CN102275992A - Two-stage roasting method for chromite - Google Patents
Two-stage roasting method for chromite Download PDFInfo
- Publication number
- CN102275992A CN102275992A CN2011101445691A CN201110144569A CN102275992A CN 102275992 A CN102275992 A CN 102275992A CN 2011101445691 A CN2011101445691 A CN 2011101445691A CN 201110144569 A CN201110144569 A CN 201110144569A CN 102275992 A CN102275992 A CN 102275992A
- Authority
- CN
- China
- Prior art keywords
- chromite
- roasting
- kiln
- slag
- leaching
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Processing Of Solid Wastes (AREA)
Abstract
The invention discloses a two-stage roasting method for chromite and particularly relates to a non-calcium two-stage roasting method for chromite. The method comprises the following steps: mixing chromite, sorted return slag and sodium carbonate, transferring into a first kiln, heating the mixture in the first kiln under the condition that oxygen is excluded, transferring the product into a second kiln, ventilating before heating, leaching and washing the obtained solid clinker, returning the sorted chromium slag to the mixing stage, and detoxifying the tailing for comprehensive utilization. Compared with the prior art, the chromite oxidation ratio of the method is high, the reaction rate is higher, and the leaching rate is high; and the utilization of the return slag can save the cost and reduce pollutions. Thus, in the non-calcium roasting field of chromium salt, the method has popularization and application values for environmental protection and enterprise benefit gaining.
Description
Technical field
The present invention relates to a kind of calcium-free roasting technology of chromite, particularly a kind of no calcium two-section roasting of chromite.
Background technology
At present, chromite oxidizing roasting method almost is the unique method of chromium salt production, wherein be divided into calcium roasting method and calcium-free roasting method are arranged, its something in common is it all is that chromite and soda ash are carried out roasting under the high temperature oxidation condition, makes the chromium in the ore be converted into water miscible Sodium chromate through subsequent disposal such as leaching acquisition chromic salts product.Calcium-free roasting method uses return slag to replace the calcic filler, chromium slag quantity discharged reduces greatly and does not contain high malicious yellow ultramarine, become the main stream approach of chromium salt production, documents 200710017747.8 discloses a kind of method of being produced Sodium chromate by chromite through calcium-free roasting, with chromite, yellow soda ash and return slag mix, in rotary kiln, carry out oxidizing roasting, this method is directly carried out oxidizing roasting with mixture, picotite and soda ash and oxygen direct reaction are produced Sodium chromate, because picotite is difficult for reaction, cause entire reaction speed to be carried out slowly, so it is not high that chromite fails fully to react leaching rate, there is imagination to improve reaction efficiency in the external relevant document, but fails to realize owing to lacking concrete working method by the two-stage roasting of chromite.
Summary of the invention
At above-mentioned the deficiencies in the prior art part, the invention provides a kind of chromite two-section roasting that can accelerate chromite roasting speed of response.
To achieve these goals, the technical solution used in the present invention is:
A. batch mixing: return slag and soda ash precentagewise X:Y:Z that chromite, sorting are obtained mix, and uniformity coefficient reaches 90～110%, and wherein X is 100, and Y is 70～90, and Z is 140～300;
B. anaerobic roasting: the batch mixing that obtains in the steps A is heated at the first kiln secluding air, and calcining temperature is 500 ℃, calcines 1 hour;
C. aerobic roasting: will send into second kiln through the batch mixing of heating among the step B, bubbling air carries out roasting, 1150 ℃ of high temperature zone temperatures, and 500 ℃ of kiln end temperatures were calcined 2～3 hours;
D. leaching: the solid grog that obtains among the step C is cooled off the back to 200 ℃～300 ℃, send into subsequent processing leaching washing;
E. the processing of chromium slag: residue chromium slag returns calcining process among the step D after sorting, tailings detoxifcation back comprehensive utilization.
The technical program adopts two-stage method has been adopted in the roasting of batch mixing, in first kiln batch mixing secluding air is heated, and picotite is heated to 500 ℃ at oxygen free condition, and the picotite lattice is distorted, and potential energy raises, and is easy to reaction, the main and Cr of soda ash
2O
3, Al
2O
3And Fe
2O
3Reaction obtains NaFeO
2, NaAlO
2And NaCrO
2, batch mixing continues to enter second kiln, bubbling air, NaCrO
2Gas and oxygen reaction obtain Sodium chromate, NaAlO
2And NaCrO
2Play the alkalescence effect, adopt such method, fully oxidation of picotite, reaction generates more chromic salts, helps improving leaching rate.
As preferably, in the steps A chromite levigate to 200 orders by more than 70%, the finished product additive is levigate to 150 orders by 90%, return slag is levigate to 200 orders by more than 70%; Reduce the grain graininess of each raw material like this, each raw material contact surface is increased, improved speed of response.
