CN102583764B - Combined packing multistage terrace type vertical flow constructed wetland sewage treatment method - Google Patents
Combined packing multistage terrace type vertical flow constructed wetland sewage treatment method Download PDFInfo
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- CN102583764B CN102583764B CN201210068327.3A CN201210068327A CN102583764B CN 102583764 B CN102583764 B CN 102583764B CN 201210068327 A CN201210068327 A CN 201210068327A CN 102583764 B CN102583764 B CN 102583764B
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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
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
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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
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
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Abstract
The invention belongs to the technical field of environmental protection and discloses a combined packing multistage terrace type vertical flow constructed wetland sewage treatment method, which comprises the following steps of: precipitating domestic sewage subjected to secondary biochemical treatment, and allowing the domestic sewage to enter a multistage terrace type vertical flow constructed wetland consisting of combined packing, so that water is purified. The method has the advantages of good treatment effect, high efficiency, high impact load resistance, stable operation, low investment cost and the like. Limits of pollutant discharge in the treated effluent reach the grade-A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002), wherein the chemical oxygen demand (COD) is less than 50mg/L, the ammonia nitrogen is less than 5mg/L, the total phosphorus is less than 0.5mg/L, and the total nitrogen is less than 15mg/L, so that the effluent can be directly discharged.
Description
Technical field
The invention belongs to environmental protection technical field, relate to the multistage terrace-type vertical flow constructed wetland sewage treatment method of a kind of combined stuffing.
Background technology
China agricultural samll cities and towns focus mostly in middle part and western mountainous areas and knob, belong to economically less developed region, are subject to the restriction of the level of economic development, and they are often difficult to bear the great number Construction and operation of large-scale wastewater treatment plant and the expense of maintenance.Because agriculture population in small towns scale is less, live and comparatively disperse, so sanitary sewage has the features such as discharge disperses, and water quality and water yield fluctuation are large.After existing agriculture Small Town Wastewater processing mode mostly still is one-level septic tank dispersion treatment, directly enter river course nearby, and along with cities and towns expanding economy, quantity of wastewater effluent continues to increase, and will cause severe contamination to receiving water body.China is the country on mountain more than, and due to topographical condition and the local level of economic development, traditional large-scale centralized formula sewage treatmentmethod can run into larger difficulty.Therefore, anxious exploitation to be studied is according to the waste water treatment technology of low energy consumption of suiting measures to local conditions and the practical sewage treatment process of locality nature, economy and society condition.
Artificial swamp is as a kind of emerging ecological sewage treatment technique, more and more be subject to people's attention, this process operation is safeguarded simple, and can tackle preferably load impact, also can effectively remove organism, nitrogen, the phosphorus in sewage, be a kind of sewage water treatment method having wide application prospects.Compare with conventional processes, fabrication cost and the working cost of artificial swamp are lower, operational administrative is simple, treatment effect good.By the apolegamy of wetland structure design, filler, plant, the adjusting of operation condition etc., can make water outlet reach < < water environment quality standard > > (GB3838-2002) I class to IV class standard, after processing, water can be used as landscape water and farmland irrigation water.The current patent of invention around artificial swamp application approximately has kind more than 300, its type of skill can roughly be divided into following a few class: the artificial wetland process designing around specific influent quality, the advanced treatment of this type of technique spininess to trade effluent, as CN101254974 method of processing arsenic-containing waste water with Herba pteridis vittatae artificial swamp; The optimization of the technique of artificial swamp, generally comprise the optimization of artificial swamp element, use new filler, study the use of combining of novel wetland plant or artificial swamp and other techniques, as mono-kind of CN101514053 is usingd steel-making waste residue as the eutrophication water body artificial wetland processing system of matrix, CN101445300 eutrophic water low-energy consumption mobility bed-constructed wetland combination treatment method.But these inventions are many from processing object or processing means, local ecological resources and terrain feature do not taken in.In addition,, because the power of Wastewater Treatment by Constructed Wetlands mainly comes from sun power, therefore numerous investigators often ignore energy consumption problem in further reduction wetland technology.There is the feature that topographical elevation difference is large in China agricultural samll cities and towns their location, sometimes the topographical elevation difference of same samll cities and towns can reach tens meters of rice even up to a hundred, if make full use of this part potential energy, develop novel artificial wetland device, not only can significantly reduce the energy consumption cost of sewage disposal, and can provide sufficient oxygen for artificial swamp, be conducive to improve artificial wet land water quality purification efficiency.
