Method and device for continuously preparing CaC2

Abstract

The invention discloses a device for continuously producing calcium carbide by using new energy abandoned electricity and adopting biomass as a carbon source and a method for continuously preparing CaC2 by adopting the device. According to the device, biomass is adopted as a carbon source, plasma reaction is adopted as a main calcium carbide preparation route, and a combined form of process units such as a CaO preheater, a biomass carbonization furnace / plasma reactor and the like is designed to complete the calcium carbide processing process. According to the reaction device and method disclosed by the invention, aiming at the reaction process of continuously preparing CaC2, through the combined design of the core reactor, the production process of CaC2 is obviously superior to the reaction of preparing calcium carbide by a transmission fixed bed electrothermal method, the reaction speed is high, the retention time of materials is shortened, and the heat loss of a system can be reduced; and secondly, the biomass carbon is a green carbon source, so that the effect of emission reduction can be achieved, and the utilization of the new energy abandoned electricity also plays a role in saving energy.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical synthesis, and in particular, relates to a CaC 2 A continuous preparation method and device, in particular, a method for continuously preparing CaC using new energy electricity and biomass carbon 2 Method and device. Background Art

[0002] Calcium Carbide CaC 2 Commonly known as calcium carbide, it is an important coal chemical product and basic chemical raw material. It is mainly used to produce acetylene and acetylene-based chemical products and was once known as the "mother of organic synthesis industry". 2 The production adopts the method of fixed bed, moving bed, lump raw materials, and arc heating. Due to the small contact area between lump coke and CaO, the solid-solid phase reaction is severely limited by the transfer process, so that the industrial reaction needs to be carried out at high temperature, resulting in "long reaction time, low single furnace capacity, energy consumption per ton up to 3250kWh, calcium carbide purity of about 80%, and thermal efficiency of only 50%. It is of practical value to develop new energy-saving processes.

[0003] Chinese patent CN116288415A introduces a new type of electrolytic preparation of calcium carbide (CaC 2 ) method, which uses a carbonaceous material as a cathode and a compound containing calcium ions as a molten salt, performs cathode electrolysis at a temperature not exceeding 800°C, and obtains calcium carbide from the cathode product. Although this method has a low temperature requirement, it cannot achieve continuous production and has high energy consumption. Chinese patent CN116239120A discloses a method for recycling waste heat of liquid calcium carbide, which is obtained by uniformly mixing carbonaceous raw materials, calcium raw materials, catalysts, binders and foaming agents, pressing molding materials, and performing heat treatment and waterproofing to obtain the first calcium coke. Then the first calcium coke is spread on the bottom of the calcium carbide pot, liquid calcium carbide is added, and the first calcium coke is reacted to synthesize calcium carbide to obtain solid calcium carbide, thereby realizing the recovery of waste heat. This method requires multiple batches of manual operation and cannot achieve continuous production. In addition, the pressed block material affects the reaction mass transfer and heat transfer, thereby affecting the performance of the overall process. Li Guodong's doctoral dissertation at Beijing University of Chemical Technology, "Fundamental Research on a New Process for the Preparation of Calcium Carbide from Powdered Coke and Powdered Calcium Oxide" (Beijing University of Chemical Technology, June 2, 2011), mentioned a new calcium carbide production process, which uses powdered raw materials instead of block raw materials and uses oxygen thermal method instead of arc method, aiming to reduce energy consumption and improve production efficiency. Although this method reduces power consumption, it requires the addition of an oxygen production process, which consumes a lot of energy and chemical raw materials, and does not fully achieve energy conservation. Various patents and research are aimed at energy conservation, which shows how to reduce CaC 2Energy consumption in the production process is the key point to be considered in the process. In terms of carbon source, the existing technology is to increase the final product CaC 2 Coke or activated carbon is often used directly in the quality of biomass. Biomass also contains a large amount of carbon. Due to the collection radius within 100 kilometers, the cost of large-scale collection is high and it is difficult to use effectively. 2 There is no report on using biomass as a carbon source in the production of calcium carbide. The distributed calcium carbide production model can better match the biomass carbon source.

[0004] At the same time, more renewable energy power generation systems are now in operation and supplying electricity to the grid. The main players in renewable energy power generation are wind power and photovoltaic power, and their installed capacity is increasing year by year. Wind and photovoltaic power are non-continuous resources in renewable energy. Power generation is affected by weather conditions, has certain periodic characteristics, and is also highly volatile. On the other hand, electricity consumption patterns also have periodic and volatile characteristics. This mismatch will lead to a large amount of abandoned electricity that cannot be connected to the grid. Using abandoned electricity for product transformation is an effective way to use it.

[0005] Judging from the above existing technologies and developments, the calcium carbide production method that can combine new energy and abandoned electricity while taking into account carbon emission reduction has the dual advantages of being green and low-carbon, and has great application prospects and potential. Summary of the invention

[0006] Technical issues

[0007] The current problems with the calcium carbide process include: high temperature. The existing process uses block raw materials and electric arc heating, which means that the process needs to be carried out at high temperature, increasing energy consumption and investment costs. Due to the small specific surface area of ​​block raw materials, low mass transfer and heat transfer efficiency, slow reaction rate, and high reaction temperature, high energy consumption is required. The thermal efficiency of the product in the fixed bed process is only about 20%, which results in huge energy waste. The reaction rate of block raw materials is slow, the reaction time is long, and the single furnace capacity is low. Equipment durability issues. Arc heating has high requirements for equipment, and there is a problem of short equipment service life.

[0008] In view of the problems existing in the prior art, an object of the present invention is to provide a device for continuously producing calcium carbide by using abandoned electricity from new energy and biomass as a carbon source. The device uses biomass as a carbon source and plasma reaction as the main route for preparing calcium carbide, and designs a combination of process units such as a CaO preheater, a biomass carbonization furnace / plasma reactor to complete the calcium carbide processing process.

