Cement production system coupled with biomass energy
By introducing a gasification furnace into the cement production system, the biomass is gasified into syngas fuel, and reacted with hot feed to remove chlorine in the gasification furnace, the high chlorine content and energy waste of cement clinker caused by chloride ions in the biomass is solved, and the effect of chloride ion removal and energy consumption saving is achieved.
Patent Information
- Application Number
- CN202421610562.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-09
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-07-09
AI Technical Summary
When using biomass instead of fuel in cement kilns, the biomass contains more chloride ions, resulting in a high chlorine content in cement clinker, which affects the thermal system of the decomposition furnace and causes energy waste.
A cement production system coupled with biomass energy was designed, and the biomass was gasified through a gasification furnace to form gas synthesis gas fuel such as CO, H2, and sent to the decomposition furnace to replace part of the fuel. In the gasification furnace, the hot feed reacts with chloride ions to cure the chloride ions into the residue in the furnace, which has the effect of removing chlorine. The residue produced by the gasifier is added to the cement as a mixture.
It effectively reduces the chloride ion content in cement clinker, reduces energy waste, and uses low-temperature hot air at the kiln head to dry the biomass, saving energy consumption.
Smart Images
Figure CN222951542U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of cement production, and relates to a cement production system coupled with biomass energy. Background Art
[0002] In the traditional cement clinker production process, there are a large number of industrial heating processes. The ways to use electricity for industrial heating include resistance heating, arc thermal plasma technology, etc. 30% of carbon emissions come from the combustion of fossil fuels such as coal. In order to achieve carbon neutrality in the cement industry, it is urgent to explore the use of clean energy such as biomass energy and electricity. When applying biomass energy and electricity, there are still some technical problems: when using biomass as an alternative fuel in a cement kiln (decomposition furnace), since biomass contains more chloride ions, in order to control the chloride ion content of cement clinker, the decomposition furnace bypass wind protection method is currently mainly used to release the raw materials with chloride ions together with the hot air. However, this method not only affects the thermal system of the decomposition furnace, but also causes a huge waste of energy because the released heat energy cannot be fully utilized. Utility Model Content
[0003] The utility model aims to provide a cement production system coupled with biomass energy, so as to solve the technical problem that when the prior art uses biomass as an alternative energy source, the chlorine content in cement clinker is high due to the presence of more chloride ions in the biomass ash.
[0004] The cement production system coupled with biomass energy comprises a rotary kiln, a decomposition furnace, a preheater and a chimney, wherein the kiln tail of the rotary kiln is connected below the decomposition furnace, the decomposition furnace is connected to the discharge port of the preheater, and the feed port of the preheater is connected to the raw material storage. The cement production system also comprises a biomass supply module and a gasifier, wherein the biomass supply module is used to supply biomass fuel to the first feed port of the gasifier, a feed branch pipe is provided in the feed pipeline connected between the preheater and the decomposition furnace, the second feed port of the gasifier is connected to the feed branch pipe, and the gas outlet at the top of the gasifier is connected to the decomposition furnace through a gas pipeline.
[0005] Preferably, the gasifier is a plasma gasifier, and a plasma torch extending inwardly is installed on the side wall above the slag discharge port at the lower part of the plasma gasifier.
[0006] Preferably, the biomass supply module includes a biomass supply bin, a conveying device 1, a drying device and a conveying device 2, the discharge port of the biomass supply bin is connected to the feed port of the drying device via the conveying device 1, and the discharge port of the drying device is connected to the first feed port of the gasifier via the conveying device 2.
[0007] Preferably, the drying device is a waste heat drying device that uses low-temperature hot air from a kiln head as a heating medium to heat the internal biomass, the kiln head of the rotary kiln is connected to the hot air inlet of the drying device through a hot air pipeline, the hot air outlet of the drying device is connected to a gas purification device through a pipeline, and the flue gas evolution device is connected to the chimney through a pipeline.
[0008] Preferably, the tail end of the plasma torch is connected to a gas supply pipe, an atomizing nozzle extending inwardly is installed on the side wall of the gas supply pipe, and the air inlet of the gas supply pipe is connected to the tail gas outlet at the tail of the rotary kiln through a pipeline.
[0009] Preferably, the plasma torch comprises a normally-on plasma torch and a standby plasma torch.
