CN102746904A - Waste gas treatment device and treatment process in waste rubber and plastic pyrolysis - Google Patents

Abstract

The invention discloses a waste gas treatment device and a waste gas treatment process in waste rubber and plastic cracking, and belongs to the field of environmental protection. The device comprises a buffer tank, a liquid separating tank, a purifying tank, a desulfurizing tank, a safety tank, a vacuum pump, a corrosion-resistant pump, second to eighth stop valves, a ball valve, a gate valve, first to fifth blowoff valves, a steam valve, a gas respirator and an explosion-proof device. The embodiment of the invention can effectively treat solid dust, floating oil fume, sulfur dioxide and harmful gas of hydrogen sulfide contained in waste gas into combustible gas which is an effective energy source of thermal cracking equipment on the premise of safety and environmental protection through a device consisting of a buffer tank, a liquid separating tank, a purifying tank, a desulfurizing tank, a safety tank, a vacuum pump, a corrosion-resistant pump and various control valves, and completely recycle the combustible gas.

Description

Waste gas treatment device and treatment process in waste rubber and plastic pyrolysis

technical field

The invention relates to environmental protection equipment, in particular to a waste gas treatment device and treatment process in the pyrolysis of waste rubber and plastics. the

Background technique

At present, about 5-8% of the non-condensable gas produced in the pyrolysis of waste tires, rubber or waste plastics is waste gas, which includes solid dust, mucus tar, sulfur dioxide and hydrogen sulfide gas. the

Due to the complexity of conventional devices for treating the above-mentioned waste gas, the investment and construction works of the waste gas treatment device occupy 20-30% of the investment cost of the whole set of thermal cracking equipment. In addition, exhaust gas treatment devices need to consume a lot of water resources during operation. Therefore, most waste tire pyrolysis equipment manufacturers and treatment plants do not provide waste gas treatment, but directly discharge this part of the waste gas or directly burn it in the form of a torch, which causes serious environmental pollution and wastes a lot of recyclable waste. energy used. the

Therefore, it is particularly urgent to develop a thermal cracking waste gas treatment equipment with simple device, low equipment investment cost, safety, high efficiency and environmental protection. the

Contents of the invention

In order to overcome the defects of the above-mentioned prior art, the embodiment of the present invention provides a waste gas treatment device and a treatment process in the pyrolysis of waste rubber and plastics. The device has the advantages of simple structure, low investment cost, safety, high efficiency and environmental protection. It has the advantage of easy operation. Described technical scheme is as follows:

A waste gas treatment device in the pyrolysis of waste rubber and plastics, the device includes a buffer tank, a liquid separation tank, a purification tank, a desulfurization tank, a safety tank, a vacuum pump, a corrosion-resistant pump, the second to eighth stop valves, ball valves, gate valves, the first One to five blowdown valves, steam valves, gas respirators and explosion-proof devices;

The buffer tank is used to collect exhaust gas, and the buffer tank is connected to the liquid separation tank through the second shut-off valve, the vacuum pump, and the third shut-off valve, so that the exhaust gas is pumped by the buffer tank through the vacuum pump To the liquid separation tank, the top of the buffer tank is provided with the gas respirator, and the bottom of the buffer tank is provided with a first drain valve, so that the buffer tank is drained;

The liquid separation tank is used to filter out the solid dust and flue gas tar contained in the waste gas, and the upper part of the liquid separation tank is connected to the desulfurization tank through the fourth stop valve, so that the waste gas of the liquid separation tank can flow To the desulfurization tank, the fifth cut-off valve in the middle of the liquid separation tank is connected to the purification tank, so that the solid dust floating on the water surface and the flue gas tar flow through the fifth cut-off valve to the Purification tank, the bottom of the liquid separation tank is provided with a second drain valve to make the liquid separation tank drain, and a steam valve is connected in parallel between the liquid separation tank and the purification tank to remove the liquid separation tank and Smoke and grease remaining in the steam of the purification tank;

The purification tank is used to collect the solid dust and the flue gas tar, and the bottom of the purification tank is provided with the third blowdown valve, so that the purification tank is drained;