[0009] Another object of the present invention is to provide a method for continuously preparing CaC by using the device. 2The method uses biomass char as raw material, firstly, the biomass is made into coke powder in the presence of CaO through a pretreatment device, and then the coke powder loaded with CaO is sprayed into a high-frequency plasma reactor to react and generate CaC 2 , H 2 , CO, etc., through the processes of high-temperature separation of gas and solid, cooling, and recycling of gas phase products to complete the entire treatment process.

[0010] Technical Solution

[0011] According to one aspect of the present invention, the present invention provides an apparatus for continuously preparing calcium carbide, comprising a CaO preheating unit, a carbonization unit, and a plasma reactor;

[0012] The CaO preheating unit comprises: a feeding system, a CaO preheater, and an oil and gas burner system; the CaO preheater is a cylindrical structure, a feeding port is provided on the upper side of the CaO preheater, the feeding port is connected to the feeding system, an air inlet is provided at the bottom of the CaO preheater, the air inlet is connected to the outlet of the oil and gas burner, an air outlet is provided at the top of the CaO preheater for discharging tail gas, and a discharge port is provided on the middle side of the CaO preheater for discharging the preheated material;

[0013] The carbonization unit is located downstream of the CaO preheating unit, and includes a feeding system and a carbonization reactor. The carbonization reactor is a cylindrical structure, and the height-to-diameter ratio of the cylindrical structure is between 3:1 and 6:1. The bottom of the carbonization reactor is provided with an air inlet for inputting a carrier gas, and the upper side of the carbonization reactor is provided with a biomass feed port, and the biomass feed port is connected to the feeding system. The middle side of the carbonization reactor is provided with a CaO feed port, and the CaO feed port is connected to the discharge port of the CaO preheater through a pipeline to receive the preheated CaO from the CaO preheater. The top of the carbonization reactor is provided with an air outlet for discharging pyrolysis gas, and the middle side of the carbonization reactor is also provided with a discharge port for discharging pyrolyzed materials;

[0014] The plasma reactor is located downstream of the CaO preheating unit. The top of the plasma reactor is equipped with a plasma generator. At least one feed port is provided on the upper side of the plasma reactor. The feed port is connected to the discharge port of the carbonization reactor through a pipeline to receive the carbonized material from the carbonization reaction unit. The upper side of the plasma reactor is provided with a gas outlet for conducting gas phase tail gas. The bottom side of the plasma reactor is provided with a gas inlet for introducing carrier gas into the plasma reactor. The middle of the plasma reactor is used as the main reaction zone. The bottom of the plasma reactor is provided with a discharge port for discharging the product CaC 2 mixture.

[0015] Preferably, the feeding system in the CaO preheating unit comprises a silo and a feeder, and the feeder feeds the CaO preheater through a feed port of the CaO preheater. Furthermore, the feeder includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder.

[0016] Preferably, a gas distributor is provided on the inner side of the lower portion of the CaO preheater to control the uniformity of the air flow inside the CaO preheater.

[0017] Preferably, the gas outlet of the CaO preheater is connected to a filter, and the filter is used to remove solid particles in the gas phase tail gas.

[0018] Preferably, optionally, the oil and gas burner is connected to the gas outlet of the carbonization reactor through a pipeline to receive the pyrolysis tail gas from the gas outlet of the carbonization reactor.

[0019] Preferably, the feeding system in the carbonization unit includes a silo and a feeder, and the feeder supplies the biomass raw material to the carbonization reactor through the feed port of the carbonization reactor. Furthermore, the feeder includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder.

[0020] Preferably, the gas outlet of the carbonization reactor is connected to a filter, and the filter is used to remove solid particles in the gas phase mixture.

[0021] Preferably, a gas distributor is provided on the inner side of the lower portion of the carbonization reactor to control the uniformity of the gas flow inside the carbonization reactor.

[0022] Preferably, the gas outlet of the plasma reactor is connected to a filter, and the filter is used to remove solid particles in the gas phase mixture.

[0023] Preferably, the filter includes but is not limited to a screen with corresponding aperture, a cyclone separator, etc.

[0024] Preferably, the discharge port of the plasma reactor is connected to one or more receiving tanks for receiving and separating products.

[0025] Preferably, the CaO preheater and the carbonization reactor are fluidized bed reactors.

[0026] Preferably, the gas distributor provided in the CaO preheater and the carbonization reactor includes but is not limited to a porous plate, a sieve plate, a bubble plate, and the like.

[0027] Preferably, each pipeline in the device for continuously preparing calcium carbide is provided with monitoring elements such as valves, thermometers, and pressure gauges for monitoring the transportation of materials and the operation of the system, for example, for controlling the material flow or the on-off of the pipeline.

[0028] According to another aspect of the present invention, another object of the present invention is to provide a method for continuously preparing calcium carbide using biomass as raw material, the method comprising the following steps:

[0029] 1) Adding CaO particles into the silo of the feeding system of the CaO preheater, adding biomass particles into the silo of the feeding system of the carbonization reactor, and then sealing the entire device for continuously preparing calcium carbide, and checking the air tightness of each unit;

[0030] 2) introducing a carrier gas into the CaO preheater through an air inlet, introducing a carrier gas into the carbonization reactor through an air inlet, and introducing a carrier gas into the plasma reactor through an air inlet, performing replacement of each unit, and starting the device for continuously preparing calcium carbide after the gas phase sampling of the entire reaction device is qualified;

[0031] 3) starting the oil and gas burner of the CaO preheating unit, cutting the high-temperature flue gas into the CaO preheater, and when the specified reaction temperature is reached, opening the feeding system to add CaO into the CaO preheater at a certain rate;

