CN108007107A - A kind of solar energy desiccation factory concurrent heating system and application method - Google Patents

Abstract

The invention discloses an auxiliary heating system of a solar drying plant and a using method thereof. It includes a ventilator installed in the drying greenhouse and a floor heating system laid in the drying greenhouse. A steam-air heat exchanger is installed on one side of the drying greenhouse. The air input end of the steam-air heat exchanger is connected to a blower. The steam input end of the heater is connected to the boiler system through the steam valve, the air outlet end of the steam-air heat exchanger is connected to the fan through the air pipe, the water outlet end of the steam-air heat exchanger is connected to the floor heating system through the water pipe, the fan, the blower and the steam valve All are controlled by a unified control system. After adopting the above system and method, the drying effect of the biogas residue is greatly improved. After the steam heat exchange, the condensed high-temperature hot water enters the floor heating system and continues to heat the biogas residue on the drying bed. After the heat exchange with the biogas residue is completed, the low-temperature cold water is condensed Recycling and recycling, with the advantages of steam waste heat recovery, water recycling, etc., completely realized the real energy saving and emission reduction.

Description

A solar drying plant auxiliary heating system and its application method

technical field

The invention relates to an auxiliary heating system of a solar drying plant, in particular to an auxiliary heating system of a solar drying plant, belonging to the technical field of energy saving and environmental protection.

Background technique

In the process of co-processing of kitchen waste and sludge, the solar drying plant is an important area for resource utilization of the mixture of kitchen waste and sludge after gas production. Solar drying refers to the use of traditional greenhouse drying technology. Combined with the development of modern automation technology, solar energy, a clean energy, is used as the main energy source for biogas residue drying, and the process of using solar energy to dry biogas residues is odorless and free of three wastes, and can achieve zero-emission clean production, with a water content of 60-80% After the left and right biogas residues are dried by solar energy, the water content of the biogas residues can be reduced to about 30%. After drying, they can be used as nutrient soil to achieve the goals of energy saving, emission reduction, and resource utilization.

Solar drying plants generally have equipment and facilities such as solar drying greenhouses, distributing machines, sludge turning machines, and ventilators. The dehydrated biogas residue is sent to the drying greenhouse through the conveyor, and is evenly arranged on the drying bed by the distribution machine. The turning machine and the fan continuously mix, crush and ventilate the biogas residue to realize drying. In summer, when there is sufficient sunshine, the temperature of the greenhouse can reach above 50°C, and the moisture content of the biogas residue can be reduced to 30%, and the drying effect is obvious. The moisture content of the material is only about 55%. In order to solve this problem, many manufacturers increase the air temperature inside the drying greenhouse by adding air conditioners, heat pumps and other equipment. Facts have proved that although the drying effect has been improved, the power consumption is too large. The significance of energy saving and emission reduction.

Contents of the invention

The technical problem to be solved by the present invention is to provide an auxiliary heating system for a solar drying plant with low energy consumption, good drying effect, and a thorough realization of energy saving and emission reduction and its use method.

In order to solve the above technical problems, the auxiliary heating system of the solar drying plant of the present invention includes a ventilator installed in the drying booth and a floor heating system laid in the drying booth, and a steam-air heat exchanger is arranged on one side of the drying booth. The air input end of the steam-air heat exchanger is connected with a blower that can make external air enter the steam-air heat exchanger, the steam input end of the steam-air heat exchanger is connected to the boiler system through a steam valve, and the air outlet of the steam-air heat exchanger The outlet end of the steam-air heat exchanger is connected to the floor heating system through the water pipe. The ventilator, blower and steam valve are all controlled by a unified control system. The ventilator, blower and steam valve are controlled by the control system and can be used Air and steam enter the steam-air heat exchanger to heat and exchange heat. After being heated by the steam-air heat exchanger, the steam enters the drying greenhouse through the fan for forced convection with the biogas residue, and is heated by the steam-air heat exchanger. The steam water generated by the heat exchange is circulated through the floor heating system to heat and dry the biogas residue in the greenhouse and flows to the boiler system for recycling.

The drying booth is provided with a drying bed, and the steam-air heat exchanger is installed at the end of the drying bed in the drying booth.

The steam-air heat exchanger is a shell-and-tube heat exchanger or a heat pipe heat exchanger.

The floor heating system is buried under the drying bed of the drying greenhouse, and the floor heating system is arranged in a U shape and covers the entire drying bed.

A method for using the auxiliary heating system of the above-mentioned solar drying plant, comprising the following steps:

A: Turn on the blower and let the cold air enter the steam-air heat exchanger through the air input port;

B: The steam valve is opened, the steam is passed into the steam-air heat exchanger, and exchanges heat with the cold air, so that the temperature of the cold air rises, the high-temperature steam is cooled into high-temperature hot water and flows into the floor heating system, and the high-temperature hot water enters the floor heating system. The heat is transferred to the biogas residue on the surface of the drying bed, and at the same time, the heated high-temperature air is forced to convect with the biogas residue through the fan in the drying greenhouse;

C: By turning off the control system, stop the whole process of heat exchange and heating.

