CN107652995B - A method for preparing biogas by rapid pyrolysis of distiller's grains - Google Patents

Abstract

A kind of method that vinasse fast pyrogenation prepares biological flue gas, regulate and control downdraft rapid microwave pyrolytic reaction device, set 750-1200 DEG C of target pyrolysis temperature, 200-600 DEG C of intended catalyzed temperature, adjusting microwave power is 1000-9000W, charging rate is 5-50kg/h, and mixing speed is 20-120 r/min；When pyrolysis temperature, catalytic temperature reach the target value of setting, vinasse are continuously added in microwave reaction chamber by screw-feeder, blender pull-type agitation up and down；Pyrolysis residue is discharged into storage slag device；For pyrogenic steam through catalytic reforming, bio-fuel-oil enters liquid header, and biological flue gas is collected by gas collector.The present invention can operate continuously industry, be suitble to industrialized production, the reaction time is short, and side reaction is few, and pyrogenic steam can carry out effective catalytic reforming, improves the quality of biological flue gas.

Description

A method for preparing biogas by rapid pyrolysis of distiller's grains

technical field

The invention relates to a method for fast microwave pyrolysis of distiller's grains to convert high value-added biogas.

Background technique

The most important problem in the production of the alcohol industry and the brewing industry is the disposal of distiller's grain waste liquid and waste residue. According to statistics, every 1 L of alcohol produced can produce 9-14 L of waste liquid, and every 1 t of liquor produced produces about 10 t Waste grains, 15 t waste water. Therefore, proper distiller's grains treatment methods are of great significance to the healthy development of the alcohol industry. According to statistics, my country's annual output of various distiller's grains is as high as 27 million tons, with a large amount of resources and great development value. It is of great significance to vigorously promote the comprehensive utilization technology of distiller's grains.

In recent years, with the rapid development of the national economy, my country's oil resources have increased, and my country's dependence on foreign oil has increased year by year. The fundamental way to solve the problem of insufficient oil resources lies in the development and utilization of various renewable energy sources including biomass. Biomass is the most common clean and renewable energy on the earth. Its raw material resources are abundant and its development potential is huge. The development of biomass gasification technology on this basis will not only bring economic benefits, but also promote the development of environmental protection. The prospect is very promising.

With the continuous development and maturity of microwave technology, the research on the preparation of biosyngas by microwave pyrolysis and gasification of biomass has received extensive attention. Using microwave heating, not only the heating rate is fast, resulting in high process efficiency, but also by reducing the amount of _O2 used in the gasification system, the amount of _CO2 produced in the gasification process is reduced, and the generated syngas has a higher effective gas concentration, especially more High H/C ratio, low _O2 consumption also makes gas generation more efficient. This hydrogen-rich, high effective component concentration syngas is also more suitable for syngas biosynthesis applications.

Contents of the invention

The purpose of the present invention is to provide a method for preparing biogas by rapid pyrolysis of distiller's grains, which has simple process, continuous operability and is suitable for industrial production.

The present invention is achieved through the following technical solutions.

A method for preparing biogas by rapid pyrolysis of distiller's grains according to the present invention comprises the following steps.

Regulate the downdraft rapid microwave pyrolysis reaction device, set the target pyrolysis temperature to 750-1200°C, target catalytic temperature to 200-600°C, adjust the microwave power to 1000-9000W, feed rate to 5-50kg/h, stirring speed 20-120 r/min.

When the pyrolysis temperature and catalytic temperature reach the set target value, the distiller's grains are continuously fed into the microwave reaction chamber through the screw feeder, and at the same time, the agitator stirs up and down.

The distiller's grains are rapidly heated and pyrolyzed, and the resulting residue is discharged into the slag storage through the orifice plate. An ash-proof partition is installed under the orifice plate to prevent the residue from entering the gas outlet. The pyrolysis steam passes through the high-temperature spherical silicon carbide bed under the negative pressure of the air pump. It enters the gas outlet on the upper part of the slag accumulator, then enters the catalyst filling pipe for catalytic reforming, and finally condenses into biofuel through the condenser and enters the liquid collector, and the non-condensable biogas is collected through the gas collector.