As preferably, the stack gas that produces among steps A and the step B is disposed in the air through settling pocket, waste heat boiler and electrostatic precipitator; Waste gas is handled, and the toxic gas that produces in preventing to burn directly is disposed to air and pollutes, and the powder that fly-ash separator is collected can recycle once more, and the steam of used heat pot can be sent into steam-pipe utilization.
Compared with prior art; this beneficial effect of the invention: the present invention adopts the two-stage method roasting chromite to produce Sodium chromate; chromite oxidation ratio height; speed of response is faster; the leaching rate height; and the utilization of return slag has been saved cost and has been reduced pollution, therefore in the chromium salt calcium-free roasting field, all has application value from environment protection, still on the performance of enterprises.
Embodiment
The present invention is described in further detail below in conjunction with specific embodiment.
Embodiment 1: the invention discloses a kind of chromite two-section roasting, its step is as follows:
One, the mixing of raw material: chromite drying, abrasive dust to 200 order are by more than 70%, return slag drying after the sorting, abrasive dust to 200 order are by more than 70%, with per-cent is 100:70: 140 chromite, return slag and soda ash are sent into biaxial rneader and are mixed, and the compound uniformity coefficient reaches 90% after worm conveyor, lift are delivered to blending bun.
Two, roasting: be divided into aerobic stage and anaerobic stage, batch mixing passes through aerobic stage and anaerobic stage successively;
The main reaction that chromite and soda ash and oxygen take place in the roasting is:
Cr
2O
3?+?2Na
2CO
3?+?1.5O
2＝2Na
2CrO
4?+2?CO
2?+?Q ①
1, the anaerobic stage: weighing belt is sent the batch mixing spiral into first kiln, and the mixture of chromite and soda ash was calcined 1 hour under the condition of starvation, 500 ℃ of kiln temperatures, and when picotite is heated to 500 ℃, Fe
2+At first be oxidized to Fe
3+Thereby, the spinel lattice is distorted, potential energy raises, and is easy to reaction.
Soda ash is same R earlier
2O
3Reaction generates NaRO
3, i.e. chromous acid sodium (NaCrO
2), sodium aluminate (NaAlO
2) and sodium ferrite (NaFeO
2), described reaction formula is:
Cr
2O
3+Na
2CO
3＝2NaCrO
2?+?CO
2 ②
Al
2O
3?+?Na
2CO
3＝2NaAlO
2?+?CO
2 ③
Fe
2O
3 +?Na
2CO
3＝2NaFeO
2?+?CO
2 ④
2, the aerobic stage: the batch mixing that comes out from the anaerobic stage enters second kiln, the bubbling air roasting, and high temperature zone temperature is 1150 ℃ in the kiln, and 500 ℃ of kiln end temperatures were calcined 3 hours; In high-temperature oxidation environment, chromous acid sodium (NaCrO
2) continue reaction generation Na with oxygen and soda ash immediately
2CrO
4Sodium aluminate (NaAlO
2) and sodium ferrite (NaFeO
2) also play the alkalescence effect, make NaCrO
2Be oxidized to Na
2CrO
4
2NaCrO
2 +?Na
2CO
3?+?1.5O
2＝2Na
2CrO
4?+?CO
2?+?Q ⑤
2NaCrO
2 +?2NaAlO
2?+?1.5O
2＝2Na
2CrO
4+?Al
2O
3?+?Q ⑥
2NaCrO
2 +?NaFeO
2?+?1.5O
2＝2Na
2CrO
4+?Fe
2O
3+?Q ⑦
Wherein, the side reaction that takes place in the roasting is: Na
2CO
3Remove with chromite take place 3., 4., 1. reaction generates NaRO
2And Na
2CrO
4Outward, also with impurity SiO in the ore deposit
2, V
2O
5Reaction generates the lower product (Na of molten point
2SiO
3, NaVO
3); N
2SiO
3And NaAlO
2Not only can provide sodium ion, make that 6. trivalent chromium takes place, reaction 9. changes Sodium chromate into, and both also generate aluminum magnesium silicate sodium (Na with magnesium oxide generation complex reaction
4MgAl
2Si
3O
12).
Si＋Na
2CO
3＝Na?
2?SiO
3＋CO
2 ⑧
V
2O
5＋Na
2CO
3?＝2NaVO
3＋CO
2 ⑨
Na
2SiO
3?＋2NaCrO
2＋1.5O
2＝2?Na
2CrO
4＋SiO
2 ⑩
Na
2SiO
3?＋2NaAlO
2＋MgO＋2SiO
2＝Na?
4MgAl
2Si
3O
The Na that 8., 9. formula generates
2SiO
3And NaAlO
2Make grog contain water-soluble silicon, aluminium, and its back-pushed-type
Further reaction is transformed into Sodium chromate and generates water-fast aluminum magnesium silicate sodium, then can reduce water-soluble silicon, aluminium.
