System for producing lime from carbide slag
By treating carbide slag with cyclone preheating and suspension calcination technology to produce lime and return it to the carbide production line, the problems of low utilization rate and environmental pollution of carbide slag are solved, realizing efficient and low-carbon resource recycling and improving the economic benefits of enterprises.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2026-04-03
AI Technical Summary
The utilization rate of calcium carbide slag is low, long-term stockpiling leads to environmental pollution and poses safety hazards. Existing processes have high energy consumption and high costs, resulting in poor market competitiveness.
The calcium carbide slag is treated using cyclone preheating, suspension calcination and suspension cooling technologies to prepare lime, which is then returned to the calcium carbide production line as raw material. Calcium carbide by-products are used as fuel to achieve continuous production and efficient utilization.
This has enabled the efficient resource utilization of carbide slag, reduced energy consumption and production costs, reduced environmental pollution, met the goals of low-carbon and environmental protection, and improved the economic benefits of enterprises.
Smart Images
Figure CN224077261U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of industrial waste recycling technology, specifically relating to a system for producing lime from carbide slag. Background Technology
[0002] Calcium carbide slag is an industrial waste residue mainly composed of calcium hydroxide, produced after the hydrolysis of calcium carbide to obtain acetylene. Calcium carbide is widely used in industry, including organic synthesis, oxyacetylene welding, and steel desulfurization, and is an important raw material for PVC production.
[0003] Currently, using calcium carbide slag as a raw material for cement production is the main way to comprehensively utilize it. However, calcium carbide slag cement production is complex, energy-intensive, requires large investments, has low output, and lacks market competitiveness. Calcium carbide slag can also be directly used in construction projects to prepare lime mortar for use in the three-component soil of highway subgrades, but its high water content leads to high transportation costs and dispersed usage points, limiting its application and potentially causing new environmental pollution. Calcium carbide slag can also be used in environmental protection fields such as wastewater treatment, soil improvement, and flue gas desulfurization, but many technologies and methods are still immature, limiting its application. Calcium carbide slag can be used to produce lime, high-whiteness ultrafine calcium carbonate, coatings, and other chemical products, but the presence of impurities in the slag results in low product quality, high production costs, and poor economic benefits. Large quantities of calcium carbide slag cannot be utilized as a resource, so most companies choose to dump or landfill it on-site.
[0004] Calcium carbide slag is classified as Class II general industrial solid waste. Its highly alkaline leachate can pollute soil and water bodies, and long-term stockpiling can lead to serious environmental pollution. The flammable and explosive gases in calcium carbide slag are prone to explosion when exposed to ignition sources or high temperatures, causing personal injury and environmental hazards. In addition, the heavy metals and organic substances in calcium carbide slag also pose certain risks to the environment and human health.
[0005] Carbide slag is an industrial waste that must be taken seriously and given priority in treatment and utilization. Only by seeking breakthroughs in process technology can carbide slag be transformed from waste into treasure and promote the green and sustainable development of the carbide industry.
[0006] Therefore, based on the above problems, this utility model provides a system for producing lime from carbide slag. Utility Model Content
[0007] Purpose of the utility model: The purpose of this utility model is to provide a lime production system from carbide slag to solve the problems of limited use of carbide slag, long-term stockpiling, and environmental pollution, and to enable the efficient and comprehensive utilization of carbide slag.
[0008] Technical solution: This utility model provides a lime production system from carbide slag. The system consists of a carbide slag silo, metering equipment, conveying equipment A, conveying equipment B, conveying equipment C, conveying equipment D, homogenization metering system, cyclone preheating system, cyclone calcination and decomposition system, suspension cooling system, lime silo, granulation equipment, and a carbide production line.
[0009] The calcium carbide slag powder in the calcium carbide slag storage is metered by a metering device and then sent to the cyclone preheating system via conveying device B.
[0010] The cyclone preheating system preheats and removes impurities from the calcium carbide slag powder.
[0011] The purified and preheated carbide slag powder is sent to a cyclone calcination and decomposition system for calcination and decomposition.
[0012] The calcined and decomposed lime product is sent to a suspension cooling system for cooling and collection.
[0013] The finished lime collected by the cyclone cooling system is sent to the lime silo for storage via conveyor C;
[0014] The lime powder coming out of the bottom of the lime silo is measured by the homogenization and metering system and then sent to the granulation equipment by the conveying equipment D.
[0015] The granulation equipment extrudes and granulates lime.
[0016] The prepared granular calcium oxide is connected to the existing calcium carbide production line in the plant and used as a raw material for calcium carbide production.
[0017] In this technical solution, the carbide slag silo is connected to a metering device; the metering device is connected to one end of the conveying device B; the other end of the conveying device B is connected to a cyclone preheating system; wherein, the metering device is a quantitative feeder; and the conveying device B is a belt conveyor and a bucket elevator.
