阅读说明：本技术 一种堆肥反应器均匀通风系统 (Composting reactor uniform ventilation system ) 是由 沈玉君 程琼仪 孟海波 赵立欣 程红胜 于 2019-11-04 设计创作，主要内容包括：本发明涉及一种堆肥反应器均匀通风系统。通风系统包括通风装置、通风控制装置和温度控制装置,通风装置包括风机、通风管道和出风口,通风管道设于堆肥反应器的下方,通风管道上设有通风孔；出风口设于堆肥反应器的上方；风机设于通风管道的入口；通风控制装置包括变频器、流量计和第一控制器,变频器与风机及控制器连接,流量计设于通风管道上,流量计与控制器相连,控制器根据流量计测得的通风流量计算通风管道内的气流速度,并对变频器进行控制；温度控制装置包括温度计、加热器及第二控制器,温度计的探头安装于堆肥反应器内部,温度计与第二控制器连接,第二控制器与加热器连接。本发明能够控制进风温度、风管上小孔的出风角度及出风速度。(The invention relates to a uniform ventilation system of a composting reactor. The ventilation system comprises a ventilation device, a ventilation control device and a temperature control device, wherein the ventilation device comprises a fan, a ventilation pipeline and an air outlet; the air outlet is arranged above the composting reactor; the fan is arranged at the inlet of the ventilating duct; the ventilation control device comprises a frequency converter, a flowmeter and a first controller, wherein the frequency converter is connected with the fan and the controller, the flowmeter is arranged on the ventilation pipeline and is connected with the controller, and the controller calculates the air flow speed in the ventilation pipeline according to the ventilation flow measured by the flowmeter and controls the frequency converter; the temperature control device comprises a thermometer, a heater and a second controller, wherein a probe of the thermometer is arranged in the composting reactor, the thermometer is connected with the second controller, and the second controller is connected with the heater. The invention can control the air inlet temperature, the air outlet angle of the small hole on the air pipe and the air outlet speed.)

1. A composting reactor uniform ventilation system, characterized in that the ventilation system comprises ventilation means, ventilation control means and temperature control means, wherein,

the ventilation device comprises a fan, a ventilation pipeline and an air outlet, the ventilation pipeline is arranged below the composting reactor, and the ventilation pipeline is provided with a ventilation hole; the air outlet is arranged above the composting reactor; the fan is arranged at the inlet of the ventilating duct;

the ventilation control device comprises a frequency converter, a flow meter and a first controller, wherein the frequency converter is connected with the fan and the controller, the flow meter is arranged on the ventilation pipeline, the flow meter is connected with the controller, the controller calculates the air flow velocity in the ventilation pipeline according to the ventilation flow measured by the flow meter and controls the frequency converter so as to adjust the air flow velocity in the ventilation pipeline;

the temperature control device comprises a thermometer, a heater and a second controller, a probe of the thermometer is installed inside the composting reactor, the thermometer is connected with the second controller, the second controller is connected with the heater, the heater is connected with the fan, and the second controller regulates and controls the heater according to the temperature measured by the thermometer;

the first controller and the second controller are the same controller or different controllers.

2. A composting reactor uniform ventilation system as claimed in claim 1, characterised in that the air outlet speed of the vent holes is greater than or equal to 10m/s, and the included angle between the air outlet angle of the vent holes and the axis of the air pipe in which the vent holes are located is greater than or equal to 80 °.

3. The composting reactor uniform ventilating system of claim 2, wherein the flow velocity vd of the air flow in the duct where the vent is located is 1.7m/s or less, and the flow velocity vj generated by the static pressure difference of the air flow in the duct where the vent is located is 9.8m/s or more.

4. A composting reactor uniform ventilating system as claimed in claim 3, characterised in that the ventilating duct comprises a main duct and branch ducts, the main duct is connected with the ventilating control means, the branch ducts are in a group, a group of the branch ducts are respectively connected with the main duct, and the ventilating holes are provided in the branch ducts.

