Sludge drying gasification incineration integrated treatment method

Abstract

The present application relates to a kind of sludge drying gasification incineration integrated processing method, belong to sludge processing technical field, solve the problem of high energy consumption, high processing cost of sludge processing equipment.The present application includes: S1 preheating process: sludge is preheated, and by atomizer is sprayed into spray drying furnace in atomized state;S2 vaporization drying process: spray drying furnace is baked to the mist state sludge in furnace, and sludge is gasified and dried;S3 incineration process: solid after sludge vaporization drying is imported into gasification incinerator and is incinerated;S4 waste heat recovery process: gasification incinerator is connected with waste heat boiler, and then it can be discharged by waste heat boiler after incineration middle ash and flue gas;Gasification incinerator is provided with third heat conducting oil pipe;Sludge preheating pipe and spray drying furnace can be heated by heat conducting oil and heated, and then realize the preheating, drying and gasification of sludge.The present application utilizes heat conducting oil and air preheater to carry out heat recovery, realizes the effective use of energy, reduces energy consumption and saves cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sludge treatment, and particularly relates to a sludge drying, gasification and incineration integrated treatment method. BACKGROUND

[0002] The sludge represented by municipal sewage sludge has a high water content (about 72% after mechanical dewatering), a low calorific value, a low heat output (200-400 kCal / kg), occupies space for landfill treatment, is difficult to maintain in the later period, easily blocks the drainage system, and has a high maintenance cost; at present, a relatively complete treatment method is incineration. The heat value of the sludge after mechanical dewatering is too low to reach the lower limit of the heat value (generally 800-1200 kCal / kg) required for normal combustion of solid fuel, and therefore needs to be dried and dewatered to improve the heat value.

[0003] The existing sludge incineration technology mostly adopts a process of drying first and then incinerating, and the heat source medium for drying is mostly heat-conducting oil or steam; there is also a process of low-temperature drying by using a heat pump, but the drying effect and power consumption are short boards. In the existing sludge treatment system, drying and incineration are generally carried out separately, the total energy consumption of drying and incineration is high, the equipment is complex, the initial investment is high, the operation cost is high, and the current operation cost is often higher than the sludge disposal cost that can be borne or paid, and therefore it is difficult to popularize and apply.

[0004] Therefore, based on the demand for improving energy utilization efficiency and reducing initial investment and operation cost, the present application provides a sludge drying, gasification and incineration integrated treatment method. SUMMARY

[0005] In view of the above analysis, the present application aims to provide a sludge drying, gasification and incineration integrated treatment method to solve the problems of high initial investment and high operation cost of sludge treatment due to the low heat value of sludge. The integrated drying and incineration can effectively reduce the initial investment of equipment; in the whole integrated drying, incineration and heat recovery process, the energy is fully utilized in stages in accordance with the requirements of the second law of thermodynamics, which can effectively reduce the operation cost of sludge incineration.

[0006] The purpose of the present application is mainly realized by the following technical solutions:

[0007] A sludge drying, gasification and incineration integrated treatment method, comprising:

[0008] S1, a preheating process: the sludge is preheated by a sludge pump pipe and then sprayed into a spray drying furnace in an atomized state by a sprayer;

[0009] S2, a vaporization drying process: the spray drying furnace bakes the sludge in a mist state in the furnace to vaporize the water in the sludge and thus realize sludge drying;

[0010] S3 burning process: the solid produced after the sludge gasification drying treatment is introduced into the gasification incinerator 30 for burning; the third heat conducting oil pipe is arranged on the gasification incinerator 30, and the third heat conducting oil pipe is filled with heat conducting oil; the sludge pump pipe 3 and the spray drying furnace 5 can be heated and warmed by the heat conducting oil, thereby realizing the preheating and drying of the sludge;

[0011] S4 waste heat recovery process: the gasification incinerator 30 is connected with the waste heat boiler 34, thereby being capable of discharging the incinerated fly ash and flue gas through the waste heat boiler 34; the waste heat boiler 34 recovers heat through the gas preheater and introduces the preheated air into the spray drying furnace 5 and the gasification incinerator.

[0012] Further, in the S1 preheating process, the outside of the sludge pump pipe is provided with the first heat conducting oil pipe, and the first heat conducting oil pipe is communicated with the third heat conducting oil pipe in the S3 burning process; further, the first heat conducting oil pipe preheats the sludge pump pipe and the sludge inside the sludge pump pipe by the heat conducting oil flowing in the first heat conducting oil pipe.

[0013] Further, in the S2 gasification drying process, the inner wall of the spray drying furnace is provided with the second heat conducting oil pipe communicated with the third heat conducting oil pipe in the S3 burning process; the second heat conducting oil pipe heats and insulates the furnace cavity of the spray drying furnace by the heat conducting oil flowing in the second heat conducting oil pipe.

[0014] Further, in the S2 gasification drying process, the gas (containing water vapor and non-condensable gas) generated by baking the sludge through the spray drying furnace is introduced into the condenser for condensation; after condensation, liquid sewage and gaseous non-condensable gas are produced; wherein the sewage is discharged and purified by biochemical treatment and discharged up to the standard; the non-condensable gas is introduced into the gasification incinerator in the S3 burning process for burning.

[0015] Further, in the S4 waste heat recovery process, the waste heat boiler is nested with the first gas preheater and the second gas preheater, and the first gas preheater and the second gas preheater can heat the gas flowing through the inside thereof by absorbing the flue gas waste heat in the waste heat boiler.

[0016] Further, the non-condensable gas generated in the S2 gasification drying process is first introduced into the first gas preheater in the S4 waste heat recovery process for preheating, and then introduced into the gasification incinerator in the S3 burning process for burning.

[0017] Further, the second gas preheater in the S4 waste heat recovery process introduces air, and the high-temperature flue gas in the waste heat boiler heats the low-temperature air to obtain high-temperature air.

[0018] Further, the high-temperature air obtained in the S4 waste heat recovery process is respectively introduced into a spray drying furnace and a gasification incinerator, and is respectively used for sludge vaporization drying and incineration.

[0019] Further, the bottom of the spray drying furnace is provided with a material guide pipe and a first air inlet pipe; the upper end of the material guide pipe is communicated with the inner cavity of the spray drying furnace, and the lower end is communicated with the auger conveyor, so that the dried sludge is sent into the gasification incinerator for incineration through the auger conveyor.

