CN1775660A - Method for producing sulfuric acid utilizing phosphogypsum slag - Google Patents
Method for producing sulfuric acid utilizing phosphogypsum slag Download PDFInfo
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- CN1775660A CN1775660A CN 200510022084 CN200510022084A CN1775660A CN 1775660 A CN1775660 A CN 1775660A CN 200510022084 CN200510022084 CN 200510022084 CN 200510022084 A CN200510022084 A CN 200510022084A CN 1775660 A CN1775660 A CN 1775660A
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Abstract
The invention is a method for making vitriol using phosphorus plaster with respect to the three-waste problem caused by the phosphorus plaster waste residues, in turn mixing, reductively baking, making double decomposition reaction, making absorption reaction, press filtering to make filter cake and baking to make sulfur, recovering and extracting sulfur ore resources from the phosphorus plaster waste residues to replace the sulfurous iron ore to act as raw material to produce vitriol product, achieving the purpose of turning waste into wealth. The invention solves the pollution problem of waste residues of puzzling long-time and restricting the development of phosphorus chemical industrial enterprises of our country. And the invention can largely reduce the production cost and has completely remarkable social and economic benefits.
Description
The technical field is as follows:
the invention relates to a technology for preparing sulfuric acid by recycling phosphogypsum waste residues discharged by phosphate industry, belongs to the technical field of three-waste treatment and chemical production in environmental protection, and particularly relates to a production method for preparing sulfuric acid by using the phosphogypsum waste residues.
Background art:
as we know, in the phosphate production industry, particularly, when series products such as wet-process phosphoric acid, phosphate and the like are produced by adopting phosphate ore and sulfuric acid, a large amount of phosphogypsum waste residues are generated, and the existing phosphate chemical industry enterprisesThe phosphogypsum waste residue is directly discharged and discarded as industrial waste residue, the discharge and accumulation are carried out day after day and year after year for a long time, vicious circle is formed, the discharged waste phosphogypsum waste residue is accumulated into a large mountain from a small mountain, and becomes a waste residue mountain environmental pollution which seriously threatens the surrounding ecological environment and is difficult to treat and solve so far, and the waste residue mountain formed by the phosphogypsum waste residue is a serious problem which troubles and restricts the generation and development of the phosphorus chemical industry in China so far, and how to change waste into valuable and develop and utilize the phosphogypsum waste residue is also a great technical problem which is urgently needed to be solved and difficult to be solved at any time by the environmental protection department in China at present. Through detection and determination: the main component in the phosphogypsum waste residue is calcium sulfate CaSO4It contains rich sulfur resource, and this phosphogypsum "waste residue hill" is the sulfur ore resource library required by chemical industry department for producing sulfuric acid product. Through years of development and research, the company successfully recycles the phosphogypsum waste residues discharged by phosphate chemical enterprises as raw materials to extract sulfur resources for producing sulfuric acid products, and achieves the purpose of recycling the phosphogypsum waste residues by changing waste into valuable, thereby solving the environmental protection problem which always restricts the generation and development of phosphorus chemical industrial enterprises in China. So far, the production technology for producing the sulfuric acid product by completely recycling the phosphogypsum waste residues discarded by phosphate chemical enterprises as the raw material has not been reported at home and abroad.
