CN103157652B - Method for preparing desulfurizer from solid waste generated in soda ash plant industry - Google Patents
Method for preparing desulfurizer from solid waste generated in soda ash plant industry Download PDFInfo
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- CN103157652B CN103157652B CN201310121724.7A CN201310121724A CN103157652B CN 103157652 B CN103157652 B CN 103157652B CN 201310121724 A CN201310121724 A CN 201310121724A CN 103157652 B CN103157652 B CN 103157652B
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Abstract
The invention discloses a method for preparing a desulfurizer from solid waste generated in soda ash plant industry, which comprises the following steps: (1) mixing: evenly mixing return stone, return sand and gravel; (2) impurity removal: discharging the mixed material into a feed hopper, removing dust, discharging to a delivery belt, and removing impurities on the belt; (3) drying: delivering the material into a drying oven provided with a pulse dust remover through the belt, and carrying out drying and dust removal on the material; (4) crushing: delivering the material discharged from the drying oven into a crusher through the belt, and crushing; and (5) grinding: delivering the crushed material to a ball grinder, grinding in the ball grinder, selecting powder, and sending into a finished product bin. The invention has the advantages of simple technical process and low energy consumption, can be used for preparing the high-quality limestone powder desulfurizer with high CaO purity, high activity and fewer impurities, changes wastes into valuable substances, and greatly lowers the production cost.
Description
Technical field
The present invention relates to the solid waste comprehensive utilization produced in the industry of ammonia alkali legal system Sodium Carbonate Plant, particularly a kind of solid waste produced in Sodium Carbonate Plant industry that utilizes is to produce the method for fat lime stone flour desulfurizing agent.
Background technology
Soda ash is maximum, the purposes key industry raw material widely of output in basic chemical industry.China is the maximum soda manufacture state of global production capacity, is also the soda manufacture state that the whole world uniquely has connection alkali, ammonia alkali, trona three kinds of ripe production technologies.At present, China's soda ash annual production, up to 2,400 ten thousand tons, accounts for more than 40% of global soda ash output.Ammonia alkali, natural soda purification device are then obviously subject to the restriction of the aspects such as resource, region and environmental protection, trona technique is exactly the production technology of ammonia alkali legal system soda ash in itself, need input in environmental protection larger, quite a few alkali factory only discharges the discarded object produced in production process and does not process, and causes the destruction of natural environment very serious.Therefore, in the production process of ammonia-soda process, trona method preparing soda, how " three wastes " are effectively processed and remain a difficult problem, become the bottleneck of restriction enterprise development.
In prior art, when utilizing ammonia-soda process soda ash, mainly can produce three kinds of solid waste: sand return, return stone and rubble.That to be lime stone do not change into emulsion itself and particle through calcining is less in sand return, after sand return quarrel out, directly catches with automobile, walks and be finally put into stockyard.Returning stone is that the calcining of lime stone process does not change into emulsion and particle is larger, after returning stone quarrel out, directly catches with automobile, is finally put into stockyard.Rubble is stone through screening, and particle does not reach requirement, directly transports to stockyard with automobile.
Generally, often producing 1 ton of soda ash needs 1.4 tons of lime stones, can produce 50 kilograms and return stone, 30 kilograms of sand returns and 90 kilograms of rubbles.Limestone resource utilization rate is 88%, and discarded rate is 12%.The Sodium Carbonate Plant sand return of middle and small scale, the annual production returning stone and rubble can reach more than 90,000 tons, and after accumulation over the years, amount is big well imagines for it.In addition, being equivalent to process these discarded objects with the cost of purchase 12% lime stone for piling fortune, wasting a large amount of manpower and financial resources.Such as, the Sodium Carbonate Plant of middle and small scale is generally had an appointment 20 mu of large stockyards, sand return, returns stone and rubble puts into stockyard, if near have building site to want landfill, then spend freight charges to transport to building site.Near stockyard, dust flies upward all over the sky and waves, and environmental pollution is serious, all can not plant in several kilometers.
Energy-saving and emission-reduction, cleaner production are the needs of social development, are also the requirements of industry sustainable development.Along with Environmental Protection in China regulation is more and more stricter, these sand returns, return stone and rubble owing to can not get sufficient disposal and utilization, long-term stacking is unpractical, eventually must process it, and more late processing cost is higher.Sand return, return stone, the heap freight charges of rubble, land occupation resource expense and handling and must cause the raising of alkali factory integrated cost, but also environmental protection may be caused not pass a test.
At present, for sand return in ammonia-soda process soda ash process, the comprehensive utilizating research returning stone and rubble, domestic and international rarely found report, main cause is waste gas, waste liquid and alkaline residue etc. that its contaminative, harmfulness are discharged far below alkali factory, and for a long time, these solid waste are always for pave the way or as shaft kiln cement raw material etc., although value is very low, major part still can be consumed.And along with the pay attention to day by day of socialization environmental protection, to the raising of road quality level requirement and eliminating of shaft kiln cement plant, the above-mentioned solid waste consumption rate that alkali factory produces declines greatly, therefore, seek new utilization ways imperative.
