CN1587103A - Filter material having phosphor adsorbing and biological membrane function and its preparing method - Google Patents

Abstract

The filter material with phosphor adsorbing and biological membrane hanging functions is prepared with flyash with CaO content of 5-20 % as material, and through stoving, sieving, mixing with water and small amount of curing agent via stirring, pelletizing in a high speed turntable pelletizer, and naturally cured for 2-7 days while spraying water to maintain the water content of 10-40 % to form the spherical filter material. The filter material has irregular rough surface with microporous structure for biological membrane to grow easily. The filter material has the advantages of fast absorbing phosphate in great amount, and eliminating SS, BOD and other soluble organic matter from sewage. The present invention may be used widely in water treating industry, especially in directly purifying rich nutrients water.

Description

Have both filtrate of phosphorus absorption and biological membrane function and preparation method thereof

Technical field

The present invention relates to a kind of filtrate that is used for enriched surface water or advanced treatment of wastewater and preparation method thereof, relating to more specifically with flyash is filtrate of efficient phosphorus absorption of having both of raw material and biological membrane function and preparation method thereof, be suitable for lake and river eutrophic water, city domestic sewage and various industrial wastewater treatment system, belong to the environmental engineering technical field of sewage.

Background technology

In recent years, the phenomenon of large-area body eutrophication has all appearred in basins such as the Taihu Lake of China, Dian Chi.Can cause the blue-green algae outburst when eutrophication is serious, cause water quality sharply to descend, hydrocoles mass mortalities such as water fish shrimp cause living standard of urban and rural population water difficulty simultaneously.Meanwhile, the fast development of power industry has in recent years caused increasing sharply of flyash quantity discharged.At present, the mode of flyash disposal is based on the ash disposal area stacking.According to measuring and calculating, the construction cost of the large-scale ash disposal area of general power plant is all about in the of 100,000,000 yuan, but also taken a large amount of soils, and environment is produced huge potential hazard.In China's comprehensive utilization rate of coal ash only is about 40%, substantially all is applied to construction industry, to produce the dopant in light building material such as flyash brick, lytag and concrete, the mortar.But this type of flyash production cost of products height, added value is low, is unfavorable for extensive popularization.Therefore,, press for to find and can improve the flyash added value of product for solving the problem of complex utilization of flyash, and technology new purposes with low cost.

Show that according to the study several big main eutrophic lakes of China are the phosphorus restricted type, promptly can prevent and treat the generation of body eutrophication by cutting down exogenous phosphorus and endogenous phosphorus.Numerous discovering both domestic and external, the phosphorus during flyash can be used for disposing of sewage can be specially adapted to big flow, the improvement of the lake river water of low pollution concentration by a large amount of phosphoric acid salt of materialization effect absorption in the extremely short time.Pertinent literature as: 1, modified coal ash is removed phosphorus and the colourity (Chinese water supply and drainage .2002.18 (10) .49-51) in the antibiotic waste water.2, flyash Study on Removal of Phosphorus in Wastewater (Shanghai environmental science .2000.19 (1) .33-34).Utilize flyash to handle not only processing efficiency height of phosphorus, and promoted recovery of resources.But find that in application process flyash water-permeable extreme difference be cotton-shaped behind the chance water and be difficult to precipitation, and the pH value significantly raises in the water outlet, these shortcomings have directly had influence on the feasibility of utilizing flyash to dispose of sewage.It is main raw material with industrial residue steel-making red mud, flyash that Chinese invention patent CN 1380127A has announced a kind of, the porous ceramic grain that high temperature sintering forms, and its surface growth microbial film can be in order to remove the organic pollutant in the water.But for the balling-up that bonds, added the impurity such as clay, red mud of a large amount of no remarkable dephosphorization usefulness in this haydite making processes, accounted for the 30%-60% of raw material.Required ultimate compression strength and stability when being used for sewage disposal for this product is reached, adopted the way of 800 ℃ of-1100 ℃ of high temperature sinterings, complex process not only, sintering cost height, and in sintering process, cause a large amount of losses of phosphorus adsorption surface, be not suitable for the phosphorus of removing in the sewage.Chinese invention patent CN1486940A disclosed " compounded mix that is used for the sewage disposal biomembrane process " is though need not sintering, but in order to bond balling-up and reach enough intensity, must add the cement bond agent of 35%-45%, thereby cause a large amount of losses of phosphorus adsorption surface, be only applicable to remove organism and ammonia nitrogen in the sewage.

