Sludge heat pump low-temperature drying equipment

Abstract

The invention relates to sludge heat pump low-temperature drying equipment which comprises a low-temperature heat pump, a centrifugal fan, a drying box, N groups of air supply boxes, a heat exchange cabinet and sludge flow guide mechanisms, the N groups of sludge flow guide mechanisms are sequentially and alternately arranged left and right from bottom to top in a hinged mode in the drying box, and the N groups of air supply boxes are installed on the outer side wall of the drying box. According to the sludge heat pump low-temperature drying equipment disclosed by the invention, the sludge flow guide mechanism is utilized, so that the sludge is continuously rolled and can be uniformly heated, and the sludge with dry surface is stripped in the rolling process, so that the drying of the internal wet sludge is facilitated; the inclined sludge guide mechanism is utilized, so that the sludge rolls and falls under the action of self gravity, additional power driving is not needed, and energy is saved; the flowing rule of the hot air is matched with the heat required for drying the sludge, and a complicated temperature regulation and control system is also prevented from being used.

Description

Technical Field

[0001] The present invention relates to the technical field of sludge treatment, and particularly relates to a sludge heat pump low-temperature drying device. Background Art

[0002] A large amount of excess sludge is generated during the sewage treatment process. In recent years, in order to reduce the land occupation of sludge landfill and realize the utilization of sludge resources, a drying device is used to dry the sludge and then transport it to a planting soil processing factory to be processed into planting soil.

[0003] Currently, belt hot air dryers are generally used in the sludge drying industry in China. In the invention patent with the application number 202010828648.3, a multi-stage low-temperature drying device and method for sludge coupling internal and external heat and mass transfer are disclosed. According to the kinetic characteristics of sludge low-temperature drying, the sludge drying process is divided into four stages. The air volume and temperature are reasonably allocated according to the moisture content and drying characteristics of the sludge in different stages. A slow-suction section is added between the first falling-rate drying section and the second falling-rate drying section of the sludge, so that the heat on the surface and inside of the sludge is homogenized during the drying process, and the internal and external moisture migration rates are matched, saving energy and improving the drying efficiency.

[0004] However, such belt hot air dryers have the following problems: 1. The sludge is in a relatively static state on the conveyor belt, resulting in the sludge not being able to be turned over for uniform heating; 2. The conveyor belt needs to keep running, consuming energy; 3. Multi-stage temperature control, and the temperature control system is complex. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above problems existing in the prior art and provide a sludge heat pump low-temperature drying device.

[0006] To achieve the above technical purpose and reach the above technical effect, the present invention is realized through the following technical solutions: A sludge heat pump low-temperature drying device includes a low-temperature heat pump, a centrifugal fan, a drying box, a air supply box, and a heat exchange cabinet. N groups of sludge diversion mechanisms are hinged in the drying box and are arranged alternately left and right in sequence from bottom to top. The sludge diversion mechanism is inclined obliquely downward from its feeding side to its discharging side, and the discharging side of a group of sludge diversion mechanisms faces the feeding side of the sludge diversion mechanism located below it. There are N groups of air supply boxes and they are respectively installed on the outer side walls of the drying box. The air outlet of each group of air supply boxes faces the bottom of a group of sludge diversion mechanisms. An inclined filtering mechanism for filtering dust is installed in the heat exchange cabinet. The filtering mechanism divides the interior of the heat exchange cabinet into an air inlet chamber and a heat exchange chamber. The air inlet chamber is connected to the air extraction interface at the top of the drying box through an air extraction pipeline. The condenser of the low-temperature heat pump is installed in the middle of the heat exchange chamber. The centrifugal fan is installed at the lower part of the heat exchange chamber. The air outlet of the centrifugal fan is connected to the air inlet interface of the air supply box through an air supply diversion pipeline.

[0007] Among them, the sludge diversion mechanism includes a rectangular bottom frame and a rectangular stainless steel mesh. The stainless steel mesh is installed at the upper end of the bottom frame. The feeding side of the bottom frame is hinged to the drying box through a hinge shaft. A tension spring for making the sludge diversion mechanism shake up and down is installed between the discharging side of the bottom frame and the drying box.