The invention content is as follows:
the invention is based on the existing chemical technology, especially to the problem that the three wastes caused by the waste residue of phosphogypsum that is discarded by phosphate chemical enterprises at present pollute, propose a recovery to utilize the waste residue of phosphogypsum to prepare the production method of the sulfuric acid, it is to extract the resource of pyrite from waste residue of phosphogypsum to replace pyrite to produce the sulfuric acid product, the invention is realized according to the following technical scheme:
the method comprises the following steps in sequence:
(1) metering and batching: the raw materials for the reaction are as follows by weight:
1 part of phosphogypsum waste residue,
0.15-0.35 portion of coal,
the weighed raw materials are sent into a crusher to be crushed to prepare a mixed material,
(2) reduction roasting: sending the prepared mixed material into a roasting furnace for reduction roasting reaction, controlling the temperature in the roasting furnace to be 800-1200 ℃, and carrying out the reduction roasting reaction for 10-20 minutes under the condition of stirring, wherein the reduction roasting reaction equation is as follows:
production of calcium sulfide CaS and carbon dioxide CO2The flow rate of the flue gas,
(3) double decomposition reaction: delivering the calcium sulfide CaS obtained by reduction roasting into a pulverizer for pulverizing, delivering into a reaction tank by water distribution 2-4 times of the weight of calcium sulfide, adding acetic acid CH3COOH (as catalyst in double decomposition reaction) to regulate and control pH value of liquid in reaction tank to 1-3, and then reducing and roasting to produce carbon dioxide CO2Inputting the flue gas into a reaction tank to perform the following metathesis reaction, wherein the metathesis reaction time is 4-8 hours:
CaCO produced by metathesis3The slurry is sent into a filter press for filter pressing, and the filter cake is limestone CaCO3The powder material can be recovered and used as raw material for producing cement product, the filtrate is dilute acetic acid liquor, and can be recovered and used as auxiliary material water, and the prepared hydrogen sulfide H can be used2The S gas is used for the absorption reaction,
(4) absorption reaction: in the absorption tank, water is distributed according to 2-4 times of weight of lead oxide PbO to obtain lead oxide liquid, and acetic acid CH is added3COOH (as catalyst in absorption reaction) to regulate and control pH value of liquid in absorption tank to 1-3, and then making hydrogen sulfide H produced in metathesis reaction2S gas is input into an absorption tank to carry out the following absorption reaction, and the absorption reaction time is 4-8 hours:
(5) and (3) filter pressing and cake making: sending the lead sulfide PbS slurry liquid generated by the absorption reaction into a filter press for filter pressing, wherein the filtrate is dilute acetic acid liquid which can be recycled as ingredient water, the filter cake is a lead sulfide PbS cake finished product,
(6) roasting to prepare sulfur: and (2) sending the lead sulfide PbS cake-shaped finished product prepared in the step of filter pressing cake making into a pyrite roasting furnace to roast instead of a pyrite raw material, wherein the roasting reaction formula is as follows:
SO as to prepare sulfur dioxide SO for producing sulfuric acid products2Raw material gas is oxidized to sulfur trioxide SO according to the prior production process for preparing sulfuric acid3And then the qualified sulfuric acid product can be prepared through absorption reaction, and the slag (the main component is PbO) after the sulfur preparation by roasting can be collected and returned to the absorption reaction for recycling.
The production method for preparing sulfuric acid byusing the phosphogypsum waste residue provided by the invention has the main substantive characteristics and remarkable progress that: the method successfully extracts the sulfur ore resource from the phosphogypsum waste residue discharged by phosphate chemical enterprises, can replace pyrite as a raw material for producing sulfuric acid products, recycles the phosphogypsum waste residue, changes waste into valuable to obtain the sulfur ore resource required by preparing sulfuric acid, fundamentally solves the problems of long-term troubles and waste residue pollution restricting the development of phosphorus chemical industry enterprises in China, and has very remarkable environmental protection social benefit and great economic benefit.
Description of the drawings:
the attached figure is a production process flow chart of the invention.
The specific implementation mode is as follows:
the first embodiment is as follows:
the production method for preparing the sulfuric acid by using the phosphogypsum waste residue, which is provided by the invention, is sequentially carried out according to the following steps:
(1) metering and batching: the raw materials for the reaction are as follows by weight:
1 part of phosphogypsum waste residue,
0.25 part of coal, namely,
the weighed raw materials are sent into a crusher to be crushed to prepare a mixed material,