[0018] In this technical solution, the cyclone preheating system in step 2 includes a drying and dispersing machine, a powder classifier and slag remover, and a bag filter. The cyclone preheating system is connected to the bag filter. The exhaust gas from the cyclone preheating system is purified by the bag filter before being discharged. The particles collected by the bag filter are undecomposed calcium hydroxide, which are sent to the kiln ash silo and then fed back into the furnace for calcination via conveying equipment A. The calcium carbide slag powder conveyed by conveying equipment B is first processed by the drying and dispersing machine and then further processed by the powder classifier and slag remover.
[0019] In this technical solution, the cyclone calcination and decomposition system in step 3 includes a decomposition furnace and a cyclone separator. The decomposition furnace is connected to the powder classifier and slag remover and the cyclone separator respectively. The calcium carbide slag powder that has been cleaned and preheated by the drying and dispersing machine, the powder classifier and slag remover and the bag dust collector is sent to the decomposition furnace for suspension calcination. The calcined and decomposed lime product enters the next stage cyclone separator for material-gas separation. The high-temperature waste gas enters the upper cyclone preheating system to dry and preheat the calcium carbide slag powder.
[0020] In this technical solution, the suspension cooling system in step 4 includes a suspension cooler, a high-temperature induced draft fan, a hot air combustion furnace, and an extraction and purification device. The suspension cooler adopts an air-cooled form, directly utilizing fresh air for rapid cooling. One end of the suspension cooler is connected to the high-temperature induced draft fan, and the other end is connected to a cyclone separator. One end of the high-temperature induced draft fan is connected to the hot air combustion furnace. The extraction and purification device is connected to the calcium carbide production line and the hot air combustion furnace, respectively. The hot air exiting the suspension cooler is heat recovered and reused, and then sent to the hot air combustion furnace by the high-temperature induced draft fan to provide the hot air required for combustion. The fuel for the hot air combustion furnace is carbon monoxide, a byproduct of calcium carbide production, which is sent to the furnace for combustion through pipelines via the carbon monoxide extraction and purification device.
[0021] In this technical solution, the conveying equipment C in step 5 includes, but is not limited to, an air conveying chute.
[0022] In this technical solution, the homogenization metering system is installed at the bottom of the lime silo.
[0023] In this technical solution, the conveying equipment D is an air conveying chute and a bucket elevator.
[0024] Compared with the prior art, the beneficial effects of the calcium carbide slag lime production system of this utility model are as follows:
[0025] 1. The process flow of this utility model is simple and the system layout is compact. It adopts the suspension preheating decomposition and calcination technology of cyclone preheating plus pipeline decomposition furnace plus suspension cooling, which can realize continuous production, high production efficiency, carbide slag decomposition rate greater than 98%, and high yield. The produced lime has good activity. This suspension calcination production technology is very advanced, efficient and environmentally friendly.
[0026] 2. This utility model adopts suspended calcination calcium carbide slag technology, which can reduce the energy consumption per unit of lime product, thereby reducing the energy consumption per unit of finished calcium carbide product. Moreover, the calcination fuel uses furnace gas, a by-product of calcium carbide, which can achieve the rational and full utilization of coal resources without additional coal resource consumption. The adoption of this technology will significantly reduce the energy cost of the product, which is in line with the energy conservation and consumption reduction development direction of the calcium carbide industry and brings greater economic benefits to enterprises.
[0027] 3. The calcination raw material of this utility model is industrial waste residue, which can basically realize the recycling of calcium compounds, achieve the goal of zero solid waste discharge, solve the problem of difficult treatment of industrial solid waste residue, reduce the environmental pollution caused by the dumping and burial of carbide slag and the treatment cost of solid waste, and has extremely high social and environmental benefits and corporate economic benefits.
[0028] 4. This utility model has greater environmental value than limestone calcination, which produces a large amount of carbon dioxide. It is a truly low-carbon production method that fully complies with low-carbon and environmental protection goals. It provides a way for enterprises to gain a dominant advantage in the carbon trading market and establish a benchmark image.
[0029] 5. This utility model adopts a pure dry production process, which does not produce production water or production wastewater, only a small amount of domestic water and cooling water; the cooling water does not come into direct contact with raw materials and products, but only serves as a heat exchange medium, and the water quality does not undergo chemical changes. Most of it can be recycled, and a small amount is directly discharged; the domestic wastewater does not contain harmful substances and can be directly discharged. Attached Figure Description
[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0031] Figure 1 This is a flowchart of a lime production system based on carbide slag, according to this utility model. Detailed Implementation
[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.
[0033] In the description of this utility model, it should be noted that the terms "top," "bottom," "one side," "the other side," "front," "back," "middle part," "inner," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "joined" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0034] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.