The desulfurization tank is used to neutralize the waste gas with the lye in it to form a clean combustible gas. The desulfurization tank is equipped with an lye circulation system, and the lye circulation system includes pipelines connected in sequence The sixth shut-off valve, the corrosion-resistant pump, the gate valve, the ball valve, the eighth shut-off valve and the spray element, wherein the ball valve is an alkali liquid injection nozzle, and the desulfurization tank passes through the The seventh cut-off valve is connected to the safety tank, so that the clean combustible gas is transported to the safety tank, and the bottom of the desulfurization tank is provided with a fourth blowdown valve;

The safety tank is used to store the clean combustible gas, the top of the safety tank is provided with the explosion-proof device, the bottom of the safety tank is provided with the fifth blowdown valve, and the safety tank is provided with Combustible gas outlet. the

Specifically, the vacuum pump is a water ring vacuum pump controlled by PLC and frequency converter. the

Specifically, a smoke filter grid is arranged inside the liquid separation tank, through which the solid dust and smoke tar contained in the waste gas are filtered out. the

Specifically, the spray element is ring-shaped, and the surface of the spray element is provided with uniformly densely distributed micropores, and the lye is pressurized by the corrosion-resistant pump to make the mist sprayed on the micropores of the spray element lye. the

Specifically, the buffer tank is ￠1200×2600mm, the purification tank is ￠440×600mm, the liquid separation tank, the desulfurization tank and the safety tank are all ￠600×1200mm, the buffer tank, The liquid separation tank, the purification tank, the desulfurization tank and the safety tank are all vertically installed and arranged in a straight line. the

Further, the exhaust gas treatment device further includes a first cut-off valve, the first cut-off valve is connected in parallel with the inlet end of the second cut-off valve and the outlet end of the third cut-off valve, and the first cut-off valve is used for Used to adjust the gas flow from the buffer tank to the separator tank. the

The present invention also provides a treatment process for the waste gas treatment device in the cracking of waste rubber and plastics, including the waste gas treatment device in the cracking of waste rubber and plastics, and the treatment process is carried out according to the following steps,

Step 1, waste gas is collected in the buffer tank;

Step 2, the exhaust gas in the buffer tank is pumped by the vacuum pump, so that the exhaust gas passes through the liquid separation tank at a relatively stable flow rate,

Step 3, the flowing waste gas contains a small amount of solid dust and the flue gas tar floating with the waste gas is filtered through the liquid separation tank;

Step 4, the solid dust and flue gas tar floating on the water flow to the purification tank through the fifth stop valve;

Step 5, the exhaust gas continues to flow to the desulfurization tank, and after the neutralization reaction of the lye therein, it becomes a clean combustible gas,

Step 6. After the clean gas passes through the seventh shut-off valve to the safety tank, it goes to the burner to be used as fuel. the

The beneficial effects brought by the technical solution provided by the embodiment of the present invention are: compared with the existing technology, the embodiment of the present invention uses a buffer tank, a liquid separation tank, a purification tank, a desulfurization tank, a safety tank, a vacuum pump, a corrosion-resistant pump and various control The device composed of valves can effectively treat the solid dust, floating oil fume, sulfur dioxide and hydrogen sulfide harmful gases contained in the exhaust gas under the premise of safety and environmental protection, and become an effective energy source for pyrolysis equipment. Combustible gases can be completely recovered Utilization, the present invention not only solves the problem of environmental pollution caused by the disorderly discharge of exhaust gas, but also recycles and utilizes a large amount of renewable energy, reducing the need to consume a large amount of fuel oil or coal resources in thermal cracking. At the same time, the device also has a simple and reasonable structure, The advantages of small occupied area and low investment cost. the

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort. the

Fig. 1 is the overall structural diagram of waste gas treatment device in the cracking of waste rubber and plastic provided by the embodiment of the present invention;

Fig. 2 is the PLC control structural diagram that the embodiment of the present invention provides;

Fig. 3 is the main control structure diagram of the exhaust gas treatment device provided by the embodiment of the present invention;