[0008] Among them, the inclination angle of the sludge diversion mechanism is 5 - 30°.

[0009] As a preferred method, the inclination angle of the sludge diversion mechanism is 15°.

[0010] Among them, the air supply box includes an air supply box body in the shape of a cuboid box. At least one air distribution plate is installed in the air supply box body. Connecting plates are fixedly connected to the upper and lower ends of the air supply box respectively. The connecting plates are connected to the drying box with screws. Air inlet holes communicating with the opening of the air supply box body are opened on the side wall of the drying box. The opening of the air supply box body faces the bottom of the sludge diversion mechanism. An air inlet interface communicating with the inside of the air supply box body is arranged at one end of the air supply box body far away from the drying box.

[0011] Among them, the upper part of the filtering mechanism inclines towards the direction close to the air extraction pipeline. The inclination angle of the filtering mechanism is 10 - 20°. The filtering mechanism includes a rectangular installation frame and a rectangular dust filter cloth. The dust filter cloth is installed on the side of the installation frame close to the ventilation pipeline.

[0012] Preferably, a drawer chute is arranged at the bottom of the air inlet chamber. A drawer for collecting dust is inserted in the drawer chute.

[0013] Among them, the air supply diversion pipeline includes an air supply main pipe, a vertical diversion main pipe, and air supply branch pipes. N air supply branch pipes arranged alternately left and right in sequence from bottom to top are fixedly connected to the side wall of the diversion main pipe. The diversion main pipe is respectively connected to each air supply branch pipe. The air supply branch pipes incline obliquely upward from the end connected to the diversion main pipe to the end far away from the diversion main pipe. The included angle between the diversion main pipe and the air supply branch pipes is 30 - 45°. A plug is installed at the top of the diversion main pipe. The air supply main pipe is installed between the bottom of the diversion main pipe and the air outlet of the centrifugal fan. The air supply branch pipes are installed between the air supply branch pipes and the air inlet interface of the air supply box.

[0014] Preferably, at one end of each shunt branch pipe fixedly connected to the shunt main pipe, there is a wind intercepting hood extending into the shunt main pipe.

[0015] Furthermore, it further includes a Z-shaped elevator, and the discharge port of the Z-shaped elevator is communicated with the feeding hopper at the top of the drying box.

[0016] The beneficial effects of the present invention are as follows: 1. In the drying box, multiple groups of sludge guiding mechanisms are hinged and arranged alternately left and right in sequence from bottom to top. After the sludge falls onto the top sludge guiding mechanism, it rolls down along the surface of the sludge guiding mechanism under the action of its own gravity, causing the sludge to continuously tumble, enabling uniform heating, and the dried sludge on the surface peels off during the tumbling process, which helps the moist sludge inside to be dried; 2. By using the inclined sludge guiding mechanism, the sludge rolls down under the action of its own gravity, without the need for additional power drive, saving energy; 3. Multiple groups of air supply boxes are installed on the outer side wall of the drying box, and the air outlet of each group of air supply boxes faces the bottom of a group of sludge guiding mechanisms. The air outlet of the centrifugal fan is connected to the air inlet interface of the air supply box through an air supply shunt pipeline. A suction interface is provided at the top of the drying box. Although the hot air blown out from each group of air supply boxes has the same temperature, the hot air flows from bottom to top in the drying box, so that the amount of hot air is more at the position closer to the top of the drying box. And the moist sludge rolls down from top to bottom, and the sludge closer to the top of the drying box requires more heat. Thus, the flow law of the hot air is adapted to the heat required for sludge drying, and the use of a complex temperature control system is also avoided. Description of the Drawings

