein Cr, As and Hg concentration is more than《Household refuse landfill sites contamination control standard》(GB16889-2008) limit value.It is above-mentioned Nanofiltration concentrate is pumped to first in flocculation stirring slot, and flocculant Fe (NO are then added₃)3.6H₂O, and make in flocculation stirring slot Fe³⁺A concentration of 10.0mmol/L.During flocculation reaction, using pH automatic control systems control reaction pH 4.95-5.05 it Between, it is subsequently added into flocculation aid polyacrylamide and makes its a concentration of 8mmol/L, flowing automatically after mixing slowly enters sedimentation basin.Precipitation Pond is discharged compared with raw water：COD removals 60%, color removal 61%, and residual F e³⁺About 5.6mmol/L.In sedimentation basin water outlet warp Between be continuously pumped into class Fenton reactive tank after sink regulating pondage.Electrode slice arrangement mode in class Fenton reactive tank For：Monopolar electrode piece 2, two-by-two spacing 2cm.Current density used is 20mA/cm², mixing speed 400r/min, hydraulic retention Time 180min, while being between 1095-1105mV by ORP in ORP automatic control system control systems.Through class electricity After Fenton reactions, it is discharged COD and coloration is further removed, the COD removal rates that two parts reach before combining the unit are 76%, Coloration is 79%, but simultaneously because generate reacting for Active Chlorine and humic acid etc., in water outlet while producing the three of 42 μm of ol/L Halomethane THMs.The continuation such as rest COD, coloration and newly generated harmful by-products is gone by the activated carbon adsorption bed in combining the unit It removes.Activated carbon adsorption bed height used is 70cm, hydraulic detention time 35min.By the processing of full set combination unit, water outlet Coloration is completely removed, and for COD residues 60mg/L hereinafter, heavy metal realizes preferable removal, Cr, As and Hg realize row up to standard It puts.In addition, newly generated THMs is also removed 70% after activated carbon adsorption bed adsorbs.

Heavy metal concentration variation (μ g/L) before and after process in 2 embodiment of the present invention 2 of table

Element	Cr	Ni	As	Cu	Zn	Se	Sb	Hg
									Before processing	659.6	775.2	254.9	85.6	485.6	16.2	52.3	4.52
After processing	98.6	125.6	32.3	25.3	258.9	15.6	20.6	0.3

Those of ordinary skills in the art should understand that：The discussion of any of the above embodiment is exemplary only, not It is intended to imply that the scope of the present disclosure (including claim) is limited to these examples；Under the thinking of the utility model, the above reality Applying can also be combined between the technical characteristic in example or different embodiment, and there are the utility model as described above Many other variations of different aspect, for simplicity, they are not provided in details.Therefore, all spirit in the utility model Within principle, any omission, modification, equivalent replacement, improvement for being made etc. should be included in the scope of protection of the utility model Within.

Claims (3)

1. a kind of landfill leachate nanofiltration concentrate treatment combined device, which is characterized in that including iron-based flocculation deposition apparatus, class Fenton advanced oxidation device and activated carbon adsorption device three parts；

The iron-based flocculation deposition apparatus is made of flocculation stirring slot, pH automatic control systems and sedimentation basin, the flocculation stirring Slot configures blender at top, and the blender connection frequency modulator adjusts mixing speed.Landfill leachate nanofiltration concentrate is the bottom of by Portion enters flocculation stirring slot, and carries out flocculation precipitation reaction；Later, flco is entered with waste water by the gravity flow of flocculation stirring trench bottom heavy The top in shallow lake pond.The class Fenton advanced oxidation device includes middle tank, class Fenton reactive tank and redox Current potential automatic control system；The class Fenton reactive tank configures blender, and the blender connection frequency modulator adjusts stirring Speed；Supernatant is pumped by sedimentation basin bottom at the top of middle tank after flocculation reaction, and water sample is pumped by its bottom in middle tank Class Fenton reaction is carried out at the top of class Fenton reactive tank；Class Fenton reaction water outlet is pumped into activated carbon adsorption dress by pump It sets, activated carbon adsorption device water inlet is entered by bottom, and top is overflowed.

2. combination unit according to claim 1, which is characterized in that the class Fenton advanced oxidation device is used for Handle the water outlet of iron-based flocculation deposition apparatus.

3. combination unit according to claim 1, which is characterized in that the activated carbon adsorption device is for handling class electricity The water outlet of Fenton advanced oxidation devices.