The stack gas that roasting produces after settling pocket, waste heat boiler and electrostatic precipitator gas through smoke stack emission to atmosphere, the powder that dedusting is got off in the fly-ash separator submits to kiln ash storehouse through the spiral bucket, and in the process of batching, use, the steam that waste heat boiler produces is delivered to steam pipe system, uses for full factory.
Three, leaching and washing
Batch mixing is through becoming the solid grog that contains Sodium chromate after the roasting, and the solid grog is cooled to 200 ℃ through cooler, enters the leaching car and leaches and wash.
Four, the processing of chromium slag
Part chromium slag is used for roasting after super-dry, part chromium slag is through rod milling, wet concentration, and thick slag is used for calcining process through band filter, dry back as return slag;
Thin slag fully utilizes after the detoxifcation through behind the box filter, for example: ironmaking, production cement, brickmaking and glass colorant etc.
The above only is the detailed description of preferred embodiment of the present invention, is not to be used for limiting the present invention, and the embodiment of all similar variations of doing according to creation spirit of the present invention all should be contained among the present invention.
Claims (3)
1.. the chromite two-section roasting is characterized in that it may further comprise the steps:
A. batch mixing: return slag and soda ash precentagewise X:Y:Z that chromite, sorting are obtained mix, and uniformity coefficient reaches 90～110%, and wherein X is 100, and Y is 70～90, and Z is 140～300;
B. anaerobic roasting: the batch mixing that obtains in the steps A is heated at the first kiln secluding air, and calcining temperature is 500 ℃, calcines 1 hour;
C. aerobic roasting: will send into second kiln through the batch mixing of heating among the step B, bubbling air carries out roasting, 1150 ℃ of high temperature zone temperatures, and 500 ℃ of kiln end temperatures were calcined 2～3 hours;
D. leaching: the solid grog that obtains among the step C is cooled off the back to 200 ℃～300 ℃, send into subsequent processing leaching washing;
E. the processing of chromium slag: residue chromium slag returns calcining process among the step D after sorting, tailings detoxifcation back comprehensive utilization.
2. chromite two-section roasting according to claim 1 is characterized in that: in the described steps A chromite levigate to 200 orders by more than 70%, return slag is levigate to 200 orders by more than 70%.
3. chromite two-section roasting according to claim 1 is characterized in that: the stack gas that produces among described steps A and the step B is disposed in the air through settling pocket, waste heat boiler and electrostatic precipitator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110144569 CN102275992B (en) | 2011-05-31 | 2011-05-31 | Two-stage roasting method for chromite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110144569 CN102275992B (en) | 2011-05-31 | 2011-05-31 | Two-stage roasting method for chromite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102275992A true CN102275992A (en) | 2011-12-14 |
| CN102275992B CN102275992B (en) | 2013-06-26 |
Family
ID=45101795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110144569 Active CN102275992B (en) | 2011-05-31 | 2011-05-31 | Two-stage roasting method for chromite |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102275992B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102627329A (en) * | 2012-04-27 | 2012-08-08 | 甘肃锦世化工有限责任公司 | Method for improving chromium conversion rate of chromium salt rotary kiln by using calcium-free fillers |
| CN104098139A (en) * | 2014-06-27 | 2014-10-15 | 四川省银河化学股份有限公司 | Method for preparing sodium chromate by adopting sulfate byproduct iron cake as calcium-free roasting filler |
| CN108358246A (en) * | 2018-01-09 | 2018-08-03 | 中南大学 | A kind of preparation method and application of chromium sodium ferrite material |
| CN110093496A (en) * | 2019-05-10 | 2019-08-06 | 四川久远环境技术有限公司 | A kind of ferrochrome dust resourcesization containing chromium powder utilize method |
| CN112661186A (en) * | 2020-12-25 | 2021-04-16 | 四川省绵阳市华意达化工有限公司 | Method for bottom blowing oxygen-enriched low-alkali roasting of chromite |
| CN114105199A (en) * | 2021-11-24 | 2022-03-01 | 四川省绵阳市华意达化工有限公司 | Roasting method for improving chromium and aluminum conversion rate of chromite |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4244925A (en) * | 1979-07-20 | 1981-01-13 | Allied Chemical Corporation | Method for production of alkali metal chromates from chrome ores |
| CN101045559A (en) * | 2007-04-19 | 2007-10-03 | 甘肃锦世化工有限责任公司 | Method for producing sodium chromate non-calcium calcined by ferrochrome mine |
