CN101311131A - Sewage handling method and uses thereof - Google Patents

Abstract

The invention relates to urban community sewage treatment and middle water reuse technology, in particular to a domestic sewage treatment method and its application. Specifically, the domestic sewage enters the sump through the grid, and the domestic sewage from which large solid particles have been removed is pumped through the pump and filtered to the pretreated micro-aerobic aeration filter to degrade the organic pollution in the sewage. The degraded water flows through the outlet of the micro-oxygen aeration filter to the ozone oxidation sterilizer for ozone oxidation, and the oxidized water flows through the outlet of the ozone oxidation sterilizer to the storage pool; the treated regenerated water is used as water for flushing the urinal , directly discharged into the municipal sewage pipe network after flushing the toilet. The invention greatly reduces the treatment cost, and its process operation is simple, practical, convenient to operate, high in treatment efficiency, excellent in regenerated water quality, and high in reuse rate. The process of the invention can reduce community sewage discharge by 50%, and realize the recycling of reclaimed water Reduce water consumption by 30-40%.

Description

A kind of domestic sewage treatment method and its application

technical field

The invention relates to urban community sewage treatment and reclaimed water technology, in particular to a domestic sewage treatment method and its application.

Background technique

At present, the per capita domestic water consumption of urban residents in my country is about 150L/d, of which the water consumption for flushing toilets accounts for a large proportion. Generally, the single flushing volume is 6-8L. Based on 8 times a day, the daily toilet water consumption is about 150L/d. 40% of water usage. Using recycled water instead of pure water for toilet flushing can reduce urban water consumption by 40%.

In the 1990s, the underground infiltration system integrating community domestic sewage treatment and reuse played an important role in the reuse of reclaimed water, but this technology is only suitable for communities with low density of residents and large green areas between buildings. big condition. With the popularization of high-rise residential buildings in cities, the load rate of residents per unit area has doubled, and the per capita green area has dropped significantly. It has become more difficult to adopt underground infiltration treatment processes that occupy a large area.

The existing community sewage treatment and reclaimed water reuse process generally adopts the method of collecting, treating and reusing all the sewage. The reclaimed water enters the next cycle after being used to flush the toilet, so that the biodegradability of the sewage changes with time. Bad, increased processing difficulty and cost. At the same time, with the improvement of residents' living standards, the per capita water consumption gradually increases, and the COD concentration of sewage shows a downward trend, which has a negative impact on economic and technical indicators.

Based on the above considerations, fundamentally changing the existing community sewage treatment and reuse process on site, and researching community sewage treatment and reuse technology based on new concepts will have good application prospects and huge social, economic and social benefits. environmental benefits.

Generally, household water can be divided into four types: kitchen cooking water, daily toilet water, laundry water, bath water, and toilet flushing water. Among them, the water consumption for toilet flushing accounts for 40% of the total water consumption, but its pollution load accounts for 80% of the total pollution load. If the first three kinds of sewage are collected and treated separately, not only the difficulty of treatment will be greatly reduced, but the reclaimed water produced after treatment can basically meet the needs of toilet flushing.

According to the development trend of urban community buildings in my country and the actual situation of water treatment and reuse in the community, on the basis of long-term research, a new technology for the combination of sewage treatment and reuse in the community is proposed.

Contents of the invention

The object of the present invention is to provide an economical, practical, efficient, environmentally friendly and widely applicable domestic sewage treatment process and its application.

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

Treatment method: the domestic sewage enters the sump 2 through the grid 1, and the domestic sewage from which larger solid particles have been removed passes through the pump 3 and passes through the filter 4 to pump the domestic sewage into the pretreated micro-aerobic aeration filter 5 for degradation For organic pollution in sewage, the degraded water flows automatically through the outlet of the micro-oxygen aeration filter 5 to the ozone oxidation sterilizer 7 for ozone oxidation, and the oxidized water is stored in the storage pool 10 through the outlet of the ozone oxidation sterilizer 7 ;

Among them, the pretreatment of the micro-aerobic aeration filter 5: the filter material accounting for 2/3 of the volume of the pool is put into the micro-aerobic aeration filter 5, and the degradation bacteria are inoculated at the same time, and the inoculation amount is calculated according to the percentage of the domestic sewage volume to be treated It is 2%-5%, and oxygen is passed through, and the flow rate of oxygen is 0.010m ³ /min-0.012m ³ /min, so that a layer of biofilm is formed.

The degrading bacteria species are Bacillus sp., Alcaligenes sp. and Zoogloea sp., and the volume-to-number ratio is 1:1:1; wherein: the filter material It is activated coke and vermiculite in a weight ratio of 1:1.