5. A composting reactor plenum as claimed in claim 3, characterised in that the ventilation holes are provided in the upper half of the circumference of the branch pipe, the ventilation holes being provided in one or more rows in the axial direction of the branch pipe.

6. A composting reactor plenum as claimed in claim 4 or 5, characterised in that the total pressure provided by the fan is 63.8n Pa or more, where n is the number of branches.

7. A composting reactor plenum as claimed in claim 4 or 5 wherein the branch pipes are connected to the main pipe by means of an arcuate flare.

8. A composting reactor plenum as claimed in claim 4 or 5 wherein there are two temperature gauges, one at the air inlet of the first and last branch and one at the front of the first vent of each branch.

9. A composting reactor plenum as claimed in claim 4 or 5, characterised in that the ratio of the diameter of the main pipes to the branch pipes is greater than 1 and equal to or less than 2.

10. A composting reactor uniform ventilating system as claimed in any one of claims 1 to 5, characterised in that the ventilating device further comprises a closed space which is arranged below the composting reactor and is communicated with the composting reactor through a circulating hole, and the ventilating duct is arranged in the closed space.

Technical Field

The invention relates to the technical field of compost ventilation, in particular to a uniform ventilation system of a compost reactor.

Background

Aeration is one of the important factors affecting the composting effect, providing oxygen to the compost mass and removing moisture and heat. When the temperature of the inlet air is too low, the excessive heat inside the compost body can be taken away by ventilation, and the composting reaction can not be normally carried out. When the air quantity is not enough, the stack body can be subjected to anaerobic fermentation. Therefore, to achieve a good composting effect, the control of the inlet air temperature and the reasonable design of the ventilation system are very important.

The ventilation system design mainly comprises ventilation quantity selection, ventilation pipeline design and the like. The research on the ventilation volume is mature, and the ventilation pipeline which plays a main role in regulating and controlling the air flow in the stack body is mostly based on the design experience of the pipeline in industrial and civil buildings in the actual production. For composting, no specific pipeline design basis exists.

In the compost ventilation system, certain air outlet speed still needs to be guaranteed, prevents that the heap body from blockking up the air outlet aperture on the air pipe. Simultaneously, because the orifice air-out direction receives static pressure to produce velocity of flow and intraductal velocity of flow combined action, the orifice direction of effluenting can take place the slope, and gaseous can form the vortex in the compost reactor. When the inclination angle is too large, the area above the small hole is a weak ventilation area or a dead angle.

By combining the factors, when the compost ventilation system is designed, under the condition of ensuring a certain ventilation quantity, the invention is designed to carry out innovative design on the aspects of air inlet temperature, air outlet angle of the small holes on the air pipes and air outlet speed so as to reduce the weak ventilation area and improve the ventilation efficiency.

Disclosure of Invention

In view of this, the present invention provides a uniform ventilation system for a compost reactor, which can control the temperature of the inlet air, the outlet angle of the small holes on the air pipe and the outlet speed, so as to reduce the weak ventilation area and improve the ventilation efficiency.

The uniform ventilation system of the composting reactor mainly comprises a ventilation device, a ventilation control device and a temperature control device, wherein the ventilation device comprises a fan, a ventilation pipeline and an air outlet, the ventilation pipeline is arranged below the composting reactor, and the ventilation pipeline is provided with a ventilation hole; the air outlet is arranged above the composting reactor; the fan is arranged at the inlet of the ventilating duct; the ventilation control device comprises a frequency converter, a flow meter and a first controller, wherein the frequency converter is connected with the fan and the controller, the flow meter is arranged on the ventilation pipeline, the flow meter is connected with the controller, the controller calculates the air flow velocity in the ventilation pipeline according to the ventilation flow measured by the flow meter and controls the frequency converter so as to adjust the air flow velocity in the ventilation pipeline; the temperature control device comprises a thermometer, a heater and a second controller, a probe of the thermometer is installed inside the composting reactor, the thermometer is connected with the second controller, the second controller is connected with the heater, the heater is connected with the fan, and the second controller regulates and controls the heater according to the temperature measured by the thermometer. The first controller and the second controller are the same controller or different controllers.

