CN101838084A - Biochemical regulation and treatment process for sewage of urban domestic garbage transfer station - Google Patents

Abstract

The invention relates to a biochemical regulation and treatment process for the sewage of an urban domestic garbage transfer station, which comprises the following procedures that: the sewage of the garbage transfer station flows into a biochemical regulation tank to carry out an anaerobic reaction, oil removal and sand setting are realized, and an organic load is lowered; then, the sewage flows into a coagulative precipitation tank after the sewage is mixed with an added composite flocculating agent, and suspended matters and grease are removed; afterwards, the sewage flows into an acidification tank, and ferrous sulfate and an acid solution are added to enable the pH value of water to be 2 to 4; the acidified water flows into an oxidation tank and carries out an oxidation reaction with an oxidant, the ferrous sulfate is oxidated into ferric iron, and an organic pollutant is removed; then, the water flows into a neutralization tank and carries out a neutralization reaction with lye, and the pH value is regulated to be 7 to 8; and finally, the water flows into an inclined-plate sedimentation tank, and the residual ferrous sulfate and the residual ferric iron are settled to obtain the purified water. The process has the characteristic and effect of removing more than 70 percent of chemical oxygen demand, more than 95 percent of suspended matters and more than 80 percent of grease in the sewage of the urban garbage transfer station.

Description

A biochemical regulation and treatment process for municipal solid waste transfer station sewage

technical field

The invention relates to a sewage treatment process, in particular to a sewage biochemical regulation treatment process of a city life garbage transfer station.

Background technique

As a joint point connecting the source of waste generation and the terminal disposal system, the municipal solid waste transfer station is an important hub in the municipal solid waste collection and transportation system. Secondary pollution such as sewage generated during the operation of transfer stations has become a hot spot of public concern. The main sources of sewage generated by the garbage transfer station are: leachate produced during garbage compression; washing sewage from vehicles, equipment, and road surfaces; domestic sewage from employees. The amount of sewage produced by the transfer station is relatively small, and it shares the characteristics of high pollutant concentration, complex composition, and large changes in water quality and quantity with landfill leachate.

The sewage of the transfer station is usually a khaki or brown-red liquid, accompanied by a strong stench; the sewage of the transfer station has many impurities, high content of suspended solids, and usually has large garbage fragments; the organic load is high and has a strong stench; the sewage The pH value is about 6, which is acidic and has a strong corrosive effect on equipment and pipelines; the sewage at the transfer station also contains a large amount of oil, which not only easily blocks the pipelines, but also seriously affects the subsequent treatment of urban sewage treatment plants. Compared with the water quality standards of sewage discharged into urban sewers, the main pollution indicator COD (chemical oxygen demand) exceeds the standard by dozens or even hundreds of times, which is an important urban point source pollution that needs to be solved urgently.

The sewage treatment method of the existing garbage transfer station is to take over and discharge it into the urban sewage treatment plant, and mix it with other urban sewage for joint treatment. The outstanding problem is: due to the high concentration of pollutants in the sewage of the transfer station, it will cause an impact load on the sewage treatment plant, and even affect the normal operation of the sewage treatment plant in severe cases. The operation will have adverse effects; problems such as chromaticity and odor are difficult to solve by conventional methods. Therefore, efficient and rapid pretreatment of sewage at the transfer station is the key link to solve the problem of sewage treatment at the garbage transfer station.

Contents of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a biochemical regulation treatment process for municipal solid waste transfer station sewage, which has the characteristics of flexible, fast and low-cost treatment of municipal solid waste transfer station sewage. Transparent and clear without turbidity, no obvious smell, good sensory properties.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A biochemical regulation and treatment process for municipal solid waste transfer station sewage, including the following process flow:

Step 1: The sewage 1 of the municipal waste transfer station first flows into the biochemical regulating tank 2 in the form of a baffle plate, and undergoes anaerobic reaction to realize oil separation, sand settling and reduction of organic load;

The second step: after dissolving the composite flocculant 10 with a ratio of 90% of the total weight of polyaluminum chloride and 10% of polyacrylamide at a dose of 400mg-600mg/L, it passes through the gap between the nozzle of the water injector and the throat. The composite flocculant 10 is inhaled by vacuum suction, and injected into the water regulated by the biochemical adjustment tank 2 at the same time. After mixing, it flows into the coagulation sedimentation tank 3, removes suspended solids and grease, and realizes flocculation and sedimentation to form sludge. The sludge uses gravity The way of sludge discharge is discharged through the sludge valve on the coagulation sedimentation tank 3;

The third step: After the water after removing suspended solids and grease flows into the acidification pool 4, add a concentration of 10% ferrous sulfate 14 solution to the acidification pool 4 by a dose of 0.05-0.08mol/L, and add the composition by weight The acid solution 11 of 10% dilute sulfuric acid or dilute hydrochloric acid ensures that the pH value required for the subsequent chemical oxidation is between 2-4;