When the micro-aerobic aeration filter 5 forms a biofilm, the filter material and the degradation bacteria are cultivated in domestic sewage at room temperature, and the water used for cultivating the filter material and the degradation bacteria is changed every 4-6 days, and the amount of water changed each time Accounting for 50%-60% of the total water used for cultivating filter materials and degrading strains, a layer of biofilm is formed after culturing for 25-40 days.

The hydraulic retention time is 4-6h. The backwash cycle is 20 days; the ozone concentration in the ozone oxidation sterilizer 7 is 40-100mg/L.

Application of treatment methods: urban residential quarters, hotels, schools; at the same time, the treated sewage is used for flushing urinals.

L^-1，符合中水指标要求。The principle of the present invention: the use of micro-oxygen aeration filter is to dissolve the oxygen produced by the air compressor into the mixed sewage in a forced way. In addition to supplying oxygen, the aeration also plays a stirring role to ensure and adsorb on the surface of the filter material. Fully contact with microorganisms on the surface, and quickly degrade. In the upflow biological filter, both oxygen and sewage enter from the bottom of the filter, the purpose of which is to facilitate the full contact between the pollutants in the sewage and the microorganisms, and ensure the treatment effect. At the same time, the organic pollutants that are difficult to degrade in domestic sewage come from the surfactant in washing water and the oil in cooking water. The micro-oxygen aeration filter of the present invention is inoculated with cultured and domesticated detergent and animal and vegetable oil high-efficiency degradation bacterial agents, and a layer of biofilm is formed on the surface of the filter material. Biofilm has the ability to degrade organic pollutants, and the success of biofilm formation is related to the removal effect of pollutants. And in order to ensure that the regenerated water treated by the micro-oxygen aeration filter meets the standard of reclaimed water, ozone disinfection is used for advanced treatment to further reduce the COD load and kill pathogenic bacteria in the water. The ozone concentration is controlled in the range of 40-100mg/L, which can ensure that the total number of coliform bacteria in the effluent water is less than 3

L ^-1 , in line with the requirements of reclaimed water indicators.

Compared with prior art, the present invention has following advantage:

1. The process of the present invention is simple, feasible, practical, easy to operate, high in treatment efficiency, excellent in regenerated water quality, and high in reuse rate. The semi-open cycle of the present invention can effectively avoid the problem of poor biodegradability of sewage and achieve long-term stability of the system In operation, the process of the invention can reduce community sewage discharge by 50%, realize reclaimed water recycling and reduce water consumption by 30-40%.

2. The micro-aerobic aeration filter of the present invention has a membrane with degradation activity for organic pollutants, which can ensure the removal effect of pollutant detergents and grease pollutants in domestic sewage.

3. The treatment of pollutants is relatively thorough. The present invention utilizes multi-stage treatment such as an upflow micro-oxygen filtration system, filter, and ozone oxidation sterilizer technology, so that the treatment efficiency is high and the regenerated water quality is excellent.

3. The present invention can design different scales according to the specific conditions of urban residential areas, hotels and schools, etc., such as 300 equivalents, and can design a water collection tank, a micro-oxygen aeration filter tank and a storage tank with a volume of 15m ³ , which is simple in structure, low in cost, and adaptable. wide range.

4. Using the present invention to reuse urban domestic sewage, such as collected kitchen cooking water, daily washing water, laundry water and bathing water, on the one hand reduces the consumption of fresh tap water, and also reduces the amount of sewage discharge. It has good economic benefits and broad application prospects for urban residential quarters, hotels, schools, restaurants, etc.

Description of drawings

Fig. 1 is the flow chart of the present invention for urban community domestic sewage treatment and reuse process.

Fig. 2 is a flow chart of the domestic sewage treatment process of the present invention.

1. Grille, 2. Pool, 3. Suction pump, 4. Filter, 5. Micro-oxygen aeration filter, 6. Air compressor, 7. Ozone oxidation sterilizer, 8. Ozone generator, 9. Oxygen cylinders, 10. Storage pools

Detailed ways

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

Example 1

Pretreatment of the micro-oxygen aeration filter 5: put filter material activated coke and vermiculite accounting for 2/3 of its volume in the micro-oxygen aeration filter 5, and then add domestic sewage to make the filter material and degradation bacteria in the micro-oxygen aeration filter 5 Its environment, and grows under the room temperature condition, when it inoculates the degrading strain, by volume percentage, the inoculum amount of the degrading strain is: 2.5% of the domestic sewage volume added when the filter material and the degrading strain grow, and intermittently Oxygen flow, oxygen flow rate 0.012m ³ /min, operating at a room temperature of 20°C-28°C, changing the water used for cultivating filter materials and degrading bacteria every 5 days, the amount of water exchanged accounted for the cultivation of filter materials and degrading bacteria 50% of the total amount of water is used, and a layer of biofilm is formed after 35 days of operation: wherein: the weight ratio between activated coke and vermiculite is 1: 1, and the water level in the micro-aerobic aeration filter tank 5 is higher than the filter material ; The degrading strains are Bacillus sp., Alcaligenes sp. and Zoogloeasp., and the volume-to-number ratio is 1:1:1; wherein: the filter material It is activated coke and vermiculite in a weight ratio of 1:1.