Summary of the invention
The object of this invention is to provide the method that the solid waste produced in a kind of Sodium Carbonate Plant industry manufactures desulfurizing agent, technological process is simple, and energy consumption is low, can produce the fat lime stone flour desulfurizing agent that CaO purity is high, activity is high, impurity is few, turn waste into wealth, greatly reduce production cost.
Technical scheme of the present invention is: the solid waste produced in a kind of Sodium Carbonate Plant industry manufactures the method for desulfurizing agent, comprises concrete steps as follows:
(1) mix: stone, sand return, rubble Homogeneous phase mixing will be returned;
(2) removal of impurity: mixed material is discharged into feed hopper, after dedusting, blanking is to belt conveyor, and carries out Impurity removal on belt, wherein, dust removal process is undertaken by bag-type dust collector, and dedoping step removes metal garbage by powerful magnet;
(3) dry: by material by Belt Conveying in the drying oven being provided with pulsed dust-removing device, material is dried and dedusting, when the Temperature displaying of drying oven is 300 degree, the blower fan of starting impulse dust arrester configuration, is transferred to frequency converter display " 500 " by rotation speed of fan; When the Temperature displaying of drying oven is 500 degree, rotation speed of fan is transferred to running between frequency converter display " 1050 ~ 1200 ", now, starts charging;
(4) broken: from drying oven material out again through Belt Conveying in disintegrating machine, carry out fragmentation;
(5) grind: the mass transport after fragmentation to ball mill, and enters finished bin after selecting powder by ball mill grinding.
In step of the present invention (3), when material is dried in drying oven, the dust kicked up in drying course gathers dust process by pulsed dust-removing device automatically, and dust collection powder directly enters finished bin through elevator.
In step of the present invention (4), from drying oven material out, belt conveyor removes metal garbage further by powerful magnet, then enters disintegrating machine.
In step of the present invention (4), material enters disintegrating machine and carries out one-level fragmentation, is broken into the particle of less than a centimeter, then enters semi-finished product storehouse through semi-finished product lifter.
In step of the present invention (5), the material after fragmentation is delivered to ball mill through elevator, enters the material of ball mill after grinding, selection by winnowing 100 order ~ 325 object product introduction finished bin; After selection by winnowing, underproof product comes back to ball mill and grinds.
The invention has the beneficial effects as follows:
(1) the present invention be produce in ammonia alkali legal system soda ash process sand return, return stone, these three kinds of solid waste of rubble have found practicable new utilization ways, combine the technology such as oven dry, dedusting and grinding, fat lime stone flour desulfurizing agent can be produced, technological process is simple, with low cost, energy-conserving and environment-protective, are applicable to large-scale production application;
The sand return produced in Sodium Carbonate Plant industrial processes, return stone and rubble forms primarily of CaCO3, Ca (OH) 2, burning CaO, high-temperature calcination generates CaO, wherein sand return, return Shi Zhongyue containing 30% Ca (OH) 2.CaO > 52% in material; MgO < 2%; SiO2 < 1%; The equal < 1% of Al2O3 and Fe2O3, can substitute agstone in theory completely and be used as boiler flue gas desulfurization agent.Above-mentioned three kinds of solid waste are applied to boiler flue gas desulfurization, not only meet current country-driven energy-saving and emission-reduction requirement, also meet the inevitable requirement that enterprise realizes cleaner production, sustainable development simultaneously, and can turn waste into wealth, achieve resource 100% to utilize, thus saved other natural resources or raw material in short supply, and decrease and need exploitation more limestone mines and to the destruction of ecological environment and the consumption of the energy.Desulfurizing agent is used for power plant, has not only widened the scope of available resources (can raw material be utilized), and reduced production cost.Therefore, the present invention can obtain many-sided social benefit, very meaningful.
After integrated treatment being carried out to three kinds of solid waste by the present invention, the little stockyard of one 500 squares is established in alkali factory, produce in soda ash process processed return stone, sand return, rubble be put into inside little stockyard, spray with water, allow sand return, return stone and fully absorb moisture, substantially solve dirt problems, reduce the pollution to environment.Loaded onto ship by dumper again, transport to the factory floor manufacturing desulfurizing agent.Present invention effectively prevents long-term stacking and the accumulation of solid waste, save land resource.
(2) the desulfurizing agent products C aO purity produced through the present invention is high, active high (containing part Ca (OH) 2), and impurity is few, reaches the standard of the high-quality desulfurized limestone powder that power plant uses completely, can be directly used in environment protection desulphurization.Utilize desulfurizing agent desulfuration efficiency of the present invention to be greater than 95%, accessory substance gypsum purity is greater than 85%.