[0010] The utility model has the following advantages: the utility model can gasify biomass into CO, H 2 The gases are synthesized to form syngas fuel, which is sent to the decomposition furnace to replace part of the fuel in the cement production system. Since the hot raw meal is added from the decomposition furnace in the gasification furnace, the hot raw meal can react with chloride ions during the gasification process to solidify the chloride ions into the residue in the furnace, which has the effect of removing chlorine; and the residue produced by the gasification furnace is added to the cement as a mixed material under the premise of ensuring the chloride ion content of the cement product. The hot raw meal produced by the preheater has a relatively high temperature. The raw meal added to the gasification furnace has been preheated by the preheater, so it can reduce the energy consumption of the gasification furnace. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 The utility model is a structural schematic diagram of a cement production system coupled with biomass energy.
[0012] Figure 2 It is a schematic diagram of the flow chart of the utility model when it is running.
[0013] Figure 3 for Figure 1 Schematic diagram of the structure of the plasma torch in the shown structure.
[0014] The reference numerals in the accompanying drawings are as follows: 1-biomass supply bin; 2-drying device; 3-plasma gasifier; 4-plasma torch; 41-air inlet; 42-gas supply pipeline; 43-atomizing nozzle; 5-decomposition furnace; 6-rotary kiln; 7-preheater; 8-gas purification device; 9-chimney. DETAILED DESCRIPTION
[0015] The specific implementation methods of the utility model are further explained in detail below by describing the embodiments with reference to the accompanying drawings, so as to help those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the utility model.
[0016] like Figure 1-Figure 3 As shown, the utility model provides a cement production system coupled with biomass energy, including a rotary kiln 6, a decomposition furnace 5, a preheater 7 and a chimney 9, the kiln tail of the rotary kiln 6 is connected below the decomposition furnace 5, the decomposition furnace 5 is connected to the discharge port of the preheater 7, the feed port of the preheater 7 is connected to the raw material storage, the kiln head tail gas of the rotary kiln 6 is connected to the chimney 9 through the kiln head pipeline, the cement production system also includes a biomass supply module and a gasifier, the biomass supply module is used to supply biomass fuel to the first feed port of the gasifier, a feed branch pipe is provided in the feed pipeline connected between the preheater 7 and the decomposition furnace 5, the second feed port of the gasifier is connected to the feed branch pipe, and the gas outlet at the top of the gasifier is connected to the decomposition furnace 5 through a gas pipeline.
[0017] Traditional resistance heating has been applied in some industries such as ceramic sintering, but the temperature of resistance heating is relatively low and cannot meet the requirements of the cement industry (greater than 860°C). Arc thermal plasma technology has concentrated energy, high core temperature and short electrode life. Direct application in the decomposition furnace 5 is likely to cause local high-temperature crusting in the decomposition furnace 5 and cannot meet the requirements of continuous and stable industrial production. In this solution, the gasification furnace adopts a plasma gasification furnace 3, and a plasma torch 4 extending inward is installed on the side wall above the slag discharge port at the bottom of the plasma gasification furnace 3. In this way, this solution utilizes the high temperature and high enthalpy characteristics of plasma to efficiently gasify biomass into small molecules such as CO and H 2 And other flammable gases.
[0018] The biomass supply module includes a biomass supply bin 1, a conveying device 1, a drying device 2 and a conveying device 2. The drying device 2 is a waste heat drying device 2 that uses low-temperature hot air from a kiln head as a heating medium to heat the biomass inside. The discharge port of the biomass supply bin 1 is connected to the feed port of the drying device 2 through the conveying device 1, and the discharge port of the drying device 2 is connected to the first feed port of the gasifier through the conveying device 2. The kiln head of the rotary kiln 6 is connected to the hot air inlet of the drying device 2 through a hot air pipeline 1. The hot air outlet of the drying device 2 is connected to the gas purification device 8 through a pipeline, and the flue gas evolution device is connected to the chimney 9 through a pipeline. In this way, this solution can use the low-temperature hot air from the kiln head, which has a relative temperature lower than that of the kiln tail, to dry the biomass, effectively utilizing the waste heat resources of the cement kiln and saving energy consumption. The dried biomass can reduce the impact on the gasifier and reduce energy consumption.
[0019] The tail end of the plasma torch 4 is connected to a gas supply pipe 42, and a nozzle extending inward and passing water is installed on the side wall of the gas supply pipe 42. The nozzle is an atomizing nozzle 43, which sprays water into the gas supply pipe 42 in the form of atomized droplets. The air inlet 41 of the gas supply pipe 42 is connected to the tail gas outlet of the rotary kiln 6 through a pipeline. In order to fully gasify the biomass in the gasifier, it is generally an oxygen-deficient environment. It is conventional to use pure water vapor as the carrier gas of the plasma gasifier 3. In order to be more deeply coupled with cement production, the gas supply pipe 42 and the atomizing nozzle 43 should be arranged in the pipeline at the same time. By spraying water droplets, on the one hand, the oxygen content is further reduced, and on the other hand, the purpose of cooling the flue gas and protecting the plasma electrode is achieved.