[0017] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of the sludge heat pump low-temperature drying equipment in the present invention; Figure 2 is a schematic structural diagram of the interior of the drying box in the present invention; Figure 3 is a schematic structural diagram of the sludge guiding mechanism in the present invention; Figure 4 is a schematic structural diagram of the air supply box in the present invention; Figure 5 is a schematic structural diagram of one side of the heat exchange cabinet opened and combined with the low-temperature heat pump in the present invention; Figure 6 is a schematic structural diagram of the air supply shunt pipeline in the present invention; Figure 7 is a schematic structural diagram of the shunt main pipe after longitudinal cutting in the present invention; Description of reference numerals in the figure: drying oven 1, loading hopper 11, exhaust interface 12, sludge outlet 13, sludge diversion mechanism 2, bottom frame 21, stainless steel mesh 22, hinge shaft 23, tension spring 24, air supply box 3, air supply box body 31, air distribution plate 32, connecting plate 33, air inlet interface 34, heat exchange cabinet 4, filtering mechanism 41, air inlet chamber 42, heat exchange chamber 43, drawer 44, low-temperature heat pump 5, condenser 51, centrifugal fan 6, exhaust duct 7, air supply shunt duct 8, air supply main duct 81, shunt main duct 82, air supply branch duct 83, shunt branch duct 84, plug 85, air intercepting hood 86, Z-shaped elevator 9. Detailed implementation manners

[0018] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0019] As Figures 1 to 7 shown, a sludge heat pump low-temperature drying device includes a low-temperature heat pump 5, a centrifugal fan 6, a Z-shaped elevator 9, a drying oven 1, an air supply box 3, and a heat exchange cabinet 4. A funnel-shaped loading hopper 11 and an annular exhaust interface 12 are provided at the top of the drying oven 1, and a funnel-shaped sludge outlet 13 is provided at the bottom of the drying oven 1. The discharge port of the Z-shaped elevator 9 is communicated with the loading hopper 11 at the top of the drying oven 1.

[0020] Eight groups of sludge diversion mechanisms 2 are hinged in the drying oven 1 and are arranged alternately left and right in sequence from bottom to top. The sludge diversion mechanism 2 is inclined obliquely downward from its loading side to its discharging side, and the discharging side of a group of sludge diversion mechanisms 2 faces the loading side of the sludge diversion mechanism 2 located below it.

[0021] The sludge diversion mechanism 2 includes a rectangular bottom frame 21 and a rectangular stainless steel mesh 22. The stainless steel mesh 22 is installed at the upper end of the bottom frame 21. The loading side of the bottom frame 21 is hinged to the drying oven 1 through a hinge shaft 23. A tension spring 24 for jolting the sludge diversion mechanism 2 up and down is installed between the discharging side of the bottom frame 21 and the drying oven 1. When the sludge rolls on the stainless steel mesh 22, the stainless steel mesh 22 jolts up and down under the cooperation of the tension spring 24, which can not only prevent the sludge from getting stuck on the stainless steel mesh 22, but also facilitate the peeling of the surface-dried sludge.

[0022] The inclination angle of the sludge diversion mechanism 2 is 5-30°. In this embodiment, the inclination angle of the sludge diversion mechanism 2 is 15°.

[0023] Multiple groups of sludge diversion mechanisms are hinged in the drying oven and are arranged alternately left and right in sequence from bottom to top. After the sludge falls onto the top sludge diversion mechanism, it rolls down along the surface of the sludge diversion mechanism under the action of its own gravity, causing the sludge to tumble continuously, enabling uniform heating, and the surface-dried sludge peels off during the tumbling process, which helps the internal wet sludge to be dried.

[0024] By using a sludge diversion mechanism arranged obliquely, the sludge rolls and falls under its own gravity without the need for additional power drive, saving energy.

[0025] There are 8 groups of air supply boxes 3, which are respectively installed on the outer side walls of the drying box 1. The air outlet of each group of air supply boxes 3 faces the bottom of a group of sludge diversion mechanisms 2. The air supply box 3 includes an air supply box body 31 in the shape of a cuboid box. At least one air distribution plate 32 is installed in the air supply box body 31. Connecting plates 33 are fixedly connected to the upper and lower ends of the air supply box 3 respectively. The connecting plates 33 are connected to the drying box 1 with screws. An air inlet hole communicating with the opening of the air supply box body 31 is opened on the side wall of the drying box 1. The opening of the air supply box body 31 faces the bottom of the sludge diversion mechanism 2. An air inlet interface 34 communicating with the inside of the air supply box body 31 is arranged at one end of the air supply box body 31 away from the drying box 1.