[0020] Further, the gasification incinerator comprises a gasification incineration chamber and a flue gas furnace channel; the gasification incineration chamber is used for gasification and incineration of combustible dried sludge and non-condensable gas; the flue gas furnace channel is communicated with the waste heat boiler, and the high-temperature flue gas generated by combustion is introduced into the waste heat boiler.

[0021] The technical scheme of the present application can at least achieve one of the following effects:

[0022] 1. The sludge drying, gasification and incineration integrated treatment method of the present application uses the heat generated by incineration to heat the heat transfer oil, the heat transfer oil pipe is arranged in the sludge pump pipe to pressurize and preheat the sludge; in addition, the heat transfer oil pipe is also arranged in the atomization gasification furnace to maintain the temperature in the furnace, thereby improving the drying effect, which is conducive to significantly improving the heat value of the sludge entering the gasification incinerator, so that the subsequent incineration is more complete, and the efficiency of sludge treatment is improved.

[0023] 2. The sludge drying, gasification and incineration integrated treatment method of the present application uses the atomization and blasting method to spray the sludge into the atomization vaporization drying furnace, and uses the heat transfer oil to heat and raise the temperature of the atomization vaporization drying furnace, so that it can quickly dry and dry the sludge in the atomized state sprayed into the furnace, improve the sludge drying efficiency, the drying effect is good, and the water removed after drying is more, which is conducive to reducing the energy consumption of the subsequent incineration process.

[0024] 3. The sludge drying, gasification and incineration integrated treatment method of the present application, the front section of the gasification incinerator is a gasification incineration chamber, the middle section is a flue gas furnace channel, and the rear section is connected with a waste heat boiler; a gas preheater structure is nested and combined with the waste heat boiler, which can heat the air to a certain high temperature (such as 400 degrees Celsius or higher), and then introduce the high-temperature air into the gasification incinerator to improve the incineration temperature, improve the gasification effect of incineration, make up for the low heat value of the sludge (even after drying), further improve the heat value (temperature) of the dried sludge to promote its combustion effect, improve the sludge treatment efficiency, and save costs.

[0025] 4. The sludge drying, gasification and incineration integrated treatment method of the present application adopts a TFB gasification and incineration method, first preheats the sludge by heat transfer oil to promote sludge drying, and then high-temperature burns by the gasification incinerator, realizes low-temperature gasification and high-temperature burnout, can realize double low of CO and NOx, and greatly reduces the flue gas purification cost.

[0026] In the present application, the above technical solutions can be combined with each other to realize more preferred combination solutions. Other features and advantages of the present application will be described in the subsequent specification, and some advantages will become apparent from the specification, or will be understood by implementing the present application. The purposes and other advantages of the present application can be realized and obtained from the contents specifically indicated in the specification and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0027] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0028] Figure 1 A schematic diagram of the principle of the sludge drying gasification incineration integrated treatment method of the present application;

[0029] Figure 2 A schematic diagram of the heat conduction oil circulation principle of the sludge drying gasification incineration integrated treatment method of the present application;

[0030] Figure 3 A schematic diagram of the structure of the spray drying furnace of the sludge drying gasification incineration integrated treatment method of the present application;

[0031] Figure 4 A schematic diagram of the structure of the sludge preheating assembly and the atomizer of the sludge drying gasification incineration integrated treatment method of the present application;

[0032] Figure 5 A cross-sectional view of the atomizer of the sludge drying gasification incineration integrated treatment method of the present application;

[0033] Figure 6 A schematic diagram of the structure of the condenser of the sludge drying gasification incineration integrated treatment method of the present application;

[0034] Figure 7 A schematic diagram of the structure of the gasification incineration furnace and the waste heat boiler of the sludge drying gasification incineration integrated treatment method of the present application;

[0035] Figure 8 A schematic diagram of the preheating pipe arrangement of the air preheater of the present application;

[0036] Figure 9 A schematic diagram of the structure of the preheating pipe of the present application.

[0037] LIST OF REFERENCE NUMERALS:

[0038] 1-feeding groove; 2-feeder; 3-sludge pump pipe; 4-first heat conducting oil pipe; 5-spray drying furnace; 6-sprayer; 601-first high pressure air inlet; 602-second high pressure air inlet; 603-third high pressure air inlet; 7-second heat conducting oil pipe; 8-air outlet pipe; 9-first oil inlet interface; 10-first oil outlet interface; 11-conveying pipe; 12-first air inlet pipe; 13-cage conveyor; 14-driving motor; 15-first electromagnetic valve; 16-first oil pump; 17-air bellow; 18-condensing pipe; 19-condensing pipe air inlet interface; 20-condensing pipe air outlet interface; 21-liquid discharge interface; 22-exchange air pipe; 23-air equalizing plate; 24-air distribution plate; 25-first flue gas chamber; 26-second flue gas chamber; 27-communication chamber; 28-second oil inlet interface; 29-second oil outlet interface; 30-gasification incinerator; 31-second air inlet pipe; 32-water inlet interface; 33-water outlet interface; 34-exhaust heat boiler; 35-first gas preheater; 36-second gas preheater; 37-dust outlet; 38-flue gas outlet. DETAILED DESCRIPTION

[0039] The preferred embodiments of the present application will be described in detail below with reference to the drawings, which constitute a part of this application, and illustrate the principles of the application together with the embodiments thereof, but are not intended to limit the scope of the application.

[0040] Embodiment 1

[0041] In one specific embodiment of the present application, a sludge drying, gasification and incineration integrated treatment method is disclosed, as shown in Figure 1 , Figure 2 , which comprises:

[0042] S1 preheating process: the sludge is preheated by the sludge pump pipe 3 and then sprayed into the spray drying furnace in atomized state by the sprayer 6;

[0043] S2 vaporization and drying process: the spray drying furnace 5 bakes the atomized sludge in the furnace to gasify and dry the sludge;

[0044] S3 incineration process: the solid produced after the sludge vaporization and drying treatment is fed into the gasification incinerator 30 for incineration; the third heat conducting oil pipe is arranged on the gasification incinerator 30, and heat conducting oil is filled in the third heat conducting oil pipe; the sludge pump pipe 3 and the spray drying furnace 5 can be heated and warmed by the heat conducting oil, thereby realizing the preheating, drying and gasification of the sludge;

[0045] S4 exhaust heat recovery process: the gasification incinerator 30 is connected with the exhaust heat boiler 34, thereby being able to discharge the incinerated fly ash and flue gas through the exhaust heat boiler 34; the exhaust heat boiler 34 recovers heat through the gas preheater and preheats air to be fed into the spray drying furnace 5 and the gasification incinerator.

