HJ 574-2010Technical specifications of domestic pollution control for town and village (English PDF)

5.1 Source control technology

5.1.1 The source of rural domestic sewage can be controlled by the technical route of Figure 1.

Grey water artificial wetland, land treatment and other technical reuse Blackwater domestic sewage agricultural compost, three septic tanks, purified biogas tanks, etc.

Figure 1 source control technology route

5.1.2 It is advisable to use non-water flushing sanitary wares, such as manure and urine collection toilets and double hopper funnel toilets. The construction of the toilet can refer to GB 19379.

Or directly use equipment products.

5.1.3 The use of fecal and urine-differentiated sanitary latrines shall meet the following requirements.

(1) It is recommended to use organic matter with humidity 1.5 m). Land treatment technologies include slow percolation, rapid percolation, and surface flow.

(1) Main design parameters.

a) The annual hydraulic load of the slow percolation system is 0.5-5 m/a, the shallowest depth of groundwater is greater than 1.0 m, and the soil permeability coefficient is preferably 0.036~ 0.36 m/d;

b) The annual hydraulic load of the rapid infiltration system is 5 to 120 m/a, and the ratio of the flooding period to the drying period should be less than 1;

c) The annual hydraulic load of the surface flow system is 3-20 m/a.

(2) When designing the land, the soil particle composition and soil organic matter content should be adjusted according to the soil conditions of the application site.

(3) Land treatment systems shall not be used in concentrated water supply protection belts, aquifer outcrops, fractured rock formations and lava areas.

5.3.3 Stabilization pond

The Stabilization Pond is suitable for use in rural areas where lakes, ponds, depressions and unused water surfaces are available. It is advisable to choose the type to handle the pond regularly.

Oxygen ponds, facultative ponds, aerobic ponds, etc. The aeration pond should be used in places where the land area is limited.

(1) Stabilization ponds shall take necessary anti-seepage treatment and shall be provided with sanitary protection belts between residential areas.

Main design parameters of different types of stable ponds.

a) anaerobic pond surface load (BOD5) 15 ~ 100 g/(m2 · d);

b) facultative pond surface load (BOD5) 3 ~ 10 g/(m2 · d);

c) aerobic pond surface load (BOD5) 2 ~ 12 g/(m2 · d), the total residence time can be 20 ~ 120 d;

d) Aeration pond surface load (BOD5) 3 ~ 30 g/(m2 · d).

Areas with high annual average temperature use high BOD5 surface load, and areas with low annual average temperature use low BOD5 surface load.

(2) The sludge accumulation volume of the stabilized pond sludge is 40-100 L/(a·person), which should be operated in parallel and rotated to remove sludge. Stable pond the site should be selected downstream of the drinking water source; the sludge in the pond should be properly treated, and the sludge dewatering should be dried naturally by sludge drying bed; sludge as farmland fertilizer when using materials, it should comply with the relevant provisions of GB 4284.

5.3.4 Purification of biogas digesters

The domestic sewage purification biogas digesters can be used for the following occasions. public toilets in rural concentrated residential areas; no sewage collection or unreasonable pipe network Rural, folk custom villages, etc.

(1) The use of purified biogas digesters should ensure that the winter water temperature is maintained at 6 to 9 ° C, which can be combined with greenhouse construction to assist in heating.

The effective pool capacity is calculated as follows.

Na q tv × ×= × (1)

Where. nu1--effective pool capacity, m3;

N--serving population;

a--Sanitary equipment installation rate, residential area, hotel, collective dormitory to take 1, office building, teaching building to take 0.6;

Q--the amount of sewage per capita, L/d;

t--Sewage retention period, d, residence time is 2 to 3 days.

(2) The functional area for purifying the biogas tank should include. a pretreatment area, a pretreatment area, and a post treatment area. The pretreatment area shall be provided with a grille and grit chamber.

It is advisable to use a grid gap of 1 to 3 cm. The pretreatment zone is an anaerobic tank, and the pretreatment zone for mixed sewage collection is a first-stage anaerobic digestion, and the manure is separately collected.

The pre-treatment zone of the collection is secondary digestion. The effective pool capacity of the anaerobic pool in the pretreatment area should account for 50% to 70% of the total effective pool capacity. The pretreatment area should be placed soft for semi- or semi-soft fillers, the volume of the filler should be 15% to 25% of the total pool volume. The upper treatment zone uses an upflow filter, each pool needs to be atmospheric in the same way, a polyurethane foam board is placed between the sections as a filter layer. Polyurethane filter foam board should be replaced every 4 to 5 years and should be replaced every 10 years.

Soft filler.

(3) The sludge in the purified biogas tank increases with the prolongation of the fermentation time, and needs to be cleaned once in 1 to 2 years. The biogas produced in the purification pond should be collected use. Biogas utilization should be carried out in strict accordance with the provisions of GB 9958.

5.3.5 Small sewage treatment plant

The small-scale sewage treatment device is suitable for several households or dozens of households in developed rural areas, relatively concentrated, newly built residential areas and no centralized collection pipelines.

And the situation of centralized sewage treatment plants.

The small sewage treatment device, also known as the purification tank or the buried treatment device, is divided into an anaerobic and aerobic treatment device.

a) Anaerobic biological treatment equipment (or unpowered buried sewage treatment facilities) may be specified in 5.3.4.

b) Aerobic biological treatment equipment (or powered buried sewage treatment facilities). Hydraulic retention time with pre-treatment of the primary settling tank (HRT) is generally 1.5 h, aerobic treatment should use contact oxidation, SBR and other processes, process parameters should be in accordance with the provisions of 5.4 of this standard set.

