Method for reducing emission of potent greenhouse gas N2O in sludge earthworm composting

Abstract

The invention discloses a method for reducing emission of potent greenhouse gas N2O in sludge earthworm composting. The method comprises the following steps: step 1, arranging a buffer layer and adding earthworms into the buffer layer, wherein a matrix of the buffer layer is fermented and decomposed feces of livestock and poultry, and the conductivity of the matrix is below 5.0mS / cm; step 2, arranging an isolation net with a plurality of through holes on the buffer layer; step 3, adding sludge on the isolation net to form a reaction zone, wherein the earthworms can move between the buffer layer and the reaction zone through the through holes. According to the method, by adjusting the parameters such as the carbon-nitrogen ratio, the moisture content, the density and the like of the earthworms in the sludge earthworm composting, stabilization and reclamation of the sludge are realized, and the emission of the greenhouse gas in the process of sludge earthworm composting is greatly reduced. The method has the advantages of being high in efficiency, low in consumption and low in operating cost, achieving eco-environment protection and reducing the emission of the potent greenhouse gasN2O, therefore, the method has actual application value in reduction of secondary pollution in sludge treatment processes of sewage treatment plants in medium and small towns.

Description

technical field

[0001] The invention belongs to the field of environmental protection and relates to the problem of secondary pollution in sludge vermicomposting, in particular to a method for reducing the strong greenhouse gas N of sludge vermicomposting 2 O emission method. Background technique

[0002] With the continuous and rapid development of my country's economy and society, the sewage treatment capacity has been continuously improved, and the sludge production has also increased sharply. As of 2016, the annual output of surplus sludge in the country has reached 30 million tons. Composting is an important technology for treating sludge and making it a resource.

[0003] Through composting, the available nutrients formed after the decomposition of organic matter in the sludge are more conducive to plant absorption, and the humus produced can also improve the soil. Vermicomposting relies on the synergy between earthworms and microorganisms to decompose organic matte...

Examples

Embodiment 1

[0048] 1. Set up a buffer layer. The thickness of the buffer layer is about 5cm. It is composed of cow dung, pig manure and other substrates that earthworms like, and its conductivity is lower than 5.0mS / cm. The density of earthworms in the buffer layer is 1.2kg / m 2 .

[0049] 2. An isolation net is set on the buffer layer. The isolation net is made of hard plastic with an aperture of 0.5 cm, which is convenient for earthworms to move up and down.

[0050] 3. Take the remaining sludge after dehydration, add straw, adjust the carbon-nitrogen ratio to 20:1, and the moisture content to 70%. The mixed material should be placed in a cool place for 5 days to deodorize. After there is no obvious ammonia smell, it will be added to the reaction area.

[0051] 4. Add the deodorized sludge material directly to the isolation net with a thickness of 15cm, and cover the rear sunshade net on the top of the reaction zone. After adding materials, stimulated by fresh materials, the earthworm...

Embodiment 2

[0054] 1. Set up a buffer layer. The thickness of the buffer layer is about 5cm. It is composed of chicken, duck, goose droppings and other substrates that earthworms like, and its conductivity is lower than 5.0mS / cm. The density of earthworms in the buffer layer is 2.0kg / m 2 .

[0055] 2. An isolation net is set on the buffer layer. The isolation net is made of hard plastic with an aperture of 0.5 cm, which is convenient for earthworms to move up and down.

[0056] 3. Take the remaining sludge after dehydration, add sawdust, adjust the carbon-nitrogen ratio to 30:1, and the moisture content to 75%. The mixed material should be placed in a cool place for 5 days to deodorize. After there is no obvious ammonia smell, it will be added to the reaction area.

[0057] 4. Add the deodorized sludge material directly to the isolation net with a thickness of 10cm, and cover the rear sunshade net on the top of the reaction zone. After adding materials, stimulated by fresh materials, t...

technical field

[0001] The invention belongs to the field of environmental protection and relates to the problem of secondary pollution in sludge vermicomposting, in particular to a method for reducing the strong greenhouse gas N of sludge vermicomposting 2 O emission method. Background technique

[0002] With the continuous and rapid development of my country's economy and society, the sewage treatment capacity has been continuously improved, and the sludge production has also increased sharply. As of 2016, the annual output of surplus sludge in the country has reached 30 million tons. Composting is an important technology for treating sludge and making it a resource.

[0003] Through composting, the available nutrients formed after the decomposition of organic matter in the sludge are more conducive to plant absorption, and the humus produced can also improve the soil. Vermicomposting relies on the synergy between earthworms and microorganisms to decompose organic matte...

Examples

Embodiment 1

[0048] 1. Set up a buffer layer. The thickness of the buffer layer is about 5cm. It is composed of cow dung, pig manure and other substrates that earthworms like, and its conductivity is lower than 5.0mS / cm. The density of earthworms in the buffer layer is 1.2kg / m 2 .

[0049] 2. An isolation net is set on the buffer layer. The isolation net is made of hard plastic with an aperture of 0.5 cm, which is convenient for earthworms to move up and down.

[0050] 3. Take the remaining sludge after dehydration, add straw, adjust the carbon-nitrogen ratio to 20:1, and the moisture content to 70%. The mixed material should be placed in a cool place for 5 days to deodorize. After there is no obvious ammonia smell, it will be added to the reaction area.

[0051] 4. Add the deodorized sludge material directly to the isolation net with a thickness of 15cm, and cover the rear sunshade net on the top of the reaction zone. After adding materials, stimulated by fresh materials, the earthworm...

Embodiment 2

[0054] 1. Set up a buffer layer. The thickness of the buffer layer is about 5cm. It is composed of chicken, duck, goose droppings and other substrates that earthworms like, and its conductivity is lower than 5.0mS / cm. The density of earthworms in the buffer layer is 2.0kg / m 2 .

[0055] 2. An isolation net is set on the buffer layer. The isolation net is made of hard plastic with an aperture of 0.5 cm, which is convenient for earthworms to move up and down.

[0056] 3. Take the remaining sludge after dehydration, add sawdust, adjust the carbon-nitrogen ratio to 30:1, and the moisture content to 75%. The mixed material should be placed in a cool place for 5 days to deodorize. After there is no obvious ammonia smell, it will be added to the reaction area.

[0057] 4. Add the deodorized sludge material directly to the isolation net with a thickness of 10cm, and cover the rear sunshade net on the top of the reaction zone. After adding materials, stimulated by fresh materials, t...

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