[0035] Example: Figure 1 The system shown is a lime production system using carbide slag. The system consists of a carbide slag silo, metering equipment, conveying equipment A, conveying equipment B, conveying equipment C, conveying equipment D, homogenization metering system, cyclone preheating system, cyclone calcination and decomposition system, suspension cooling system, lime silo, granulation equipment, and a carbide production line.
[0036] The calcium carbide slag powder in the calcium carbide slag storage is metered by a metering device and then sent to the cyclone preheating system via conveying device B.
[0037] The cyclone preheating system preheats and removes impurities from the calcium carbide slag powder.
[0038] The purified and preheated carbide slag powder is sent to a cyclone calcination and decomposition system for calcination and decomposition.
[0039] The calcined and decomposed lime product is sent to a suspension cooling system for cooling and collection.
[0040] The finished lime collected by the cyclone cooling system is sent to the lime silo for storage via conveyor C;
[0041] The lime powder coming out of the bottom of the lime silo is measured by the homogenization and metering system and then sent to the granulation equipment by the conveying equipment D.
[0042] The granulation equipment extrudes and granulates lime.
[0043] The prepared granular calcium oxide is connected to the existing calcium carbide production line in the plant and used as a raw material for calcium carbide production.
[0044] Preferably, the carbide slag silo is connected to a metering device; the metering device is connected to one end of the conveying device B; and the other end of the conveying device B is connected to a cyclone preheating system.
[0045] The metering device is a quantitative feeder; the conveying device B is a belt conveyor and a bucket elevator.
[0046] Preferably, the cyclone preheating system in step 2 includes a drying and dispersing machine, a powder classifier and slag remover, and a bag filter. The cyclone preheating system is connected to the bag filter. The exhaust gas from the cyclone preheating system is purified by the bag filter before being discharged. The particles collected by the bag filter are undecomposed calcium hydroxide, which are sent to the kiln ash silo and then fed back into the furnace for calcination via conveying equipment A.
[0047] Among them, the calcium carbide slag powder conveyed by conveyor B is first processed by a drying and dispersing machine and then enters a powder classifier and slag remover for further processing.
[0048] Preferably, the cyclone calcination and decomposition system in step 3 includes a decomposition furnace and a cyclone separator. The decomposition furnace is connected to the powder classifier and slag remover, and the cyclone separator, respectively. The calcium carbide slag powder that has been cleaned and preheated by the drying and dispersing machine, the powder classifier and slag remover, and the bag filter is sent to the decomposition furnace for suspension calcination. The calcined and decomposed lime product enters the next stage cyclone separator for material-gas separation. The high-temperature waste gas enters the upper cyclone preheating system to dry and preheat the calcium carbide slag powder.
[0049] Preferably, the suspension cooling system in step 4 includes a suspension cooler, a high-temperature induced draft fan, a hot air combustion furnace, and an extraction and purification device. The suspension cooler is air-cooled, directly utilizing fresh air for rapid cooling. One end of the suspension cooler is connected to the high-temperature induced draft fan, and the other end is connected to a cyclone separator. One end of the high-temperature induced draft fan is connected to the hot air combustion furnace. The extraction and purification device is connected to the calcium carbide production line and the hot air combustion furnace, respectively. The hot air exiting the suspension cooler is heat-recovered and reused, and then sent to the hot air combustion furnace by the high-temperature induced draft fan to provide the hot air required for combustion, making reasonable use of waste heat and reducing the heat consumption required to heat the air.
[0050] The fuel for the hot air combustion furnace is carbon monoxide, a byproduct of calcium carbide production in the calcium carbide production line. The carbon monoxide is extracted and purified by a carbon monoxide extraction and purification device and then piped into the furnace for combustion.
[0051] Alternatively, preferably, the conveying equipment C in step 5 includes, but is not limited to, an air conveying chute, to achieve rapid and safe conveying of carbide slag powder.
[0052] Alternatively, preferably, the homogenization metering system is installed at the bottom of the lime silo and is detachable for easy inspection and maintenance.
[0053] Alternatively, preferably, the conveying equipment D is an air conveying chute and a bucket elevator, which enables the rapid and safe conveying and lifting of calcium carbide slag powder.
[0054] In addition, the production process of the calcium carbide slag lime production system includes the following steps:
[0055] Step 1: The calcium carbide slag powder in the calcium carbide slag silo is metered by a metering device and then sent to the cyclone preheating system via conveyor B.
[0056] Step 2: The cyclone preheating system preheats and removes impurities from the calcium carbide slag powder.
[0057] Step 3: The preheated and impurity-removed calcium carbide slag powder is sent to the cyclone calcination and decomposition system for calcination and decomposition;
[0058] Step 4: The calcined and decomposed lime product is sent to a suspension cooling system for cooling and collection;
[0059] Step 5: The finished lime collected by the cyclone cooling system is sent to the lime silo for storage via conveyor C;
[0060] Step 6: The lime powder coming out of the bottom of the lime silo is measured by the homogenization and metering system and then sent to the granulation equipment through the conveying equipment D;
[0061] Step 7: The granulation equipment extrudes and granulates the lime; Step 8: The granulated calcium oxide is fed into the existing calcium carbide production line in the plant and used as a raw material for calcium carbide production.