Fig. 4 is a flow control structure diagram of the exhaust gas treatment device provided by the embodiment of the present invention. the

The meanings of the symbols in the figure are as follows:

1 fuel oil collection tank, 2 buffer tank, 3 liquid separation tank, 4 purification tank, 5 desulfurization tank, 6 safety tank, 7 vacuum pump, 8 corrosion-resistant pump, 9 pressure sensor, 10 digital micro pressure gauge, 11 PLC, 12I/O Modules, 13 cracking kettles, 14 frequency converters;

Va1 first stop valve, Va2 second stop valve, Va3 third stop valve, Va4 fourth stop valve, Va5 fifth stop valve, Va6 sixth stop valve, Va7 seventh stop valve, Va8 eighth stop valve, Va9 ball valve , Va10 gate valve, Va11 first blowdown valve, Va12 second blowdown valve, Va13 third blowdown valve, Va14 fourth blowdown valve, Va15 fifth blowdown valve, Va16 steam valve, Va17 gas respirator, Va18 explosion-proof device;

GS1 smoke filter grille;

PL1 spray element. the

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the implementation manner of the present invention will be further described in detail below in conjunction with the accompanying drawings. the

As shown in Figure 1, a waste gas treatment device in the pyrolysis of waste rubber and plastics provided by the present invention includes a buffer tank 2, a liquid separation tank 3, a purification tank 4, a desulfurization tank 5, a safety tank 6, a vacuum pump 7, a Corrosion pump 8, second to eighth stop valve Va2-Va8, ball valve Va9, gate valve Va10, first to fifth blowdown valve Va11-Va15, steam valve Va16, gas respirator Va17 and explosion-proof device Va18;

The buffer tank 2 is used to collect exhaust gas, and the buffer tank 2 is connected to the liquid separation tank 3 through the second shut-off valve Va2, the vacuum pump 7, and the third shut-off valve Va3, so that the exhaust gas is discharged from the buffer tank. The tank 2 is pumped to the liquid separation tank 3 through the vacuum pump 7, the gas respirator Va17 is provided at the top of the buffer tank 2, and the first blowdown valve Va11 is provided at the bottom of the buffer tank 2, so that the buffer tank 2 tank 2 blowdown;

The liquid separation tank 3 is used to filter the solid dust and flue gas tar contained in the waste gas, and the upper part of the liquid separation tank 3 is connected to the desulfurization tank 5 through the fourth shut-off valve Va4, so that the liquid separation The exhaust gas from the tank 3 flows to the desulfurization tank 5, and the fifth shut-off valve Va5 in the middle of the liquid separation tank 3 is connected to the purification tank 4, so that the solid dust floating on the water surface and the flue gas tar pass through the The fifth cut-off valve Va5 flows to the purification tank 4, and the bottom of the liquid separation tank 3 is provided with a second blowdown valve Va12, so that the liquid separation tank 3 is drained, and the liquid separation tank 3 and the purification tank A steam valve Va16 is connected in parallel between the 4 to get rid of the residual smoke and grease in the steam of the liquid separation tank 3 and the purification tank 4;

The purification tank 4 is used to collect the solid dust and the flue gas tar, and the bottom of the purification tank 4 is provided with the third blowdown valve Va13, so that the purification tank 4 is drained;

The desulfurization tank 5 is used to neutralize the waste gas with the lye in it to form a clean combustible gas. The desulfurization tank 5 is provided with an lye circulation system, which includes a pipeline sequential The sixth shut-off valve Va6, the corrosion-resistant pump 8, the gate valve Va10, the ball valve Va9, the eighth shut-off valve Va8 and the spray element PL1 are connected, wherein the ball valve Va9 is an alkali liquid injection pipe port, the desulfurization tank 5 is connected to the safety tank 6 through the seventh shut-off valve Va7, so that the clean combustible gas is delivered to the safety tank 6, and the bottom of the desulfurization tank 5 is provided with a fourth Drain valve Va14;

The safety tank 6 is used to store the clean combustible gas, the top of the safety tank 6 is provided with the explosion-proof device Va18, the bottom of the safety tank 6 is provided with the fifth drain valve Va15, the The safety tank 6 is provided with a combustible gas outlet. the