[0032] 4) When the CaO preheater is fluidized normally and reaches the specified temperature and material level, the connecting pipeline between the CaO preheater and the carbonization reactor is connected, the preheated CaO is introduced into the carbonization reactor, and the feeding system of the carbonization unit is simultaneously opened to feed biomass particles into the carbonization reactor, where they are mixed with the high-temperature CaO from the CaO preheater to cause a carbonization reaction. After a certain period of fluidization reaction, a solid mixture of biomass char powder and CaO is led out of the carbonization reactor along with the carrier gas, and introduced into the plasma reactor through a pipeline. The pyrolysis gas is discharged through the outlet gas at the top of the carbonization reactor, and the pyrolysis oil or combustible gas in the fuel gas is recovered through condensation recovery and returned to the oil and gas burner for heating the CaO preheater;

[0033] 5) The plasma reactor receives the solid mixture of biomass coke powder and CaO from the carbonization reactor through a connecting pipeline, and the plasma generator discharges at high frequency in the plasma reactor to react the CaO and biomass coke powder in the mixture to generate CaC 2 The reaction tail gas is discharged through the gas outlet at the top of the carbonization reactor.

[0034] 6) CaC-containing liquid discharged from the discharge port of the plasma reactor 2 The product solid phase mixture is cooled, and the product is subjected to flotation solid phase separation, and after treatment, a calcium carbide product with a purity of more than 98% is obtained.

[0035] Preferably, the tail gas discharged from the gas outlet at the top of the carbonization reactor is filtered and dust-removed, and then pressurized and returned to the oil and gas burner of the CaO preheating unit to provide part of the heat energy for the system as fuel.

[0036] Preferably, the biomass particles are selected from one or more agricultural and forestry crops such as corn stalks, rice husks, wood chips, and fruit shells, with an average particle size of 0.1 to 2 mm, and an optimal particle size of 0.2 to 1 mm. The use of raw materials in this particle size range can increase the pyrolysis carbonization rate of biomass particles and the generation of CaC in the plasma reactor. 2 The speed, energy consumption and other aspects are optimized.

[0037] Preferably, the reaction temperature of the CaO preheater is between 500°C and 1200°C, preferably 800-1000°C, and the reaction pressure is 0.001-0.1MPa, preferably 0.005-0.05MPa. Within this preferred range, the reaction product conversion rate, product yield and production capacity are optimal.

[0038] Preferably, the rate of adding CaO into the CaO preheater is 3-10 kg / h, and the mass ratio of the feeding speed to the fuel is controlled between 1:1 and 5:1.

[0039] Preferably, the mass ratio of CaO to biomass particles in the carbonization reactor is between 1:1 and 4:1, preferably between 1.5:1 and 2:1, and the solid phase residence time is 1 to 30 s, preferably 5 to 20 s. Within this residence time range, the reaction product conversion rate, product yield and production capacity are optimal.

[0040] Preferably, the carrier gas used in the method is selected from CO 2 、N 2 , Ar gas or a combination thereof.

[0041] Preferably, the relationship between the feed rate and the reactor power in the plasma reactor is 1-100 g / kw, and the optimal feed rate is 5-50 g / kw. Within the optimal ratio range, corresponding to the same output, the raw material consumption and the system energy consumption are optimal.

[0042] Preferably, the reaction temperature in the plasma reactor is 1200-2400° C., and the preferred reaction temperature is 1400-1800° C. Under this reaction condition, the product conversion rate, product yield and production capacity are optimal.

[0043] Preferably, the plasma generator in the plasma reactor uses abandoned electricity from wind power or solar power generation as energy.

[0044] Preferably, the tail gas discharged from the gas outlet of the plasma reactor passes through the filter and then enters a separation system to collect combustible gas and then is introduced into the oil and gas burner for use as fuel.

[0045] Beneficial Effects

[0046] The reaction device and method of the present invention are aimed at continuously preparing CaC 2 The reaction process, especially for the utilization of biomass carbon sources and new energy abandoned electricity, through the combined design of the core reactor, makes CaC 2 The production process is significantly better than the reaction of preparing calcium carbide by the transmission fixed bed electrothermal method. The reaction process is disassembled into multi-step reaction treatment. First, the high-temperature CaO provided by the CaO preheater provides the heat source. The energy comes from biomass cracking oil and gas or external energy. The biomass and other raw materials are first carbonized in the carbonization reactor. At the same time, the attachment and distribution of CaO on the biomass carbon are realized, which well solves the problem of the ratio and mass transfer of the two substances in the plasma reactor. In addition, the powder reactants maximize the mass transfer reaction rate, and the efficiency of the plasma reactor is most effectively utilized. The plasma reactor has a very fast reaction speed, which reduces the residence time of the material and can also reduce the heat loss of the system; secondly, biomass carbon is a green carbon source, which can achieve the effect of emission reduction, and the utilization of new energy abandoned electricity also plays a role in energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar parts. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the specification and claims, are used to illustrate the embodiments of the invention. When appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

[0048] Figure 1 According to a method for continuously producing CaC 2 Schematic diagram of the structure of the device.

[0049] Reference numerals:

[0050] CaO preheating unit:

[0051] 1-Feeding system: 11-silo / storage tank, 12-feeder / feeding pump;

[0052] 2-Oil and gas burners;

[0053] 3-CaO preheater: 31-feed port, 32-discharge port, 33-air inlet, 34-gas distributor, 35-air outlet, 36-filter;

[0054] Carbonization unit:

[0055] 4-Feeding system: 41-silo / storage tank, 42-feeder / feeding pump;

[0056] 5-carbonization reactor: 50-CaO feed port, 51-biomass feed port, 52-discharge port, 53-air inlet, 54-gas distributor, 55-air outlet, 56-filter;

[0057] 6-plasma reactor: 60-feed port, 61-air inlet, 62-discharge port, 63, 64-receiving tank, 65-air outlet, 66-filter. DETAILED DESCRIPTION

[0058] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings, but are not intended to limit the present invention.