The fourth step: the water after the acidification flows into the oxidation pool 5, and the oxidant 12 whose composition is 27.5% hydrogen peroxide by weight is added to the oxidation pool 5 to carry out the oxidation reaction. The molar ratio of hydrogen peroxide and ferrous sulfate 14 is 1-5, and the hydraulic retention time is 2 -4 hours, after the oxidation reaction, ferrous sulfate 14 is oxidized to ferric iron, realizing the oxidation and removal of high-concentration organic pollutants, and eliminating the color and odor of sewage;

Step 5: the water after the oxidation reaction flows into the neutralization tank 6, and the lye 13 whose composition is 10% sodium hydroxide solution by weight is added to carry out the neutralization reaction to adjust the pH value to 7-8;

Step 6: Finally, it flows into the inclined plate sedimentation tank 7 to precipitate unreacted ferrous sulfate 14 and ferric iron to obtain purified water 8 and discharge it into the municipal pipe network 9 .

Because the present invention has designed biochemical adjustment pond 2, coagulation sedimentation pond 3, acidification pond 4, oxidation pond 5, neutralization pond 6 and inclined plate sedimentation pond 7 technical processes, therefore the beneficial effect of using the present invention is: can remove urban rubbish More than 70% of the COD (chemical oxygen demand) in the sewage 1 of the transfer station can remove more than 95% of the suspended solids and more than 80% of the grease, which can significantly improve the yellow-brown and brown-black visual properties of the sewage 1 of the waste transfer station. After purification The water 8 is transparent and clear without turbidity, no obvious smell, and good sensory properties. In addition, the present invention can better solve the problems that the high concentration of organic pollution in sewage 1 of garbage transfer station will increase the burden on the sewage plant, the high oil content will affect the normal operation of equipment, and the chroma and odor are difficult to be treated by conventional methods. Insufficient direct takeover combined domestic sewage treatment method, and small footprint, simple structure, convenient operation, the treatment cost per ton is only about 20 yuan.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Referring to the attached figure, a process for biochemical regulation and treatment of municipal solid waste transfer station sewage:

Step 1: The sewage 1 of the municipal waste transfer station first flows into the biochemical regulating tank 2 in the form of a baffle plate, and undergoes anaerobic reaction to realize oil separation, sand settling and reduction of organic load;

The second step: after dissolving the composite flocculant 10 with a ratio of 90% of the total weight of polyaluminum chloride and 10% of polyacrylamide at a dose of 400mg-600mg/L, it passes through the gap between the nozzle of the water injector and the throat. The composite flocculant 10 is inhaled by vacuum suction, and injected into the water regulated by the biochemical adjustment tank 2 at the same time. After mixing, it flows into the coagulation sedimentation tank 3, removes suspended solids and grease, and realizes flocculation and sedimentation to form sludge. The sludge uses gravity The way of sludge discharge is discharged through the sludge valve on the coagulation sedimentation tank 3;

The third step: After the water after removing suspended solids and grease flows into the acidification pool 4, add a concentration of 10% ferrous sulfate 14 solution to the acidification pool 4 by a dose of 0.05-0.08mol/L, and add the composition by weight The acid solution 11 of 10% dilute sulfuric acid or dilute hydrochloric acid ensures that the pH value required for the subsequent chemical oxidation is between 2-4;

The fourth step: the water after the acidification flows into the oxidation pool 5, and the oxidant 12 whose composition is 27.5% hydrogen peroxide by weight is added to the oxidation pool 5 to carry out the oxidation reaction. The molar ratio of hydrogen peroxide and ferrous sulfate 14 is 1-5, and the hydraulic retention time is 2 -4 hours, after the oxidation reaction, ferrous sulfate 14 is oxidized to ferric iron, realizing the oxidation and removal of high-concentration organic pollutants, and eliminating the color and odor of sewage;

Step 5: the water after the oxidation reaction flows into the neutralization tank 6, and the lye 13 whose composition is 10% sodium hydroxide solution by weight is added to carry out the neutralization reaction to adjust the pH value to 7-8;

Step 6: Finally, it flows into the inclined plate sedimentation tank 7 to precipitate unreacted ferrous sulfate 14 and ferric iron to obtain purified water 8 and discharge it into the municipal pipe network 9 .

In the attached drawings: 1 is the sewage of the garbage transfer station; 2 is the biochemical adjustment tank; 3 is the coagulation sedimentation tank; 4 is the acidification tank; 5 is the oxidation tank; 6 is the neutralization tank; 9 is municipal pipe network; 10 is composite flocculant; 11 is acid solution; 12 is oxidant; 13 is lye; 14 is ferrous sulfate.