Summary of the invention

The objective of the invention is at the deficiencies in the prior art, a kind of filtrate that has both phosphorus absorption and biological membrane function and preparation method thereof is provided, process of preparing filter material is simple, with low cost, the filtrate that makes can keep original state flyash can be fast, and the advantage of adsorbing phosphorus in a large number has simultaneously the ordinary filter microbial film of can growing again, remove the SS (solid suspended particles) in the sewage, the function of BOD (biochemical oxygen demand (BOD)).

For realizing this purpose, the main raw material that the present invention adopts is a flyash, belongs to the silicates material, contains the glass microballon that a large amount of burnings at high temperature back generates, and himself has certain gelling.According to these characteristics, the solidifying agent that the flyash of manually allotment is mixed and adds trace with water, and do not add cementing agent or binding agents such as cement, clay, impel the inner crystal seed that generates of mixture by specific stirring technique, and generation gradually " is similar to the hydration reaction that cement forms ", it is higher to can be made into intensity, anti-washing away, constitutionally stable filtrate.The filtrate of making is the surface imperfection particulate state of nearly ball-type, and surface irregularity and have microvoid structure is easy to the microbial film of growing.

The composition of filtrate of the present invention and consumption (weight part) are as follows:

The flyash of artificial allotment: 100

Solidifying agent: 0.5-5

Water: 20-30

The CaO content requirement of the flyash that the present invention is used manually is formulated to weight percent between 5-20%, and solidifying agent is mainly the silicates material, as water glass, Calucium Silicate powder etc.

The preparation method of filtrate of the present invention is as follows:

(1) the flyash oven dry that will manually allocate is sieved and stage treatment, obtains the above raw material of 200 orders.

(2) getting weight part is 100 flyash, and adding weight part is the solidifying agent of 0.5-5, and mixing the back, to spray weight part be the water of 15-25, constantly provides power to stir.Mixture is loose, thick before stirring; Stir back initial period (5-10 minute) and form the solid crystal seed earlier, though the loose no longer thickness of mixture this moment; Add weight part afterwards again and be 5 water, continue to stir, rely on the wicking action of water to make between crystal seed and the crystal seed and closely contact, crystal seed is grown up gradually; Become densification until observing mixture, the lumps of consolidation promptly places 0.5m highly to land when not broken, thinks to stir and finishes.

(3) mixture is dropped into granulating and forming in the high speed rotating plate tablets press.

(4) with above-mentioned shaped granule natural curing 2-7 days at normal temperatures, must be in this process every 7-12 hour spray water, to keep the particle water content between 10%-40%.The purpose of maintenance is to impel the inner generation of filtrate " hydration reaction when being similar to cement formation ", to improve grain compressive strength, guarantees the weather resistance when it is used for water treatment.

Filtrate of the present invention is the surface imperfection particulate state of nearly ball-type, and surface irregularity and have microvoid structure is easy to the microbial film of growing, and ultimate compression strength is 1.5-4Mpa, and proportion is 1.4-1.5kg/cm ³, particle diameter is 0.5-5mm.Recording the phosphorus loading capacity according to Langmuir method commonly used is 4-10mg/g.

Filtrate after the use can adopt normal sintering method baking ceramsite, is widely used in construction industry as the high-strength light building materials, also can be used as biological ceramic particle and is used to handle little source of pollution water, realizes recovery of resources.

Innovation part of the present invention is that the phosphorus characteristics are inhaled in the flyash materialization and the ordinary filter function combines, both kept fly ash highly to remove the performance of pollution substance phosphorus, the Ash Water Separator difficulty that runs into when efficiently solving the flyash dephosphorization again, the difficult problem that pH is too high, the gained filtrate can be widely used in water treatment field, is specially adapted to the direct purification eutrophication water.