[0059] It should be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the following description should not be considered as limiting, but merely as an example of an embodiment. Other modifications within the scope and spirit of the present disclosure will occur to those skilled in the art.

[0060] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

[0061] These and other characteristics of the invention will become apparent from the following description of a preferred form of embodiment given as a non-limiting example, with reference to the accompanying drawings.

[0062] It should also be understood that, although the invention has been described with reference to some specific examples, those skilled in the art will be able to realize many other equivalent forms of the invention that have the characteristics recited in the claims and are therefore within the scope of protection defined thereby.

[0063] The above and other aspects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0064] Specific embodiments of the present disclosure are described hereinafter with reference to the accompanying drawings; however, it should be understood that the disclosed embodiments are merely examples of the present disclosure, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant details. Therefore, the specific structural and functional details disclosed herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present disclosure in a variety of ways with substantially any suitable detailed structure.

[0065] This specification may use the phrases "in one embodiment," "in another embodiment," "in a further embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0066] Reference below Figure 1 The continuous reaction of the present invention is specifically described to prepare CaC 2 The structure of the method and device mainly includes: a CaO preheating unit, a carbonization reaction unit, a plasma reaction unit, etc.:

[0067] Among them, the CaO preheating unit includes: a feeding system 1, a CaO preheater 3, and an oil and gas burner 2 system; the CaO preheater 1 is a cylindrical structure, and a feeding port 31 is provided on the upper side of the CaO preheater 1, and the feeding port 31 is connected to the feeding system 1, and an air inlet 33 is provided at the bottom of the CaO preheater 3, and the air inlet 33 is connected to the outlet of the oil and gas burner 2, and an air outlet 35 is provided on the top of the CaO preheater 3 for discharging tail gas, and a discharge port 32 is provided on the middle side of the CaO preheater 3 for discharging the preheated material.

[0068] Preferably, the feeding system 1 comprises a silo or storage tank 11 and a feeder or feeding pump 12, and the feeder or feeding pump 12 feeds the CaO preheater 3 through a feed port 31 of the CaO preheater 3. The feeder or feeding pump 12 includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder.

[0069] Preferably, a gas distributor 34 is provided on the inner side of the lower portion of the CaO preheater 3 to control the hot air flow entering the CaO preheater 3 so as to make the interior of the CaO preheater 3 uniformly fluidized.

[0070] Preferably, the gas outlet 35 of the CaO preheater 3 is connected to a filter 36, and the filter 36 is used to remove solid particles in the gas phase tail gas.

[0071] Preferably, the oil and gas burner 2 can also be connected to the gas outlet 55 or the filter 56 of the carbonization reactor 5 through a pipeline to receive the pyrolysis tail gas containing combustible oil and gas from the carbonization reactor 5 .

[0072] The carbonization unit is located downstream of the CaO preheating unit, and includes a feeding system 4 and a carbonization reactor 5. The carbonization reactor 5 is a cylindrical structure with a height-to-diameter ratio of 3:1 to 6:1. An air inlet 53 is provided at the bottom of the carbonization reactor 5 for inputting a carrier gas. A biomass feed port 51 is provided on the upper side of the carbonization reactor 5, and the biomass feed port 51 is connected to the feeding system 4. A CaO feed port 50 is provided on the middle side of the carbonization reactor 5, and the CaO feed port 50 is connected to the discharge port 32 of the CaO preheater 3 through a pipeline to receive the preheated CaO from the CaO preheater 3. An air outlet 55 is provided on the top of the carbonization reactor 5 for discharging pyrolysis gas. A discharge port 52 is also provided on the middle side of the carbonization reactor 5 for discharging pyrolyzed materials.

[0073] Preferably, the feeding system 4 in the carbonization unit includes a silo / storage tank 41 and a feeder / feeding pump 42, and the feeder / feeding pump 42 supplies the biomass raw material to the carbonization reactor 5 through the feed port 51 of the carbonization reactor 5. Furthermore, the feeder / feeding pump 42 includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder.

[0074] Preferably, the gas outlet 55 of the carbonization reactor 5 is connected to a filter 56, and the filter 56 is used to remove solid particles in the gas phase mixture.

[0075] Preferably, a gas distributor 54 is provided on the inner side of the lower portion of the carbonization reactor 5 to control the hot air flow entering the carbonization reactor 5 so as to make the interior of the carbonization reactor 5 uniformly fluidized.

[0076] The plasma reactor 6 is located downstream of the CaO preheating unit. The top of the plasma reactor 6 is equipped with a plasma generator. At least one feed port 60 is provided on the upper side of the plasma reactor 6. The feed port 60 is connected to the discharge port 52 of the carbonization reactor 5 through a pipeline to receive the carbonized material from the carbonization reaction unit. An outlet 65 is provided on the upper side of the plasma reactor 6 for conducting gaseous tail gas. An inlet 61 is provided on the bottom side of the plasma reactor 6 for introducing carrier gas into the plasma reactor 6. The middle of the plasma reactor 6 serves as the main reaction zone. An outlet 62 is provided at the bottom of the plasma reactor 6 for discharging the product CaC 2 mixture.

[0077] Preferably, the carrier gas in the plasma reactor 6 can also enter the plasma reactor 6 through the feed inlet 60 together with the material from the carbonization reactor 5 through a pipeline.

[0078] Preferably, the gas outlet 65 of the plasma reactor 6 is connected to a filter 66, and the filter 66 is used to remove solid particles in the gas phase mixture.

[0079] Preferably, the discharge port 62 of the plasma reactor 6 is connected to one or more receiving tanks 63 and 64 for receiving and separating products.