The downdraft fast microwave pyrolysis reaction device of the present invention consists of a control system (1), a screw feeder (2), an agitator (3), an insulation layer (4), a microwave magnetron (5), a microwave Reaction chamber (6), thermocouple (7), spherical silicon carbide (8), orifice plate (9), slag storage (10), ash-proof partition (11), gas outlet (12), catalyst filling pipe ( 13), heating jacket (14), condenser (15), liquid collector (16), air pump (17), gas collector (18).

The screw feeder (2) is connected to the upper part of the microwave reaction chamber (6). Inside the microwave reaction chamber (6) there are agitator (3) and spherical silicon carbide (8). The tube (5), the lower part is an orifice (9), the outer wall of the microwave reaction chamber (6) is embedded with a thermocouple (7), the slag storage (10) is connected with the microwave reaction chamber (6), and there is an orifice (9) in the middle ), the inside of the slag container (10) is provided with an ash-proof partition (11), the upper part is provided with a gas outlet (12), the catalyst filling pipe (13) is connected with the gas outlet (12), and the outside of the catalyst filling pipe (13) is The heating jacket (14), the condenser (15) is connected with the catalyst filling pipe (13), the liquid collector (16) is provided at the lower part of the condenser (15), the air pump (17) is connected with the condenser (15), and the air pump (17) The gas outlet is connected to the gas collector (18).

The control system (1) is connected to the microwave magnetron (5), the screw feeder (2), the stirrer (3), the thermocouple (7) and the heating mantle (14) respectively through cables to regulate the microwave power, Feed speed, stirring speed, pyrolysis temperature and catalytic temperature.

The material of the thermal insulation layer (4) is aluminum silicate fiber.

The number of the microwave magnetrons (5) is 2-10, the output power of each is 1-1.5 Kw, the frequency is 2450MHz, and the cooling method is water cooling.

The material of the microwave reaction cavity (6) is high temperature resistant wave transparent ceramics.

The diameter of the spherical silicon carbide (8) is 2-4cm.

The hole diameter of the hole plate (9) is 1-3cm.

The advantage of the device of the present invention is that it has continuous operability and is suitable for industrial production. The distiller's grains quickly reach the pyrolysis temperature under the action of the high-heat spherical silicon carbide bed, shorten the reaction time, and reduce the occurrence of side reactions. The pyrolysis steam passes through the high-heat spherical silicon carbide bed. layer to promote the decomposition of tar, while prolonging the service life of the catalyst through external catalysis, and effectively catalytically reforming the pyrolysis steam to effectively improve the quality of biogas.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Among them, 1 is the control system, 2 is the screw feeder, 3 is the agitator, 4 is the insulation layer, 5 is the microwave magnetron, 6 is the microwave reaction chamber, 7 is the thermocouple, 8 is spherical silicon carbide, 9 is Orifice plate, 10 is a slag storage device, 11 is an ash-proof partition, 12 is an air outlet, 13 is a catalyst filling pipe, 14 is a heating jacket, 15 is a condenser, 16 is a liquid collector, 17 is an air pump, 18 is gas collector.

Detailed ways

The present invention will be further illustrated by the following examples in conjunction with the accompanying drawings.

Example 1.

As shown in Figure 1, the target pyrolysis temperature is set to 800 °C, the target catalytic temperature is 250 °C through the control system, the microwave power is adjusted to 8000 W, the feed rate is 20 kg/h, and the stirring speed is 60 r/min. When the set target temperature is reached, the distiller's grains are continuously added into the microwave reaction chamber through the screw feeder, and the stirrer is pulled up and down to stir, the distiller's grains heat up rapidly and pyrolyze, and the residue generated is discharged into the residue storage through the orifice plate. The ash-proof partition prevents the residue from entering the gas outlet. The pyrolysis steam enters the upper gas outlet of the slag storage through the high-temperature spherical silicon carbide bed under the negative pressure of the air pump, and then enters the catalyst filling tube for catalytic reforming, and finally passes through the condenser. The condensed biofuel enters the liquid collector, and the non-condensable biogas is collected by the gas collector. The gasification efficiency is 70%, the tar content in the gas is 0.9g/m ³ , and the hydrogen, carbon monoxide and methane contents are 80%.

Example 2.