Small sewage treatment equipment is available in reinforced concrete structures, glass reinforced plastics and steel structures. Steel structure reactor needs to be preserved Work, its service life should be guaranteed for more than 15 years.

5.4 Centralized sewage treatment technology

5.4.1 Developed rural areas, considering the construction of centralized sewage treatment facilities according to the amount of water, the process can be activated sludge method, oxidation ditch method, Biofilm method, etc. In rural areas where centralized processing technology is the main process, the corresponding pretreatment process should be combined according to the requirements of different processing technologies.

And post-treatment process.

5.4.2 Using centralized processing technology, investment and operating expenses can be reduced by the following methods while ensuring the processing effect.

(1) The preparation of floor space, greening rate, auxiliary facilities and staffing may be lower than the relevant standards in the design manual;

(2) Priority is given to the use of terrain when site selection, reducing power boost;

(3) Adopt simple and easy automatic operation or hand and automatic linkage operation mode;

(4) Water treatment structures can be replaced by non-concrete buildings, such as earth embankments, bricks, etc., as well as simple anti-seepage abandoned pits.

5.4.3 Traditional activated sludge method.

(1) The sludge load (BOD5/MLSS) of the traditional activated sludge process should adopt medium and high load. 0.15~0.3 kg/(kg·d);

(2) When increasing the nitrogen removal requirement, the aerobic/aerobic (A/O) biological treatment process is adopted, and the hydraulic retention time (HRT) of the anoxic section is generally Controlled at 0.5 ~ 2 h, sludge load (BOD5/MLSS) should be 0.1 ~ 0.15 kg/(kg · d);

(3) When increasing phosphorus removal requirements, the anaerobic section HRT is generally controlled at 1 to 2 h, and the sludge load (BOD5/MLSS) is 0.1 to 0.25 kg/(kg·d);

(4) Simultaneous nitrogen and phosphorus removal using anaerobic/anoxic/aerobic method (A2/O), HRT is generally controlled in the anaerobic section for 1 to 2 h, and the anoxic section is 0.5 to 2 h, the sludge load (BOD5/MLSS) should be 0.1 to 0.2 kg/(kg·d).

5.4.4 Oxidation ditch. There may be no primary sedimentation tank before the oxidation ditch system, generally by the ditch body, aeration equipment, influent distribution well, effluent overflow weir and guide the flow device is composed of parts. The main design parameters of the oxidation ditch are shown in Table 1.

Table 1 Main design parameters of delayed aeration oxidation ditch

Project unit value

Sludge load (BOD5/MLSS) kg/(kg·d) 0.05~0.10 Sludge concentration g/L 2.5~5 Sludge age d 15~30 Sludge reflux ratio% 75~150 Total processing efficiency % > 95 (1) The oxidation ditch is generally formed as an annular ditch type, and its plane may be a combination of a circular shape and an elliptical shape or a rectangular shape. Its surrounding pool wall can be rooted According to the soil condition, it is dug into a slope and lining, and it can also be a reinforced concrete straight wall. The treatment structure should be protected against local temperature and environmental conditions.

Freezing measures.

(2) The width of the oxidation ditch, the effective water depth depends on the land occupation, the grouping of the oxidation ditch, and the performance of the aeration equipment. In general, when when using aeration brush, the effective water depth is 2.6 ~ 3.5 m; when using aeration disc, the effective water depth is 3.0 ~ 4.5 m; when using surface exposure when the machine is used, the effective water depth is 4.0 to 5.0 m.

(3) Horizontal baffles and baffles shall be provided on the upstream and downstream of all aerators in the oxidation ditch to ensure horizontal and vertical mixing.

Hehe. A diversion wall shall be provided at the corner, and the diversion wall shall be located inside the deflecting curve. The number of diversion walls can be determined according to the width of the trench, only A diversion wall can be set at 1/3 of the inner wall (the outer channel is half the width of the pool when the diversion wall is two). The diversion wall should be higher than the water level 0.2~ 0.3 m.

(4) The flow velocity in the oxidation ditch shall not be less than 0.25 m/s.

(5) When nitrogen and phosphorus removal are used, an anaerobic zone and an anoxic zone shall be provided in the oxidation ditch. The design between the zones shall comply with the provisions of 5.4.3.

5.4.5 Biological contact oxidation method.

(1) The contact oxidation reaction tank is generally a rectangular pool body, which should include a structural layer, a packing layer, a stable water layer and an ultra-high composition from bottom to top, and the filler the height of the layer should be 2.5-3.5 m, the effective water depth should be 3-5 m, and the ultra-high should not be less than 0.5 m. The reaction cell should generally not be less than two, each the pool is divided into two rooms.

(2) The water in the biological contact oxidation pond should be prevented from short-flow, and the effluent should be sputum-type effluent. The enthalpy of the catchment should be 2.0-3.0 L/(s·m).

Drainage and venting facilities should be provided at the bottom of the pool.

(3) The BOD5 volumetric load in contact with the oxidation tank should be 0.5-1.0 kg/(m3·d) for biological carbon removal and 0.2-° for nitrification.

0.5 kg/(m3 · d). When the reaction tank is aerated in the whole pool, the aeration intensity should be 10-20 m3/(m2·h), and the gas-water ratio should be controlled to 8.1.

(4) The amount of sludge produced by the biological contact oxidation system can be calculated as the amount of dry sludge produced by 0.35 to 0.4 kg per kilogram of BOD5.

5.4.6 Natural desic...