[0080] Preferably, the CaO preheater 3 and the carbonization reactor 5 are fluidized bed reactors.

[0081] Preferably, the gas distributors 34 and 54 provided in the CaO preheater 3 and the carbonization reactor 5 include but are not limited to porous plates, sieve plates, bubble plates, and the like.

[0082] Preferably, the filters 36, 56 and 66 include but are not limited to screens with corresponding apertures, cyclone separators, etc.

[0083] Preferably, as needed, each pipeline in the device for continuously preparing calcium carbide according to the present invention may be provided with monitoring elements such as valves, thermometers, and pressure gauges for monitoring the transportation of materials and the operation of the system, for example, for controlling the material flow or the on-off of the pipeline.

[0084] refer to Figure 1 According to the method for continuously preparing calcium carbide using biomass as raw material of the present invention, the method comprises the following steps:

[0085] 1) Adding CaO particles into the silo 11 of the feeding system of the CaO preheater 3, adding biomass particles into the silo 41 of the feeding system of the carbonization reactor 5, and then sealing the entire device for continuously preparing calcium carbide, cutting off the valve of the pipeline connecting the CaO preheater 3 and the carbonization reactor 5, cutting off the valve of the pipeline connecting the carbonization reactor 5 and the plasma reactor 6, and checking the air tightness of each unit, performing gas replacement, and respectively introducing CO into the CaO preheater 3, the carbonization reactor 5 and the plasma reactor 6; 2 Gas, and check the air tightness of each unit;

[0086] 2) After the gas phase sampling of the entire reaction device is qualified, starting the device for continuously preparing calcium carbide;

[0087] 3) starting the oil and gas burner 2 of the CaO preheating unit, introducing air and necessary fuel gas therein, cutting the generated high-temperature flue gas into the CaO preheater 3, and when the specified reaction temperature is reached, opening the feeding system 1, and adding CaO into the CaO preheater 3 at a certain rate;

[0088] 4) When the CaO preheater 3 is fluidized normally and reaches the specified temperature and material level, the connecting pipeline between the CaO preheater 3 and the carbonization reactor 5 is connected, the preheated CaO is introduced into the carbonization reactor 5, and the feeding system 4 of the carbonization unit is simultaneously opened to feed the biomass particles into the carbonization reactor 5, and mix with the high-temperature CaO from the CaO preheater 3 to cause a carbonization reaction. After a certain period of fluidization reaction, the solid mixture of biomass char powder and CaO is led out of the carbonization reactor 5 with the carrier gas, and introduced into the plasma reactor 6 through a pipeline. The pyrolysis gas is discharged through the outlet gas 55 at the top of the carbonization reactor 5, and the pyrolysis oil or combustible gas in the fuel gas is recovered through condensation recovery and returned to the oil and gas burner 2 for heating the CaO preheater;

[0089] 5) The plasma reactor 6 receives the solid mixture of biomass coke powder and CaO from the carbonization reactor 5 through a connecting pipeline, and the plasma generator discharges at high frequency in the plasma reactor 6 to react the CaO and biomass coke powder in the mixture to generate CaC 2 The reaction tail gas is discharged through the gas outlet 65 at the top of the carbonization reactor 6.

[0090] 6) The CaC-containing liquid discharged from the discharge port 62 of the plasma reactor 6 2 The product solid phase mixture is cooled, and the product is subjected to flotation solid phase separation, and after treatment, a calcium carbide product with a purity of more than 98% is obtained.

[0091] Preferably, the tail gas discharged from the gas outlet 55 at the top of the carbonization reactor 5 is filtered and dust-removed, and then pressurized and returned to the oil and gas burner 2 of the CaO preheating unit to provide part of the heat energy for the system as fuel.

[0092] Preferably, the biomass particles are selected from one or more agricultural and forestry crops such as corn stalks, rice husks, wood chips, and fruit shells, with an average particle size of 0.1 to 2 mm, and an optimal particle size of 0.2 to 1 mm. The use of raw materials in this particle size range can increase the pyrolysis carbonization rate of biomass particles and the generation of CaC in the plasma reactor. 2 The speed, energy consumption and other aspects are optimized.

[0093] Preferably, the reaction temperature of the CaO preheater is between 500°C and 1200°C, preferably 800-1000°C, and the reaction pressure is 0.001-0.1MPa, preferably 0.005-0.05MPa. Within this preferred range, the reaction product conversion rate, product yield and production capacity are optimal.

[0094] Preferably, the rate of adding CaO into the CaO preheater is 3-10 kg / h, and the mass ratio of the feeding speed to the fuel is controlled between 1:1 and 5:1.

[0095] Preferably, the mass ratio of CaO to biomass particles in the carbonization reactor is between 1:1 and 4:1, preferably between 1.5:1 and 2:1, and the solid phase residence time is 1 to 30 s, preferably 5 to 20 s. Within this residence time range, the reaction product conversion rate, product yield and production capacity are optimal.

[0096] Preferably, the carrier gas used in the method is selected from CO 2 、N 2 , Ar gas or a combination thereof.

[0097] Preferably, the relationship between the feed rate and the reactor power in the plasma reactor is 1-100 g / kw, and the optimal feed rate is 5-50 g / kw. Within the optimal ratio range, corresponding to the same output, the raw material consumption and the system energy consumption are optimal.

[0098] Preferably, the reaction temperature in the plasma reactor is 1200-2400° C., and the preferred reaction temperature is 1400-1800° C. Under this reaction condition, the product conversion rate, product yield and production capacity are optimal.

[0099] Preferably, the plasma generator in the plasma reactor preferentially uses abandoned electricity from wind power or solar power generation as energy.

[0100] Preferably, the tail gas discharged from the gas outlet of the plasma reactor passes through the filter and then enters a separation system to collect combustible gas and then is introduced into the oil and gas burner for use as fuel.