[0046] I, S1 preheating process:

[0047] Specifically, one end of the sludge pump pipe 3 is connected to the feeding tank 1, and the sludge enters the sludge pump pipe 3 through the feeding tank 1; and a feeder 2 is arranged between the sludge pump pipe 3 and the feeding tank 1, and the feeder 2 is used to guide the sludge into the sludge pump pipe 3. Preferably, the feeder 2 is a double-screw feeder.

[0048] In the S1 preheating process, the first heat conduction oil pipe 4 is arranged outside the sludge pump pipe 3, and the first heat conduction oil pipe 4 is communicated with the third heat conduction oil pipe in the S3 incineration process; further, the first heat conduction oil pipe 4 preheats the sludge pump pipe 3 and the sludge inside the sludge pump pipe 3 through the heat conduction oil flowing inside.

[0049] In the S1 preheating process, multiple groups of first heat conduction oil pipes 4 are arranged on the sludge pump pipe 3; the multiple groups of first heat conduction oil pipes 4 are arranged outside the sludge pump pipe 3, and are used to preheat the sludge in the sludge pump pipe 3. The sludge in the sludge pump pipe 3 is heated by the heat conduction oil in the first heat conduction oil pipe 4; the temperature of the heat conduction oil in the first heat conduction oil pipe 4 ranges from 300℃ to 380℃, and the temperature of the sludge in the sludge pump pipe 3 after heating is controlled to be above 110℃.

[0050] Further, multiple temperature sensors are arranged on the first heat conduction oil pipe 4, and the preheating state of the sludge in the sludge pump pipe 3 is judged by taking the average of multiple temperature values measured by the temperature sensors. For example, the temperatures of multiple positions of the first heat conduction oil pipe 4 measured by the multiple temperature sensors are t1, t2, t3,..., respectively, and the heating temperature of the sludge pump pipe 3 is judged by taking the average of the multiple temperature values.

[0051] Further, a first electromagnetic valve 15 and a first oil pump 16 are arranged between the first heat conduction oil pipe 4 and the third heat conduction oil pipe of the waste heat boiler 34, the flow of the heat conduction oil in the first heat conduction oil pipe 4 is adjusted by the first electromagnetic valve 15, and the flow rate of the heat conduction oil is controlled by the first oil pump 16, so as to realize the temperature control of the heat conduction oil.

[0052] Further, a sludge pump is arranged on the sludge pump pipe 3, and is used to control the speed of the sludge entering the spray drying furnace 5.

[0053] II, S2 vaporization drying process:

[0054] In one specific embodiment of the present application, in the S2 vaporization drying process, a sprayer 6 is used to spray the wet sludge in the sludge pump pipe 3 into the spray drying furnace 5.

[0055] Further, in the S2 vaporization drying process, the inner wall of the spray drying furnace 5 is provided with a second heat conducting oil pipe 7 which is in communication with the third heat conducting oil pipe in the S3 incineration process; the second heat conducting oil pipe 7 heats or insulates the cavity of the spray drying furnace 5 by the heat conducting oil flowing inside.

[0056] In one specific embodiment of the present application, as shown in Figure 3 The furnace body of the spray drying furnace 5 is provided with a plurality of groups of second heat conducting oil pipes 7.

[0057] Preferably, as shown in Figure 3 The furnace body of the spray drying furnace 5 is circular or rectangular in structure.

[0058] Further, the inner wall surface of the spray drying furnace 5 is provided with a plurality of groups of second heat conducting oil pipes 7; each group of second heat conducting oil pipes 7 is in communication with the first oil inlet interface 9 and the second oil inlet interface 10 installed on the outer wall surface of the spray drying furnace 5.

[0059] Specifically, the first oil inlet interface 9 is in communication with the third heat conducting oil pipe of the gasification incinerator 30, the heat conducting oil flows between the third heat conducting oil pipe and the second heat conducting oil pipe 7, thereby being able to transfer heat between the spray drying furnace 5 and the gasification incinerator 30, and heat the internal cavity of the spray drying furnace 5. In the present application, by providing the second heat conducting oil pipe 7 and the heat conducting oil inside, the temperature of the air inside the spray drying furnace 5 is raised, and after the sludge is sprayed into the spray drying furnace 5 by the sprayer 6, it can be quickly dried, and most of the water vapor in the sludge is separated, so that the sludge is quickly dried.

[0060] In one specific embodiment of the present application, the second heat conducting oil pipe 7 is arranged in multiple groups in the form of a ring on the spray drying furnace 5, and the multiple groups of second heat conducting oil pipes 7 are parallel to each other.

[0061] In the present embodiment, in the S2 vaporization drying process, the temperature of the heat conducting oil in the second heat conducting oil pipe 7 is 300-380℃.

[0062] Further, in order to regulate the temperature inside the spray drying furnace 5, a second electromagnetic valve and a second oil pump are arranged between the second heat conducting oil pipe 7 and the third heat conducting oil pipe, for controlling the flow rate of the heat conducting oil inside the second heat conducting oil pipe 7. Specifically, the greater the flow rate of the heat conducting oil, the higher the temperature inside the spray drying furnace 5; when the flow rate of the second heat conducting oil pipe 7 is adjusted to the maximum, the flow rate of the heat conducting oil is adjusted by controlling the speed of the oil pump, thereby being able to regulate the temperature inside the spray drying furnace 5.

[0063] In the present application, the PID controller is arranged to adjust the oil pump speed and valve opening in the heat conducting oil circuit, which can control the flow rate of the heat conducting oil, and the oil amount entering the first heat conducting oil pipe 4 and the second heat conducting oil pipe 7, thereby realizing the regulation of the heat conducting oil temperature, the sludge pump channel 3 temperature and the spray drying furnace 5 cavity temperature.