The standard of the fat lime powder desulfurizing agent produced by the present invention is: CaO > 52%; MgO < 2%; SiO2 < 1%; 325 order percent of pass >=90% (can according to the needs of user, adjustment order number).
(3) raw material sources are easy, and " treatment of wastes with processes of wastes against one another ", belongs to " recycling economy " category, and the desulfurized limestone powder price that the present invention produces has obvious competitive advantage, meets country's " recycling economy " theory.
Accompanying drawing explanation
Fig. 1 is the process chart that the solid waste produced in Sodium Carbonate Plant industry manufactures desulfurizing agent.
Detailed description of the invention
Below in conjunction with accompanying drawing, the invention will be further described.
Embodiment 1
As shown in Figure 1, the solid waste produced in a kind of Sodium Carbonate Plant industry manufactures the method for desulfurizing agent to one of the specific embodiment of the present invention, comprises concrete steps as follows:
(1) mix: stone, sand return, rubble Homogeneous phase mixing will be returned; Return stone, sand return, rubble concrete ratio can determine according to actual conditions, mix.
In the present embodiment, be specially: in special place, with forklift by returning stone, sand return, rubble mix according to the ratio uniform of 1.6:1:3.2.
(2) removal of impurity: mixed material is discharged into feed hopper, and blanking is to belt conveyor after dedusting, and Impurity removal is carried out on belt;
(3) dry: by material by Belt Conveying in the drying oven being provided with pulsed dust-removing device, material is dried and dedusting;
(4) broken: from drying oven material out again through Belt Conveying in disintegrating machine, carry out fragmentation;
(5) grind: the mass transport after fragmentation to ball mill, and enters finished bin after selecting powder by ball mill grinding.
In the step (2) of the present embodiment, six groups of powerful magnets are housed above belt conveyor, with forklift, the material mixed is discharged into feed hopper, first mixed material carries out dedusting by bag-type dust collector, then enter first, second and third by Belt Conveying and organize powerful magnet, remove most of metal garbage.
In the step (3) of the present embodiment, when the Temperature displaying of drying oven is 300 degree, the blower fan of starting impulse dust arrester configuration, is transferred to frequency converter display " 500 ", now can't starts charging by rotation speed of fan; When the Temperature displaying of drying oven is 500 degree, rotation speed of fan is transferred to frequency converter display " 1050 " running, now, starts charging.
In step (3), when material is dried in drying oven, pulsed dust-removing device starts, and process (major part is calcium hydroxide) of automatically being gathered dust by the dust kicked up in drying course, dust collection powder directly enters finished bin through elevator.
In step (4), from drying oven material out, enter fourth, fifth, six groups of powerful magnets by belt conveyor, namely remove metal garbage further by powerful magnet, and then enter disintegrating machine.
In step (4), material enters disintegrating machine and carries out one-level fragmentation, is broken into the particle that particle diameter is less than a centimeter, then enters semi-finished product storehouse through semi-finished product lifter.
In step (5), the material after fragmentation is delivered to ball mill through elevator, and enter the material of ball mill after grinding, selection by winnowing 100 object product introduction finished bin, finished bin is also specially provided with bag-type dust collector; After selection by winnowing, underproof product comes back to ball mill and grinds.The particle size of finished product can set flexibly according to the requirement of particular user.
Finally, product in finished bin, loads agstone groove tank car and is transported to user after sample examination is qualified.
Embodiment 2
The specific embodiment of the present invention two as shown in Figure 1, with a upper embodiment difference be, in step (1), return stone, sand return, rubble ratio be 1.5:1:2.In step (3), when the Temperature displaying of drying oven is 500 degree, rotation speed of fan is transferred to frequency converter display " 1125 " running, now, starts charging.In step (5), the material after fragmentation is delivered to ball mill through elevator, enters the material of ball mill after grinding, selection by winnowing 220 object product introduction finished bin.
Embodiment 3
The specific embodiment of the present invention three as shown in Figure 1, with embodiment 1 difference be, in step (1), return stone, sand return, rubble ratio be 1:1:1.In step (3), when the Temperature displaying of drying oven is 500 degree, rotation speed of fan is transferred to frequency converter display " 1200 " running, now, starts charging.In step (5), the material after fragmentation is delivered to ball mill through elevator, enters the material of ball mill after grinding, selection by winnowing 325 object product introduction finished bin.
Experimental example
Certain power plant employs the desulfurizing agent produced according to present invention process.