Summary of the invention
For defect of the prior art, the object of this invention is to provide the multistage terrace-type vertical flow constructed wetland sewage treatment method of a kind of combined stuffing, after processing, in water outlet, the limit value of pollutant emission reaches the one-level A standard in < < urban wastewater treatment firm pollutant emission standard > > (GB18918-2002).
Technical scheme of the present invention is as follows:
The invention provides the multistage terrace-type vertical flow constructed wetland sewage treatment method of a kind of combined stuffing, the method comprises the following steps: after the sanitary sewage precipitation after secondary biochemical treatment, enter in the multistage terrace-type vertical current constructed wetland of combined stuffing formation, stop 2～5 days, water quality is purified.
Described multistage terrace-type vertical current constructed wetland long-width ratio is 1: 1.5-1: 3, have 4 grades of wetland device series operations, and between every grade, drop height is 400-800mm.
The combinations of plant that described multistage terrace-type vertical current constructed wetland is used is first step wetland: reed; Second stage wetland: Canna generalis Bailey; Third stage wetland: Herba Bidentis Bipinnatae; Fourth stage wetland: calamus.
Described combined stuffing is first step wetland: the large gravel that particle diameter is 15-18mm; Second stage wetland: the little gravel that particle diameter is 8-10mm; Third stage wetland: the little gravel that the large gravel that particle diameter is 15-18mm is 8-10mm with particle diameter mix gravel, large gravel and pebble stone volume ratio are 1: 1; Fourth stage wetland: the bamboo charcoal that the little gravel that particle diameter is 8-10mm and particle diameter are 3mm, both proportional ranges are 1: 1～1: 3.
Described combined stuffing layer thickness is 50～80cm.
Described first step wetland, second stage wetland, third stage wetland and fourth stage wetland are divided into inhalant region, wetland is processed main unit district, exhalant region; Current enter inhalant region by water inlet pipe, then by water distributor, vertically enter into wetland and process main unit district, then flow into exhalant region by perforation rising pipe.
Described sanitary sewage residence time in multistage terrace-type vertical current constructed wetland is 2～5 days.
The present invention compared with the existing technology, has the following advantages and beneficial effect:
1, construction cost of the present invention is low, can significantly reduce investment outlay, and operational management is convenient, and processing cost is low;
2, the present invention is according to the large feature of agriculture samll cities and towns' area topographical elevation difference, develop multistage terrace-type vertical current constructed wetland, this kind of practical waste disposal plant has the feature of low power energy-saving type, the series operation of 4 grades of constructed wetland devices simultaneously can increase substantially the purification efficiency of sanitary sewage, can extensively promote the use of at Mountainous town.
3, the present invention develops the artificial swamp that novel cheap filler bamboo charcoal and different-grain diameter gravel based on native country ecological resources are combined stuffing agriculture small town sewage is carried out to advanced treatment, both consider wetland construction cost, given full play to again the performance of each filler; Bamboo charcoal has comparatively special pore texture, can strengthen organic Adsorption in sewage, can provide good carrier for adhering to of microorganism again; Gravel has also guaranteed the removal effect to pollutents such as nitrogen, phosphorus as conventional filler.
4, the present invention, in foliage filter screening combined aspects, optimizes the native country wetland plant Herba Bidentis Bipinnatae pollutents such as nitrogen, phosphorus to good removal effect, and the sewage purification ability of simultaneously arranging in pairs or groups is strong and have wetland plant reed, Canna generalis Bailey and the calamus of landscape effect concurrently; The combination of above four kinds of wetland plants can bring to dewing graceful landscape effect when increasing wet land system processing power.
5, method of the present invention has the advantages such as treatment effect is good, efficiency is high, capacity of resisting impact load is strong, stable, investment cost is low.After processing, in water outlet, the limit value of pollutant emission reaches the one-level A standard in < < urban wastewater treatment firm pollutant emission standard > > (GB18918-2002), wherein COD is below 50mg/L, ammonia nitrogen is below 5mg/L, total phosphorus is below 0.5mg/L, total nitrogen, below 15mg/L, can directly discharge.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of the multistage terrace-type vertical flow constructed wetland sewage treatment method of the combined stuffing of the embodiment of the present invention 1.
Fig. 2 is single-stage constructed wetland device schematic side view.
Fig. 3 is single-stage constructed wetland device schematic top plan view.
Fig. 4 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of combined stuffing of the present invention to COD.
Fig. 5 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of combined stuffing of the present invention to ammonia nitrogen.
Fig. 6 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of combined stuffing of the present invention to total phosphorus.
Fig. 7 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of combined stuffing of the present invention to total nitrogen.
Embodiment
Below in conjunction with accompanying drawing illustrated embodiment, the present invention is further illustrated.