[0064] Further, in order to realize the rapid vaporization and drying of the sludge in the spray drying furnace 5, a first air inlet pipe 12 is communicated at the bottom of the spray drying furnace 5 in the present application, the first air inlet pipe 12 can blow the high-temperature air heated by the waste heat boiler 34 and the second gas heating preheater from the bottom of the spray drying furnace 5, thereby drying the sludge by the high-temperature air.

[0065] In the present application, the first air inlet pipe 12 blows the high-temperature air in the form of bottom blowing, and the temperature of the high-temperature air in the first air inlet pipe 12 is not less than 400 DEG C in the S2 vaporization and drying process. The present application dries the sludge after atomization by blowing the high-temperature air from the bottom, which can prevent the atomization and drying sludge debris from depositing at the bottom of the spray drying furnace 5, promote the up-and-down circulation of the sludge debris after spraying in the spray drying furnace 5, prolong the residence time of the sludge debris in the spray drying furnace 5, thereby promoting the drying effect, maximizing the drying of more water vapor in the sludge, improving the sludge heat value, and making the sludge have a higher temperature before entering the gasification incinerator 30.

[0066] Further, in order to realize the monitoring of the internal temperature of the spray drying furnace 5, a plurality of temperature sensors are installed on the furnace wall of the spray drying furnace 5 for monitoring the temperature inside the cavity of the spray drying furnace 5.

[0067] Preferably, as shown in the first air inlet pipe 12 and the air outlet pipe 8 are respectively provided with a temperature sensor; four temperature sensors are arranged on the furnace body of the spray drying furnace 5; the temperatures monitored by the plurality of temperature sensors from bottom to top are T0, T1, T2, T3, T4 and T5; the average value of the weighted five temperature values is obtained, that is, the parameter T representing the temperature of the spray drying furnace 5. Figure 3

[0068] Exemplarily, according to the correlation between the temperature at different positions and the temperature inside the furnace cavity, the weighted value adopts a value between 0.8 and 1.2.

[0069] Specifically, the amount of sludge spraying in the spray drying furnace 5 (sludge pump speed) is related to the entire temperature distribution of T1-T5, and the weighted T1, T2, T3, T4 and T5 (average value) is used for the air volume adjustment of the bottom first air inlet pipe 12, and when the air volume is maximum, the speed of the sludge pump is adjusted in turn.

[0070] ​In one specific embodiment of the present application, the bottom of the spray drying furnace 5 is provided with a material guide pipe 11; the upper end of the material guide pipe 11 is communicated with the inner cavity of the spray drying furnace 5, and the lower end is communicated to the auger conveyor 13, and then the dried sludge is sent into the gasification incinerator 30 through the auger conveyor 13 for incineration.

[0071] Specifically, in the S2 vaporization drying process, the lower end of the spray drying furnace 5 is communicated with the material guide pipe 11, the upper end of the material guide pipe 11 is communicated with the inner cavity of the spray drying furnace 5, and the lower end is communicated to the auger conveyor 13. The material guide pipe 11 is used to guide the vaporized and dried sludge into the auger conveyor 13; and then the auger conveyor is driven to rotate by the driving motor 14, so that the dried sludge is conveyed to the gasification incinerator 30 for incineration.

[0072] Further, the pressure of the high-temperature air in the first air inlet pipe 12 is Po, the gas pressure of the spray drying furnace 5 is lower than that of the first air inlet pipe 12, and the pressure value in the cavity of the spray drying furnace 5 is Ped; the difference ΔP between Po and Ped is used as a variable for controlling the conveying amount of the bottom auger conveyor 13, ΔP = Po-Ped, and in actual application, the upper limit and lower limit ΔPmax and ΔPmin of ΔP are given. In implementation, ΔPmax and ΔPmin are calibrated on site, the material guide flow rate of the material guide pipe 11 is controlled, ΔP is controlled to be between ΔPmax and ΔPmin, when the pressure difference is too large, the speed of the auger conveyor 13 is reduced; when the pressure difference is too low, the conveying efficiency of the auger conveyor 13 is increased.

[0073] Specifically, in the S2 vaporization drying process, the gas generated by the drying of the sludge is discharged from the air outlet pipe 8 arranged at the upper end of the spray drying furnace 5; by controlling the flow of the second heat conduction oil pipe 7 on the spray drying furnace 5, the temperature of the gas discharged from the air outlet pipe 8 is controlled to be greater than 100℃; preferably, the temperature of the gas discharged from the air outlet pipe 8 is 120℃±5°.

[0074] Further, the second electromagnetic valve and the second oil pump are arranged between the second heat conduction oil pipe 7 and the third heat conduction oil pipe. In the present application, the oil amount in the first heat conduction oil pipe 4 and the second heat conduction oil pipe 7 is controlled by the PID controller, specifically, the PID controller controls the flow of the first electromagnetic valve and the second electromagnetic valve, and the rotating speed of the first oil pump 16 and the second oil pump, to realize the oil amount and temperature control of the first heat conduction oil pipe 4 and the second heat conduction oil pipe 7.

[0075] Further, in the S2 vaporization drying process, the gas generated by baking the sludge through the spray drying furnace 5 is introduced into the condenser for condensation; after condensation, liquid sewage and gaseous non-condensable gas are generated; wherein the sewage is discharged and purified by biochemical treatment; the non-condensable gas is introduced into the gasification incinerator 30 in the S3 incineration process for incineration.

[0076] Considering that the non-condensable gas discharged from the condenser has a low temperature (low enthalpy), directly introducing it into the gasification incinerator 30 would lower the furnace temperature and increase the combustion energy consumption of the gasification incinerator 30. Therefore, in this invention, the non-condensable gas is heat-exchanged through the waste heat boiler 34 to absorb heat from the combustion flue gas and increase its enthalpy before being introduced into the gasification incinerator 30 for combustion.

[0077] III. S3 Incineration Process:

[0078] like Figure 7 As shown, the gasification incinerator 30 includes a gasification incineration chamber and a flue gas duct; the gasification incineration chamber is used to incinerate combustible dried sludge and non-condensable gas; the flue gas duct is connected to the waste heat boiler 34, and the high-temperature flue gas generated by combustion is introduced into the waste heat boiler 34.

[0079] Specifically, the gasification incineration chamber is used to incinerate dried sludge, and its internal incineration temperature reaches 900°C.