Advantage of the present invention and active effect are embodied in: 1. the phosphorus loading capacity of this filtrate is 4-10mg/g, the very high filler such as the heaving shales of phosphorus loading capacity of generally acknowledging is 0.971mg/g at present, slag is below the 1.5mg/g, general phosphorus sorbing material mostly below 1mg/g, only is about 1/10th of this filtrate then.2. this filtrate is exceedingly fast to the removal speed of phosphorus in the water, reaches 0.25mg/ (kg * s), 90% treatment effect was nearly just arranged duration of contact in a minute the soonest.And generally all will just have removal effect the duration of contact of similar dephosphorization filtrate more than 1 hour, as be used for the dephosphorization filler wollastonite of artificial swamp duration of contact must be more than 2 hours.3. this filtrate is a particulate state, meets water and does not dissolve, and does not exist to be difficult to sedimentary problem; Its rate of permeation reaches 0.272cm/s, and original state flyash only is 0.00869cm/s, surplus rate of permeation improves 30 times; And pH is stabilized in about 9 in the water outlet, a difficult problem that has run into when successfully having solved the flyash dephosphorization.4. in the materialization planar water, in the phosphorus, have ordinary filter growth microbial film concurrently, remove the function of SS and BOD.5. solve the handling problems of flyash effectively, reclaim simultaneously and regeneration resource.6. as the flyash wide material sources of raw material, be not subjected to the region, the restriction in season, and technology is quite simple, and cost is extremely cheap, the added value of product height.7. the filtrate composition is single, still can be used for building materials such as baking ceramsite, light wall brick after using.

Embodiment

Below by specific embodiment technical scheme of the present invention is further described.Enforcement of the present invention is not limited to following examples.

Embodiment 1

Raw material adopts the Shanghai fly ash in electric power plant, and its composition consists of: CaO manually is formulated to 19.3%, and MgO is 7.6%, Fe ₂O ₃Be 8.8%, Al ₂O ₃Be 16.7%, SiO ₂Be 46.9%.With 100 grams is that 200 purpose flyash and solidifying agent water glass 0.5 restrain the input stirred vessel after screening, sprays 15 gram water behind the uniform mixing, waits to stir and sprays 5 gram water after 5 minutes again, continues to be stirred to the formation densification, the agglomerate of consolidation.Place after tested 0.5m highly land not broken after, again mixture is dropped into granulating and forming in the high speed rotating plate tablets press.Natural curing is 2 days after the moulding, therebetween every 7 hours spray water, to keep the particle water content 10%.The filtrate ultimate compression strength of making is 4Mpa, and proportion is 1.44g/cm ³, grain diameter is between 1-5mm.Recording the phosphorus loading capacity according to Langmuir method commonly used is 10mg/g.

Utilize particle diameter that above-mentioned technology makes to be the filtrate of the 0.5mm filler Removal of Phosphorus in Wastewater as fixed bed, 1 minute duration of contact, phosphorus concentration is 5mg/L before handling, and handling the back phosphorus concentration is 0.5mg/L, and clearance reaches 90%.

The particle diameter that utilizes above-mentioned technology to make is handled sanitary sewage for the filtrate of 5mm as the filler of fixed bed, a large amount of microbial film of 2 week of domestication back filter material surface growth.Hydraulic detention time is 4 hours during operation, and sewage BOD concentration is 120mg/L before handling, and handling back BOD concentration is 17mg/L, and clearance reaches 86%.

The particle diameter that utilizes above-mentioned technology to make is handled landscape water for the filtrate of 3mm as the filler of fixed bed, a large amount of microbial film of 2 week of domestication back filter material surface growth.Hydraulic detention time is 40min during operation, sewage phosphorus concentration is 0.7mg/L before handling, BOD concentration is 7mg/L, ammonia nitrogen concentration is 3mg/L, and handling the back phosphorus concentration is 0.1mg/L, and BOD concentration is 1.6mg/L, ammonia nitrogen concentration is 1mg/L, tp removal rate reaches 86%, and the BOD clearance reaches 77%, and ammonia nitrogen removal frank reaches 67%.

