CN101229946A - Biological aerated filter filtering material for treating sewage and preparation method thereof - Google Patents

Abstract

The invention essentially relates to a filter material for treating sewage, in particular to relate to a filtering material used in the sewage process technique of aeration biology filtering pool. The filtering material of sewage process of the aeration biology filtering pool is characterized in that the components of the raw material of the filtering material consists of by fly ash of 60 to 75 percent, portland cement of 10-20 percent, quick lime of 10-20 percent, gypsum 3-5 percent and degreasing aluminum powder of 0.06-0.08 percent. The preparation includes the following steps of pulping, stirring, pouring, cutting forming and ball milling. Under the optimal proportion of the air and water and the optimal water force load, the life sewage is treated by the aeration biology filtering pool with adding the fly ash to the gas concrete particle. When the average concentration of the water inlet is 176mg/L, the average removal rate of the CODis 75.3 percent, the average concentration of water inlet is 42.7mg/L, the average removal rate of the NH3-N is 96.4 percent, the average concentration of the water outlet is 0.87mg/L which meets the GB18918-2002 grade A standard of the sewage discharging.

Description

Filtrate that BAF is disposed of sewage and preparation method thereof

Technical field:

The present invention relates generally to a kind of filtrate of disposing of sewage, and relates in particular to the filtrate that uses in the BAF sewage treatment.

Background technology:

In the BAF sewage treatment, by the big I of density filtrate is divided into density greater than 1 with less than 1 two kinds, the main raw that is used to make filtrate at present has organic hard materials such as inorganic hard material such as gac, quartz sand, haydite and zeolite and polystyrene, polyethylene, polypropylene, PVC.Most of mineral-type filtrate physical strengths are better relatively, and specific surface area is bigger, are 500～900m as gac ²/ g, zeolite are 10.2～15.0m ²/ g, haydite are 3.1～4.2m ²/ g; But most of inorganic filtrate density is excessive, is 2.5～2.7g/cm as quartz sand ³, zeolite is 2.0～2.3g/cm ³, haydite is 2.5～2.6g/cm ³, cause in technology operation and the backwash process energy consumption relatively large; Organic filtrate density is moderate, is 1.38g/cm as plastic filler ³, fibrous nodules is 1.38g/cm ³, Pall ring is 0.45～0.67g/cm ³, be the filtrate that has development prospect at present, but most of organic filtrate specific surface area is less relatively and cost an arm and a leg, be 66～350m as Pall ring ²/ m ³, cascade ring is 63～108m ²/ M ³, the polyvinyl chloride honeycomb padding is 99～236m ²/ m ³, cause whole process efficiency to reduce and the equipment cost rising.

Recently developed a kind of light porous Biohaydite filter material, it be a kind of be main raw material with clay, steelworks steel-making red mud, add certain pore-forming material,, be prepared into surface irregularity, specific surface area is big, voidage is high, appearance is hard haydite through granulating and forming, high temperature sintering.It is shaped as sphere, and particle diameter is 4～6mm, and apparent density is 1.4～2.2g/cm ³, specific surface area is 9.2m ²/ g is to study and use the most general biofilter material now, and its price is higher.

Summary of the invention:

The filtrate that provides a kind of BAF to dispose of sewage to the deficiencies in the prior art part is provided, this filtrate cost is low, filtrate density is moderate, the surface irregularity porous, the aperture of hole becomes Gradient distribution, the impact resistance that particle is soaked in the water can not reduce, and does not contain the deleterious material of people, microorganism and ecotope, sewage treating efficiency height.

Purpose of the present invention can be by realizing by the following technical solutions: the filtrate that a kind of BAF is disposed of sewage, described filtrate raw material are formed and are included flyash 60～75%, silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5%, degreasing aluminium powder 0.06～0.08%.

The filtrate that described BAF is disposed of sewage, described filtering material particle particle diameter is 4～12mm.

The preparation method of the filtrate that a kind of BAF is disposed of sewage, its preparation process is:

1) slurrying: earlier silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5% are mixed, flyash 60～75% addings are mixed again, add water slurrying, ratio of water to material is 0.6～0.7;

2) stir: the slip that step 1 is made stirs and adds degreasing aluminium powder 0.06～0.08% again behind 30～40min and stir 30～40s:

3) cast: be under 25～70 ℃ the condition, in mould, to pour into a mould slip, the quiet 2～3h that stops in temperature;

4) excision forming; Use cutting machine that pour mass is cut into the square that the length of side is 5～14mm;

5) high-pressure steaming and cultivating: 12～13 normal atmosphere, temperature are 185～200 ℃ in autoclave, keep 8h;

6) ball milling.