[0101] The following examples are only listed as examples of embodiments of the present invention and do not constitute any limitation to the present invention. It can be understood by those skilled in the art that modifications within the scope of the essence and concept of the present invention fall within the scope of protection of the present invention. Unless otherwise specified, the reagents and instruments used in the following examples are commercially available products.

[0102] Embodiment 1:

[0103] The selected CaO preheater is: reaction section Φ100mm, total length about 800mm, single-stage pressurized fluidized bed reactor, material loading about 3kg, carbonization reactor and CaO preheater of the same size, plasma reactor power 10kW.

[0104] 1) After the system gas is replaced, the oil and gas burner 2 of the CaO preheating unit is started, and the high-temperature flue gas is introduced into the CaO preheater 3 through the air inlet 33 of the CaO preheater 3, and the fuel flow rate is controlled at 0.1L / min. The feeding system 1 is opened to introduce CaO into the CaO preheater 3 at a rate of 3 to 10kg / h. When the CaO preheater 3 reaches a specified temperature, the slide valve on the connecting pipeline between the CaO preheater 3 and the carbonization reactor 5 is opened to continuously introduce the material into the carbonization reactor 5, and the extraction rate is equal to the feeding rate;

[0105] 2) Synchronously start the feeding system 4 of the carbonization reactor 5, introduce biomass particles with a diameter of 0.1 to 2 mm, with an optimal particle size of 0.2 to 1 mm, into the carbonization reactor 5, with a biomass addition rate of 3 to 10 kg / h and a solid phase residence time of 10 to 100 s. When the specified temperature is reached, open the connecting pipeline between the carbonization reactor 5 and the plasma reactor 6, and introduce the material into the plasma reactor 6;

[0106] 3) Turn on the plasma reactor 6. The power of the plasma reactor comes from the abandoned electricity of new energy, that is, the new energy electricity that cannot be connected to the grid. When the CaO and biomass carbon mixture is introduced into the plasma reactor 6, it reacts under the action of high-frequency current to generate CaC 2 , CO, H 2 etc., CaC at high temperature 2 For liquid, CaC 2 The small droplets enter the receiving tanks 63 and 64 through the discharge port 62, and cool the gas CO 2 It becomes solid CaC 2 The particles are collected after cooling;

[0107] 4) The tail gas of the carbonization reactor 5 is biomass oil gas, which is returned to the oil and gas burner 2 of the CaO preheating unit after purification, and further burned to generate high-temperature flue gas for heating CaO.

[0108] The plasma reaction was carried out using three different ratios of CaO and biochar. When the air velocity of the carbonization reactor 5 was 0.01 h -1 When the reaction temperature is 550°C and the pressure is 0.1MPa, when the reaction temperature of the plasma reactor 6 is 1500°C and the pressure is 0.01MPa, the results are as follows:

[0109] Result 1: CaO and biomass carbon mass ratio is 2:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 68%, and the by-product selectivity is 32%;

[0110] Result 2: CaO and biomass carbon mass ratio is 3:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 82%, and the by-product selectivity is 18%;

[0111] Result 3: CaO and biomass carbon mass ratio is 4:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 79% and the by-product selectivity is 21%.

[0112] Embodiment 2:

[0113] The selected CaO preheater is: reaction section Φ100mm, total length about 800mm, single-stage pressurized fluidized bed reactor, material loading about 3kg, carbonization reactor and CaO preheater of the same size, plasma reactor power 10kW.

[0114] 1) After the system gas is replaced, the oil and gas burner 2 of the CaO preheating unit is started, and the high-temperature flue gas is introduced into the CaO preheater 3 through the air inlet 33 of the CaO preheater 3, and the fuel flow rate is controlled at 0.1L / min. The feeding system 1 is opened to introduce CaO into the CaO preheater 3 at a rate of 3 to 10kg / h. When the CaO preheater 3 reaches a specified temperature, the slide valve on the connecting pipeline between the CaO preheater 3 and the carbonization reactor 5 is opened to continuously introduce the material into the carbonization reactor 5, and the extraction rate is equal to the feeding rate;

[0115] 2) Synchronously start the feeding system 4 of the carbonization reactor 5, introduce biomass particles with a particle size between 0.1 and 2 mm, with an optimal particle size between 0.2 and 1 mm, into the carbonization reactor 5, the biomass addition rate is 3 to 10 kg / h, and the solid phase residence time is 10 to 100 s. When the specified temperature is reached, open the connecting pipeline between the carbonization reactor 5 and the plasma reactor 6, and introduce the material into the plasma reactor 6;

[0116] 3) Turn on the plasma reactor 6. The power of the plasma reactor comes from the abandoned electricity of new energy, that is, the new energy electricity that cannot be connected to the grid. When the CaO and biomass carbon mixture is introduced into the plasma reactor 6, it reacts under the action of high-frequency current to generate CaC 2 , CO, H 2 etc., CaC at high temperature 2 For liquid, CaC 2 The small droplets enter the receiving tanks 63 and 64 through the discharge port 62, and cool the gas CO 2It becomes solid CaC 2 The particles are collected after cooling;

[0117] 4) The tail gas of the carbonization reactor 5 is biomass oil gas, which is returned to the oil and gas burner 2 of the CaO preheating unit after purification, and further burned to generate high-temperature flue gas for heating CaO;

[0118] Three different ratios of CaO and biochar were used to perform the above CaC 2 Reaction, when the carbonization reactor space velocity is 0.01h -1 , when the reaction temperature is 600℃, the pressure is 0.1MPa, when the plasma reactor reaction temperature is 1800℃, the pressure is 0.01MPa, the results are as follows:

[0119] Result 1: CaO and biomass carbon mass ratio is 2:1: biomass carbon conversion rate is 85%, CaC 2 The selectivity is 70%, and the by-product selectivity is 30%;

[0120] Result 2: CaO and biomass carbon mass ratio is 3:1: biomass carbon conversion rate is 89%, CaC 2 The selectivity is 84%, and the by-product selectivity is 16%;

[0121] Result 3: CaO and biomass carbon mass ratio is 4:1: biomass carbon conversion rate is 86%, CaC 2 The selectivity is 80%, and the by-product selectivity is 20%.

