Method for improving dissolving out of organic matter in excess sludge through combined pretreatment

A technology of excess sludge and pretreatment, which is applied in the fields of sludge treatment, biological sludge treatment, chemical instruments and methods, etc., can solve the problems of unsatisfactory sludge dissolution effect, increase the dissolution of organic matter in excess sludge, and achieve decomposition. Fast, energy-dense effects

Inactive Publication Date: 2018-11-16
HUNAN UNIV
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  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the sludge dissolution effect of simple treatment is not very ideal, and the combined pretreatment of ultrasonic and free ammonia has a synergistic effect on sludge dissolution, which can greatly improve the dissolution effect. In view of this, the present invention proposes a combination of ultrasonic and free ammonia. Pretreatment of sludge can further increase the dissolution of organic matter in excess sludge, which is more conducive to the subsequent anaerobic fermentation of sludge, and realizes resource utilization and reduction of excess sludge

Method used

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  • Method for improving dissolving out of organic matter in excess sludge through combined pretreatment
  • Method for improving dissolving out of organic matter in excess sludge through combined pretreatment
  • Method for improving dissolving out of organic matter in excess sludge through combined pretreatment

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Effect test

Embodiment 1

[0019] Firstly, the remaining sludge in the secondary sedimentation tank of the sewage treatment plant is concentrated. After concentration, the TSS of the sludge is 22820mg / l, the VSS is 13920mg / L, the SCOD is 180mg / L, and the pH is 6.82. The processing steps are as follows:

[0020] Step 1: Ultrasonic pretreatment, the ultrasonic sound energy density is 2w / ml, and the ultrasonic time is 15min;

[0021] Step 2: Free ammonia pretreatment, add a certain amount of 4mol / L ammonium chloride solution to the sludge, so that the initial ammonia nitrogen concentration in the remaining sludge is 341mg / L, use 4mol / L NaOH solution and 4mol / L The HCl solution adjusted the pH of the remaining sludge to 9 and maintained it for 48 hours, during which the temperature was controlled at 25±0.1°C (under this condition, the initial free ammonia concentration was 150mg / L), and the sludge mechanical stirring speed was 120rpm / min.

[0022] After the above-mentioned treatment, the dissolved chemical...

Embodiment 2

[0024] Firstly, the residual sludge in the secondary sedimentation tank of the sewage treatment plant is concentrated. After concentration, the VSS of the sludge is 13783mg / L, and the sludge is used as the pretreatment substrate. The processing steps are as follows:

[0025] Step 1: Ultrasonic pretreatment, the ultrasonic sound energy density is 1w / ml, and the ultrasonic time is 10min;

[0026] Step 2: Free ammonia pretreatment, add a certain amount of 4mol / L ammonium chloride solution to the sludge, so that the initial ammonia nitrogen concentration in the remaining sludge is 341mg / L, use 4mol / L NaOH solution and 4mol / L The HCl solution adjusted the pH of the remaining sludge to 9 and maintained it for 48 hours, during which the temperature was controlled at 25±0.1°C (under this condition, the initial free ammonia concentration was 150mg / L), and the sludge mechanical stirring speed was 120rpm / min.

[0027] Soluble protein reaches 892mg / L at 48h after above-mentioned treatmen...

Embodiment 3

[0029] Firstly, the residual sludge in the secondary sedimentation tank of the sewage treatment plant is concentrated. After concentration, the VSS of the sludge is 13916mg / L, and the sludge is used as the pretreatment substrate. The processing steps are as follows:

[0030] Step 1: Ultrasonic pretreatment, the ultrasonic sound energy density is 2w / ml, and the ultrasonic time is 15min;

[0031] Step 2: Free ammonia pretreatment, add a certain amount of 4mol / L ammonium chloride solution to the sludge, so that the initial ammonia nitrogen concentration in the remaining sludge is 341mg / L, use 4mol / L NaOH solution and 4mol / L The HCl solution adjusted the pH of the remaining sludge to 9 and maintained it for 48 hours, during which the temperature was controlled at 25±0.1°C (under this condition, the initial free ammonia concentration was 150mg / L), and the sludge mechanical stirring speed was 120rpm / min.

[0032] Soluble polysaccharide reaches 439mg / L at 48h after above-mentioned t...

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Abstract

The invention belongs to the technical field of treatment of solid wastes and particularly relates to a new technology for improving dissolving out of organic matter in excess sludge through pretreatment with an ultrasonic and free ammonia combined technology. The method comprises specific steps as follows: the excess sludge in a secondary sedimentation tank of a sludge treatment plant serves as afermentation substrate after gravity settling, a proper volume of sludge is subjected to ultrasonic treatment, a certain ammonia chloride solution is added to the sludge after ultrasonic treatment, pH and the temperature are controlled, free ammonia with certain concentration is produced, and the free ammonia is further pretreated. Experiments prove that dissolving out of organic matter in excesssludge can be further improved by means of the method, and the method has great significance in reduction and recycling of sludge.

Description

technical field [0001] The invention belongs to the technical field of solid waste treatment, and in particular relates to a method for improving the dissolution of excess sludge organic matter through combined pretreatment of ultrasonic waves and free ammonia. Background technique [0002] Activated sludge method is the most widely used sewage biological treatment technology at home and abroad, but a large amount of residual sludge will be generated in the process of sewage treatment, and the cost of sludge treatment is high. 20% to 60% of the sewage treatment plant has brought a very heavy operating burden. Excess sludge is an aggregate composed of bacterial micelles formed by various microorganisms and their adsorbed organic and inorganic substances, containing a large amount of water (95% to 99%), refractory organic substances, volatile substances, heavy metals and salts , as well as pathogens and parasite eggs. If the remaining sludge cannot be properly disposed of, i...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C02F11/04C02F11/00C02F101/16
CPCC02F11/00C02F11/04C02F2101/16
Inventor 王冬波黄永霞徐秋翔
Owner HUNAN UNIV
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