As shown in Figure 1, the embodiment of the present invention is composed of a buffer tank 2, a liquid separation tank 3, a purification tank 4, a desulfurization tank 5, a safety tank 6, a vacuum pump 7, a corrosion-resistant pump 8 and various control valves. Under the premise of safety and environmental protection, the solid dust, floating oil fume, sulfur dioxide and hydrogen sulfide harmful gases contained in the exhaust gas are effectively treated to become effective energy and flammable gases for thermal cracking equipment, which can be completely recycled. The present invention not only solves the problem of The disorderly discharge of exhaust gas will cause environmental pollution, and at the same time, a large amount of renewable energy can be recycled to reduce the need to consume a large amount of fuel or coal resources in thermal cracking. the

Specifically, as shown in Figure 1, described vacuum pump 7 is a water ring vacuum pump, and is controlled by PLC 11 and frequency converter 14. the

In this embodiment, the device adopts the water ring vacuum pump 7 to evacuate the medium to circulate and utilize no waste water, and the water consumption is very small. Through the fully closed cycle operation of the water ring vacuum pump 7, it can process 10 tons of waste tires per day in a production line of 10 tons per month. The water consumption is less than 0.5 tons. the

In addition, the use of the water ring vacuum pump 7 can also increase the flow rate of the exhaust gas and stabilize the gas flow rate. The compression of the gas by the water ring vacuum pump 7 is carried out in an isothermal state, so it is not easy to cause danger when pressing or pumping flammable and explosive gases. . the

More specifically, through the function of the buffer tank 2, the exhaust gas can be buffered in the buffer tank 2, and combined with the frequency conversion speed regulation control adopted by the water ring vacuum pump 7, the exhaust gas flow rate can be relatively stable, and the effect of desulfurization is more obvious. The combined use of this process technology and equipment technology has improved the ability to remove solid dust and desulfurize exhaust gas. the

As shown in Figure 2, the power control of described device adopts PLC 11 and frequency converter 14 control, and described device is realized automation, simultaneously, can make cracking kettle 13 internal pressure be in slight negative pressure all the time, improve thermal cracking and get environmental performance, The safety performance of the device is reliable, and the power consumption of the whole device is as little as 4.75KW. By adjusting the vacuum through the frequency conversion, the flow rate of the gas in the flow process is stable, so that the operating load is in a stable energy-saving state and continuously operates the frequency conversion to transport the gas, which can Safety is guaranteed, and the gas flow is stable during the flow process, which can promote the uniformity of the detachment process. the

Specifically, as shown in Figure 2 and Figure 3, a digital micro-pressure gauge 10 is installed on the cracking kettle 13 to detect the amount of waste gas in the kettle, and the signal output of the digital micro-pressure gauge 1 is connected to the I/O module 12 of the PLC 11 The AI terminal of the PLC 11 is used as the analog signal source of the PLC 11. At the same time, the two-wire 4-20mA standard signal pressure sensor 9 is used as the signal source to detect the amount of oil and gas in the kettle. The 4-20mA standard signal passes through the analog quantity input module of the PLC 11. Gathered to PLC 11 controller, in the present embodiment, PLC 11 adopts S7-200 series CPU and I/O module 12 of Siemens, as controller and analog input and output interface, PLC 11 controller CPU reads AI ( Analog input module) 4~20mA signal, according to the size of the AI signal, output a corresponding 2~10V control signal to the AO port (analog output module) after calculation and comparison. Through the curve set by the program, the PLC 11 controller is set to PID adjustment mode and outputs a 4-20mA control signal to directly control the output frequency of the frequency converter 14 according to the control curve close to the program set, so that the water ring vacuum pump 7 can follow the The amount of waste gas represented by the pressure value in the kettle automatically controls the flow rate of the exhaust gas. The frequency converter 14 is set to be controlled by terminals, and the analog quantity is 2-10V control mode. The larger the control signal is, the higher the output frequency of the frequency converter 14 is, and vice versa. the

PLC 11 and inverter 14 automatic control process:

As shown in Figure 2, the pressure sensor 9 micromanometer with digital display is installed on the cracking kettle 13, which can detect the oil and gas volume in the kettle, and convert the pressure value produced by the oil and gas volume into 4-20mA standard signal output. The signal is collected to the PLC 11 controller through the analog input module of PLC 11, and then compared with the control curve set by the program, the PLC 11 controller will output a 4~20mA control signal, and the signal passes through the I/O output module , the signal is converted into a corresponding 2-10V DC voltage signal and connected to the analog signal control terminal of the frequency converter 14, and the control source of the V10 and GND control terminals of the frequency converter 14 is set to analog input control. When the amount of exhaust gas in the kettle is small, the pressure is low and the signal value is small, the control signal output by the PLC 11 controller is also small, the DC voltage value at the inverter 14V10 and GND control terminals is also small, and the output frequency of the inverter 14 is low. The motor speed of 7 is slow and the speed of extracting exhaust gas is slow. On the contrary, as the temperature of cracking kettle 13 rises and the thermal cracking reaction speed becomes faster, the amount of oil and gas produced continues to increase, and the amount of exhaust gas in it is correspondingly more, so it needs to be extracted quickly. At this time, it is necessary to increase the pumping capacity of the water ring vacuum pump 7, and the way to control and increase the speed of the water ring vacuum pump 7 is to increase the output signal of the micromanometer through the increase of the pressure value in the kettle, and increase the output control of the signal received by the PLC 11. The signal also increases, so the 14V10 and GND control signal voltages of the frequency converter also increase accordingly. The output frequency of the frequency converter 14 increases, and the motor speed of the water ring vacuum pump 7 increases accordingly, and the vacuum pumping ability of the water ring vacuum pump 7 increases. As it gets larger, the flow rate of exhaust gas increases accordingly. In the whole control process, the PLC 11 directly controls the output frequency of the frequency converter 14 in the way of PID adjustment according to the control curve close to the program setting, and realizes the automatic control of the pressure value of the water ring vacuum pump 7 corresponding to the amount of oil and gas in the kettle. Speed, this method of closed-loop control can keep the pressure in the kettle always slightly negative, and keeping the cracking kettle 13 always under negative pressure ensures that even if there is a little leakage in the cracking kettle 13, the oil and gas will not leak out, eliminating the need for production on site. Toxic and odorous gases are produced to achieve the purpose of environmental protection and safety of the whole set of equipment. the

It can be seen that the automatic control core technology is to utilize the PLC 11 and the frequency converter 14 in the device to automatically control the rotating speed of the water ring vacuum pump 7, and utilize the buffer tank 2 to stabilize the flow rate of the waste gas to improve the environmental protection and safety performance of the pyrolysis kettle 13 , The desulfurization effect is significantly improved after the exhaust gas flow rate is stable, and the circulating water technology is used to produce no waste water and low energy consumption. the

Specifically, as shown in FIG. 1 , a smoke filter grid GS1 is provided inside the liquid separation tank, through which the solid dust and smoke tar contained in the exhaust gas are filtered out. the

In this embodiment, the liquid in the liquid separation tank 3 is used to remove the solid dust contained in the waste gas, and a simple smoke filter grid is used to filter the floating oil fumes in the waste gas. The soot floating on the liquid surface flows into the purification tank 4. The purpose of recovering this part of the residual oil is mainly to clean the recovered combustible gas and reduce the blockage of the gas pipe caused by the soot staying in the pipeline during the gas transportation process. In this embodiment, the liquid separation tank 3 is used to completely separate the solid dust and the flue gas tar floating with the exhaust gas in the exhaust gas. the

Specifically, as shown in Figure 1, the spray element PL1 is ring-shaped, and the surface of the spray element PL1 is provided with uniform and dense micropores, and the lye is pressurized by the corrosion-resistant pump 8 to make the spray A spray of lye sprayed on the micropores of the component PL1. In this embodiment, through the annular micro-hole spraying in the desulfurization tank 5 and the corrosion-resistant pump 8 cyclic pressurization process, the gas to be treated can be fully integrated with the lye to improve the effect of desulfurization, and the processing capacity is designed according to the actual amount of waste gas generated system capability. the