[0080] like Figure 7 As shown, the flue gas duct is an inverted U-shaped structure used to exhaust the flue gas after sludge incineration. A dust outlet is located at the lower end of the flue gas duct to remove the intermediate ash from the sludge incineration. A separator is installed on the side of the flue gas duct, connected to the side of the duct, and a dust outlet is located at the bottom of the separator to remove the intermediate ash.

[0081] Specifically, the flue gas duct includes: a first flue gas duct 25, a second flue gas duct 26, and a connecting duct 27; wherein, the lower end of the first flue gas duct 25 is connected to the gasification and combustion chamber and is arranged parallel to the second flue gas duct 26; the upper end of the first flue gas duct 25 is connected to the upper end of the second flue gas duct 26 through the connecting duct 27.

[0082] In this invention, the sludge is gasified in the gasification incineration chamber of the gasification incinerator 30 to produce gasified gas, which is then burned in the gasification incineration chamber; the gasified gas is also burned in the first flue gas duct 25.

[0083] Furthermore, a third heat transfer oil pipe is installed on the wall of the first flue gas furnace duct 25. The third heat transfer oil pipe recovers the heat generated by the gasification incinerator 30 through the heat transfer oil, and then passes the heat transfer oil into the first heat transfer oil pipe 4 and the second heat transfer oil pipe 7 to preheat and dry the sludge.

[0084] The third heat transfer oil pipe is provided with a second oil inlet 28 and a second oil outlet 29. The second oil inlet 28 is used to introduce heat transfer oil that flows back from the first heat transfer oil pipe 4 and the second heat transfer oil pipe 7 into the third heat transfer oil pipe. The second oil outlet 29 is used to supply heat transfer oil heated by the gasification incinerator 30 to the first heat transfer oil pipe 4 and the second heat transfer oil pipe 7.

[0085] Further, the heat conducting oil in the third heat conducting oil pipe is divided into three routes after being heated by the gasification incinerator 30: one route is supplied to the first heat conducting oil pipe 4 in the S1 preheating process for preheating the sludge; one route is supplied to the second heat conducting oil pipe 7 in the S2 gasification and drying process for gasifying and drying the sprayed sludge; and one route is supplied to the air cooler for cooling, and the flow of the heat conducting oil supplied to the air cooler is adjusted by the valve, thereby controlling the temperature of the heat conducting oil.

[0086] Preferably, the temperature of the heat conducting oil in the first heat conducting oil pipe 4 and the second heat conducting oil pipe 7 is controlled to be 300-380℃.

[0087] Further, the end of the second flue gas furnace 26 is provided with a cooling liquid circulation loop; the cooling liquid circulation loop comprises a liquid cooling pipe, a water inlet interface 32 and a water outlet interface 33; the liquid cooling pipe is wound and arranged on the outer wall of the end of the second flue gas furnace 26, and the two ends are respectively connected to the water inlet interface 32 and the water outlet interface 33; a water tank and a water pump are connected between the water inlet interface 32 and the water outlet interface 33, for introducing cooling liquid into the liquid cooling pipe, thereby cooling the second flue gas furnace 26, and the flue gas in the second flue gas furnace 26 is discharged in the form of medium ash after being cooled.

[0088] IV, S4 waste heat recovery process:

[0089] Further, a waste heat boiler 34 is connected to the upper end of the flue gas furnace or the upper end of the separator, and the high-temperature flue gas generated by incineration enters the waste heat boiler 34. Preferably, the temperature of the high-temperature flue gas in the waste heat boiler 34 is 550℃±10°.

[0090] In one specific embodiment of the present application, as shown in Figure 7 the waste heat boiler 34 is in an inverted U-shaped structure, one end is connected to the flue gas furnace, and the other end is provided with a dust outlet 37 and a flue gas outlet 38.

[0091] In the S4 waste heat recovery process, the waste heat boiler 34 is nested with a first gas preheater 35 and a second gas preheater 36, and the first gas preheater 35 and the second gas preheater 36 can heat the gas flowing through them by absorbing the waste heat of the flue gas in the waste heat boiler 34.

[0092] Further, the first gas preheater 35 is used for preheating the non-condensable gas discharged from the condenser; and the second gas preheater 36 is used for preheating air.

[0093] As shown in Figure 1As shown, the non-condensable gas after condensation in the condenser 18 is firstly introduced into the first gas preheater 35 in the S4 waste heat recovery process for preheating, and then introduced into the gasification incinerator 30 in the S3 incineration process for combustion. Preferably, the temperature of the non-condensable gas after preheating by the first gas preheater 35 reaches at least 200 DEG C.

[0094] As shown in Figure 1 , Figure 7 , the second gas preheater 36 in the S4 waste heat recovery process is introduced into the air, and the low-temperature air is heated by the high-temperature flue gas in the waste heat boiler 34 to obtain high-temperature air. Further, the high-temperature air obtained in the S4 waste heat recovery process is introduced into the spray drying furnace 5 of the S2 vaporization drying process and the gasification incinerator 30 of the S3 incineration process, respectively, thereby realizing the vaporization drying and incineration of the sludge.

[0095] Specifically, the second gas preheater 36 preheats the air to not less than 400 DEG C; the high-temperature air of not less than 400 DEG C is divided into two paths, one path is introduced into the furnace cavity through the first air inlet pipe 12 at the bottom of the spray drying furnace 5 to dry the sludge, and the other path is introduced into the gasification incineration chamber through the second air inlet pipe 31 at the bottom of the gasification incinerator 30 to incinerate the dried sludge.

[0096] In the present application, the gas outlet of the second gas preheater 36 is arranged upstream of the first gas preheater 35. The temperature of the gas after preheating by the second gas preheater 36 is higher than that of the first gas preheater 35.

[0097] Specifically, the first gas preheater 35 and the second gas preheater 36 have the same principle.

[0098] The structure and principle of the gas preheater will be described below Figure 7 .

[0099] Exemplarily, the second gas preheater 36 comprises: a plurality of box bodies 361 and a communication air duct 362; wherein the box bodies 361 are arranged outside the waste heat boiler 34; the communication air duct 362 is used for communicating the plurality of box bodies 361, and when the air flows through the plurality of box bodies 361 in sequence, the air can exchange heat with the waste heat boiler 34 and the high-temperature flue gas inside the waste heat boiler 34.