The preparation method of the filtrate that described BAF is disposed of sewage, described step also includes: being step 5 after step 3, is following steps after step 5:

Crushing and screening: above step is made the fragmentation of powder ash air-entrained concrete piece, and corner angle are removed in barreling, screening, and making its granularity is 4～12mm.

Composition analysis result of the present invention:

The powder ash air-entrained concrete particle surface is seen Fig. 1 through scanning electron microscope energy spectrogram, and show that the contained main chemical elements mass percent of powder ash air-entrained concrete particle is: Ca is 42.6%～53.2%; Si is 15.3%～21%; Al is 6.3%～6.4%; Fe is 2.5%～4.6%; K is 1.7%～2.1%; Mg is 0.6%～0.7%.

Checking the present invention uses the technical scheme of usefulness: the useless piece in the product corner in the powder ash air-entrained concrete building block production process, powder ash air-entrained concrete building block buildings waste are broken into required particle diameter particle, it is loaded in the pillar BAF then, feed clear water operation for some time to wash the foreign material of filter material surface, cleaning finishes and carries out indoor biofilm and sanitary sewage disposal test again, determines pollutant removal under the optimum operating condition.

This powder ash air-entrained concrete particle is irregularly shaped, and grain diameter is 4～12mm, and specific surface area is 9.0～10.0m ²/ g, apparent density is 1.3～1.5g/cm ³Use scanning electron microscopic observation powder ash air-entrained concrete particle surface to have many holes, hole is distribution gradient roughly, the maximum diameter of hole is that 300～500um, minimum-value aperture are 1～10um, and filter material surface small holes edge of the present invention and the many structural holes of outside formation.

In the test run stage, directly feed the preliminary sedimentation tank water outlet of sanitary sewage disposal factory.Elder generation is hydraulic load (15.36m fixedly ³/ m ²D), carry out long run test with different gas-water ratios (1/4,1/2,1,2,4,8) and obtain a result and see Fig. 2, according to COD and NH ₃The highest average removal rate of-N determines that best gas-water ratio is 2; Fixedly gas-water ratio is 2 then, with different hydraulic loads (3.84,7.68,15.36,30.72 and 61.44m ³/ m ²D) the continuation test is obtained a result and is seen Fig. 3, according to COD and NH ₃The highest average removal rate of-N determines that best hydraulic load is 15.36m ³/ m ²D.Gas-water ratio, hydraulic load at best of breed are respectively 215.36m ³/ m ²D moves to obtain a result down and sees Fig. 4, and organic loading remains on 4.23～5.04kgCOD/m ³Between the d, COD, NH ₃-N average removal rate reaches 75.3%, 96.4% respectively, COD, NH in the water outlet ₃-N mean concns is respectively 42.7mg/L, 0.87mg/L.

Below be experiment effect table of the present invention, further specify effect of the present invention.

COD, NH under the different gas-water ratios of table 1 ₃-N clearance

Time (d)	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
																	Gas-water ratio	0.25	0.25	0.5	0.5	0.5	1	1	1	2	2	2	4	4	4	8	8
COD clearance (%)	61.5	23.8	75	65	73	65	77	71	80	75	71	72	73.1	79	72.7	73.9
																	NH 3-N clearance (%)	88.2	88.8	100	93	99	100	99	93	98.4	98.2	92.5	93.6	91	92.8	95.3	92.3

COD, NH under the different hydraulic loads of table 2 ₃-N clearance

Time (d)	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
																Hydraulic load (m 3/m 2·d)	3.84	3.84	3.84	7.68	7.68	7.68	15.36	15.36	15.36	30.72	30.72	30.72	61.44	61.44	61.44
COD clearance (%)	73.1	73.7	78.3	64.7	76.9	77.2	80	75	71	72	76.5	69	64	50	29.6
																NH 3-N clearance (%)	79.7	93.7	96	95	95.6	93.8	98.4	98.2	92.5	93	92.5	88	95	89.7	87.1

Pollutant removal under the different influent concentrations of table 3

Time (d)	1	2	3	4	5	6
							Water inlet COD (mg/L)	160	168	200	290	296	312
Water outlet COD (mg/L)	40	48	40	50	68	64
							COD clearance (%)	75	71	80	82.8	77	79.5
Water inlet NH 3-N(mg/L)	22.3	26	25	23.7	29.6	28.8
							Water outlet NH 3N(mg/L)	0.4	1.95	0.4	0.69	4.9	2.1
NH 3-N clearance (%)	98.2	92.5	98.4	97.1	83.4	92.7

Filtrate of the present invention has the general characteristic as the BAF filtrate:

A) because inner many enclosed spaces and water wherein segment space more difficult to get access, the apparent density (1.3～1.5g/cm of forming of filtrate of the present invention ³) less;

B) surface irregularity porous, specific surface area are big;

C) be soaked in the water and can continuation harden, so its impact resistance in water can not reduce;

D) its main chemical elements consists of Si, Al, Fe, Ca, K, Mg, does not contain the deleterious material of people, microorganism and ecotope.

