CN111233295A - Method for cooperatively treating excess sludge by using ore washing sludge - Google Patents

Abstract

The invention discloses a method for cooperatively treating excess sludge by using ore washing sludge. Mixing the excess sludge and the rice straws according to the mass ratio of 1-5: 10, putting the mixture into a reaction kettle, heating to 60-700 ℃, keeping the temperature constant for 2-12 hours, and finally drying in an oven at 80-100 ℃ to obtain the excess sludge biochar. Adding 1-100 g of prepared excess sludge biochar into each liter of ore washing mud, uniformly stirring, pumping into a filter press through a sludge pump for dehydration, controlling the water content of the dehydrated ore washing mud to be lower than 60%, and preparing the dehydrated ore washing mud. And carrying out aerobic composting on the dewatered washed slime and the residual sludge according to the volume ratio of 0.05-1: 1, and controlling the temperature of a compost body to be 20-70 ℃ to obtain sludge compost. And mixing the prepared dewatered ore washing mud with the obtained sludge compost according to the volume ratio of 1-100: 1, and finally backfilling surface soil in a mining area, namely realizing cooperative disposal of the ore washing mud and the residual sludge. The implementation of the invention can achieve the purpose of treating wastes with wastes and obtain good economic benefit.

Description

Method for cooperatively treating excess sludge by using ore washing sludge

Technical Field

The invention belongs to the field of solid waste treatment, and particularly relates to a method for cooperatively treating excess sludge by using ore washing sludge.

Background

The washing slime contains a large amount of water which is difficult to dehydrate, so a wet discharging method is mostly adopted, and the washing slime has no better treatment mode for the bauxite washing slime at home and abroad at present except stacking and sealing storage. As the mining of mineral deposits increases year by year, the disposal and disposal of wash sludge is at hand.

In addition, a large amount of sludge is generated in the sewage treatment process of the sewage plant, and the effective treatment of the sludge becomes a problem to be solved urgently. The compost is an important means for recycling the sludge, the sludge and green wastes are mixed and composted to contain a large amount of organic matters and nutrient elements, and the compost can be used for repairing and improving dewatered slime. The bauxite mining causes the farmland to be damaged, and the main purpose of reclamation after mining is to return the bauxite to farmers, so that the requirement on the reclamation quality is higher. However, the surface covering soil has high heavy metal content, and the main restriction factors of soil structure damage and low fertility are also adopted. Therefore, the dehydrated slime is mixed with the excess sludge of the sewage treatment plant or the green waste compost and then backfilled into a mining area, and the conversion of pollutants in the mixture is expected to be accelerated and the physical and chemical properties of soil are improved.

Disclosure of Invention

The invention aims to provide a method for cooperatively treating excess sludge by using ore washing sludge.

The method comprises the following specific steps:

(1) mixing the excess sludge and the rice straws according to the mass ratio of 1-5: 10, heating the mixed excess sludge and the rice straws to 60-700 ℃ in a reaction kettle, maintaining the constant temperature for 2-12 hours, and finally drying in an oven at 80-100 ℃ to obtain the excess sludge biochar.

(2) And (2) adding 1-100 g of the excess sludge biochar prepared in the step (1) into each liter of ore washing mud, uniformly stirring, pumping into a filter press through a sludge pump for dehydration, controlling the water content of the dehydrated ore washing mud to be lower than 60%, and preparing the dehydrated ore washing mud.

(3) Carrying out aerobic composting on the dewatered washed slime prepared in the step (2) and the excess sludge according to the volume ratio of 0.05-1: 1, curing the excess sludge by controlling the temperature of a compost body to be 20-70 ℃, and further dewatering the washed slime to obtain sludge compost.

(4) And (3) mixing the dewatered washed slime obtained in the step (2) with the sludge compost obtained in the step (3) according to the volume ratio of 1-100: 1, and finally backfilling surface soil in a mining area, namely realizing the cooperative treatment of the washed slime on the residual sludge.

The method is simple to operate, realizes the treatment of waste by cooperatively treating the excess sludge through the ore washing sludge, realizes good economic benefit, and is beneficial to popularization and use.

Detailed Description

Example (b):

(1) mixing the excess sludge and the rice straws according to the mass ratio of 3:10, heating the mixed excess sludge and the rice straws to 500 ℃ in a reaction kettle, maintaining the constant temperature for 8 hours, and finally drying in a drying oven at 90 ℃ to obtain the excess sludge biochar.

(2) And (2) adding 50 g of the excess sludge biochar prepared in the step (1) into each liter of ore washing mud, uniformly stirring, pumping into a filter press through a sludge pump for dehydration, controlling the water content of the dehydrated ore washing mud to be 50%, and preparing the dehydrated ore washing mud.

(3) Carrying out aerobic composting on the dewatered washed slime prepared in the step (2) and the excess sludge according to the volume ratio of 0.5:1, curing the excess sludge by controlling the temperature of a compost body to be 45 ℃, and further dewatering the washed slime to obtain sludge compost.

(4) And (3) mixing the dewatered washed slime obtained in the step (2) with the sludge compost obtained in the step (3) according to the volume ratio of 50:1, and finally backfilling surface soil of a mining area to realize the cooperative treatment of excess sludge by the washed slime.

Claims (1)

1. A method for cooperatively treating excess sludge by washing sludge is characterized by comprising the following specific steps:

(1) mixing the excess sludge and the rice straws according to the mass ratio of 1-5: 10, heating the mixed excess sludge and the rice straws to 60-700 ℃ in a reaction kettle, maintaining the constant temperature for 2-12 hours, and finally drying in an oven at 80-100 ℃ to obtain excess sludge biochar;

(2) adding 1-100 g of the excess sludge biochar prepared in the step (1) into each liter of ore washing mud, uniformly stirring, pumping into a filter press through a sludge pump for dehydration, controlling the water content of the dehydrated ore washing mud to be lower than 60%, and preparing the dehydrated ore washing mud;

(3) carrying out aerobic composting on the dewatered washed slime prepared in the step (2) and the excess sludge according to the volume ratio of 0.05-1: 1, curing the excess sludge by controlling the temperature of a compost body to be 20-70 ℃, and further dewatering the washed slime to obtain sludge compost;

(4) and (3) mixing the dewatered washed slime obtained in the step (2) with the sludge compost obtained in the step (3) according to the volume ratio of 1-100: 1, and finally backfilling surface soil in a mining area, namely realizing the cooperative treatment of the washed slime on the residual sludge.