[0122] Embodiment 3:

[0123] The selected CaO preheater is: reaction section Φ100mm, total length about 800mm, single-stage pressurized fluidized bed reactor, material loading about 3kg, carbonization reactor and CaO preheater of the same size, plasma reactor power 10kW.

[0124] 1) After the system gas is replaced, the oil and gas burner 2 of the CaO preheating unit is started, and the high-temperature flue gas is introduced into the CaO preheater 3 through the air inlet 33 of the CaO preheater 3, and the fuel flow rate is controlled at 0.1L / min. The feeding system 1 is opened to introduce CaO into the CaO preheater 3 at a rate of 3 to 10kg / h. When the CaO preheater 3 reaches a specified temperature, the slide valve on the connecting pipeline between the CaO preheater 3 and the carbonization reactor 5 is opened to continuously introduce the material into the carbonization reactor 5, and the outlet rate is controlled to be equal to the feeding rate;

[0125] 2) Synchronously start the feeding system 4 of the carbonization reactor 5, introduce biomass particles with a diameter of 0.1 to 2 mm, with an optimal particle size of 0.2 to 1 mm, into the carbonization reactor 5, with a biomass addition rate of 3 to 10 kg / h and a solid phase residence time of 10 to 100 s. When the specified temperature is reached, open the connecting pipeline between the carbonization reactor 5 and the plasma reactor 6, and introduce the material into the plasma reactor 6;

[0126] 3) Turn on the plasma reactor 6. The power of the plasma reactor comes from the abandoned electricity of new energy, that is, the new energy electricity that cannot be connected to the grid. When the CaO and biomass carbon mixture is introduced into the plasma reactor 6, it reacts under the action of high-frequency current to generate CaC 2 , CO, H 2 etc., CaC at high temperature 2 For liquid, CaC 2 The small droplets enter the receiving tanks 63 and 64 through the discharge port 62, and cool the gas CO 2 It becomes solid CaC 2 The particles are collected after cooling;

[0127] 4) The tail gas of the carbonization reactor 5 is biomass oil gas, which is returned to the oil and gas burner 2 of the CaO preheating unit after purification, and further burned to generate high-temperature flue gas for heating CaO;

[0128] Three different ratios of CaO and biochar were used to perform the above CaC 2 Reaction, when the carbonization reactor space velocity is 0.01h -1 When the reaction temperature is 550°C and the pressure is 0.1MPa, when the plasma reactor reaction temperature is 1500°C and the pressure is 0.01MPa, the results are as follows:

[0129] Result 1: CaO and coal coke mass ratio is 3:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 74%, and the by-product selectivity is 26%;

[0130] Result 2: CaO and biomass carbon mass ratio is 3:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 88%, and the by-product selectivity is 12%;

[0131] Result 3: CaO and petroleum coke mass ratio is 3:1: biomass carbon conversion rate is 75%, CaC 2 The selectivity is 79% and the by-product selectivity is 21%.

[0132] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents, without departing from the spirit and essence of the claims of the present invention; and these modifications or replacements are still within the scope defined by the claims of the present invention.

Claims

1. A device for continuously preparing calcium carbide, comprising a CaO preheating unit, a carbonization unit, and a plasma reactor; in, The CaO preheating unit comprises: a feeding system, a CaO preheater, and an oil and gas burner system; the CaO preheater is a cylindrical structure, a feeding port is provided on the upper side of the CaO preheater, the feeding port is connected to the feeding system, an air inlet is provided at the bottom of the CaO preheater, the air inlet is connected to the outlet of the oil and gas burner, an air outlet is provided on the top of the CaO preheater for discharging tail gas, and a discharge port is provided on the middle side of the CaO preheater for discharging the preheated material; The carbonization unit is located downstream of the CaO preheating unit, and includes a feeding system and a carbonization reactor. The carbonization reactor is a cylindrical structure, and the height-to-diameter ratio of the cylindrical structure is between 3:1 and 6:

1. The bottom of the carbonization reactor is provided with an air inlet for inputting a carrier gas, and the upper side of the carbonization reactor is provided with a biomass feed port, and the biomass feed port is connected to the feeding system. The middle side of the carbonization reactor is provided with a CaO feed port, and the CaO feed port is connected to the discharge port of the CaO preheater through a pipeline to receive the preheated CaO from the CaO preheater. The top of the carbonization reactor is provided with an air outlet for discharging pyrolysis gas, and the middle side of the carbonization reactor is also provided with a discharge port for discharging pyrolyzed materials; The plasma reactor is located downstream of the CaO preheating unit, the top of the plasma reactor is equipped with a plasma generator, the upper side of the plasma reactor is provided with at least one feed port, the feed port is connected to the discharge port of the carbonization reactor through a pipeline, and receives the carbonized material from the carbonization reaction unit; the upper side of the plasma reactor is provided with a gas outlet for conducting gas phase tail gas; the bottom side of the plasma reactor is provided with a gas inlet for introducing carrier gas into the plasma reactor; the middle of the plasma reactor serves as the main reaction zone; the bottom of the plasma reactor is provided with a discharge port for discharging a mixture containing the product CaC2.