The invention carries out innovative design on the aspects of air inlet temperature, air outlet angle of the small holes on the air pipes and air outlet speed so as to reduce the weak ventilation area and improve the ventilation efficiency. Wherein, temperature control device realizes the control of air inlet temperature, and ventilation control device carries out the control of air-out speed and total pressure to reach the purpose of control air-out speed and air-out angle.

Furthermore, in order to prevent the compost from blocking the air outlet holes, the air outlet speed of the air outlet holes is more than or equal to 10 m/s; in order to ensure that each air outlet hole is prevented from forming a weak air area, the included angle between the air outlet angle of the air vent and the axis of the air pipe where the air vent is located is larger than or equal to 80 degrees.

Furthermore, in order to achieve the air outlet speed and the air outlet angle, the flow velocity vd of the air flow in the pipeline where the vent hole is located is less than or equal to 1.7m/s, and the flow velocity vj generated by the static pressure difference of the air flow in the pipeline where the vent hole is located is greater than or equal to 9.8 m/s.

Further, the ventilation pipeline can include a main pipe and branch pipes, the main pipe is connected with the ventilation control device, the branch pipes are in a group, one group of branch pipes are respectively connected with the main pipe, and the ventilation holes are formed in the branch pipes. This results in more uniform ventilation.

Further, the ventilation hole is located on the upper half global of branch pipe, the ventilation hole is followed branch pipe axial direction is equipped with one row or multirow.

Further, in order to achieve the air outlet speed and the air outlet angle, the total pressure provided by the fan is greater than or equal to 63.8n Pa, wherein n is the number of the branch pipes.

Furthermore, an arc-shaped bell mouth connection mode is adopted between the branch pipe and the main pipe so as to reduce local resistance.

Furthermore, the thermometer is two, is installed respectively in the air intake department of first branch pipe and last branch pipe, and is located the first of every branch pipe the ventilation hole front end.

Further, in order to reduce local resistance, the diameter ratio of the main pipe to the branch pipe is less than or equal to 2 and greater than 1.

Furthermore, the ventilation device also comprises a closed space, the closed space is arranged below the composting reactor, the closed space is communicated with the composting reactor through a circulation hole, and the ventilation pipeline is arranged in the closed space.

The invention conveys ventilation airflow into the composting reactor through the ventilation pipeline, the ventilation pipeline is provided with small ventilation holes, the airflow enters the pile body through the small ventilation holes, and the ventilation airflow is discharged through the air outlet after exchanging heat and gas with the pile body. In order to ensure that no weak ventilation area exists in the stack body, the direction of the air outlet flow of the small ventilation holes is perpendicular to the axial direction of the pipeline as much as possible; in order to avoid blockage of the small holes by the stacks, the air outlet speed of the small ventilation holes is larger than or equal to a certain numerical value. In the invention, in order to ensure the air outlet speed and angle, the air speed of the air outlet branch pipe is set, so that the total pressure of the selected fan is more than or equal to a certain value (excluding the pressure for overcoming the friction resistance and the local resistance loss). When the invention is implemented, the flow of each branch pipe is monitored by the flow meter, and the air quantity of the fan is adjusted by the frequency converter. The ventilation temperature is regulated and controlled by the temperature control device. The invention can basically meet the requirements of controllable air inlet temperature and no ventilation dead angle in the compost, plays the role of improving the ventilation efficiency and the composting effect, realizes uniform air supply in the composting reactor and prevents the local compost from generating the effect of anaerobic reaction.