[0026] An inclined filtering mechanism 41 for filtering dust is installed in the heat exchange cabinet 4. The filtering mechanism 41 divides the inside of the heat exchange cabinet 4 into an air inlet chamber 42 and a heat exchange chamber 43. The air inlet chamber 42 is communicated with the air extraction interface at the top of the drying box 1 through an air extraction pipe 7. The condenser 51 of the low-temperature heat pump 5 is installed in the middle of the heat exchange chamber.

[0027] Specifically, the upper part of the filtering mechanism 41 is inclined towards the direction close to the air extraction pipe 7, and the inclination angle of the filtering mechanism 41 is 10 - 20°; the filtering mechanism 41 includes a rectangular installation frame and a rectangular dust filter cloth. The dust filter cloth 43 is installed on one side of the installation frame 42 close to the ventilation pipe 7.

[0028] A drawer chute is arranged at the bottom of the air inlet chamber 42, and a drawer 44 for collecting dust is inserted into the drawer chute. The dust entering the air inlet chamber is intercepted by the filtering mechanism 41 and falls into the drawer 44 under the action of its own gravity. The staff pour the dust in the drawer 44 into the sludge storage and transportation device every once in a while.

[0029] The centrifugal fan 6 is installed at the lower part of the heat exchange chamber. The air outlet of the centrifugal fan 6 is connected to the air inlet interface of the air supply box 3 through the air supply shunt pipeline 8. The air supply shunt pipeline 8 includes an air supply main pipe 81, a vertical shunt main pipe 82, and air supply branch pipes 83. There are 8 shunt branch pipes 84 fixedly connected to the side wall of the shunt main pipe 82 and arranged alternately left and right from bottom to top in sequence. The shunt main pipe 82 is respectively connected to each shunt branch pipe 84. The shunt branch pipe 84 slopes obliquely upward from the end connected to the shunt main pipe 82 to the end far from the shunt main pipe 82. The included angle between the shunt main pipe 82 and the shunt branch pipe 84 is 30° to 45°. In this embodiment, the included angle between the shunt main pipe 82 and the shunt branch pipe 84 is 30°; a plug 85 is installed at the top of the shunt main pipe 82 to prevent hot air from being discharged from the top of the shunt main pipe 82; the air supply main pipe 81 is installed between the bottom of the shunt main pipe 82 and the air outlet of the centrifugal fan 6, and the air supply branch pipe 83 is installed between the shunt branch pipe 84 and the air inlet interface 34 of the air supply box 3.

[0030] At the end where each shunt branch pipe 84 is fixedly connected to the shunt main pipe 82, there is an air intercepting cover 86 extending into the shunt main pipe 82. The air intercepting cover 86 is used to intercept the hot air in the shunt main pipe 82 into the corresponding shunt branch pipe 84 to ensure that the hot air enters the shunt branch pipe 84.

[0031] A plurality of air supply boxes are installed on the outer side wall of the drying oven, and the air outlets of each group of air supply boxes face the bottom of a group of sludge diversion mechanisms. The air outlet of the centrifugal fan is connected to the air inlet interface of the air supply box through the air supply shunt pipeline. An air extraction interface is arranged at the top of the drying oven. Although the temperature of the hot air blown out from each group of air supply boxes is the same, the hot air flows from bottom to top in the drying oven, so that the amount of hot air is more at the position closer to the top of the drying oven. And the wet sludge rolls down from top to bottom, and the sludge closer to the top of the drying oven requires more heat. Thus, the flow law of the hot air is adapted to the heat required for sludge drying, and a complex temperature control system is also avoided.