Fig. 1 is the schematic diagram of the multistage terrace-type vertical flow constructed wetland sewage treatment method of the combined stuffing of the embodiment of the present invention 1.After sanitary sewage precipitation after secondary biochemical treatment, enter in the multistage terrace-type vertical current constructed wetland of combined stuffing formation, multistage terrace-type vertical current constructed wetland long-width ratio is all can for 1: 1.5,1: 2 and 1: 3, have 4 grades of wetland device series operations, between every grade, drop height is that 400mm, 600mm or 800mm all can.Fig. 2 is single-stage constructed wetland device side-view; Fig. 3 is single-stage constructed wetland device vertical view.First step wetland, second stage wetland, third stage wetland and fourth stage wetland are of a size of 1m * 0.6m, height 0.8m, and first step wetland, second stage wetland, third stage wetland and fourth stage wetland are divided into inhalant region, wetland is processed main unit district, exhalant region; Current enter inhalant region by water inlet pipe 1, then by water distributor 2, vertically enter into wetland and process main unit district, then flow into exhalant region by perforation rising pipe 3.
The series connection of level Four vertical-flow wetland is used.The combinations of plant that multistage terrace-type vertical current constructed wetland is used is reed, Canna generalis Bailey, Herba Bidentis Bipinnatae, four kinds of emergents of calamus, is planted in respectively in multistage terrace-type vertical current constructed wetland the 1st, 2,3,4 stage arrangements.Combined stuffing layer thickness is that 50cm, 60cm or 80cm all can.Aspect filler layout, first step wetland is arranged the large gravel that particle diameter is 15-18mm, and second stage wetland is arranged the little gravel that particle diameter is 8-10mm, and third stage wetland is arranged the gravel that mixes of little gravel that large gravel that particle diameter is 15-18mm is 8-10mm with particle diameter; Large gravel and pebble stone volume ratio are 1: 1; Fourth stage wetland is that particle diameter is the mixing of little gravel and the bamboo charcoal that particle diameter is 3mm of 8-10mm, and both proportional ranges are 1: 1,1: 2 or 1: 3.This kind of array mode can either prevent dirty stifled, reduces head loss, can also utilize this part potential energy that has larger drop between wetland devices at different levels simultaneously, increases filler space oxygenation, for root system of plant and microorganism provide better growing environment.
The purification process of Wetlands on Wastewater is as follows: first by submersible pump, agriculture small town sewage is evacuated to elevated tank, sewage is natural subsidence in water head tank, and excessive sewage returns to hold well via overflow.Sewage residence time in tank be 1-3 days after simple precipitation, by water distribution system, make sanitary sewage vertical subsurface flow enter multistage terraced fields artificial swamp, its flooding velocity regulates flow rate control by pump.Effluent stream is through artificial swamps at different levels, and at the front end of combination type wetland, artificial swamp, by effects such as filtration absorb, is removed the pollutents such as organism, SS; In stage casing, by aerobic-anaerobic, react pollutents such as removing nitrogen phosphorus; At tail end, by the material of plant root exudation, suppress in addition the effect of pathogenic bacterium.
Wetland operation adopts the continuous water intake mode of 24h, intakes as agriculture small town sewage.Starting the operating period, get hydraulic detention time 5d, hydraulic load is 0.96m
3/ (m
2d).In operational process, according to effluent quality situation, progressively increase hydraulic load, finally can make the hydraulic detention time of this artificial swamp reach 2d, hydraulic load is 2.4m
3/ (m
2d).Through the operation result of continuous 6 wheat harvesting periods, show, thisly take the multistage terrace-type vertical current constructed wetland that bamboo charcoal and gravel be combined stuffing sanitary sewage is had to good adaptability, to COD, NH
4 +-N, TP, TN etc. have stable and removal effect preferably, and concrete treatment effect is shown in Fig. 4, Fig. 5, Fig. 6, Fig. 7.Fig. 4 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of the present invention to COD.Fig. 5 is that the multistage terrace-type vertical current constructed wetland of the present invention is to NH
4 +the treatment effect figure of-N.Fig. 6 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of the present invention to total phosphorus.Fig. 7 is the treatment effect figure of the multistage terrace-type vertical current constructed wetland of the present invention to total nitrogen.During the steady running of more than four months, in water inlet, COD mean concns is that 93.58mg/L, TN mean concns are that 19.64mg/L, TP mean concns are 1.55mg/L, NH
4 +-N concentration is 12.67mg/L, in water outlet, the limit value of pollutant emission reaches the one-level A standard in < < urban wastewater treatment firm pollutant emission standard > > (GB18918-2002), wherein COD is below 50mg/L, ammonia nitrogen is below 5mg/L, total nitrogen is below 15mg/L, and total phosphorus is below 0.5mg/L.