[0100] Exemplarily, the second gas preheater 36 comprises: preheating pipes 363 and communication air ducts 362; specifically, the preheating pipes 363 are arranged through the inside of the waste heat boiler 34, and the two ends thereof are communicated to the communication air ducts 362 / air inlet ducts / air outlet ducts. In use, the preheating pipes 363 are directly contacted with the high-temperature flue gas inside the waste heat boiler 34, thereby realizing the heating of the gas flowing in the preheating pipes 363. Specifically, the preheating pipes 363 are arranged in multiple groups, and the two groups of preheating pipes 363 are connected through the communication air duct 362. Preferably, the multiple preheating pipes 363 in the same group are arranged in multiple rows and multiple columns inside the waste heat boiler 34, and the two adjacent rows of preheating pipes 363 are arranged in a staggered manner in the flue gas flowing direction, as shown in Figure 8 .

[0101] Preferably, in the embodiment, the preheating pipes 363 are arranged as tapered pipes; as shown in Figure 9 , the preheating pipes 363 are rectangular pipes, and at least one spherical expansion cavity is arranged in the middle part thereof; the gas flows in the preheating pipes 363, and when flowing through the spherical expansion cavity of the preheating pipe 363, a vortex phenomenon is generated, which promotes the heat exchange between the gas and the pipe wall of the preheating pipe 363, thereby improving the heat exchange efficiency and realizing that the gas reaches the expected temperature after flowing through the gas preheater.

[0102] In the present application, the preheating pipes 363 arranged inside are used for heat exchange with the high-temperature flue gas (550℃), so as to improve the preheating effect and the preheating efficiency of the air, so that the low-temperature air can reach the expected temperature (400℃) in a short time, so as to supply sufficient oxygen for the combustion of the gasification incineration chamber and to supply sufficient high-temperature air for the drying of the sludge in the spray drying furnace 5, thereby improving the treatment efficiency and the treatment quality of the sludge.

[0103] In one specific embodiment of the present application, as shown in Figure 7 , the second gas preheater 36 is provided with four box bodies 361, and the four box bodies 361 are communicated through the communication air ducts 362. Among them, three groups are arranged from bottom to top in the tail section (low-temperature section) of the U-shaped waste heat boiler 34, and the lowermost one of the box bodies 361 is connected to the air inlet duct, and one box body 361 is arranged in the front section (high-temperature section) of the waste heat boiler 34, and the box body 361 in the front section of the waste heat boiler 34 is connected to the air outlet duct. Specifically, the front section and the tail section of the waste heat boiler 34 are divided according to the flowing sequence of the high-temperature flue gas inside the waste heat boiler 34.

[0104] Alternatively, as shown in Figure 7 , the second gas preheater 36 is provided with four groups of preheating pipes 363, and the four groups of preheating pipes 363 are communicated through the communication air ducts 362. Among them, three groups of preheating pipes 363 are arranged from bottom to top in the tail section (low-temperature section) of the U-shaped waste heat boiler 34, and one group of preheating pipes 363 is arranged in the head section (high-temperature section) of the waste heat boiler 34. Moreover, the lowermost one of the preheating pipes 363 in the tail section is connected to the air inlet duct, and the preheating pipes 363 in the head section are connected to the air outlet duct.

[0105] In use, air flows through the three boxes 631 / three groups of preheating pipes 363 of the tail section of the waste heat boiler 34 in sequence, and then enters the box 361 / preheating pipe 363 of the head section, so as to realize the step-by-step preheating of air, gradually increase the air temperature, and achieve the optimal preheating effect.

[0106] Correspondingly, the first gas preheater 35 for preheating the non-condensable gas is arranged in the middle section of the waste heat boiler 34, as shown in Figure 7 .

[0107] Further, by controlling the length of the flow path and the flow speed of the non-condensable gas / air in the first gas preheater 35 / second gas preheater 36, the temperature of the non-condensable gas / air after preheating in the first gas preheater 35 / second gas preheater 36 is controlled. In the present application, the temperature of the non-condensable gas after preheating is not lower than 200 DEG C, and the temperature of the air after preheating is not lower than 400 DEG C.

[0108] Compared with the prior art, the technical scheme provided by the present embodiment has at least one of the following beneficial effects:

[0109] 1. In the present embodiment, the preheated sludge is sprayed and exploded in the cavity formed by the second heat-conducting oil pipe 7 (300 DEG C) inside the spray drying furnace 5, and then is sent to the hot air (400 DEG C) at the bottom of the spray drying furnace 5 for ventilation drying. After drying, the moisture content of the sludge is reduced from 72% to 60% or even lower, and after entering the TFB gasification incinerator, the sludge is first gasified and then incinerated.

[0110] 2. The sludge incineration equipment of the present application realizes a solution with high energy efficiency and low operating cost; the direct operating cost can be as low as 150 yuan / t, while the operating cost of the prior art is generally 350-400 yuan / t, and the present application is 200-250 yuan / t lower than the prior art.

[0111] 3. The related equipment of the present application has a simple structure and is easy to manufacture, and the initial investment can be significantly reduced; after the treatment method of the present application is practiced, it is shown that the initial investment of the technical equipment of the present application is about 200,000 yuan / t / d, and the initial investment of the prior art is generally 350-400 yuan / t / d.

[0112] 4. In the present application, the drying and incineration integrated system is arranged according to the principle of heat cascade utilization and the principle of minimum auxiliary fuel, the heat utilization rate is high, the energy consumption for sludge treatment is greatly reduced, and the comprehensive treatment cost is reduced.

[0113] Embodiment 2

[0114] In one specific embodiment of the present application, a specific structure of the sprayer 6 in embodiment 1 is provided.

[0115] As Figure 3、 Figure 4 The sprayer 6 in the present application is a conical structure.

[0116] Specifically, the upper end of the sprayer 6 is connected to the lower end of the sludge pump pipe 3. The lower end of the sprayer 6 has a conical horn, and the horn is in communication with the sludge pump pipe 3 through the connecting pipe at the upper end of the sprayer 6.

[0117] As shown in Figure 4 、 Figure 5 The upper end of the sprayer 6 is connected to the first high-pressure air inlet 601 and the second high-pressure air inlet 602; specifically, the first high-pressure air inlet 601 and the second high-pressure air inlet 602 are in communication with the connecting pipe at the upper end of the sprayer 6, and are symmetrically arranged on both sides of the connecting pipe.