The distinct advantages that filtrate of the present invention had:

A) aperture of surface hole defect one-tenth Gradient distribution, and most of hole aperture is about 5um, helps microorganism growth and improves mass-transfer efficiency;

B) surperficial small holes edge and the many structural holes of outside formation, it is fixing to help holding back of microorganism;

C) obtain useless piece in product corner when fly ash aerated building block is produced and the fly ash aerated building block building thing waste, its cost of manufacture be organic filtrate 1/10～1/50, inorganic filtrate 1/2～1/7;

D) be applied to the BAF sewage treatment and can also realize that admittedly useless resource utilization utilizes again.

The invention has the beneficial effects as follows: under best gas-water ratio and hydraulic load condition, use filtrate of the present invention and handle sanitary sewage, when the water inlet mean concns was 176mg/L, the COD average removal rate was 75.3%, and the water outlet mean concns is 42.7mg/L; NH ₃-N average removal rate is 96.4%, and the water outlet mean concns is 0.87mg/L, and sewage discharge GB18918-2002 one-level A standard is satisfied in water outlet.

Description of drawings:

Fig. 1 is filter material surface scanning electron microscope energy spectrogram of the present invention;

Fig. 2 is COD, NH under the different gas-water ratios of the present invention ₃-N clearance change curve;

Fig. 3 is COD, NH under the different hydraulic loads of the present invention ₃-N clearance change curve;

Fig. 4 is intake COD to COD, NH for the present invention ₃The influence curve figure of-N clearance.

Embodiment:

Be described in further detail below in conjunction with the most preferred embodiment shown in the accompanying drawing:

Embodiment 1, and the filtrate that a kind of BAF is disposed of sewage includes flyash 60%, silicate cement 15%, unslaked lime 20%, gypsum 4.94%, degreasing aluminium powder 0.06%, ratio of water to material: 0.7.

The filtrate that described BAF is disposed of sewage, described filtering material particle particle diameter is 4～12mm.

Embodiment 2, and the filtrate that a kind of BAF is disposed of sewage includes flyash 70%, silicate cement 10%, unslaked lime 15%, gypsum 4.92%, degreasing aluminium powder 0.08%, ratio of water to material: 0.7, also added foaming stabiliser and other conditioning agents.

Described starting material should meet following requirement:

1. flyash: should meet " silicate building products flyash " (JC409-1991) I in the standard, requirement of II level flyash, fineness is less than 8%～15% (the 80um square hole sieve tails over).

2. unslaked lime: A-CaO (the efficient oxidation calcium) 50%～65%, MgO＜8%, digestion rate 10～30min, 50～70 ℃ of digestion conditions, fineness＜15% (the 80um square hole sieve tails over).

3. cement: should use silicate cement and ordinary Portland cement

4. gypsum: SO ₃＞40%, fineness＜17% (the 80um square hole sieve tails over)

5. aluminium powder: two kinds of band dried aluminium powder of fat and paste aluminium powders are arranged, its quality is with active aluminium content, the lid water area curve of getting angry is weighed, should meet (GB2084-1980) requirement of national standard " aluminium powder of getting angry ", when using the dried aluminium powder of band fat, also need to use grease-removing agent to remove aluminium powder surface grease, generally use higher fatty acid-oxyethane (peregal), fourth sodium dinaphthalenesulfonate (drawing back powder), tensio-active agents such as synthetic detergent come degreasing.

6. foaming stabiliser: use soap firefly powder, soluble oil, oxidized paraffin wax soap etc. are arranged.

7. other conditioning agents: can use conditioning agents such as caustic soda, sodium bicarbonate in order to improve raising rate, in order to delay to begin the time of getting angry, it is excessive to avoid getting angry, and can use water glass conditioning agent etc.