Embodiment one:

Step 1: The sewage 1 of the municipal waste transfer station first flows into the biochemical regulating tank 2 in the form of a baffle plate, and undergoes anaerobic reaction to realize oil separation, sand settling and reduction of organic load;

The second step: After dissolving the composite flocculant 10 with a ratio of 90% of the total weight of polyaluminum chloride and 10% of polyacrylamide at a dose of 400mg/L, the vacuum pumped between the nozzle of the water jet and the throat The composite flocculant 10 is inhaled by suction, and injected into the water regulated by the biochemical adjustment tank 2 at the same time. After mixing, it flows into the coagulation sedimentation tank 3 to remove suspended solids and grease, and realize flocculation and sedimentation to form sludge. The sludge is discharged by gravity way, discharged through the sludge valve on the coagulation sedimentation tank 3;

The third step: after the water after removing suspended solids and grease flows into the acidification pool 4, add a concentration of 10% ferrous sulfate 14 solution to the acidification pool 4 by a dose of 0.05mol/L, and add the composition with a weight ratio of 10 % acid solution 11 of dilute sulfuric acid or dilute hydrochloric acid to ensure that the required pH value for subsequent chemical oxidation is between 2-4;

The fourth step: the acidified water flows into the oxidation pool 5, and the oxidation pool 5 is fed with an oxidizing agent 12 with a weight ratio of 27.5% hydrogen peroxide to carry out the oxidation reaction. The molar ratio of hydrogen peroxide and ferrous sulfate is 1, and the hydraulic retention time is 2-4. Hours, after the oxidation reaction, ferrous sulfate 14 is oxidized to ferric iron, realizing the oxidation and removal of high-concentration organic pollutants, and eliminating the color and odor of sewage;

Step 5: the water after the oxidation reaction flows into the neutralization tank 6, and the lye 13 whose composition is 10% sodium hydroxide solution by weight is added to carry out the neutralization reaction to adjust the pH value to 7-8;

Step 6: Finally, it flows into the inclined plate sedimentation tank 7 to precipitate unreacted ferrous sulfate 14 and ferric iron to obtain purified water 8 and discharge it into the municipal pipe network 9 .

Embodiment two:

Step 1: The sewage 1 of the municipal waste transfer station first flows into the biochemical regulating tank 2 in the form of a baffle plate, and undergoes anaerobic reaction to realize oil separation, sand settling and reduction of organic load;

The second step: after dissolving the composite flocculant 10 with a ratio of 90% of the total weight of polyaluminum chloride and 10% of polyacrylamide at a dose of 500mg/L, the vacuum pumped between the nozzle of the water injector and the throat The composite flocculant 10 is inhaled by suction, and injected into the water regulated by the biochemical adjustment tank 2 at the same time. After mixing, it flows into the coagulation sedimentation tank 3 to remove suspended solids and grease, and realize flocculation and sedimentation to form sludge. The sludge is discharged by gravity way, discharged through the sludge valve on the coagulation sedimentation tank 3;

The third step: after the water after removing suspended solids and grease flows into the acidification pool 4, add a concentration of 10% ferrous sulfate 14 solution to the acidification pool 4 by a dose of 0.065mol/L, and add the composition with a weight ratio of 10 % acid solution 11 of dilute sulfuric acid or dilute hydrochloric acid to ensure that the required pH value for subsequent chemical oxidation is between 2-4;

The fourth step: the acidified water flows into the oxidation pool 5, and the oxidant 12 whose composition is 27.5% hydrogen peroxide by weight is added to the oxidation pool 5 to carry out the oxidation reaction. The molar ratio of hydrogen peroxide and ferrous sulfate 14 is 3, and the hydraulic retention time is 2-4. Hours, after the oxidation reaction, ferrous sulfate 14 is oxidized to ferric iron, realizing the oxidation and removal of high-concentration organic pollutants, and eliminating the color and odor of sewage;

Step 5: the water after the oxidation reaction flows into the neutralization tank 6, and the lye 13 whose composition is 10% sodium hydroxide solution by weight is added to carry out the neutralization reaction to adjust the pH value to 7-8;

Step 6: Finally, it flows into the inclined plate sedimentation tank 7 to precipitate unreacted ferrous sulfate 14 and ferric iron to obtain purified water 8 and discharge it into the municipal pipe network 9 .