(2) reduction roasting: the prepared mixed material is sent into a converter to carry out reduction roasting reaction, the temperature in the roasting furnace is controlled to be 1000 ℃, the reduction roasting is carried out for 15 minutes under the stirring working condition, and the reduction roasting reaction equation is as follows:
generating calcium sulfide CaS and carbon dioxide flue gas,
(3) double decomposition reaction: feeding calcium sulfide CaS prepared by reduction roasting into a crusher for crushing, feeding water which is 3 times of the weight of the calcium sulfide into a reaction tank, adding acetic acid (serving as a catalyst in a double decomposition reaction) to adjust and control the pH value of liquid in the reaction tank to be 2, and feeding carbon dioxide flue gas generated in the reduction roasting reaction step into the reaction tank for double decomposition reaction for 6 hours as follows:
CaCO produced by metathesis3The slurry is sent into a filter press for filter pressing, and the filter cake is limestone CaCO3The powder material can be recovered and used as raw material for producing cement product, the filtrate is dilute acetic acid solution, can be recovered and used as auxiliary material water,
(4) absorption reaction: adding water in an absorption tank according to the weight of 3 times of that of the lead oxide PbO to prepare lead oxide liquid, and adding acetic acid CH3COOH (as catalyst in absorption reaction) regulation control absorption tankThe pH of the liquid is 2, and the hydrogen sulfide H produced in the double decomposition reaction is2S gas is input into an absorption tank to carry out the following absorption reaction for 6 hours:
so as to prepare the lead sulfide PbS liquid,
(5) and (3) filter pressing and cake making: sending the lead sulfide PbS slurry liquid generated by the absorption reaction into a filter press for filter pressing, wherein the filtrate is dilute acetic acid liquid which can be recycled as ingredient water, the filter cake is a lead sulfide PbS cake finished product,
(6) roasting to prepare sulfur: and (2) sending the lead sulfide PbS cake-shaped finished product prepared in the step of filter pressing cake making into a pyrite roasting furnace to roast instead of a pyrite raw material, wherein the roasting reaction formula is as follows:
SO as to prepare sulfur dioxide SO for producing sulfuric acid products2Raw material gas, then preparing sulfur according to existent methodProduction of acids by oxidation to sulfur trioxide, SO3And then the qualified sulfuric acid product can be prepared through absorption reaction.
Example two:
the method comprises the following steps in sequence:
(1) metering and batching: the raw materials for the reaction are as follows by weight:
1 part of phosphogypsum waste residue,
0.15 part of coal, namely,
the weighed raw materials are sent into a crusher to be crushed to prepare a mixed material,
(2) reduction roasting: the prepared mixed material is sent into a converter to carry out reduction roasting reaction, the temperature in the roasting furnace is controlled to be 800 ℃, the reduction roasting is carried out for 10 minutes under the stirring working condition, and the reduction roasting reaction equation is as follows:
to generate calcium sulfide and carbon dioxide flue gas,
(3) double decomposition reaction: feeding calcium sulfide obtained by reduction roasting into a crusher for crushing, feeding water accounting for 2 times of the weight of the calcium sulfide into a reaction tank, adding acetic acid (serving as a catalyst in double decomposition reaction) to adjust and control the pH value of liquid in the reaction tank to be 1.5, and feeding carbon dioxide CO generated in the reduction roasting reaction2Flue gas is conveyed into the reaction tank to carry out the following metathesis reaction for 5 hours:
CaCO produced by metathesis3The slurry is sent into a filter press for filter pressing, and the filter cake is limestone CaCO3The powder material can be recovered and used as raw material for producing cement product, the filtrate is dilute acetic acid solution, can be recovered and used as auxiliary material water,
(4) absorption reaction: adding water 2 times the weight of lead oxide PbO into an absorption tank to obtain lead oxide liquid, adding acetic acid (as catalyst in absorption reaction) to adjust and control the pH value of the liquid in the absorption tank to 1.5, and adding hydrogen sulfide H generated in double decomposition reaction2S gas is input into an absorption tank to carry out the following absorption reaction for 4 hours:
so as toprepare lead sulfide PbS slurry liquid,
(5) and (3) filter pressing and cake making: sending the lead sulfide PbS slurry liquid generated by the absorption reaction into a filter press for filter pressing, wherein the filtrate is dilute acetic acid liquid which can be recycled as ingredient water, the filter cake is a lead sulfide PbS cake finished product,
(6) roasting to prepare sulfur: and (2) sending the lead sulfide PbS cake-shaped finished product prepared in the step of filter pressing cake making into a pyrite roasting furnace to roast instead of a pyrite raw material, wherein the roasting reaction formula is as follows:
SO as to prepare sulfur dioxide SO for producing sulfuric acid products2Raw material gas, thenThe existing production mode for preparing sulfuric acid is to oxidize SO3And then the qualified sulfuric acid product can be prepared through absorption reaction.