[0062] Furthermore, preferably, the water content of the calcium carbide slag powder in step 1 is 6% or 7% or 8% or 9% or 10%; the removal of impurities from the calcium carbide slag in step 2 includes, but is not limited to, glass.
[0063] This invention utilizes advanced suspension preheating calcination and cooling technology to purify, calcine, and shape calcium carbide slag into granular calcium oxide, which is then returned to the calcium carbide furnace to produce calcium carbide, thus realizing the recycling of calcium oxide in the chlor-alkali industry.
[0064] It should be noted that, in this document, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0065] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
Claims
1. A calcium carbide slag to lime production system, characterized by: The calcium carbide slag warehouse, metering equipment, conveying equipment A, conveying equipment B, conveying equipment C, conveying equipment D, homogenization metering system, cyclone preheating system, cyclone calcination decomposition system, suspension cooling system, lime warehouse, granulation equipment and calcium carbide production line are connected. The calcium carbide slag powder in the calcium carbide slag warehouse is metered by the metering equipment and then sent to the cyclone preheating system by the conveying equipment B. The cyclone preheating system preheats and removes impurities from the calcium carbide slag powder. The calcium carbide slag powder is sent to the cyclone calcination decomposition system for calcination and decomposition. The calcined and decomposed lime product is sent to the suspension cooling system for cooling and collection. The lime product is sent to the lime warehouse for storage by the conveying equipment C. The lime product is metered and then sent to the granulation equipment for extrusion granulation by the conveying equipment D.
2. A calcium carbide slag to lime system according to claim 1, characterised in that: The calcium carbide slag warehouse is connected to the metering equipment; the metering equipment is connected to one end of the conveying equipment B; the other end of the conveying equipment B is connected to the cyclone preheating system. The metering equipment is a quantitative feeder; the conveying equipment B is a belt conveyor and a bucket elevator.
3. A calcium carbide sludge to lime system according to claim 2, characterized in that: The cyclone preheating system includes a drying and scattering machine, a powder selection and slag removal machine, and a bag-type dust collector; the cyclone preheating system is connected to the bag-type dust collector; the exhaust gas from the cyclone preheating system is purified by the bag-type dust collector and then discharged; the particles collected by the bag-type dust collector are undecomposed calcium hydroxide, which is sent to the kiln ash bin and then sent to the furnace for calcination again by the conveying equipment A. The calcium carbide slag powder conveyed by the conveying equipment B is first treated by the drying and scattering machine and then treated by the powder selection and slag removal machine.
4. A calcium carbide slag to lime system according to claim 3, wherein: The cyclone calcination decomposition system includes a decomposition furnace and a cyclone; the decomposition furnace is connected to the powder selection and slag removal machine and the cyclone, respectively. The calcium carbide slag powder treated by the drying and scattering machine, the powder selection and slag removal machine, and the bag-type dust collector is sent to the decomposition furnace for suspension calcination; the calcined and decomposed lime product enters the next-stage cyclone for material-gas separation; the high-temperature exhaust gas enters the upper cyclone preheating system to dry and preheat the calcium carbide slag powder.
5. A calcium carbide sludge to lime system according to claim 4, characterized in that: The suspension cooling system includes a suspension cooler, a high-temperature induced draft fan, a hot air combustion supplement furnace, and an extraction and purification device; the suspension cooler uses air cooling and directly uses fresh air for rapid cooling. One end of the suspension cooler is connected to the high-temperature induced draft fan; the other end of the suspension cooler is connected to the cyclone; one end of the high-temperature induced draft fan is connected to the hot air combustion supplement furnace; the extraction and purification device is connected to the calcium carbide production line and the hot air combustion supplement furnace, respectively. The hot air from the suspension cooler is recycled and used; it is sent to the hot air combustion supplement furnace by the high-temperature induced draft fan to provide hot air for combustion. The fuel of the hot air combustion supplement furnace is carbon monoxide, a byproduct produced during the production of calcium carbide by the calcium carbide production line; it is sent to the furnace by the carbon monoxide extraction and purification device through a pipeline.
6. A calcium carbide sludge to lime system according to claim 1, characterized in that: The conveying equipment C includes but is not limited to an air conveying chute.
7. A calcium carbide sludge to lime system according to claim 5, characterized in that: The homogenization metering system is installed at the bottom of the lime warehouse.
8. A calcium carbide sludge to lime system according to claim 1, characterized in that: The conveying equipment D is an air conveying chute and a bucket elevator.