As shown in Figure 1, the target pyrolysis temperature is set to 950 °C, the target catalytic temperature is 300 °C through the control system, the microwave power is adjusted to 8000 W, the feed rate is 20 kg/h, and the stirring speed is 60 r/min. When the set target temperature is reached, the distiller's grains are continuously added into the microwave reaction chamber through the screw feeder, and the stirrer is pulled up and down to stir, the distiller's grains heat up rapidly and pyrolyze, and the residue generated is discharged into the residue storage through the orifice plate. The ash-proof partition prevents the residue from entering the gas outlet. The pyrolysis steam enters the upper gas outlet of the slag storage through the high-temperature spherical silicon carbide bed under the negative pressure of the air pump, and then enters the catalyst filling tube for catalytic reforming, and finally passes through the condenser. The condensed biofuel enters the liquid collector, and the non-condensable biogas is collected by the gas collector. The gasification efficiency is 88%, the tar content in the gas is 0.5g/m ³ , and the hydrogen, carbon monoxide and methane contents are 94%.

Example 3.

As shown in Figure 1, the target pyrolysis temperature is set to 1100 °C, the target catalytic temperature is 300 °C through the control system, the microwave power is adjusted to 8000 W, the feed rate is 30 kg/h, and the stirring speed is 60 r/min. When the set target temperature is reached, the distiller's grains are continuously added into the microwave reaction chamber through the screw feeder, and the stirrer is pulled up and down to stir, the distiller's grains heat up rapidly and pyrolyze, and the residue generated is discharged into the residue storage through the orifice plate. The ash-proof partition prevents the residue from entering the gas outlet. The pyrolysis steam enters the upper gas outlet of the slag storage through the high-temperature spherical silicon carbide bed under the negative pressure of the air pump, and then enters the catalyst filling tube for catalytic reforming, and finally passes through the condenser. The condensed biofuel enters the liquid collector, and the non-condensable biogas is collected by the gas collector. The gasification efficiency is 90%, the tar content in the gas is 0.4g/m ³ , and the hydrogen, carbon monoxide and methane contents are 95%.

Claims (1)

1. A method for preparing biogas by rapid pyrolysis of distiller's grains, is characterized in that as follows: Regulate the downdraft rapid microwave pyrolysis reaction device, set the target pyrolysis temperature to 750-1200°C, target catalytic temperature to 200-600°C, adjust the microwave power to 1000-9000W, feed rate to 5-50kg/h, stirring speed 20-120 r/min; When the pyrolysis temperature and catalytic temperature reach the set target value, the distiller's grains are continuously fed into the microwave reaction chamber through the screw feeder, and at the same time, the agitator stirs up and down; The distiller's grains are rapidly heated and pyrolyzed, and the resulting residue is discharged into the slag storage through the orifice; the pyrolysis steam enters the upper gas outlet of the slag storage through the high-temperature spherical silicon carbide bed under the negative pressure of the air pump, and then enters the catalyst filling tube Catalytic reforming, and finally condensed into biofuel through the condenser and enter the liquid collector, and the non-condensable biogas is collected through the gas collector; The downdraft rapid microwave pyrolysis reaction device consists of a control system, a screw feeder, an agitator, an insulation layer, a microwave magnetron, a microwave reaction chamber, a thermocouple, spherical silicon carbide, an orifice plate, a slag storage device, Composed of dust-proof partition, gas outlet, catalyst filling pipe, heating jacket, condenser, liquid collector, air pump, and gas collector; The screw feeder is connected to the upper part of the microwave reaction chamber. There are stirrers and spherical silicon carbide in the microwave reaction chamber. The outer part is an insulation layer and a microwave magnetron in turn. The lower part is an orifice plate. Thermocouples are embedded in the outer wall of the microwave reaction chamber. The container is connected with the microwave reaction chamber, and there is an orifice plate in the middle. There is an ash-proof partition inside the slag container, and an air outlet is arranged on the upper part. The catalyst filling pipe is connected with the gas outlet. The filling pipe is connected, the lower part of the condenser is provided with a liquid collector, the air pump is connected to the condenser, and the gas outlet of the air pump is connected to the gas collector; The control system is connected to the microwave magnetron, screw feeder, stirrer, thermocouple, and heating mantle through cables to regulate microwave power, feeding speed, stirring speed, pyrolysis temperature and catalytic temperature.