Embodiment three:

Step 1: The sewage 1 of the municipal waste transfer station first flows into the biochemical regulating tank 2 in the form of a baffle plate, and undergoes anaerobic reaction to realize oil separation, sand settling and reduction of organic load;

The second step: After dissolving the composite flocculant 10 with a ratio of 90% of the total weight of polyaluminum chloride and 10% of polyacrylamide at a dose of 600mg/L, the vacuum pumped between the nozzle of the water injector and the throat The composite flocculant 10 is inhaled by suction, and injected into the water regulated by the biochemical adjustment tank 2 at the same time. After mixing, it flows into the coagulation sedimentation tank 3 to remove suspended solids and grease, and realize flocculation and sedimentation to form sludge. The sludge is discharged by gravity way, discharged through the sludge valve on the coagulation sedimentation tank 3;

The third step: after the water after removing suspended solids and grease flows into the acidification tank 4, add a concentration of 10% ferrous sulfate 14 solution to the acidification tank 4 by a dose of 0.08mol/L, and add the composition with a weight ratio of 10 % acid solution 11 of dilute sulfuric acid or dilute hydrochloric acid to ensure that the required pH value for subsequent chemical oxidation is between 2-4;

The fourth step: the water after the acidification flows into the oxidation pool 5, and the oxidant 12 whose composition is 27.5% hydrogen peroxide by weight is added to the oxidation pool 5 to carry out oxidation reaction, the molar ratio of hydrogen peroxide and ferrous sulfate 14 is 5, and the hydraulic retention time is 2-4 Hours, after the oxidation reaction, ferrous sulfate 14 is oxidized to ferric iron, realizing the oxidation and removal of high-concentration organic pollutants, and eliminating the color and odor of sewage;

Step 5: the water after the oxidation reaction flows into the neutralization tank 6, and the lye 13 whose composition is 10% sodium hydroxide solution by weight is added to carry out the neutralization reaction to adjust the pH value to 7-8;

Step 6: Finally, it flows into the inclined plate sedimentation tank 7 to precipitate unreacted ferrous sulfate 14 and ferric iron to obtain purified water 8 and discharge it into the municipal pipe network 9 .

Claims (10)

1. a biochemical regulation and treatment process for sewage of urban domestic garbage transfer station is characterized in that, comprises following technical process:

The first step: city garbage station sewage (1) at first flows into biochemical equalizing tank (2), carries out anaerobic reaction, realizes oil removal, sand setting and reduction organic loading;

Second step: after composite flocculation agent (10) dissolving, by the vacuum take-off effect between water sprayer nozzle and the trunnion composite flocculation agent (10) is sucked, inject the water after biochemical equalizing tank (2) is regulated simultaneously, mix the back and flow into coagulative precipitation tank (3), remove suspended substance and grease, realize that flocculation sediment forms mud, mud uses the mode of gravity spoil disposal, discharges by the sludge valve on the coagulative precipitation tank (3);

The 3rd step: the water behind removal suspended substance and the grease adds ferrous sulfate (14) solution to acidification pool (4), and adds acid solution (11) after flowing into acidification pool (4), guarantees that the desired pH value of subsequent chemistry oxygenizement is between 2-4;

The 4th step: the water after the acidifying flows into oxidation pond (5), add oxygenant (12) to oxidation pond (5) and carry out oxidizing reaction, ferrous sulfate after the oxidizing reaction (14) is oxidized to ferric iron, realizes the oxidation removal of high concentration organic contaminant, cancellation sewage colourity and stench;

The 5th step: water after oxidizing reaction flows into neutralization tank (6), and adding alkali lye (13), to carry out neutralization reaction be 7-8 to regulate the pH value;

The 6th step: flow into inclined-plate clarifying basin (7) at last, make unreacted completely ferrous sulfate (14) and ferric iron precipitate, the water after being purified (8) is gone into municipal pipe network (9) side by side.

2. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: biochemical equalizing tank (2) adopts the traverse baffle form.

3. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: composite flocculation agent (10) is formed by the polyacrylamide proportioning of the polymerize aluminum chloride that accounts for gross weight 90% and 10%.

4. according to claim 1 or 3 described a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station, it is characterized in that: composite flocculation agent (10) 400mg-600mg/L dissolving according to dosage water back and after biochemical equalizing tank (2) is regulated mixes.

5. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: adding concentration by the dosage of 0.05-0.08mol/L is 10% ferrous sulfate (14) solution.

6. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: the composition of acid solution (11) is weight ratio 10% dilute sulphuric acid or dilute hydrochloric acid.

7. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: the composition of oxygenant (12) is weight ratio 27.5% hydrogen peroxide.

8. according to claim 1 or 7 described a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station, it is characterized in that: hydrogen peroxide and ferrous sulfate (14) molar ratio is 1-5.

9. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: the hydraulic detention time 2-4 in the oxidation pond (5) hour.

10. a kind of biochemical regulation and treatment process for sewage of urban domestic garbage transfer station according to claim 1 is characterized in that: the composition of alkali lye (13) is weight ratio 10% sodium hydroxide solution.

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