Drawings

FIG. 1 is a schematic structural view of a composting and ventilating system according to an embodiment of the invention;

FIG. 2 is a schematic structural diagram of a ventilation control device and a temperature control device according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a manifold according to an embodiment of the present invention;

FIG. 4 is a simulated cloud of the cross-sectional gas flow distribution inside the composting reactor according to an embodiment of the invention;

the reference numbers illustrate:

101 ventilating ducts, 102 chain plates, 103 steel plates, 104 air outlets, 105 fans, 1011 main pipes, 1012 branch pipes and a ventilating hole (small ventilating hole) 10121;

20 ventilation control device, 201 frequency converter, 202 flowmeter, 203 first controller;

301 thermometer, 302 heater, 303 second controller.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the invention can be more clearly understood. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely intended to illustrate the spirit of the technical solution of the present invention.

The invention provides a compost uniform ventilation system, which can control the air inlet temperature according to the anaerobic fermentation condition in a compost body; the system can reach the air outlet speed of more than or equal to 10m/s (empirical value) so as to avoid the stack from blocking the small ventilation holes; the system can ensure that the included angle between the air outlet angle and the axial line of the wind pipe is more than or equal to 80 degrees, so that the interior of the stack body almost has no ventilation dead angle. The system is simple to operate and high in practicability.

In order to achieve the purpose, the invention is realized by the following technical scheme:

as shown in figure 1, a compost uniform ventilation system mainly comprises a ventilation control device, a temperature control device and a ventilation device. The ventilation device may further include a ventilation duct 101, a chain plate 102, a steel plate 103, an air outlet 104, a fan 105 (shown in fig. 2), and the like.

The stack is separated from the ventilation ducts 101 by link plates 102. To reduce the risk of the stack blocking the vent holes in the ventilation ducts 101, the link plates 102 are provided with flow holes through which the air flow enters the stack. The aperture of the small circulation hole is larger than that of the vent hole, the aperture of the small circulation hole is generally 2-8mm, and the aperture of the vent hole is 1-5 mm.

The air outlet 104 is located above the stack. The link plate 102 and the steel plate 103 (no small hole is arranged on the steel plate) which are positioned below the pile body form a closed space (as shown in figure 1) with the bottom of the composting reactor, and the ventilation pipeline 101 is positioned in the closed space, so that airflow is forced to enter the pile body through the small circulation holes on the link plate 102, and flows out through the air outlet 104 above the pile body after carrying out heat exchange and gas exchange with the pile body. The design makes the air current of air inlet fully contact with the heap body, avoids the short circuit of air current.

The ventilation duct 101 may further include a main pipe 1011 and a branch pipe 1012, the main pipe 1011 is connected to a ventilation control device, the branch pipe 1012 is connected to the main pipe 1011 (as shown in fig. 2), in order to reduce local resistance, an arc-shaped bell-mouth connection is formed between the main pipe 1011 and the branch pipe 1012, and a diameter ratio of the main pipe 1011 to the branch pipe 1012 is less than or equal to 2 and greater than 1. The branch pipes are preferably a set of pipes arranged in parallel, preferably all perpendicular to the main pipe.

The air flows in the air pipe, static pressure acts on the pipe wall, a small hole (as shown in figure 3) is formed in the air pipe, and due to the static pressure difference between the inside and the outside of the pipe, the air flows out from the hole. The actual flow rate of the gas stream exiting the orifice is influenced by the static pressure-induced flow rate and the flow rate in the tube. Under the influence of the flow velocity in the pipe, the outlet flow direction of the orifice is deflected, and the actual flow velocity is the synthesis velocity.

The flow rate generated by static pressure is

The included angle between the orifice outflow and the wind pipe axial line is alpha, tan alpha is vj/vd

The actual flow rate of the orifice is

In the formula, Pj is the static pressure of air in the air pipe, Pa; rho is the density of air in the air duct, kg/m³(ii) a Alpha is the angle between the orifice outflow and the wind pipe axis; vj is the flow velocity generated by static pressure difference, m/s; ν d is the flow velocity in the tube, m/s; ν is the actual flow rate of the orifice outflow, m/s.