Example three:
the method comprises the following steps in sequence:
(1) metering and batching: the raw materials for the reaction are as follows by weight:
1 part of phosphogypsum waste residue,
0.35 part of coal, namely,
the weighed raw materials are sent into a crusher to be crushed to prepare a mixed material,
(2) reduction roasting: the prepared mixed material is sent into a converter to carry out reduction roasting reaction, the temperature in the roasting furnace is controlled to be 1200 ℃, the reduction roasting reaction is carried out for 20 minutes under the working condition of stirring, and the reduction roasting reaction equation is as follows:
production of calcium sulfide CaS and carbon dioxide CO2The flow rate of the flue gas,
(3) double decomposition reaction: feeding calcium sulfide CaS prepared by reduction roasting into a crusher for crushing, feeding water which is 4 times of the weight of the calcium sulfide into a reaction tank, adding acetic acid (serving as a catalyst in double decomposition reaction) to adjust and control the pH value of liquid in the reaction tank to be 3, and then feeding carbon dioxide CO generated in the reduction roasting reaction2Flue gas is conveyed into the reaction tank to carry out the following metathesis reaction for 8 hours:
CaCO produced by metathesis3The slurry is sent into a filter press for filter pressing, and the filter cake is limestone CaCO3The powder material can be recovered and used as raw material for producing cement product, the filtrate is dilute acetic acid solution, can be recovered and used as auxiliary material water,
(4) absorption reaction: pressing oxygen in the absorption tankAdding water 4 times the weight of the zinc oxide ZnO to prepare zinc oxide slurry, and adding acetic acid CH3Adjusting and controlling the pH value of slurry in the absorption tank to be 3 by COOH (as a catalyst in the absorption reaction), and then adding hydrogen sulfide H generated in the double decomposition reaction2S gas is input into an absorption tank to carry out the following absorption reaction for 8 hours:
to prepare the zinc sulfide ZnS slurry,
(5) and (3) filter pressing and cake making: sending the slurry of zinc sulfide ZnS generated by the absorption reaction into a filter press for filter pressing, wherein the filtrate is dilute acetic acid solution which can be recycled as ingredient water, the filter cake is a finished product of zinc sulfide,
(6) roasting to prepare sulfur: and (2) feeding the zinc sulfide ZnS cake-shaped finished product prepared in the step of filter pressing and cake making into a pyrite roasting furnace to roast instead of the pyrite raw material, wherein the roasting reaction formula is as follows:
SO as to prepare sulfur dioxide SO for producing sulfuric acid products2The raw material gas is oxidized to sulfur trioxide SO according to the existing production mode for preparing sulfuric acid3And then the qualified sulfuric acid product can be prepared through absorption reaction.
Claims (2)
1. A production method for preparing sulfuric acid by using phosphogypsum waste residues is characterized by sequentially comprising the following steps:
(1) metering and batching: the raw materials for the reaction are as follows by weight:
1 part of phosphogypsum waste residue,
0.15-0.35 portion of coal,
weighing raw materials in a certain amount, feeding into a pulverizer to pulverize to obtain a mixed material,
(2) reduction roasting: the mixed material is sent into a roasting furnace to be roasted for 10-20 minutes at 800-1200 ℃ to obtain calcium sulfide,
(3) double decomposition reaction: delivering the calcium sulfide obtained by reduction roasting into a crusher for crushing, delivering the calcium sulfide into a reaction tank by water distribution of 2-4 times of the weight of the calcium sulfide, adding acetic acid to adjust the pH value to 1-3, delivering carbon dioxide flue gas for double decomposition reaction for 4-8 hours to obtain hydrogen sulfide,
(4) absorption reaction: preparing liquid by water in the absorption tank in a weight 2-4 times of that of the lead oxide, adding acetic acid to regulate the pH value to 1-3, inputting the hydrogen sulfide gas prepared in the double decomposition reaction into the absorption tank for absorption reaction for 4-8 hours to prepare lead sulfide liquid,
(5) and (3) filter pressing and cake making: sending the lead sulfide liquid generated by the absorption reaction into a filter press for filter pressing to obtain a lead sulfide finished product,
(6) roasting to prepare sulfur: and (3) feeding the finished lead sulfide product prepared in the step of pressing and filtering to prepare a cake into a roasting furnace for roasting to prepare a sulfur dioxide feed gas, oxidizing the sulfur dioxide feed gas to sulfur trioxide, and performing absorption reaction to prepare a qualified sulfuric acid product.