[0118] Further, as shown in Figure 4 、 Figure 5 The conical horn at the lower end of the sprayer 6 is provided with a plurality of third high-pressure air inlets 603 outside the horn.

[0119] Specifically, the plurality of third high-pressure air inlets 603 are arranged in an equidistant array in the circumferential direction outside the horn of the sprayer 6, and the plurality of third high-pressure air inlets 603 are located at the same height, as shown in Figure 5 .

[0120] Preferably, the number of third high-pressure air inlets is 6.

[0121] As shown in Figure 5 The angle between the blowing direction of the plurality of third high-pressure air inlets 603 and the radial direction of the sprayer 6 is α; 10°≤α≤30°; the diameter of the inscribed circle of the blowing direction of the plurality of third high-pressure air inlets 603 is d in .

[0122] Specifically, the blowing direction of the third high-pressure air inlet 603 is inclined downward; as shown in Figure 4 The third high-pressure air inlet 603 is arranged at an angle with the horizontal direction; the angle between the blowing direction of the third high-pressure air inlet 603 and the horizontal direction is 20°-30°.

[0123] Preferably, the cone angle of the internal cavity of the horn of the sprayer 6 is 60°.

[0124] Specifically, the internal flow channel diameter of the connecting pipe at the upper end of the sprayer 6 is D0; the pipe opening diameters of the first high-pressure air inlet 601 and the second high-pressure air inlet 602 are the same, both being 2D0; the height H of the horn of the sprayer 6 is (5-7)D0; the outer diameter D of the position of the third high-pressure air inlet 603 of the horn is (4-6)D0, the internal cavity diameter D1 is (3-4)D0, and D1<D.

[0125] Specifically, the cross section of the sprayer 6 at the height of the third high-pressure air inlet 603 is a circular ring, and the inner diameter of the circular ring is D1; the diameter of the inscribed circle of the blowing direction of the third high-pressure air inlet 603 is d in ; and the inner diameter of the inner cavity of the sprayer 6 is greater than the diameter of the inscribed circle of the blowing direction of the plurality of third high-pressure air inlets 631, that is, D 1> d in . Preferably, d in = 1 / 4D = (1-1.5)D0.

[0126] In the present application, high-pressure air is introduced into the first high-pressure air inlet 601 and the second high-pressure air inlet 602, and high-pressure air is introduced into the upper end of the atomizer 6 to create a high-pressure environment inside the inner conical space of the atomizer 6, thereby promoting the atomization and spraying of the sludge.

[0127] In the present application, by providing a plurality of third high-pressure air inlets 603, high-pressure air is sprayed into the interior of the horn mouth of the sprayer 6, and the high-pressure air is distributed circumferentially, which can pressurize and vortex the sludge inside the horn mouth. That is, the multiple jets of high-pressure air blown in by the third high-pressure air inlets 603 can form a high-speed vortex airflow in the circumferential direction of the sludge, thereby promoting the decomposition and atomization of the sludge, and the decomposed and atomized sludge particles have a certain speed, so that they are sprayed into the inner cavity of the spray drying furnace 5.

[0128] Embodiment 3

[0129] In one specific embodiment of the present application, a specific structure of the condenser in Embodiment 1 is provided.

[0130] In one specific embodiment of the present application, the structure of the condenser is as shown in Figure 6 .

[0131] As shown in Figure 6 , the condenser comprises: a bellows 17, a condensing pipe 18, a condensing pipe air inlet 19, a condensing pipe air outlet 20, a liquid discharge interface 21, and a heat exchange air pipe 22.

[0132] Specifically, the condensing pipe 18 is a tapered pipe or a trapezoidal pipe with gradually increasing dimensions.

[0133] Specifically, one end of the condensing pipe 18 is provided with the condensing pipe air inlet 19, and the other end is provided with the condensing pipe air outlet 20. The exhaust gas discharged from the spray drying furnace 5 enters the condensing pipe 18 through the condensing pipe air inlet 19 and is discharged through the condensing pipe air outlet 20. Preferably, the condensing pipe air outlet 20 opens upward.

[0134] Specifically, the liquid discharge interface 21 is arranged below the condensing pipe 18 and at one end close to the condensing pipe air outlet 20.

[0135] Specifically, the side of the condensing pipe 18 is provided with the air bellow 17 which is fixedly connected with the condensing pipe 18 but not communicated. The inside of the condensing pipe 18 is embeddedly installed with a plurality of heat exchange air pipes 22 which are arranged perpendicularly to the condensing pipe 18 and penetrate through the condensing pipe 18; one end of the heat exchange air pipe 22 is communicated with the air bellow 17 and the other end is communicated with the outside space; preferably, the plurality of heat exchange air pipes 22 are equidistantly arranged along the axial direction of the condensing pipe 18.

[0136] Further, the air pump is installed at the air inlet of the air bellow 17 and can guide the cold air into the air bellow 17 through the air pump.

[0137] In the implementation, the cold air is guided into the air bellow 17 through the air pump, enters the heat exchange air pipe 22 through the air bellow 17, and then exchanges heat with the gas flowing in the condensing pipe 18 through the heat exchange air pipe 22 to condense the gas discharged by the spray drying furnace 5; the liquid generated after condensation is discharged through the liquid discharge interface 21; the non-condensed gas (combustible gas in the sludge) which does not change state after condensation is introduced into the gasification incinerator 30 for incineration.

[0138] Further, in order to improve the condensing effect of the condenser, the air distribution plate 24 is arranged in the air bellow 17 and the air distribution plate 23 is arranged in the condensing pipe 18.

[0139] Specifically, the air distribution plate 24 is arranged parallel to the condensing pipe 18 and is located below the plurality of heat exchange air pipes 22; the surface of the air distribution plate 24 is provided with uneven air holes, so as to be able to adjust the air volume in the heat exchange air pipe 22 through the air distribution plate 24, realize the step arrangement of the cold air, and improve the condensing effect.

[0140] Preferably, the size of the air holes on the air distribution plate 24 gradually decreases from the condensing pipe air inlet interface 19 to the condensing pipe air outlet interface 20. Thus, the air volume flowing into the plurality of heat exchange air pipes 22 is stepwise reduced, the air volume on the side close to the condensing pipe air inlet interface 19 is large, can quickly exchange heat with the gas discharged by the spray drying furnace 5, and then quickly cool the gas; the temperature of the gas is gradually reduced after sequentially exchanging heat with the plurality of heat exchange air pipes 22, and the air volume in the heat exchange air pipe 22 is gradually reduced in cooperation with the step heat exchange of the gas temperature in the condensing pipe 18; the present application can reduce the air volume of the cold air and reduce the equipment power on the premise of realizing the quick condensation of the gas, thereby saving the sludge treatment cost.