The above-mentioned description to embodiment is can understand and apply the invention for ease of those skilled in the art.Person skilled in the art obviously can easily make various modifications to these embodiment, and General Principle described herein is applied in other embodiment and needn't passes through performing creative labour.Therefore, the invention is not restricted to the embodiment here, those skilled in the art are according to announcement of the present invention, and not departing from the improvement that category of the present invention makes and revise all should be within protection scope of the present invention.
Claims (6)
1. the multistage terrace-type vertical flow constructed wetland sewage treatment method of combined stuffing, it is characterized in that: the method comprises the following steps: after the sanitary sewage precipitation after secondary biochemical treatment, enter in the multistage terrace-type vertical current constructed wetland of combined stuffing formation, water quality is purified;
Described combined stuffing is first step wetland: the large gravel that particle diameter is 15-18mm; Second stage wetland: the little gravel that particle diameter is 8-10mm; Third stage wetland: the little gravel that the large gravel that particle diameter is 15-18mm is 8-10mm with particle diameter mix gravel, large gravel and pebble stone volume ratio are 1:1; Fourth stage wetland: the bamboo charcoal that the little gravel that particle diameter is 8-10mm and particle diameter are 3mm, both proportional ranges are 1:1～1:3.
2. the multistage terrace-type vertical flow constructed wetland sewage treatment method of combined stuffing according to claim 1, it is characterized in that: described multistage terrace-type vertical current constructed wetland long-width ratio is 1:1.5～1:3, have 4 grades of wetland device series operations, between every grade, drop height is 400-800mm.
3. the multistage terrace-type vertical flow constructed wetland sewage treatment method of combined stuffing according to claim 1, is characterized in that: the combinations of plant that described multistage terrace-type vertical current constructed wetland is used is first step wetland: reed; Second stage wetland: Canna generalis Bailey; Third stage wetland: Herba Bidentis Bipinnatae; Fourth stage wetland: calamus.
4. the multistage terrace-type vertical flow constructed wetland sewage treatment method of combined stuffing according to claim 1, is characterized in that: described combined stuffing layer thickness is 50～80cm.
5. according to the multistage terrace-type vertical flow constructed wetland sewage treatment method of the combined stuffing described in claim 1 or 3, it is characterized in that: described first step wetland, second stage wetland, third stage wetland and fourth stage wetland are divided into inhalant region, wetland is processed main unit district, exhalant region; Current enter inhalant region by water inlet pipe (1), then by water distributor (2), vertically enter into wetland and process main unit district, then flow into exhalant region by perforation rising pipe (3).
6. the multistage terrace-type vertical flow constructed wetland sewage treatment method of combined stuffing according to claim 1, is characterized in that: described sanitary sewage residence time in multistage terrace-type vertical current constructed wetland is 2～5 days.
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| CN201210068327.3A CN102583764B (en) | 2012-03-15 | 2012-03-15 | Combined packing multistage terrace type vertical flow constructed wetland sewage treatment method |
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| CN201210068327.3A CN102583764B (en) | 2012-03-15 | 2012-03-15 | Combined packing multistage terrace type vertical flow constructed wetland sewage treatment method |
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| CN102887590A (en) * | 2012-11-09 | 2013-01-23 | 四川四通欧美环境工程有限公司 | Grading root zone sewage treatment ecological constructed wetland system |
| CN103351080A (en) * | 2013-07-02 | 2013-10-16 | 贵州师范大学 | Purification method for rural domestic sewage and stepped sewage percolation purification system |
| CN103359881B (en) * | 2013-07-24 | 2014-12-17 | 中国科学院亚热带农业生态研究所 | Method for reducing and controlling wastewater pollution of pig farm |
| CN112499881A (en) * | 2020-09-08 | 2021-03-16 | 桂林理工大学 | Wetland treatment method for domestic sewage in terrace region |
| CN114656037A (en) * | 2020-12-23 | 2022-06-24 | 广州怡境景观设计有限公司 | Terrace wetland rain sewage purification system |
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| CN100569670C (en) * | 2007-05-14 | 2009-12-16 | 华南农业大学 | The method for the treatment of sewage by composite vertical down flow artificial wet field and treatment system thereof |
| US8021551B2 (en) * | 2008-03-27 | 2011-09-20 | Mark Harrison | Eco-treatment system |
| CN102030443A (en) * | 2009-09-25 | 2011-04-27 | 宁波大学 | Terrace type composite vertical flow forest wetland and domestic sewage treatment method thereof |
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