Method for co-production of carbon-based fertilizer by thermal cracking of straw

Abstract

The invention belongs to the technical field of biomass utilization and specifically provides a method for producing carbon-based fertilizer. According to the method for co-production of the carbon-based fertilizer by thermal cracking of straw, biomass pyrolysis gas is purified and separated and then subjected to combustion, and then generated high-temperature flue gas is used as a heat source fordrying and carbonizing straw particles. A part of the flue gas generated during drying is in contact with the straw particles, air around the straw particles can be replaced with the flue gas with extremely low oxygen content, an oxygen-limited environment for initial carbonization of the straw particles is creased, and improvement of the quality of carbon and carbon-based fertilizer is facilitated. At the same time, in the replacement process of the flue gas, water vapor generated during drying can also be taken away, so that energy consumption of a subsequent carbonization system is reduced, and adverse effects on the subsequent system due to presence of the water vapor are avoided.

Description

technical field

[0001] The invention belongs to the technical field of biomass utilization, and specifically provides a production method of carbon-based fertilizer Background technique

[0002] Straw, use it as treasure, discard it as harm. Statistics show that my country's annual output of agricultural and forestry waste is about 1.4 billion tons, of which the straw of corn, rice, wheat and other staple crops is as high as 700 million tons, of which less than 1 / 3 has been returned to the field, and the utilization rate of straw fertilizer is insufficient 20%. In fact, straw carbonization-returning technology is an ideal straw utilization method. Straw carbonization refers to the pyrolysis of straw under oxygen-limited and certain temperature conditions to form a stable carbon-rich product, that is, biochar. Biochar has large porosity and specific surface area, strong adsorption capacity, anti-oxidation capacity and anti-biodegradation ability, so it can be widely used in ...

Examples

Embodiment 1

[0039] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0040] The stalk particles are dried and preheated in an external heat mode, and then the dried and preheated stalks are thermally cracked under oxygen-limited conditions to obtain cracked products.

[0041] Gas-solid separation is performed on the obtained pyrolysis products to obtain pyrolysis gas and biomass charcoal. The obtained biochar is used to produce carbon-based fertilizer after crushing and cooling.

[0042] The obtained pyrolysis gas is subjected to purification treatment such as dust removal and washing in sequence, and then burned, and the flue gas generated by the combustion is transported to the drying and pyrolysis steps of straw particles, and used as a heat source.

[0043] At the same time, during drying, a part of the flue gas is in direct contact with the straw particles, replacing the air around the straw particles with flue gas, and...

Embodiment 2

[0045] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0046]First, the straw goes through a crushing, granulating or briquetting treatment system to make straw granules.

[0047] Then, the straw particles are sent into the external heat rotary drying furnace through the feeding system. The drying furnace has an inner cylinder body, an outer cylinder body and a clamping cavity sandwiched between the two. The straw particles enter the inner cylinder body of the drying furnace. Preheat and dry at 150°C.

[0048] Next, the dried and preheated straw particles are transported into the external heating rotary pyrolysis furnace. Similarly, the furnace also has an inner cylinder, an outer cylinder and a cavity sandwiched between them, and the straw particles enter the inner cylinder. The cylinder is cracked at 530°C to generate pyrolysis gas and biochar.

[0049] The generated pyrolysis gas and biochar are separated b...

Embodiment 3

[0055] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0056] First, the straw goes through a crushing, granulating or briquetting treatment system to make straw granules.

[0057] Then, the straw particles are sent into the external heat rotary drying furnace through the feeding system. The drying furnace has an inner cylinder body, an outer cylinder body and a clamping cavity sandwiched between the two. The straw particles enter the inner cylinder body of the drying furnace. Preheat and dry at 110°C.

[0058] Next, the dried and preheated straw particles are transported into the external heating rotary pyrolysis furnace. Similarly, the furnace also has an inner cylinder, an outer cylinder and a cavity sandwiched between them, and the straw particles enter the inner cylinder. The cylinder is cracked at 450°C to generate pyrolysis gas and biochar.

[0059] The generated pyrolysis gas and biochar are separated ...

technical field

[0001] The invention belongs to the technical field of biomass utilization, and specifically provides a production method of carbon-based fertilizer Background technique

[0002] Straw, use it as treasure, discard it as harm. Statistics show that my country's annual output of agricultural and forestry waste is about 1.4 billion tons, of which the straw of corn, rice, wheat and other staple crops is as high as 700 million tons, of which less than 1 / 3 has been returned to the field, and the utilization rate of straw fertilizer is insufficient 20%. In fact, straw carbonization-returning technology is an ideal straw utilization method. Straw carbonization refers to the pyrolysis of straw under oxygen-limited and certain temperature conditions to form a stable carbon-rich product, that is, biochar. Biochar has large porosity and specific surface area, strong adsorption capacity, anti-oxidation capacity and anti-biodegradation ability, so it can be widely used in ...

Examples

Embodiment 1

[0039] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0040] The stalk particles are dried and preheated in an external heat mode, and then the dried and preheated stalks are thermally cracked under oxygen-limited conditions to obtain cracked products.

[0041] Gas-solid separation is performed on the obtained pyrolysis products to obtain pyrolysis gas and biomass charcoal. The obtained biochar is used to produce carbon-based fertilizer after crushing and cooling.

[0042] The obtained pyrolysis gas is subjected to purification treatment such as dust removal and washing in sequence, and then burned, and the flue gas generated by the combustion is transported to the drying and pyrolysis steps of straw particles, and used as a heat source.

[0043] At the same time, during drying, a part of the flue gas is in direct contact with the straw particles, replacing the air around the straw particles with flue gas, and...

Embodiment 2

[0045] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0046]First, the straw goes through a crushing, granulating or briquetting treatment system to make straw granules.

[0047] Then, the straw particles are sent into the external heat rotary drying furnace through the feeding system. The drying furnace has an inner cylinder body, an outer cylinder body and a clamping cavity sandwiched between the two. The straw particles enter the inner cylinder body of the drying furnace. Preheat and dry at 150°C.

[0048] Next, the dried and preheated straw particles are transported into the external heating rotary pyrolysis furnace. Similarly, the furnace also has an inner cylinder, an outer cylinder and a cavity sandwiched between them, and the straw particles enter the inner cylinder. The cylinder is cracked at 530°C to generate pyrolysis gas and biochar.

[0049] The generated pyrolysis gas and biochar are separated b...

Embodiment 3

[0055] This embodiment provides a method for co-producing charcoal-based fertilizer by pyrolysis of straw, comprising:

[0056] First, the straw goes through a crushing, granulating or briquetting treatment system to make straw granules.

[0057] Then, the straw particles are sent into the external heat rotary drying furnace through the feeding system. The drying furnace has an inner cylinder body, an outer cylinder body and a clamping cavity sandwiched between the two. The straw particles enter the inner cylinder body of the drying furnace. Preheat and dry at 110°C.

[0058] Next, the dried and preheated straw particles are transported into the external heating rotary pyrolysis furnace. Similarly, the furnace also has an inner cylinder, an outer cylinder and a cavity sandwiched between them, and the straw particles enter the inner cylinder. The cylinder is cracked at 450°C to generate pyrolysis gas and biochar.

[0059] The generated pyrolysis gas and biochar are separated ...

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