In the step B, the high-temperature hot water passes through the floor heating system to reduce the temperature and condense into low-temperature cold water, which is then returned to the boiler system for further recycling.

After adopting the above system and method, on the basis of the traditional solar drying plant, the remaining steam in the plant area is used to heat the air through the steam-air heat exchanger, and then the high-temperature air is sent to the drying plant to participate in production through the blower, which greatly improves the dryness of the biogas residue. The condensed high-temperature hot water after the steam heat exchange enters the floor heating system and continues to heat the biogas residue on the drying bed. After the heat exchange with the biogas residue is completed, the condensed low-temperature cold water is recycled and recycled. This technical solution is different from traditional air conditioners, heat pumps, etc. Compared with auxiliary heating equipment, it avoids the disadvantage of excessive power consumption of the existing auxiliary heating system, and also has the advantages of steam waste heat recovery, water recycling, etc., and thoroughly realizes real energy saving and emission reduction.

Description of drawings

Fig. 1 is a structural schematic diagram of the auxiliary heating system of the solar drying plant of the present invention.

Detailed ways

The auxiliary heating system and usage method of the solar drying plant of the present invention will be further described in detail in conjunction with the accompanying drawings and specific implementation methods.

The present invention aims at the problem of unsatisfactory drying effect caused by low winter temperature and insufficient light in solar drying plants. It reconceives that the remaining steam is used to heat the air through a steam-air heat exchanger, and combined with floor heating to increase the internal temperature of the drying plant, thereby improving Biogas residue drying efficiency, the technical scheme adopted is as follows:

As shown in the figure, the auxiliary heating system of the solar energy drying plant of the present invention includes a ventilator 1 installed in the drying booth and a floor heating water pipe 2 laid in the drying booth. One side is provided with a steam-air heat exchanger 3, the steam-air heat exchanger is the main equipment for heat exchange, the steam-air heat exchanger 3 is installed at the end of the drying bed of the drying greenhouse, which does not affect the normal operation of the turning machine. The air input end of the steam-air heat exchanger 3 is connected with a blower 4 capable of allowing external air to enter the steam-air heat exchanger 3, and the steam input end of the steam-air heat exchanger 3 is connected to the boiler system through a steam valve 5, and the steam-air heat exchanger The air outlet end of the heater 3 is connected to the fan 1 through the air pipe, and the water outlet end of the steam-air heat exchanger 3 is connected to the floor heating water pipe 2 through the water pipe. The floor heating water pipe 2 is buried under the drying bed of the drying greenhouse, and the floor heating water pipe 2 is U-shaped. Arranged all over the entire drying bed, and considering the heat transfer effect should not be buried deep, the ventilator 1, blower 4 and steam valve 5 are all controlled by a unified control system, and the ventilator 1, blower 4 and steam valve 5 are controlled by the control system and The air and steam can enter the steam-air heat exchanger 3 for heating and heat exchange, and the steam heated and exchanged by the steam-air heat exchanger 3 enters the drying greenhouse through the ventilator 1 for forced convection with the biogas residue, and passes through the steam The steam water generated by the heat exchange of the air heat exchanger 3 is circulated through the floor heating water pipe 2 to heat and dry the biogas slag in the greenhouse and flow to the boiler system for recycling.

Wherein, said steam-to-air heat exchanger 3 is preferably a shell-and-tube heat exchanger or a heat pipe heat exchanger, but is not limited thereto. The main function of said blower is to draw cold air outside the solar drying greenhouse into The steam-air heat exchanger blows the hot air after heat exchange into the drying greenhouse, and then the hot air passes through the original fan 1 of the drying plant to dry the biogas residue.

Through the above structural design, high-temperature and high-pressure steam enters the steam-air heat exchanger and exchanges heat with cold air to become high-temperature water, and the hot water flowing out of the steam-air heat exchanger enters the floor heating water pipe to continuously heat the biogas residue on the surface of the drying bed. Since the floor heating uses clean steam condensate, the cold water can be recycled and recycled after the heat exchange with biogas residues. Only the blower consumes a small amount of electric energy. Compared with traditional air conditioning and heat pump auxiliary heating systems, it saves a lot of electric energy and costs more. It is cheap, and steam water can be recycled at the same time, which realizes real energy saving and emission reduction. In addition, the invention can be externally adapted to various types of solar drying plants.