Embodiment 3, and the filtrate that a kind of BAF is disposed of sewage includes flyash 75%, silicate cement 10%, unslaked lime 10%, gypsum 4.96%, degreasing aluminium powder 0.06%, ratio of water to material: 0.6.

Embodiment 4,

Press the proportioning of embodiment 1-3, the preparation method is as follows:

1) slurrying: earlier silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5% are mixed, flyash 60～75% addings are mixed again, add water slurrying, ratio of water to material is 0.6～0.7;

2) stir: the slip that step 1 is made stirs and adds degreasing aluminium powder 0.06～0.08% again behind 30～40min and stir 30～40s;

3) cast: be under 25～70 ℃ the condition, in mould, to pour into a mould slip, the quiet 2～3h that stops in temperature;

4) excision forming; Use cutting machine that pour mass is cut into the square that the length of side is 5～14mm;

5) high-pressure steaming and cultivating: 12～13 normal atmosphere, temperature are 185～200 ℃ in autoclave, keep 8h;

6) ball milling.

Embodiment 5:

By the proportioning of executing routine 1-3, the preparation method is as follows:

1) slurrying: earlier silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5% are mixed, flyash 60～75% addings are mixed again, add water slurrying, ratio of water to material is 0.6～0.7;

2) stir: the slip that step 1 is made stirs and adds degreasing aluminium powder 0.06～0.08% again behind 30～40min and stir 30～40s;

3) cast: be under 25～70 ℃ the condition, in mould, to pour into a mould slip, the quiet 2～3h that stops in temperature;

4) high-pressure steaming and cultivating: 12～13 normal atmosphere, temperature are 185～200 ℃ in autoclave, keep 8h;

5) crushing and screening: above step is made the fragmentation of powder ash air-entrained concrete piece, and corner angle are removed in barreling, screening, and making its granularity is 4～12mm.

Embodiment 6: the filtrate that a kind of BAF is disposed of sewage, use crusher useless piece in the product corner in the powder ash air-entrained concrete building block production process or fly ash aerated building block building thing waste are broken into small-particle, using sieve aperture then is two kinds of sieve of 4mm and 12mm, gets that part of particle that can see through the 12mm sieve aperture and be retained down by 4mm sieve aperture sieve and is required filtrate.

In filtrate uses, also need pass through filtrate biofilm process, during biofilm, concentrate active sludge with sewage work's second pond and be made into activated sludge solutions, biological aerated filter process is inoculated.Keep flow 6L/h, aeration rate 8L/h, with the refuse landfill sanitary sewage, ooze drop liquid, clear water and mix by a certain percentage successively and intermittently feed BAF, ratio is followed successively by: 29: 1: 0,28: 2: 12,27: 3: 15.At certain proportion continuously under the situation of operation,, change next ratio successively when the COD processing rate in the water outlet reaches when stablizing.The basicly stable biofilm that shows about 60% of COD processing rate finishes in the final blending sewage.After can clearly observing biofilm, filter material surface of the present invention adheres to the gauze bio film of one deck densification, is mainly the microbial film that nitrifier forms by analysis.

Claims (4)

1. filtrate that BAF is disposed of sewage is characterized in that: described filtrate raw material is formed and is included flyash 60～75%, silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5%, degreasing aluminium powder 0.06～0.08%.

2. the filtrate that BAF as claimed in claim 1 is disposed of sewage is characterized in that: described filtering material particle particle diameter is 4～12mm.

3. the preparation method of the BAF filtrate of disposing of sewage, its preparation process is:

1) slurrying: earlier silicate cement 10～20%, unslaked lime 10～20%, gypsum 3～5% are mixed, flyash 60～75% addings are mixed again, add water slurrying, ratio of water to material is 0.6～0.7;

2) stir: the slip that step 1 is made stirs and adds degreasing aluminium powder 0.06～0.08% again behind 30～40min and stir 30～40s:

3) cast: be under 25～70 ℃ the condition, in mould, to pour into a mould slip, the quiet 2～3h that stops in temperature;

4) excision forming; Use cutting machine that pour mass is cut into the square that the length of side is 5～14mm;

5) high-pressure steaming and cultivating: 12～13 normal atmosphere, temperature are 185～200 ℃ in autoclave, keep 8h;

6) ball milling.

4. the preparation method of the filtrate that BAF as claimed in claim 3 is disposed of sewage is characterized in that: described step also includes: being step 5 after step 3, is following steps after step 5:

Crushing and screening: above step is made the fragmentation of powder ash air-entrained concrete piece, and corner angle are removed in barreling, screening, and making its granularity is 4～12mm.

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