A sewage treatment plant sludge treatment process and system

Abstract

The invention discloses a treatment process of sludge from a wastewater treatment plant, and the treatment process comprises the following steps: firstly carrying out gravity sedimentation on sludge; sequentially carrying out aerobic digestion on the obtained concentrated sludge and sedimentation treatment on the digested sludge; after the digested sludge is settled, obtaining digested sludge anddigestion tail water; discharging the digested sludge; and carrying out aquatic plant purification treatment on the digestion tail water. The invention also discloses a system for realizing the process. After the digestion treatment of the concentrated sludge, the stabilization degree of the sludge is greatly improved; and the digestion tail water enters an aquatic plant purification system, nutrient elements in water are absorbed and utilized by the plants, and the nutrient elements are not transferred to the discharged water from the sludge, so that the sludge reduction and tail water purification are simultaneously achieved.

Description

technical field

[0001] The invention relates to a sludge treatment process and system of a sewage treatment plant, including the system combination of sludge reduction and tail water plant purification. Background technique

[0002] With the popularization of urban sewage treatment facilities in China, the improvement of treatment rate and the deepening of treatment degree, the sludge generation of sewage treatment plants has increased rapidly. According to the data of the Ministry of Housing and Urban-Rural Development, by the end of 2009, 1,992 urban sewage treatment plants had been put into operation nationwide, and the urban sewage treatment capacity reached 28 billion m 3 , the production of wet sludge (80% moisture content) has exceeded 20 million tons, and the annual sludge discharge of urban sewage treatment plants in my country is still growing at a rate of more than 10% per year. The sludge of urban sewage treatment plants is mainly biochemical residual sludge. Th...

Examples

Embodiment 1

[0026] Such as figure 2 The sludge treatment system shown includes a control system 3 and a reaction tank body, and the tank body is made of glass fiber reinforced plastic. The reaction tank body includes sedimentation tank 2, aerobic digestion tank 6, digested sludge sedimentation tank 8 and aquatic plant purification tank 9 connected in sequence; connection; the bottom of the aerobic digestion tank is evenly covered with aeration pipes 7, and the aeration pipes 7 are connected to the blower 5; the bottom of the digested sludge sedimentation tank 8 is provided with a mud discharge pipe 12; The liquid pipe 13 is connected; the control system 3 controls the sludge inlet volume of the sludge pump 4 and the blast volume of the blower 5 .

[0027] A floating frame 11 of plastic material is arranged at the liquid level of the aquatic plant purification tank 9 to maintain the relative plant spacing of the aquatic plants.

[0028] The sludge of the sewage treatment plant first ent...

Embodiment 2

[0033] Using the same system as in Example 1, the difference from Example 1 is that in the aquatic plant purification stage, the residence time of the digested tail water in the purification tank is increased to 20 days, and it is carried out at room temperature (23 ± 2 ° C), aerobic digestion The sludge concentration in the pool is maintained at 12000-15000mg / L, and the dissolved oxygen solubility is controlled at 5.0-6.0mg / L. After aerobic digestion, the sludge organic matter degradation rate (MLVSS degradation rate) is basically the same as that of Example 1, reaching urban Pollutant discharge standard for sewage treatment plants (GB 18918-2002); digested tail water enters the purification tank, and the planting density of aquatic plants (Pteris chinensis) in the tank is maintained at 25 plants / m 2 After 20 days of adsorption and absorption by aquatic plants, the concentration of COD, TN and TP in the effluent can be reduced to 43mg / L, 14mg / L and 0.5mg / L respectively, reachi...

technical field

[0001] The invention relates to a sludge treatment process and system of a sewage treatment plant, including the system combination of sludge reduction and tail water plant purification. Background technique

[0002] With the popularization of urban sewage treatment facilities in China, the improvement of treatment rate and the deepening of treatment degree, the sludge generation of sewage treatment plants has increased rapidly. According to the data of the Ministry of Housing and Urban-Rural Development, by the end of 2009, 1,992 urban sewage treatment plants had been put into operation nationwide, and the urban sewage treatment capacity reached 28 billion m 3 , the production of wet sludge (80% moisture content) has exceeded 20 million tons, and the annual sludge discharge of urban sewage treatment plants in my country is still growing at a rate of more than 10% per year. The sludge of urban sewage treatment plants is mainly biochemical residual sludge. Th...

Examples

Embodiment 1

[0026] Such as figure 2 The sludge treatment system shown includes a control system 3 and a reaction tank body, and the tank body is made of glass fiber reinforced plastic. The reaction tank body includes sedimentation tank 2, aerobic digestion tank 6, digested sludge sedimentation tank 8 and aquatic plant purification tank 9 connected in sequence; connection; the bottom of the aerobic digestion tank is evenly covered with aeration pipes 7, and the aeration pipes 7 are connected to the blower 5; the bottom of the digested sludge sedimentation tank 8 is provided with a mud discharge pipe 12; The liquid pipe 13 is connected; the control system 3 controls the sludge inlet volume of the sludge pump 4 and the blast volume of the blower 5 .

[0027] A floating frame 11 of plastic material is arranged at the liquid level of the aquatic plant purification tank 9 to maintain the relative plant spacing of the aquatic plants.

[0028] The sludge of the sewage treatment plant first ent...

Embodiment 2

[0033] Using the same system as in Example 1, the difference from Example 1 is that in the aquatic plant purification stage, the residence time of the digested tail water in the purification tank is increased to 20 days, and it is carried out at room temperature (23 ± 2 ° C), aerobic digestion The sludge concentration in the pool is maintained at 12000-15000mg / L, and the dissolved oxygen solubility is controlled at 5.0-6.0mg / L. After aerobic digestion, the sludge organic matter degradation rate (MLVSS degradation rate) is basically the same as that of Example 1, reaching urban Pollutant discharge standard for sewage treatment plants (GB 18918-2002); digested tail water enters the purification tank, and the planting density of aquatic plants (Pteris chinensis) in the tank is maintained at 25 plants / m 2 After 20 days of adsorption and absorption by aquatic plants, the concentration of COD, TN and TP in the effluent can be reduced to 43mg / L, 14mg / L and 0.5mg / L respectively, reachi...

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