[0020] The arrangement structure of the plasma torch 4 includes arranging 8 plasma torches 4 on the same plane of the plasma gasification furnace 3, of which four are normally open and the other four are standby. When the electrode of a plasma torch 4 needs to be replaced, the standby plasma torch 4 is started to ensure the continuous operation of the system. The preheater 7 adopts a five-stage suspension preheater 7, in which a part of the hot raw material output by the preheater 7C5 (i.e., the fifth-stage cyclone preheater 7) is separated by the feeding branch pipe and sent to the plasma gasification furnace 3 to be used as a dechlorination agent.
[0021] The working process of this scheme is as follows: after the system is in operation, the biomass material is unloaded from the biomass supply bin 1 and transported to the drying device 2. The biomass is mainly straw, rice husk, etc. When the system is in operation, the low-temperature hot air (temperature is about 100°C) generated by the rotary kiln 6 is transported to the drying device 2 through the pipeline to dry the biomass; at the same time, the preheater 7 feeds the hot raw material through the feeding branch pipe, and the biomass and the hot raw material are both introduced into the gasifier from the top. The gasifier uses the high temperature and high enthalpy characteristics of plasma to gasify the biomass into small molecules, producing CO, H 2 The synthesized syngas fuel is then sent to the calciner 5 through the gas pipeline for combustion; the slag discharge port is opened regularly to discharge the residue, which is added to the cement as a mixed material. The syngas fuel is input into the calciner 5 to replace part of the fuel in the cement production system.
[0022] The utility model is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the utility model is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the inventive concept and technical solution of the utility model, or the inventive concept and technical solution are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.
Claims
1. A cement production system coupled with biomass energy, comprising a rotary kiln (6), a decomposition furnace (5), a preheater (7) and a chimney (9), wherein the kiln tail of the rotary kiln (6) is connected below the decomposition furnace (5), the decomposition furnace (5) is connected to the discharge port of the preheater (7), and the feed port of the preheater (7) is connected to a raw material storage, characterized in that: It also includes a biomass supply module and a gasifier, wherein the biomass supply module is used to supply biomass fuel to the first feed port of the gasifier, a feed branch pipe is provided in the feed pipeline connected between the preheater (7) and the decomposition furnace (5), the second feed port of the gasifier is connected to the feed branch pipe, and the gas outlet at the top of the gasifier is connected to the decomposition furnace (5) through a gas pipeline.
2. A cement production system coupled with biomass energy according to claim 1, characterized in that: The gasification furnace is a plasma gasification furnace (3), and a plasma torch (4) extending inwardly is installed on the side wall above the slag discharge port at the lower part of the plasma gasification furnace (3).
3. A cement production system coupled with biomass energy according to claim 1 or 2, characterized in that: The biomass supply module comprises a biomass supply bin (1), a conveying device 1, a drying device (2) and a conveying device 2, wherein the discharge port of the biomass supply bin (1) is connected to the feed port of the drying device (2) via the conveying device 1, and the discharge port of the drying device (2) is connected to the first feed port of the gasifier via the conveying device 2.
4. A cement production system coupled with biomass energy according to claim 3, characterized in that: The drying device (2) is a waste heat drying device (2) that uses low-temperature hot air from a kiln head as a heating medium to heat the biomass inside. The kiln head of the rotary kiln (6) is connected to the hot air inlet of the drying device (2) through a hot air pipeline. The hot air outlet of the drying device (2) is connected to a gas purification device (8) through a pipeline. The gas purification device (8) is connected to the chimney (9) through a pipeline.
5. A cement production system coupled with biomass energy according to claim 2, characterized in that: The tail end of the plasma torch (4) is connected to a gas supply pipe (42), and an inwardly extending atomizing nozzle (43) is installed on the side wall of the gas supply pipe (42). The gas inlet (41) of the gas supply pipe (42) is connected to the tail gas outlet at the tail of the rotary kiln (6) through a pipeline.
6. A cement production system coupled with biomass energy according to claim 5, characterized in that: The plasma torch (4) includes a normally-on plasma torch and a standby plasma torch.