2. The production method for preparing sulfuric acid by using phosphogypsum waste residues as claimed in claim 1, which is characterized in that: zinc oxide is used in place of lead oxide in the absorption reaction step.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100460317C (en) * | 2007-01-17 | 2009-02-11 | 贵州大学 | New method for producing calcium sulfide by using phosphogypsum |
| CN101885600A (en) * | 2010-07-21 | 2010-11-17 | 中南大学 | Heavy metal waste slag treatment method and sulfur building material prepared thereby |
| CN101891160A (en) * | 2010-06-21 | 2010-11-24 | 尹小林 | Method for directly preparing sulfur trioxide and sulfuric acid from plaster |
| CN101693641B (en) * | 2009-10-22 | 2010-12-22 | 南京信息工程大学 | Compound bio-fertilizer containing ardealite and application thereof |
| CN103408052A (en) * | 2013-07-25 | 2013-11-27 | 昆明理工大学 | Decomposition method of ardealite |
| CN104831076A (en) * | 2015-06-04 | 2015-08-12 | 山东恒邦冶炼股份有限公司 | Resource recycling process of solid waste calcium sulfate |
| CN105905872A (en) * | 2016-05-30 | 2016-08-31 | 禄丰天宝磷化工有限公司 | Method for producing sulfuric acid and quick lime by utilizing phosphogypsum |
| CN111020175A (en) * | 2019-11-18 | 2020-04-17 | 中南大学 | Method for comprehensively recycling zinc-rich gypsum slag resources |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US4503018A (en) * | 1983-02-14 | 1985-03-05 | Davy Mckee Corporation | Desulfurization of phosphogypsum |
| US5066474A (en) * | 1988-05-10 | 1991-11-19 | Science Ventures, Inc. | Method for sulfur dioxide production from calcium sulfate by entrained high-temperature slagging reduction |
| CN1052965C (en) * | 1996-04-05 | 2000-05-31 | 南京化工大学 | Technology for production of cement and sulfuric acid by phosphor gypsum |
| CN1141168C (en) * | 1998-04-01 | 2004-03-10 | 富兰克林·S·查默斯 | Method of processing sulfur-containing materials derived from flue gas desulfurization or other sources |
| CN1203833A (en) * | 1998-05-06 | 1999-01-06 | 中国科学院生态环境研究中心 | Method for reduction of desulfurized waste residue, phosphogypsum or natural gypsum |
| CN1227824A (en) * | 1998-11-27 | 1999-09-08 | 遵化市化肥厂 | Improved method for producing sulfuric acid and jointly producing cement |
| CN1194898C (en) * | 2001-10-15 | 2005-03-30 | 广西大学 | Process for preparing both barium sulfate and calcium chloride from waste ardealite dregs |
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2005
- 2005-11-18 CN CNB200510022084XA patent/CN100360397C/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100460317C (en) * | 2007-01-17 | 2009-02-11 | 贵州大学 | New method for producing calcium sulfide by using phosphogypsum |
| CN101693641B (en) * | 2009-10-22 | 2010-12-22 | 南京信息工程大学 | Compound bio-fertilizer containing ardealite and application thereof |
| CN101891160A (en) * | 2010-06-21 | 2010-11-24 | 尹小林 | Method for directly preparing sulfur trioxide and sulfuric acid from plaster |
| CN101891160B (en) * | 2010-06-21 | 2011-10-26 | 尹小林 | Method for directly preparing sulfur trioxide and sulfuric acid from plaster |
| CN101885600A (en) * | 2010-07-21 | 2010-11-17 | 中南大学 | Heavy metal waste slag treatment method and sulfur building material prepared thereby |
| CN101885600B (en) * | 2010-07-21 | 2012-07-25 | 中南大学 | Heavy metal waste slag treatment method and sulfur building material prepared thereby |
| CN103408052A (en) * | 2013-07-25 | 2013-11-27 | 昆明理工大学 | Decomposition method of ardealite |
| CN103408052B (en) * | 2013-07-25 | 2016-01-13 | 昆明理工大学 | A kind of decomposition method of phosphogypsum |
| CN104831076A (en) * | 2015-06-04 | 2015-08-12 | 山东恒邦冶炼股份有限公司 | Resource recycling process of solid waste calcium sulfate |
| CN105905872A (en) * | 2016-05-30 | 2016-08-31 | 禄丰天宝磷化工有限公司 | Method for producing sulfuric acid and quick lime by utilizing phosphogypsum |
| CN111020175A (en) * | 2019-11-18 | 2020-04-17 | 中南大学 | Method for comprehensively recycling zinc-rich gypsum slag resources |
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