In order to ensure that no weak ventilation area exists in the pile body, the air outlet flow direction of the small holes is perpendicular to the pipeline as much as possible, and the included angle between the air outlet angle and the axis of the air pipe is more than or equal to 80 degrees; and in order to avoid the blockage of the small holes by the stacks, the air outlet speed of the small holes is more than or equal to 10m/s, and the values are substituted into the speed calculation and angle calculation formulas, so that the flow velocity inside the pipe (vd) is less than or equal to 1.7m/s, and the flow velocity generated by static pressure difference (vj) is more than or equal to 9.8 m/s. The static pressure is also provided by the fan.

And the total pressure that the fan needs to provide:

Pq＝Pj+Pd+Pm+Pc

wherein the dynamic pressure in the tube

Static pressure of pipe wall

In the formula, Pq is the total pressure of the fan, Pa; pd is dynamic pressure, Pa, in the tube; pj is pipe wall static pressure Pa; pm is frictional resistance, Pa; pc is the local resistance, Pa.

Because the friction resistance and the local resistance are influenced by the material of the ventilation system and the structures of the main pipe and the branch pipe, the ventilation system has wide application range of materials, including steel plates, galvanized copper plates, stainless steel and the like; the diameters of the main pipe and the branch pipe of the ventilation system are influenced by the air volume, so that in the ventilation system, the total pressure provided by the fan does not include frictional resistance and local resistance. In actual production, according to air pipe materials and main pipe and branch pipe structures, when the total pressure of the fan is selected, frictional resistance and local resistance are added on the basis of the invention.

The total pressure provided by the fan is more than 63.8n Pa, wherein n is the number of branch pipes.

Of course the inclusion of a main duct and a branch duct is for more uniform ventilation, and the present invention will be described by way of example of such a preferred embodiment, without excluding embodiments where the ventilation duct comprises only a main duct. Only the calculation of the ventilation coefficient of the main duct can be performed with reference to the above-described calculation manner.

The ventilation control device mainly comprises a frequency converter 201, a flow meter 202 and a first controller 203 such as a PLC (see FIG. 2). The explanation is made with an example in which the ventilation duct includes a main duct and a branch duct.

As shown in fig. 3, the flow meter 202 may be installed at the air inlets of the first branch pipe 1012 and the last branch pipe 1012 and located at the front end of the first vent hole (vent hole) 10121. The first vent here refers to the vent closest to the dry pipe. This can be calculated from the average of the measurements of the two flow meters. Of course, the measurement method is not limited thereto. The frequency converter 201 is connected with the fan 105 and a first controller 203(PLC), the flow meter 202 is connected with the PLC, and the speed of the air flow in the air outlet pipe can be calculated according to the reading of the flow meter 202, wherein the calculation formula is as follows. The flow meter 202 feeds the monitored flow back to the PLC, the PLC controls the frequency converter 201, and the frequency converter 201 regulates and controls the fan, so that the speed of the airflow in the branch pipe 1012 can be adjusted.

Flow velocity v in pipe_d＝Q/πr₂

Wherein Q is the branch flow rate monitored by the flowmeter, m³S; r is the radius of the branch pipe, m.

The temperature control device mainly comprises a thermometer 301 (the thermometer comprises a probe), a heater 302 and a second controller 303 such as a PLC (see fig. 2). The probe of the thermometer 301 is installed inside the composting reactor and monitors the temperature of the compost body during composting. The thermometer 301 is connected with a second controller 303(PLC), the PLC is connected with the heater 302, the heater 302 is connected with the fan 105, the PLC obtains the temperature according to the thermometer, the opening and closing and the power of the heater 302 are regulated and controlled, and the heater controls the air outlet temperature of the fan.

The first controller and the second controller in the present invention may be two independent controllers or the same controller.

The invention can control the temperature of the composting ventilation system and ensure that the temperature of the air flow of the inlet air meets the requirements of composting reaction; the invention ensures that the air outlet speed of the vent hole is more than or equal to 10m/s, thereby avoiding the stack from blocking the ventilation system; according to the invention, the included angle between the air flow outlet angle of the vent hole and the axis of the air pipe is more than or equal to 80 degrees, so that no ventilation dead angle exists in the stack body, and the ventilation efficiency is improved.