A method for using the auxiliary heating system of the above-mentioned solar drying plant, comprising the following steps:

A: Turn on the blower and let the cold air enter the steam-air heat exchanger through the air input port;

B: The steam valve is opened, the steam is passed into the steam-air heat exchanger, and exchanges heat with the cold air, so that the temperature of the cold air rises, the high-temperature steam is cooled into high-temperature hot water and flows into the floor heating water pipe 2, and the high-temperature hot water enters the floor heating water pipe, The heat is transferred to the biogas residue on the surface of the drying bed to increase the temperature. At the same time, the heated high-temperature air is forced to convect with the biogas residue through the fan in the drying greenhouse to increase the internal temperature of the drying plant and accelerate the drying of the biogas residue. Drying speed, finally reduce the moisture content of biogas residue;

C: Stop the whole process of heat exchange and heating by closing the control system. The control system is an automatic control system, which is mainly used to control the remote or manual opening of the equipment, so as to connect various equipment and maintain a constant temperature in the drying plant. Control, so through the control system, it can be operated manually on site or remotely, and can also be automatically started and stopped according to the opening of the fan in the factory.

Further, in step B, the high-temperature hot water passes through the floor heating system and then lowers its temperature to condense into low-temperature cold water and returns to the boiler system for further recycling.

Taking an organic matter treatment center in a city in Jiangsu as an example, the kitchen waste and domestic sludge are co-processed. The mixture is anaerobically fermented in an anaerobic tank to produce biogas, which is purified and connected to the grid for use. About 60% is sent to the solar drying plant for further drying.

When the temperature is low in winter and the light is insufficient, as shown in Figure 1: when the internal ventilator 1 of the drying plant is turned on, the blower 4 of the auxiliary heating system is turned on in conjunction, the steam valve 5 is turned on, and the saturated dry steam at 150°C enters the steam-air heat exchanger 3, the air is heated to 50-60°C, and sent by the blower to the drying plant through the air duct to participate in the drying of biogas residues, and the steam in the heat exchanger is cooled to high-temperature hot water at about 80°C, which enters the floor heating system for circulation heating The biogas slag on the surface of the drying bed, the steam water after the heat exchange is about 25°C, flows out of the floor heating system to the boiler room in the plant for recycling, when the internal ventilation fan 1 of the drying plant is turned off, the system will automatically shut down 1 After using the auxiliary heating system , The internal temperature of the drying plant can reach above 45°C, and the moisture content of the biogas residue can be reduced to 30%.

Claims (6)

1. a kind of solar energy desiccation factory concurrent heating system, including the ventilation blower installed in desiccation greenhouse（1）And paving in desiccation greenhouse If ground heating system（2）, it is characterised in that：The side of the desiccation greenhouse is provided with steam air heat exchanger（3）, the steam Air heat exchanger（3）Air input be connected with extraneous air can be made to enter steam air heat exchanger（3）Interior air blast Machine（4）, the steam air heat exchanger（3）Steam input terminal pass through steam valve（5）Steam generator system is connected, the steam is empty Gas heat exchanger（3）Outlet air end by air hose connection ventilation blower（1）, the steam air heat exchanger（3）Water outlet pass through water Pipe connects ground heating system（2）, the ventilation blower（1）, air blower（4）And steam valve（5）Pass through unified control system control System, the ventilation blower（1）, air blower（4）And steam valve（5）By control system control and can make air and steam into Enter to steam air heat exchanger（3）Interior heating heat exchange, by the steam air heat exchanger（3）Steam after heating heat exchange passes through Ventilation blower（1）Enter in desiccation greenhouse and carry out forced convertion with biogas residue, by the steam air heat exchanger（3）Heating heat exchange The steam water of generation passes through ground heating system（2）Biogas residue in circulating-heating desiccation greenhouse and flowing in steam generator system recycles.

2. solar energy desiccation factory described in accordance with the claim 1 concurrent heating system, it is characterised in that：The desiccation greenhouse is provided with dry Change bed, the steam air heat exchanger（3）Installed in the end of the drying bed of desiccation greenhouse.

3. according to the solar energy desiccation factory concurrent heating system described in claim 1 or 2, it is characterised in that：The steam air heat exchange Device（3）For shell-and-tube heat exchanger or heat-pipe heat exchanger.

4. solar energy desiccation factory described in accordance with the claim 3 concurrent heating system, it is characterised in that：The ground heating system（2）It is embedded in Under the drying bed of desiccation greenhouse, the ground heating system（2）It is covered with whole drying bed for floor heating water pipe and the arrangement that takes the shape of the letter U.

A kind of 5. application method using the solar energy desiccation factory concurrent heating system as described in one of claim 1-4, it is characterised in that Comprise the following steps：

A：Air blower is opened, cold air is entered in steam air heat exchanger by air input；

B：Steam valve is opened, and steam is passed through to steam air heat exchanger, is exchanged heat with cold air, is raised air temperature, High-temperature steam is cooled to high-temperature-hot-water and flows into ground heating system（2）Interior, high-temperature-hot-water enters ground heating system, transfers heat to desiccation Biogas residue on bed surface, at the same time, the high temperature air after being heated, is forced by the ventilation blower in desiccation greenhouse with biogas residue Convection current；

C：By closing control system, stop heat exchange whole process.

6. according to the application method of the solar energy desiccation factory concurrent heating system described in claim 5, it is characterised in that the step B In, high-temperature-hot-water forms to reduce temperature and return in steam generator system after ground heating system continues cycling through utilization.