CN103819056B - The recycling system that a kind of sewage is irrigated safely - Google Patents

Abstract

The invention discloses a resource utilization system for safe irrigation of sewage, which includes an anaerobic pool, a short-range aerobic biological filter, and a connecting pipe. The anaerobic pool is sequentially divided into a water inlet area, a combined packing area and a precipitation area. The short-range aerobic biological filter is provided with a filling area, a supporting area and a water outlet area in sequence, wherein the sedimentation area of the anaerobic tank is connected with the filling area of the aerobic biological filter through a connecting pipe. The recycling system for safe irrigation of domestic sewage of the present invention aims at retaining the amount of nitrogen and phosphorus in sewage and realizing inorganicization, improves the value of resource utilization of sewage, and at the same time realizes the concentration of organic matter in the effluent under low energy consumption conditions Reduced to below 50mg/L, which improves the safety of sewage irrigation and avoids the problems of crop root rot and land compaction that are easily caused by traditional sewage irrigation. In addition, according to the feature that ammonia nitrogen is beneficial to the direct absorption and utilization of crops, the system of the present invention shortens the process of the aerobic biological filter and realizes energy saving and consumption reduction.

Description

A recycling system for safe irrigation of sewage

technical field

The invention relates to a sewage resource utilization system for rural domestic sewage for safe irrigation, and belongs to the technical field of water treatment and sewage resource utilization.

Background technique

At present, the concept of resource utilization of domestic rural domestic sewage is weak, and most of the treatment technologies are aimed at removing various pollutants in sewage, without considering how to retain nutrients such as nitrogen and phosphorus in sewage. In the traditional A/O treatment system for the purpose of carbon removal, nitrogen removal and phosphorus removal, the residence time of the anaerobic tank is 14h, the volume load of the aerobic biological filter is 0.50kgCOD /(m3 d) and the hydraulic load is 4.0 m3/ ( m2·d), the effluent meets the national "Urban Sewage Treatment Plant Pollutant Discharge Standard" (GB18918-2002) Grade A standard, the concentration of ammonia nitrogen should be less than 5mg/L, the concentration of phosphate should be less than 0.5mg/L, and the concentration of COD should be less than 50mg/L. At present, many foreign water treatment experts are actively advocating the sewage treatment concept of "in situ treatment and in situ reuse, realizing water balance and water cycle". The transformation of rural domestic sewage from treatment to resource utilization is not only an inevitable trend in the development of water treatment technology in the future, but also an effective way to solve the existing problems in the current rural domestic sewage treatment. Compared with the rural sewage treatment technology that has received extensive attention and mature technology, the resource utilization technology of rural domestic sewage needs more attention. Nitrogen and phosphorus contained in domestic sewage are pollutants to the water environment, but they are essential nutrients for agricultural production and are a precious resource. Therefore, effective use of them is an important way to realize ecological agriculture. Therefore, it is necessary to develop a recycling system that can realize the utilization of recycled water resources and fully recover nitrogen and phosphorus for safe irrigation of sewage.

Contents of the invention

Purpose of the invention: The technical problem to be solved by the present invention is to provide a recycling system for safe sewage irrigation that can realize the utilization of recycled water resources and the full recovery of nitrogen and phosphorus. The system has a simple and reasonable structure, low construction costs, low operating costs, and is easy to maintain manage.

Summary of the invention: In order to solve the above technical problems, the technical solution adopted in the present invention is:

A resource recovery system for safe sewage irrigation, including anaerobic tank and aerobic biological filter, and also includes connecting pipes, the anaerobic tank is divided into a water inlet area, a combined packing area and a sedimentation area in sequence, and the aerobic biological The filter tank is sequentially provided with a filling area, a supporting area and a water outlet area, wherein the sedimentation area of the anaerobic tank is connected with the filling area of the aerobic biological filter through connecting pipes.

Wherein, the combined packing area accounts for 80% of the volume of the anaerobic tank, and the described packing area accounts for 75% of the volume of the aerobic biological filter.

Wherein, the filler in the combined filler area is a Ф150mm×80mm combined filler, and the filler in the filler area is ceramsite with a particle size of 3-6mm.

Wherein, the connecting pipe is provided with a lifting pump.

Wherein, the top of the settling area is provided with a sealing ring and a cover plate in sequence.

Wherein, a mud discharge pipe is provided in the water inlet area.

Wherein, a ventilation pipe is provided on the side wall of the packing area.

Wherein, a perforated supporting plate is provided between the supporting area and the water outlet area.

Wherein, ventilation holes are provided on the side wall of the water outlet area.

Beneficial effects: Compared with the prior art, the sewage safety irrigation resource utilization system of the present invention still has the required biological treatment effect under the condition of low energy consumption, that is, the inorganic nitrogen and phosphorus and the removal of organic matter; in addition, the present invention The system does not have a return channel, and the dissolved oxygen demand of the aerobic biological filter can be guaranteed under natural ventilation conditions, thereby achieving the effect of saving energy and reducing consumption; finally, the system of the present invention solves the problem of crop root rot and soil pollution caused by sewage irrigation in the past. Problems such as hardening, maximize the retention of the form and quantity of nitrogen and phosphorus that are easy to be used by crops in domestic sewage, and realize the resource utilization of sewage and the full recovery of nitrogen and phosphorus. Therefore, the resource recovery system for safe sewage irrigation of the present invention has a wide range of applications Prospects, compared with the process flow of phosphorus and nitrogen removal in rural sewage commonly used now, the system of the present invention omits the subsequent nitrification reaction and denitrification reaction, shortens the system flow, reduces the demand for dissolved oxygen, does not require additional aeration, and reduces energy consumption. consumption.

Description of drawings

Fig. 1 is the transverse sectional schematic diagram of the recycling system of sewage safety irrigation of the present invention;

Fig. 2 is a schematic longitudinal sectional view of the recycling system for safe irrigation of sewage according to the present invention.

Detailed ways

The present invention will be further described below in combination with specific embodiments and accompanying drawings.

The combined filler used in the system of the present invention is a filler with a specification of Ф150mm×80mm. The central rope of the combined filler is a plastic rope, surrounded by aldehyde fibers or polyester filaments, which are evenly pressed on the double-circle large plastic ring. The length of the combined filler bundle is 0.4 m, the number of filler bundles is 8, and the filler bundles are evenly suspended in the combined filler area; the filler in the filler area is ceramsite with a particle size of 3-6mm.

As shown in Figures 1 to 2, the resource utilization system for safe sewage irrigation of the present invention includes an anaerobic tank 1 and an aerobic biological filter tank 2, and also includes a connecting pipe 3, and the anaerobic tank 1 is divided into water intake areas in turn 4. Combining the packing area 5 and the sedimentation area 6, the aerobic biofilter 2 is provided with the packing area 7, the supporting area 8 and the water outlet area 9 in turn, wherein the sedimentation area 6 of the anaerobic tank 1 and the aerobic biofilter 2 The packing area 7 is connected through the connecting pipe 3. Among them, the packing specification of the combined packing area 5 is Ф150mm×80mm packing, the central rope is a plastic rope, and there are aldehyde fibers or polyester threads around it evenly pressed on the double-circle large plastic ring; the combined packing area 5 occupies 80% of the volume of the anaerobic tank 1. %, the filler area 7 is ceramsite filler, and the filler area 7 accounts for 75% of the volume of the aerobic biofilter 2; In the aerobic biofilter 2, a water distributor 11 can also be provided at the end where the connecting pipe 3 is connected to the packing area 7, and the water distributor 11 turns the sewage in the connecting pipe 3 into fine water droplets and sprays it on the packing area 7 surface layer. The top of the sedimentation area 6 is provided with a sealing ring 12 and a cover plate 13 in sequence, a mud discharge pipe 14 is provided in the water inlet area 4, a ventilation pipe 15 is provided on the side wall of the packing area 7, and the space between the supporting area 8 and the water outlet area 9 A perforated support plate 16 is provided, and ventilation holes 17 are provided on the side wall of the water outlet area 9 .

The sewage enters the anaerobic tank 1 with the combined packing area 5 from the water intake area 4. After hydraulic retention for 3 h -4 h, part of the organic nitrogen and phosphorus in the sewage are inorganicized to reduce the organic load. The sewage then enters the sedimentation area 6 and passes through The connecting pipe 3 enters the filling area 7 of the aerobic biofilter 2, and the sewage in the connecting pipe 3 can be sprayed on the surface of the filling area 7 by the water distributor 11 as fine water droplets. Under natural oxygenation conditions, it can be adjusted by increasing the hydraulic load The biochemical reaction time in the oxygen biofilter 2 keeps the reaction in the carbonization and ammonification stage, converts organic nitrogen into ammonia nitrogen and organic phosphorus into phosphate, and at the same time reduces the concentration of organic matter, and the sewage flows through the packing area 7 after reaction The support area 8 enters the water outlet area 9, and is discharged into the farmland by the water outlet pipe of the water outlet area 9 for irrigation. The pilot test shows that the effluent ammonia nitrogen concentration of the recycling system using the sewage safe irrigation of the present invention is 20-30 mg/L, the phosphate concentration is 4-6 mg/L, and the COD concentration is below 50 mg/L.

When the optimal volume load of the aerobic biofilter 2 is 0.80kgCOD /(m3 d) and the hydraulic load is 5.64 m3/ (m2 d), the sewage treatment effect is the best, that is, the concentration of organic matter in the effluent is reduced to 50mg Below /L, the concentration of ammonia nitrogen is 20-30mg/L, and the concentration of phosphate is 4-6 mg/L.

By controlling the hydraulic load and the height of the packing layer, the present invention controls the biochemical reaction of the aerobic biological filter in the carbonization and ammonification stages, and cancels the denitrification process, realizes the short-range reaction process, and reduces the demand for dissolved oxygen, thereby Reduce energy consumption, reduce the concentration of organic matter in the effluent to the level of safe irrigation, and increase the ammonia nitrogen content that is beneficial to the direct absorption and utilization of crops.

The resource utilization system for safe sewage irrigation of the present invention maximizes the retention of the form and quantity of nitrogen and phosphorus that are easy to be used by crops in rural domestic sewage, and solves the problems of crop root rot and soil compaction caused by direct use of sewage irrigation. The nitrogen and phosphorus in the water can be safely reused for farmland irrigation, and the recycling of nitrogen and phosphorus in rural domestic sewage has been realized.

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the examples, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (8)

1. A recycling system for safe sewage irrigation, characterized in that it includes an anaerobic tank and an aerobic biofilter, and also includes a connecting pipe, and the anaerobic tank is successively divided into a water inlet area, a combined packing area and a sedimentation area , the aerobic biofilter is sequentially provided with a packing area, a supporting area and a water outlet area, wherein the sedimentation area of the anaerobic tank is connected with the packing area of the aerobic biological filter through a connecting pipe, and the packing area of the combined packing It is a Ф150mm×80mm composite filler, the filler in the filler area is ceramsite with a particle size of 3-6mm, the volume load of the aerobic biological filter is 0.80kgCOD/(m ³ ·d), and the hydraulic load is 5.64m ³ / (m ² ·d). 2. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: the combined filling area accounts for 80% of the volume of the anaerobic tank, and the filling area accounts for 75% of the volume of the aerobic biological filter. 3. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: the connecting pipe is provided with a lifting pump. 4. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: a sealing ring and a cover plate are sequentially provided on the top of the settling area. 5. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: a mud discharge pipe is provided in the water inlet area. 6. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: a ventilation pipe is provided on the side wall of the filling area. 7. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: a perforated supporting plate is provided between the supporting area and the water outlet area. 8. The sewage safe irrigation resource utilization system according to claim 1, characterized in that: ventilation holes are provided on the side wall of the water outlet area.