As a preference, the annular spray element PL1 is made of stainless steel pipe material, and there is a DN20 quick connection on the round pipe, which can be easily connected to the lye pipe. The application of the quick connection makes the annular spray element PL1 is easier to disassemble and assemble. At the same time, there are micropores of 2.5mm uniformly densely distributed on the surface of the round tube. When the corrosion-resistant pump 8 pressurizes the lye to 0.3-0.4MPa, the lye sprayed from the micropores is in the form of mist. , so that the lye and the treated waste gas are fully integrated, the effect of the neutralization reaction is improved, and the desulfurization work is more thorough. the

Specifically, referring to Fig. 1, the buffer tank 2 in this embodiment is ￠1200×2600mm, the purification tank 4 is ￠440×600mm, the liquid separation tank 3, the desulfurization tank 5 and the The safety tanks 6 are all ￠600×1200mm, the buffer tank 2, the liquid separation tank 3, the purification tank 4, the desulfurization tank 5 and the safety tank 6 are all vertically installed and arranged in a straight line , through the above structure, the process pipeline is simple, the device structure is simple and convenient, and the functions of each component are clear, which is beneficial to operation. the

Further, as shown in FIG. 1 , the exhaust gas treatment device further includes a first cut-off valve Va1, which is connected in parallel between the inlet port of the second cut-off valve Va2 and the third cut-off valve Va3. At the outlet end, the first cut-off valve Va1 is used to adjust the gas flow from the buffer tank 2 to the liquid separation tank 3 . the

The specifications and material selection of each component of the device described in this embodiment are as shown in Table 1:

Table 1

label device name Specification material function 2 Buffer tank ￠1200×2600mm carbon steel exhaust buffer 3 Separation tank ￠600×1200mm carbon steel Filter out solid dust in exhaust gas 4 purification tank ￠440×600mm carbon steel Collect residual oil stains in the separatory tank 5 Desulfurization tank ￠600×1200mm carbon steel Neutralization reaction desulfurization 6 Safety jar ￠600×1200mm carbon steel Prevent tempering by water seal 7 Water ring vacuum pump 2BV-5110 carbon steel Vacuum to adjust the gas flow rate 8 Corrosion resistant pump FSB-20 PTFE Neutralizing fluid pressurization the Inverter MCD320-055G the Adjust the speed of the water ring vacuum pump the   Digital Micromanometer -20～+20KPa the Pressure detection and signal source in the kettle Va1 Balancing valve DN50 Pg16 carbon steel Manually adjust the exhaust flow rate

At present, waste tires can produce C1-C20 hydrocarbon gaseous substances in the thermal cracking process, and C5-C20 becomes liquid after condensation, which is our usual fuel oil. It is collected in the fuel collection tank and has 5%-8 % of the non-condensable gases C1-C5 are separated. At present, if these gaseous substances are not continued to be processed and recovered, they will become waste gases and be discharged in an orderly manner or burnt with a torch. After being processed by the device of the present invention, these non-condensable gases are A combustible gas can be fully recycled as an energy source for thermal cracking of waste tires. This work not only ensures the environmental protection and safety issues of thermal cracking, but also provides a large amount of energy for thermal cracking.

As shown in Figure 1, the present invention also provides a treatment process for the waste gas treatment device in the cracking of waste rubber and plastics, including the above-mentioned waste gas treatment device in the cracking of waste rubber and plastics, and the treatment process is carried out according to the following steps,

1. Collect the exhaust gas in the buffer tank 2;

2. The exhaust gas in the buffer tank 2 is pumped by the vacuum pump 7, so that the exhaust gas passes through the liquid separation tank 3 at a relatively stable flow rate,

3. The flowing exhaust gas contains a small amount of solid dust and the flue gas tar floating with the exhaust gas is filtered by the liquid separation tank 3;

4. The solid dust and flue gas tar floating on the water surface flow to the purification tank 4 through the fifth stop valve Va5;

5. The exhaust gas continues to flow to the desulfurization tank 5, and after the neutralization reaction of the lye in it, it becomes a clean combustible gas.