Utilize the above-mentioned filtrate sintering ceramsite of absorption when saturated, 1100 ℃ of sintering temperatures, sintering 30 minutes, product intensity 8Mpa, the proportion 1400kg/m of reaching ³, unit weight 710kg/m ³This product can be used as the high-strength light building materials and is widely used in construction industry, also can be used as biological ceramic particle and is used to handle little source of pollution water.

Embodiment 2

Raw material adopts the Xiamen fly ash in electric power plant, and its composition consists of: CaO manually is formulated to 5.3%, and MgO is 3.8%, Fe ₂O ₃Be 7.9%, Al ₂O ₃Be 25.8%, SiO ₂Be 54.9%.With 100 grams is that 200 purpose flyash and solidifying agent Calucium Silicate powder 3 restrain the input stirred vessels after screening, sprays 25 gram water behind the uniform mixing, waits to stir and sprays 5 gram water after 10 minutes again, continues to be stirred to the formation densification, the agglomerate of consolidation.Place after tested 0.5m highly land not broken after, again mixture is dropped into granulating and forming in the high speed rotating plate tablets press.Natural curing is 7 days after the moulding, therebetween every 12 hours spray water, to keep the particle water content 40%.The filtrate ultimate compression strength of making is 1.5Mpa, and proportion is 1.43g/cm ³, grain diameter is between 1-5mm.Recording the phosphorus loading capacity according to Langmuir method commonly used is 5mg/g.

Embodiment 3

Raw material adopts Shenzhen fly ash in electric power plant, and its composition consists of: CaO manually is formulated to 15.2%, and MgO is 1.8%, Fe ₂O ₃Be 2.7%, Al ₂O ₃Be 25.4%, SiO ₂Be 51.1%.With 100 grams is that 200 purpose flyash and solidifying agent Calucium Silicate powder 1.5 restrain the input stirred vessels after screening, sprays 20 gram water behind the uniform mixing, waits to stir and sprays 5 gram water after 8 minutes again, continues to be stirred to the formation densification, the agglomerate of consolidation.Place after tested 0.5m highly land not broken after, again mixture is dropped into granulating and forming in the high speed rotating plate tablets press.Natural curing is 5 days after the moulding, therebetween every 8 hours spray water, to keep the particle water content 15%.The filtrate ultimate compression strength of making is 2Mpa, and proportion is 1.43g/cm ³, grain diameter is between 1-5mm.Recording the phosphorus loading capacity according to Langmuir method commonly used is 6.5mg/g.

Claims (3)

1, a kind of preparation method who has both the filtrate of phosphorus absorption and biological membrane function is characterized in that comprising the steps:

(1) is the flyash oven dry of 5-20% with the CaO weight percent content, sieves and handle the back as raw material;

(2) getting weight part is 100 raw material powder coal ash, adding weight part is the solidifying agent of 0.5-5, mixing the back, to spray weight part be the water of 15-25, stirs that to add weight part after 5-10 minute again be 5 water, continues stirring becomes densification, consolidation until mixture lumps;

(3) mixture is dropped into granulating and forming in the high speed rotating plate tablets press;

(4) with above-mentioned shaped granule natural curing 2-7 days at normal temperatures, water spray obtains filtrate to keep the particle water content at 10-40%.

2, the preparation method who has both the filtrate of phosphorus absorption and biological membrane function as claimed in claim 1 is characterized in that described solidifying agent is a silicates, comprises water glass or Calucium Silicate powder.

3, a kind of filtrate that has both phosphorus absorption and biological membrane function that adopts the method preparation of claim 1 or 2, it is characterized in that filtrate is the surface imperfection particulate state of nearly ball-type, surface irregularity and have microvoid structure, filtrate ultimate compression strength is 1.5-4Mpa, proportion is 1.4-1.5kg/cm ³, particle diameter is 0.5-5mm, the phosphorus loading capacity is 4-10mg/g.