[0032] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A sludge heat pump low-temperature drying device, including a low-temperature heat pump and a centrifugal fan, is characterized in that It also includes: A drying oven, in which N groups of sludge diversion mechanisms are hinged and arranged alternately left and right from bottom to top in sequence. The sludge diversion mechanisms are inclined obliquely downward from their feeding sides to their discharging sides. The discharging side of one group of sludge diversion mechanisms faces the feeding side of the sludge diversion mechanism located below it. Air supply boxes, there are N groups of air supply boxes and they are respectively installed on the outer side walls of the drying oven. The air outlet of each group of air supply boxes faces the bottom of one group of sludge diversion mechanisms. A heat exchange cabinet, in which an inclined filtering mechanism for filtering dust is installed. The filtering mechanism divides the interior of the heat exchange cabinet into an air inlet chamber and a heat exchange chamber. The air inlet chamber is connected to the air extraction interface at the top of the drying oven through an air extraction pipe. The condenser of the low-temperature heat pump is installed in the middle of the heat exchange chamber. The centrifugal fan is installed at the lower part of the heat exchange chamber. The air outlet of the centrifugal fan is connected to the air inlet interface of the air supply box through an air supply diversion pipe.

2. The sludge heat pump low-temperature drying equipment according to claim 1, characterized in that: The sludge diversion mechanism includes a rectangular bottom frame and a rectangular stainless steel mesh. The stainless steel mesh is installed at the upper end of the bottom frame. The feeding side of the bottom frame is hinged to the drying oven through a hinge shaft. A tension spring for making the sludge diversion mechanism shake up and down is installed between the discharging side of the bottom frame and the drying oven.

3. The sludge heat pump low-temperature drying equipment according to claim 1, wherein: The inclination angle of the sludge diversion mechanism is 5 - 30°.

4. The sludge heat pump low-temperature drying equipment according to claim 3, characterized in that: The inclination angle of the sludge diversion mechanism is 15°.

5. The sludge heat pump low-temperature drying equipment according to claim 1, wherein: The air supply box includes an air supply box body in the shape of a cuboid box. At least one air distribution plate is installed in the air supply box body. Connecting plates are fixedly connected to the upper and lower ends of the air supply box respectively. The connecting plates are connected to the drying oven with screws. An air inlet hole communicating with the opening of the air supply box body is opened on the side wall of the drying oven. The opening of the air supply box body faces the bottom of the sludge diversion mechanism. An air inlet interface communicating with the inside of the air supply box body is arranged at one end of the air supply box body away from the drying oven.

6. The sludge heat pump low-temperature drying equipment according to claim 1, characterized in that: The upper part of the filtering mechanism is inclined towards the direction close to the air extraction pipe. The inclination angle of the filtering mechanism is 10 - 20°. The filtering mechanism includes a rectangular installation frame and a rectangular dust filter cloth. The dust filter cloth is installed on one side of the installation frame close to the ventilation pipe.

7. The sludge heat pump low-temperature drying equipment according to claim 1, characterized in that: A drawer chute is arranged at the bottom of the air inlet chamber. A drawer for collecting dust is inserted in the drawer chute.

8. The sludge heat pump low-temperature drying equipment according to claim 1, characterized in that: The air supply diversion pipe includes an air supply main pipe, a vertical diversion main pipe, and air supply branch pipes. N diversion branch pipes are fixedly connected to the side wall of the diversion main pipe and are arranged alternately left and right from bottom to top in sequence. The diversion main pipe is respectively connected to each diversion branch pipe. The diversion branch pipes are inclined obliquely upward from the end connected to the diversion main pipe to the end away from the diversion main pipe. The included angle between the diversion main pipe and the diversion branch pipes is 30 - 45°. A plug is installed at the top of the diversion main pipe. The air supply main pipe is installed between the bottom of the diversion main pipe and the air outlet of the centrifugal fan. The air supply branch pipes are installed between the diversion branch pipes and the air inlet interfaces of the air supply boxes.

9. The sludge heat pump low-temperature drying equipment according to claim 8, characterized in that: At the end of each diversion branch pipe connected to the diversion main pipe, a wind intercepting cover extending into the interior of the diversion main pipe is arranged.

10. The sludge heat pump low-temperature drying equipment according to claim 1, characterized in that: It also includes a Z-shaped elevator, and the discharge port of the Z-shaped elevator is connected to the feeding hopper at the top of the drying oven.

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