Specifically, the exhaust gas passes through the spray element PL1 in the desulfurization tank 5 and is pressurized by the circulating pump to make the lime water into a mist, and the lime water is fully combined with the combustible gas containing SO2 gas flowing into the desulfurization tank 5 to produce a neutralization reaction. SO2+Ca(OH)2=CaSO3+H2O↓, the chemical and physical stability of the calcium sulfate substance produced after the reaction achieves the purpose of desulfurization, and the final product is gypsum, which is a stable substance insoluble in water and can be used for Building materials and raw materials made of cement, if they are neutralized with alkaline water, sodium sulfite Na2SO3 desulfurization tank 5 can remove more than 90% of SO2 gas

SO ₂ +2Na(OH)=Na ₂ (SO ₃ )+H ₂ O

After being dissolved, the desulfurized substance becomes a clean combustible gas, and finally the water-sealed safety tank 6 is sent to the burner for use as fuel. The gas treated by the desulfurization process can greatly reduce the sulfur content in the flue gas after combustion quantity;

6. After the clean gas passes through the seventh cut-off valve Va7 to the safety tank 6, it goes to the burner to be used as fuel. the

In this embodiment, the waste gas produced in the pyrolysis can be treated in an environmentally friendly manner to achieve safe recycling and energy saving and emission reduction; the process uses multiple processes such as separation, purification, and desulfurization to remove fine dust, SO ₂ , H ₂ S components are effectively removed to become clean combustible gas and recycled, which solves most of the energy required by the thermal cracking process; a water ring vacuum pump 7 is added to the device, which can make the oil and gas produced in the cracking When condensing, the gas and liquid are effectively separated and smoothly sucked into the buffer tank 2, and the gas flow rate is increased to solve the defect that the combustible gas flow rate is unstable and the flame of the burner is unstable; the water ring vacuum pump 7 adopts frequency conversion control and can According to the gas output and process requirements, the speed can be adjusted to achieve energy-saving effect and at the same time, the flow rate of combustible gas can be adjusted; the desulfurization tank 5 adopts lye circulating spray, which can fully integrate with the gas to improve the desulfurization effect.

The invention adopts a brand-new process route to solve the problem of safe and environmentally friendly treatment of pyrolysis waste gas, effectively improves the desulfurization efficiency, has simple equipment structure, small footprint, low cost, strong process innovation, and can realize industrial continuous recycling of waste tires and rubber. And the waste gas discharged from the thermal cracking kettle 13 of waste plastics can make full use of energy, reduce waste gas emissions, save energy and reduce emissions. the

After actually adopting the device of the present invention, the desulfurization effect is obvious, and the combustible gas in the waste gas is fully recycled, and the flue gas discharged is detected by the Shandong Provincial Environmental Protection Monitoring Center Station, and the waste gas discharge: SO The discharge concentration is 96mg/ m3, SO2, and NOx emission concentrations are all in line with (GB13271-2001) Boiler Air Pollutant Emission Standards, and the specific indicators are shown in Table 2:

Table 2. Composition of waste tire pyrolysis exhaust gas: Sample: tire pyrolysis gas

The final decomposed clean gas composition is shown in Table 3:

Table 3. Fuel gas composition analysis Unit: %

Note: The unit of calorific value is MJ/kg. the

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range. the

Claims (7)

1. emission-control equipment in the waste and old rubber cracking; It is characterized in that said device comprises surge tank, divides flow container, purification pot, digester, safety can, vacuum pump, noncorrosive pump, second to the 8th stopping valve, ball valve, gate valve, first to the 5th wash water valve, steam valve, gas respiratory organ and explosion-proof apparatus;

Said surge tank is used to collect waste gas; Said surge tank is connected to said minute flow container through second stopping valve, said vacuum pump, said the 3rd stopping valve; So that waste gas is pumped to said minute flow container through said vacuum pump by said surge tank; Said surge tank top is provided with said gas respiratory organ, and said surge tank bottom is provided with first wash water valve, so that said surge tank blowdown;