Take 2L each of kitchen cooking sewage, washing sewage, laundry sewage and bathing sewage, totaling 8L, pass through the stainless steel grid 1 with a gap of 2mm, remove larger solid particles, and enter the sump 2. At this time, the sewage in the sump 2 The comprehensive index of sewage water quality CODcr is 52mg/L, BOD ₅ is 29mg/L, pH is 7.6, SS is 18mg/L (see Table 1). The organic pollution in the sewage is degraded in the micro-oxygen aeration filter 5, and oxygenated into the micro-oxygen aeration filter 5 through the air compressor 6, and the degraded water flows through the water outlet of the micro-oxygen aeration filter 5 to the The ozone oxidation sterilizer 7 carries out ozonation, and the oxygen in the oxygen bottle 9 generates ozone through the ozone generator 8, and the gas enters the ozone oxidation sterilizer 7 through a flow meter to oxidize and sterilize the degraded water therein, and adjust the ozone concentration to be 40- 100mg/L, the reaction time is 20min. The oxidized water is automatically stored in the storage pool 10 through the outlet of the ozone oxidation sterilizer 7. The storage tank 10 is designed with a water volume regulator. When the treated water level reaches the design water level, the storage tank 10 stops receiving. When the water level is insufficient, tap water is automatically replenished. .

Among them, the filter material is quartz sand; the strains are cultivated and domesticated degrading surfactants and the dominant degrading bacteria of animal and vegetable oils; the water pumping capacity of the sewage pump is 6m ³ /h. The micro-aerobic aeration filter adopts the upflow type for water extraction and oxygenation. The oxygen flow rate of the air compressor 6 for oxygenation is 0.018m ³ /min, the hydraulic retention time is 5.5h, and the backwash cycle is 20d.

Detect the water quality of the storage tank 10: CODcr 4.6mg/L, BOD ₅ 1.6mg/L, total E. coli 2/L, fecal E. coli not detected, SS 2.1mg/L, pH7 (see Table 1). Moreover, the quality index of the treated reclaimed water complies with the water quality standard for urban domestic miscellaneous water (GB-T18920-2002), and can be used as water for flushing toilets, and the water can be directly discharged into the urban pipe network after flushing the toilets.

Table 1

*Water quality standard for urban miscellaneous water (GB-T18920-2002).

Claims (6)

1. domestic sewage processing method, it is characterized in that: sanitary sewage enters water collecting basin (2) through grid (1), make sanitary sewage be extracted into the organic contamination in the degradation of sewage in pretreated little oxygen aerating filter (5) by lift pump (3) and through filter (4) sanitary sewage of removing big solid particulate, water after the degraded flows automatically to ozone oxidation sterilizing device (7) through the water outlet of little oxygen aerating filter (5) and carries out ozone oxidation, and the water after the oxidation is stored in storage pool (10) through the gravity flow of ozone oxidation sterilizing device (7) water outlet;

Wherein, the pre-treatment of little oxygen aerating filter (5): throw in the filtrate that accounts for this pool volume 2/3 in little oxygen aerating filter (5), the bacterial classification of inoculation degraded simultaneously, inoculum size is counted 2%-5% according to the per-cent of pending sanitary sewage volume, and aerating oxygen, oxygen gas flow rate 0.010m ³/ min-0.012m ³/ min makes it form one deck microbial film.

2. by the described domestic sewage processing method of claim 1, it is characterized in that: described degraded bacterial classification is genus bacillus, Alcaligenes and moving glue bacillus, and its volume parts ratio is 1: 1: 1; Wherein: described filtrate is activated carbon char and vermiculite, and it is 1: 1 by weight.

3. by the described domestic sewage treatment process of claim 1, it is characterized in that: when little oxygen aerating filter (5) forms microbial film, filtrate and degraded bacterial classification are in sanitary sewage, cultivate under the room temperature, changed the water of once cultivating filtrate and degraded bacterial classification every 4-6 days, each quantity of exchanged water accounts for the 50%-60% that cultivates filtrate and the used water Total Water of degraded bacterial classification, cultivates 25-40 days, promptly forms one deck microbial film.

4. by the described domestic sewage processing method of claim 1, it is characterized in that: hydraulic detention time 4-6h.Backwashing period 20 days.

5. by the described domestic sewage processing method of claim 1, it is characterized in that: the ozone concn in the ozone oxidation sterilizing device (7) is 40-100mg/L.

6. the application of the described domestic sewage processing method of claim 1 is characterized in that: city resident sub-district, hotel, school; Sewage after handling simultaneously is used for flushing toilet bowl.

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