[0141] Specifically, as shown in Figure 6 the air distribution plate 23 is arranged in the inside of the condensing pipe 18 and the surface is provided with uniformly distributed air holes; the gas in the condensing pipe 18 is condensed through the heat exchange air pipe 22, is homogenized through the air distribution plate 23, and is discharged through the condensing pipe air outlet interface 20.

[0142] In the implementation, the high-temperature gas discharged from the air outlet pipe 8 of the spray drying furnace 5 is condensed by the condenser, and the temperature of the gas is reduced. Part of the steam is liquefied as liquid and discharged as sewage. The dissolved chemicals in the sewage are purified by biochemical treatment. After condensation, the non-condensed gas is introduced into the gasification incinerator 30 for incineration.

[0143] In the embodiment, the high-temperature gas is heat-exchanged by the multiple heat-exchange air pipes 22, and the flow of the cold air in the multiple heat-exchange air pipes 22 is adjusted by the air distribution plate 24, so as to realize step-by-step heat exchange. With the step-by-step reduction of the temperature of the gas, the amount of the cold air introduced is reduced, so as to avoid excessive consumption of the cold air, reduce the power of the fan and / or the refrigeration equipment, reduce the energy consumption, and reduce the processing cost.

[0144] It is worth noting that: in the present application, "high temperature" and "low temperature" represent the change of the temperature of the gas / conductive oil before and after heating, or before and after heat exchange, which is used to distinguish the endothermic or exothermic state of the substance, and does not represent the specific temperature range.

[0145] The above is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application.

Claims

1. A sludge drying, gasification and incineration integrated treatment method, characterized by, The application relates to a sludge drying and incinerating device. S1 preheating process: sludge is preheated by a sludge pump pipe (3) and sprayed into a spray drying furnace in atomized state by a sprayer (6); S2 vaporization and drying process: the spray drying furnace (5) is used for baking the atomized sludge in the furnace to vaporize and dry the sludge; S3 incinerating process: the solid sludge after vaporization and drying is introduced into a gasification incinerator (30) to be incinerated; the third heat conducting oil pipe is arranged on the gasification incinerator (30) and filled with heat conducting oil; the sludge pump pipe (3) and the spray drying furnace (5) can be heated by the heat conducting oil to realize preheating, drying and vaporization of the sludge; S4 waste heat recovery process: the gasification incinerator (30) is connected with a waste heat boiler (34) to discharge the incinerated medium ash and flue gas through the waste heat boiler (34); the waste heat boiler (34) recovers heat through a gas preheater and preheats air to be introduced into the spray drying furnace (5) and the gasification incinerator; The lower end of the sprayer (6) has a conical nozzle, and the nozzle is communicated with the sludge pump pipe (3) through a connecting pipe at the upper end of the sprayer (6); a plurality of third high-pressure air inlets (603) are arranged outside the conical nozzle; the cross section of the sprayer (6) at the height of the third high-pressure air inlets (603) is a circular ring, and the inner diameter of the circular ring is D1; the diameter of the inscribed circle in the blowing direction of the third high-pressure air inlets (603) is d in ; and the inner diameter of the cavity of the sprayer (6) is greater than the diameter of the inscribed circle in the blowing direction of the third high-pressure air inlets (603), i.e. D1>d in . In the S1 preheating process, the first heat conducting oil pipe (4) is arranged outside the sludge pump pipe (3) and communicated with the third heat conducting oil pipe in the S3 incinerating process; then, the first heat conducting oil pipe (4) preheats the sludge pump pipe (3) and the sludge in the pipe through the heat conducting oil flowing in the pipe; In the S2 vaporization and drying process, the second heat conducting oil pipe (7) is arranged on the inner wall of the spray drying furnace (5) and communicated with the third heat conducting oil pipe in the S3 incinerating process; the second heat conducting oil pipe (7) heats and insulates the furnace cavity of the spray drying furnace (5) through the heat conducting oil flowing in the pipe; the gas generated by baking the sludge in the spray drying furnace (5) is introduced into a condenser to be condensed; the condensed liquid sewage and the non-condensed gas are generated; the sewage is discharged and purified through biochemical treatment; the non-condensed gas is introduced into the gasification incinerator (30) in the S3 incinerating process to be incinerated; In the S4 waste heat recovery process, the first gas preheater (35) and the second gas preheater (36) are arranged on the waste heat boiler (34) and can heat the gas flowing through the inside of the first gas preheater (35) and the second gas preheater (36) by absorbing the flue gas waste heat in the waste heat boiler (34); The non-condensed gas generated in the S2 vaporization and drying process is first introduced into the first gas preheater (35) in the S4 waste heat recovery process to be preheated and then introduced into the gasification incinerator (30) in the S3 incinerating process to be combusted; the air is introduced into the second gas preheater (36) in the S4 waste heat recovery process to be heated by the high-temperature flue gas in the waste heat boiler (34) to obtain high-temperature air; the high-temperature air obtained in the S4 waste heat recovery process is introduced into the spray drying furnace (5) and the gasification incinerator (30) to vaporize, dry and incinerate the sludge.

2. The sludge drying gasification incineration integrated treatment method according to claim 1, characterized by, The bottom of the spray drying furnace (5) is provided with a material guide pipe (11) and a first air inlet pipe (12); the upper end of the material guide pipe (11) is communicated with the inner cavity of the spray drying furnace (5), and the lower end is communicated to the auger conveyor (13), and then the dried sludge is sent into the gasification incinerator (30) through the auger conveyor (13) for incineration.

3. The sludge drying gasification incineration integrated treatment method according to claim 2, characterized by, The gasification incinerator (30) comprises a gasification incineration chamber and a flue gas channel; the gasification incineration chamber is used for gasifying and incinerating combustible dried sludge and non-condensable gas; the flue gas channel is communicated with a waste heat boiler (34), and high-temperature flue gas generated by combustion is introduced into the waste heat boiler (34).

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