Flow container was used for solid dust and tarry matters in smoke that the said waste gas of filtering contains in said minute; Flow container top the 4th stopping valve was connected to said digester in said minute; So that the exhaust-gas flow of said minute flow container to said digester, flow container middle part the 5th stopping valve was connected to said purification pot in said minute, so that said solid dust of bubbling through the water column and said tarry matters in smoke flow to said purification pot through said the 5th stopping valve; Said separatory pot bottom is provided with second wash water valve; So that flow container blowdown in said minute, be parallel with steam valve between said minute flow container and the said purification pot, to get rid of residual flue dust and grease in said minute flow container and the said purification pot steam;

Said purification pot is used to collect said solid dust and said tarry matters in smoke, and the bottom of said purification pot is provided with said the 3rd wash water valve, so that said purification pot blowdown;

Said digester is in order to become said waste gas clean inflammable gas after alkali lye neutralization reaction wherein; Said digester is provided with alkali liquor circulating system; Said alkali liquor circulating system comprises said the 6th stopping valve that is connected in order by pipeline, said noncorrosive pump, said gate valve, said ball valve, said the 8th stopping valve and spray element; Wherein said ball valve is that alkali lye injects the mouth of pipe; Said digester is connected to said safety can through said the 7th stopping valve, so that the inflammable gas of said cleaning is delivered to said safety can, said digester bottom is provided with the 4th wash water valve;

Said safety can is used to deposit the inflammable gas of said cleaning, and the top of said safety can is provided with said explosion-proof apparatus, and the bottom of said safety can is provided with said the 5th wash water valve, and said safety can is provided with the inflammable gas outlet.

2. emission-control equipment in the waste and old rubber cracking as claimed in claim 1 is characterized in that, said vacuum pump is a water ring vacuum pump, and through PLC and Frequency Converter Control.

3. emission-control equipment in the waste and old rubber cracking as claimed in claim 1 is characterized in that, said separatory is irritated inside and is provided with filter cigarette grid, through solid dust and the tarry matters in smoke that contain in the said waste gas of said filter cigarette grid filtering.

4. emission-control equipment in the waste and old rubber cracking as claimed in claim 1; It is characterized in that; Said spray element is an annular, and said spray element surface is provided with the micropore that evenly gathers, and through said noncorrosive pump the alkali lye pressurization is made the vaporific alkali lye that sprays on the micropore of said spray element.

5. emission-control equipment in the waste and old rubber cracking as claimed in claim 1; It is characterized in that; Said surge tank is ￠ 1200 * 2600mm; Said purification pot is ￠ 440 * 600mm, and flow container, said digester and said safety can were ￠ 600 * 1200mm in said minute, and said surge tank, said minute flow container, said purification pot, said digester and said safety can are the vertical type installation and are a straight line and arrange.

6. like emission-control equipment in the described waste and old rubber cracking of each claim of claim 1-5; It is characterized in that; Said emission-control equipment also comprises first stopping valve; Said first stopping valve is connected in parallel on the inlet end of said second stopping valve and the exit end of said the 3rd stopping valve, and said first stopping valve is used for regulating from said surge tank to said minute flow container gas flow.

7. a treatment process that is used for waste and old rubber cracking emission-control equipment is characterized in that, comprises emission-control equipment in the described waste and old rubber cracking of each claim of claim 1-6, and said treatment process carries out according to following step,

Step 1, with gas sampling in said surge tank;

Waste gas in step 2, the said surge tank is pumped through said vacuum pump, makes waste gas pass through said minute flow container with the metastable speed of a kind of flow,

Contain a spot of solid dust in step 3, the mobile waste gas and with the elegant tarry matters in smoke of waste gas through flow container filtering in said minute;

Step 4, the solid dust of bubbling through the water column and tarry matters in smoke flow to said purification pot through said the 5th stopping valve;

Step 5, waste gas continue to flow to said digester, after the neutralization reaction of alkali lye wherein, become clean inflammable gas,

Step 6, said clean gas, use as fuel to combustion engine behind said safety can through said the 7th stopping valve.

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