Table 1: this power plant desulphurization system uses agstone standard
| Project | Unit | Require parameter | Remarks |
| CaO | Wt－％ | ≥50 | —— |
| SiO 2 | Wt－％ | ≤0.27 | —— |
| Al 2O 3 | Wt－％ | ≤0.3 | —— |
| Fe 2O 3 | Wt－％ | ≤0.16 | —— |
| MgO | Wt－％ | ≤1.63 | —— |
| SO 3 | Wt－％ | 0.13～0.14 | —— |
| Grindability index HGI | 43 | —— | |
| Particle diameter | μm | 44 | Sieving rate 90% |
| Table moisture content | Wt－％ | ≤1 | —— |
Table 2: the desulfurizing agent testing result that this power plant produces the present invention
The desulfurizing agent that this power plant desulphurization system uses the present invention to produce, desulfuration efficiency is 96.21%, completely up to standard.
Table 3: neat stress parameter
| Flue gas flow | 124.6 ten thousand m 3/h |
| Chimney inlet pressure | -73.09Pa |
| Flue-gas temperature | -2.0℃ |
| NO XConcentration | 51.9mg/m 3 |
| O 2Concentration | 7.46％ |
| SO 2Concentration | 44.7mg/m 3 |
| H 2O concentration | 2.04％ |
| CO 2Concentration | 5.1％ |
| CO concentration | 30.0mg/m 3 |
| DUST concentration | 12.7mg/m 3 |
The desulfurated plaster of desulfurizing agent (agstone) output that the desulphurization system of this power plant uses the present invention to produce reaches the GB175-2007 national standard that cement plant uses completely.
Table 4: desulfurated plaster detected parameters
In addition, certain paper mill also using the desulfurizing agent that present invention process is produced, and desulfuration efficiency is completely up to standard.
The above embodiments are only the preferred embodiments of the present invention, can not limit interest field of the present invention with this, and therefore, the equivalent variations done according to the present patent application the scope of the claims, still belongs to the scope that the present invention is contained.
Claims (5)
1. the solid waste produced in Sodium Carbonate Plant industry manufactures a method for desulfurizing agent, it is characterized in that comprising concrete steps as follows:
(1) mix: stone, sand return, rubble Homogeneous phase mixing will be returned;
(2) removal of impurity: mixed material is discharged into feed hopper, after dedusting, blanking is to belt conveyor, and carries out Impurity removal on belt, wherein, dust removal process is undertaken by bag-type dust collector, and dedoping step removes metal garbage by powerful magnet;
(3) dry: by material by Belt Conveying in the drying oven being provided with pulsed dust-removing device, material is dried and dedusting, when the Temperature displaying of drying oven is 300 degree, the blower fan of starting impulse dust arrester configuration, is transferred to frequency converter display " 500 " by rotation speed of fan; When the Temperature displaying of drying oven is 500 degree, rotation speed of fan is transferred to running between frequency converter display " 1050 ~ 1200 ", now, starts charging;
(4) broken: from drying oven material out again through Belt Conveying in disintegrating machine, carry out fragmentation;
(5) grind: the mass transport after fragmentation to ball mill, and enters finished bin after selecting powder by ball mill grinding.
2. the solid waste produced in a kind of Sodium Carbonate Plant industry according to claim 1 manufactures the method for desulfurizing agent, it is characterized in that in described step (3), when material is dried in drying oven, the dust kicked up in drying course gathers dust process by pulsed dust-removing device automatically, and dust collection powder directly enters finished bin through elevator.
3. the solid waste produced in a kind of Sodium Carbonate Plant industry according to claim 2 manufactures the method for desulfurizing agent, it is characterized in that in described step (4), from drying oven material out, belt conveyor removes metal garbage further by powerful magnet, then enters disintegrating machine.
4. the solid waste produced in a kind of Sodium Carbonate Plant industry according to claim 3 manufactures the method for desulfurizing agent, it is characterized in that in described step (4), material enters disintegrating machine and carries out one-level fragmentation, be broken into the particle of less than a centimeter, then entered semi-finished product storehouse through semi-finished product lifter.
5. the solid waste produced in a kind of Sodium Carbonate Plant industry according to claim 4 manufactures the method for desulfurizing agent, it is characterized in that in described step (5), material after fragmentation is delivered to ball mill through elevator, enter the material of ball mill after grinding, selection by winnowing 100 order ~ 325 object product introduction finished bin; After selection by winnowing, underproof product comes back to ball mill and grinds.
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104190690B (en) * | 2014-08-06 | 2016-05-04 | 华南理工大学 | A kind of method and application that utilizes ammonia-soda process alkaline residue to prepare dechlorination alkaline residue mixture |
| CN111977993B (en) * | 2019-05-21 | 2022-04-12 | 江苏苏盐井神股份有限公司 | Device and method for performing desulfurization or ash melting on returned stone and returned sand pulping in soda production |
| CN111454003A (en) * | 2020-04-29 | 2020-07-28 | 山东海天生物化工有限公司 | Method for recycling return sand in soda production |
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