2. The device for continuously preparing calcium carbide according to claim 1, characterized in that: The feeding system in the CaO preheating unit comprises a silo and a feeder, and the feeder feeds the CaO preheater through the feed port of the CaO preheater; Furthermore, the feeder includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder; Preferably, a gas distributor is provided on the inner side of the lower part of the CaO preheater to control the uniformity of the gas flow inside the CaO preheater; Preferably, the gas outlet of the CaO preheater is connected to a filter, and the filter is used to remove solid particles in the gas phase tail gas; Preferably, optionally, the oil and gas burner is connected to the gas outlet of the carbonization reactor through a pipeline to receive the pyrolysis tail gas from the gas outlet of the carbonization reactor; Preferably, the feeding system in the carbonization unit comprises a silo and a feeder, and the feeder supplies the biomass raw material to the carbonization reactor through the feed port of the carbonization reactor; further, the feeder includes but is not limited to pneumatic conveying, a screw feeder, or a star feeder; Preferably, the gas outlet of the carbonization reactor is connected to a filter, and the filter is used to remove solid particles in the gas phase mixture; Preferably, a gas distributor is provided on the inner side of the lower part of the carbonization reactor to control the uniformity of the gas flow inside the carbonization reactor; Preferably, the gas outlet of the plasma reactor is connected to a filter, and the filter is used to remove solid particles in the gas phase mixture; Preferably, the filter includes but is not limited to a screen with corresponding aperture, a cyclone separator; Preferably, the discharge port of the plasma reactor is connected to one or more receiving tanks for receiving and separating products; Preferably, the CaO preheater and the carbonization reactor are fluidized bed reactors; Preferably, the gas distributor provided in the CaO preheater and the carbonization reactor includes but is not limited to a porous plate, a sieve plate, and a bubble cap plate; Preferably, each pipeline in the device for continuously preparing calcium carbide is provided with valves, thermometers, pressure gauge monitoring elements for monitoring the transportation of materials and the operation of the system.

3. A method for continuously preparing calcium carbide using biomass as raw material, the method comprising the following steps: 1) Adding CaO particles into the silo of the feeding system of the CaO preheater, adding biomass particles into the silo of the feeding system of the carbonization reactor, and then sealing the entire device for continuously preparing calcium carbide, and checking the air tightness of each unit; 2) introducing a carrier gas into the CaO preheater through an air inlet, introducing a carrier gas into the carbonization reactor through an air inlet, and introducing a carrier gas into the plasma reactor through an air inlet, performing replacement of each unit, and starting the device for continuously preparing calcium carbide after the gas phase sampling of the entire reaction device is qualified; 3) starting the oil and gas burner of the CaO preheating unit, cutting the high-temperature flue gas into the CaO preheater, and when the specified reaction temperature is reached, opening the feeding system to add CaO into the CaO preheater at a certain rate; 4) When the CaO preheater is fluidized normally and reaches the specified temperature and material level, the connecting pipeline between the CaO preheater and the carbonization reactor is connected, the preheated CaO is introduced into the carbonization reactor, and the feeding system of the carbonization unit is simultaneously opened to feed biomass particles into the carbonization reactor, where they are mixed with the high-temperature CaO from the CaO preheater to cause a carbonization reaction. After a certain period of fluidization reaction, a solid mixture of biomass char powder and CaO is led out of the carbonization reactor along with the carrier gas, and introduced into the plasma reactor through a pipeline. The pyrolysis gas is discharged through the outlet gas at the top of the carbonization reactor, and the pyrolysis oil or combustible gas in the fuel gas is recovered through condensation recovery and returned to the oil and gas burner for heating the CaO preheater; 5) The plasma reactor receives a solid mixture of biomass coke powder and CaO from the carbonization reactor through a connecting pipeline, and the plasma generator discharges at high frequency in the plasma reactor to react the CaO and biomass coke powder in the mixture to generate CaC2, and the reaction tail gas is discharged through the gas outlet at the top of the carbonization reactor; 6) The solid phase mixture containing CaC2 discharged from the discharge port of the plasma reactor is cooled, and the product is subjected to flotation solid phase separation, and a calcium carbide product with a purity of more than 98% is obtained after treatment.

4. The method for continuously preparing calcium carbide using biomass as raw material according to claim 3, characterized in that: The tail gas discharged from the gas outlet at the top of the carbonization reactor is filtered and dust-removed, then pressurized and returned to the oil and gas burner of the CaO preheating unit to provide part of the heat energy for the system as fuel; Preferably, the biomass particles are selected from one or more agricultural and forestry crops such as corn stalks, rice husks, wood chips, and fruit shells, with an average particle size of 0.1 to 2 mm, and an optimal particle size of 0.2 to 1 mm; Preferably, the reaction temperature of the CaO preheater is between 500°C and 1200°C, preferably 800-1000°C, and the reaction pressure is 0.001-0.1MPa, preferably 0.005-0.05MPa; Preferably, the rate of adding CaO to the CaO preheater is 3 to 10 kg / h, and the feeding speed is controlled to be in a ratio of 1:1 to 5:1 to the fuel mass; Preferably, the mass ratio of CaO to biomass particles in the carbonization reactor is between 1:1 and 4:1, preferably between 1.5:1 and 2:1, and the solid phase residence time is 1 to 30 seconds, preferably 5 to 20 seconds; Preferably, the carrier gas used in the method is selected from CO2, N2, Ar gas or a combination thereof; Preferably, the relationship between the feed rate and the reactor power in the plasma reactor is 1 to 100 g / kw, and the optimal feed rate is 5 to 50 g / kw; Preferably, the reaction temperature in the plasma reactor is 1200-2400°C, and the preferred reaction temperature is 1400-1800°C; Preferably, the plasma generator in the plasma reactor uses abandoned electricity from wind power or solar power generation as energy; Preferably, the tail gas discharged from the gas outlet of the plasma reactor passes through the filter and then enters a separation system to collect combustible gas and then is introduced into the oil and gas burner for use as fuel.

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