| CN101717119A (en) * | 2009-11-23 | 2010-06-02 | 新疆沈宏集团股份有限公司 | Method for producing sodium chromate by roasting chromium ore and small amount of soda |
-
2011
- 2011-05-31 CN CN 201110144569 patent/CN102275992B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4244925A (en) * | 1979-07-20 | 1981-01-13 | Allied Chemical Corporation | Method for production of alkali metal chromates from chrome ores |
| CN101045559A (en) * | 2007-04-19 | 2007-10-03 | 甘肃锦世化工有限责任公司 | Method for producing sodium chromate non-calcium calcined by ferrochrome mine |
| CN101717119A (en) * | 2009-11-23 | 2010-06-02 | 新疆沈宏集团股份有限公司 | Method for producing sodium chromate by roasting chromium ore and small amount of soda |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102627329A (en) * | 2012-04-27 | 2012-08-08 | 甘肃锦世化工有限责任公司 | Method for improving chromium conversion rate of chromium salt rotary kiln by using calcium-free fillers |
| CN104098139A (en) * | 2014-06-27 | 2014-10-15 | 四川省银河化学股份有限公司 | Method for preparing sodium chromate by adopting sulfate byproduct iron cake as calcium-free roasting filler |
| CN104098139B (en) * | 2014-06-27 | 2016-03-02 | 四川省银河化学股份有限公司 | A kind of sulfuric acid by-product scum does the method that Sodium chromate prepared by calcium-free roasting stopping composition |
| CN108358246A (en) * | 2018-01-09 | 2018-08-03 | 中南大学 | A kind of preparation method and application of chromium sodium ferrite material |
| CN108358246B (en) * | 2018-01-09 | 2019-12-10 | 中南大学 | Preparation method and application of sodium ferrochrome material |
| CN110093496A (en) * | 2019-05-10 | 2019-08-06 | 四川久远环境技术有限公司 | A kind of ferrochrome dust resourcesization containing chromium powder utilize method |
| CN112661186A (en) * | 2020-12-25 | 2021-04-16 | 四川省绵阳市华意达化工有限公司 | Method for bottom blowing oxygen-enriched low-alkali roasting of chromite |
| CN114105199A (en) * | 2021-11-24 | 2022-03-01 | 四川省绵阳市华意达化工有限公司 | Roasting method for improving chromium and aluminum conversion rate of chromite |
| CN114105199B (en) * | 2021-11-24 | 2024-01-02 | 四川省绵阳市华意达化工有限公司 | Roasting method for improving chromium and aluminum conversion rate of chromite |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102275992B (en) | 2013-06-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103771734B (en) | A kind of mass-producing calcination processing utilizes the method for electrolytic manganese residues | |
| CN102275992B (en) | Two-stage roasting method for chromite | |
| CN104478255B (en) | A kind of magnesium oxysulfide concrete containing magnesia FGD waste liquid and preparation method thereof | |
| CN101003422B (en) | New method for producing sulfuric acid and cement by using phosphogypsum | |
| CN102502524B (en) | Method for producing sulfur dioxide from calcium sulfate and sulfur | |
| CN101041449A (en) | Method for extracting aluminium oxide from coal ash and producing cement by using waste slag | |
| CN112661424B (en) | Environment-friendly cement and preparation method thereof | |
| CN102173619B (en) | High-volume fly ash cement production technique and pulverizing technique | |
| CN108178536B (en) | Method for preparing low-clinker cement by calcining coal gasification slag step by step | |
| CN105712642A (en) | Efficient expansion clinker for cement concrete, preparation method of efficient expansion clinker and application of efficient expansion clinker | |
| CN111517679A (en) | Multi-solid waste early strength cement and preparation method thereof | |
| CN105110666B (en) | The method that the discarded object produced using calcium carbide prepares clinker | |
| CN104003633B (en) | Preparation method of silicate clinker and cement and rotary kiln for preparing silicate clinker | |
| CN111233353A (en) | Method for producing general cement clinker by using iron oxide slag to partially replace iron correction raw material | |
| CN101003365A (en) | New method for producing calcium sulfide by using phosphogypsum | |
| CN105152141B (en) | A kind of gypsum relieving haperacidity thermal technology and device | |
| CN102320761B (en) | Method for preparing cement active mixed material and concrete active admixture | |
| CN113526882B (en) | Portland cement clinker and preparation method thereof | |
| CN102234171A (en) | Process for recycling alkali and synchronously producing cement by roasting red mud | |
| CN105621909A (en) | Compound doped cement with modified desulfurization ash and rice hull ash | |
| CN104961473A (en) | Method for producing export magnesium-rich olivine sand with MgO content less than 70% | |
| CN116178033B (en) | Method for preparing refractory brick by using aluminum ash and product thereof | |
| CN101239706B (en) | Method for producing calcium sulfide from calcium sulfate | |
| CN107304126A (en) | A kind of slag haydite | |
| CN214747299U (en) | Device for producing mineral admixture by using coal gangue |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |