CN102417312A - Resource utilization method for chrome-containing aluminum sludge - Google Patents

Abstract

The invention discloses a resource utilization method for chrome-containing aluminum sludge. The method comprises the following steps: 1) roasting the aluminum sludge at high temperature to realize matter sizing; 2) washing and recycling hexavalent chromium (sodium chromate) and sodium sulfate; 3) soaking in a ferrite solution, thereby thoroughly detoxifying the hexavalent chromium Cr6+; and 4) mixing the hexavalent chromium, limestone and gypsum to prepare a special cement of sulphate aluminum or aluminates. According to the method disclosed by the invention, the chrome-containing aluminum sludge is thoroughly detoxified, all components of the chrome-containing aluminum sludge are utilized as the resources, the clean and harmless as well as recycling zero-release utilization of the chrome-containing aluminum sludge is realized, the pollution level of the chromium salt industry is efficiently relieved, the level of clean production of the chromium salt is boosted and the popularizing demonstrative property is excellent.

Description

The resource utilization method of aluminium chromium dosed slag

Technical field

Patent of the present invention belongs to environmental protection, building materials field, the method for particularly a kind of recycling aluminium chromium dosed slag system sulplo-aluminate or aluminate special cement.

Background technology

In the chromium salt production roasting process, carry out soda ash and chromite and generate Sodium chromate-51Cr (Na ₂CrO ₄) generate sodium aluminate (Na with oxidation of impurities reactive aluminum in soda ash and the chromite main reaction time ₂AlO ₂) side reaction.Through the leaching operation, Sodium chromate-51Cr, sodium aluminate and unreacted soda ash enter in the solution, and when filtering, because the control fault of technology and penetrating of filter cloth make bits also get into solution on a small quantity.For guaranteeing from the higher chromic salts basic product sodium dichromate 99 (Na of Sodium chromate-51Cr acidifying production purity ₂Cr ₂O ₇), the aluminium scavenging process that must neutralize, these process concrete operations are: in solution, add the sodium pyrosulfate waste liquid that produces in sulfuric acid or the chromic acid production of chromic salts enterprise, PH was near 7 o'clock in adjustment, and sodium aluminate just progressively changes white lake Al (OH) in the solution ₃Deposition is filtered with filter again, and the chromium slag of bringing in the solution and the white lake of generation are filtered simultaneously.And, be stained with sexavalence chromic salts Sodium chromate-51Cr (Na because white lake has very strong colloidal property ₂CrO ₄), being not easy to be cleaned, this slag is called as " aluminium chromium dosed slag (mud) " in the chromic salts industry

Because different manufacturers baking operation level difference, aluminium chromium dosed quantity of slag difference is bigger.The mobility scale of the aluminium quantity of slag is 20～200kg (wet basis)/t product.The staple white lake Al (OH) of aluminium chromium dosed slag ₃(with Al ₂O ₃Meter) 30%～45%, contain sexavalence chromic salts Sodium chromate-51Cr Na ₂CrO ₄(with Cr ⁶⁺Meter) 0.5%～1.2%.Impurity Cr ₂O ₃0.8%～1.2%, sodium sulfate Na ₂SO ₄2%～3.5%, Fe ₂O ₃1%～3.5%, SiO ₂0.5%～2%, free-water adds up to 45%～55% in crystal water in the white lake and the slag.Below all refer to the mass percent of each composition in the aluminium body refuse.

At present this aluminium chromium dosed body refuse utilize mode many, have following several kinds after the contrast substantially:

1, aluminium chromium dosed slag high temperature cures the recovery sexavalent chrome, and this method mainly dries by the fire free-water and the partial crystallization water in the aluminium slag, makes to be difficult to filtering colloidal hydroxide aluminium Al (OH) ₃Progressively lose near water and change the thick aluminum oxide of crystal into, adopt again and soak flush away sexavalence chromic salts, reach and reclaim chromic purpose.The chromium slag that produces in aluminium slag after treatment and the chromium salt production mixes, and unifies detoxifcation again and handles airtight the storing up in special-purpose slag field.This method is that the aluminium chromium dosed slag that present China chromium salt production producer adopts is handled main way.

This method shortcoming is: stoving temperature is at 300 ℃～700 ℃, and occupied ground is big, and environment is poor, and curing flue dust has secondary pollution.Most critical be only to have reclaimed maximum 98% sexavalence chromic salts, other compositions are closed to abandon to be stored up, though environment is not caused the solvable hexavalent chromium polluted of persistence, does not fundamentally effectively utilize its resource, has caused waste.

2, the phosphoric acid chemical method reclaims the sexavalence chromic salts

In aluminium mud, add phosphoric acid, make colloidal white lake Al (OH) ₃Be transformed into phosphagel phosphaljel AlPO ₄Crystal improves the strainability of aluminium mud, so that reclaim Sodium chromate-51Cr.

This method shortcoming is: though secondary dust and the occupied ground of having avoided baking process(of sulfonation) to produce are big; Cause the problem of environment difference; But not only exist introducing high value phosphoric acid to handle, increase the disadvantage of processing cost, and the waste residue after handling equally also can not get abundant recycling.Economic worth is lower in practice.

3, aluminium chromium dosed slag system chromium aluminium tanning agent

Sulfuric acid acidation use in aluminium chromium dosed slag dissolving back, and making the Sodium chromate-51Cr acidifying in the aluminium slag is sodium dichromate 99, and adopting sucrose again is trivalent chromium with hexavalent chrome reduction, adjusts basicity with soda ash again, produces basic chromium sulfate aluminium, through super-dry and obtain the chromium aluminum tanning agent, is used for leather and ferments.

The shortcoming of this method is: the iron level in the finished product requires lower, and less than 0.1%, the iron level in the corresponding requirements raw material is also low so.Directly with aluminium chromium dosed slag system chromium aluminum tanning agent, its quality is difficult to up to standard, produces in the chromium aluminum tanning agent technology and only can add on a small quantity.Its utilization is limited, and the chromium aluminum tanning agent utilize limitation bigger, also can't substitute the basic chromium sulfate tanning agent at present, can't form large-scale industrial production, this technology is few in the producer that the chromic salts industry adopts.

4, the application of aluminium chromium dosed slag in cement

After Jinanyuxing Chemical General Factory has also been carried out aluminium slag and the mixing of chromium slag; In cement slurry, add the experimental study of producing ordinary Portland cement; And having obtained success, the add-on maximum of aluminium chromium dosed slag in raw material can account for 0.8% of raw material total mass, solubility sexavalent chrome Cr in the cement clinker ⁶⁺Account for 0.15% of grog total mass.

The main drawback of this aspect: the adapted amount in raw material is very low, in theory with experiment in feasible, but receive the influence of industriallization batch mixing uniformity coefficient, so few incorporation is unfavorable for production control, so quality can be very unstable.Moreover, there is 0.15% solubility sexavalent chrome in the cement clinker, using is that certain harm is arranged under construction.

To sum up state, the aluminium chromium dosed body refuse of chromium salt production generation at present is along with technological development constantly and research; Progressively carried out certain improvement; Avoided unrest row in the past to leave about contaminate environment, but, caused this bauxite resource that just lacks of China to be wasted not fully by recycling.And China is used for military salvaging; Highway pavement is promptly repaired; The fast hard fast strong type special cement of various emergency occasions such as tunnel, underground contruction, pond, boats and ships leak stopping yields poorly; Developed country has property special cement production capacity and accounted for 7%～9% of whole cement production capacities, and China's present situation is a less than 2%～3%, and is quite backward.The present invention is intended to study the method for a kind of recycling aluminium chromium dosed slag system sulplo-aluminate or aluminate special cement; This method organically combines the production of detoxifcation of aluminium chromium dosed slag and special cement, can realize that the aluminium chromium dosed slag cleans, innoxious, recycling and zero discharge utilization.Can alleviate the pollution level of chromic salts industry effectively, promote the chromic salts industry to clean production level, have economic implications and social benefit very doughtily, also can fill up the uneven in development contradiction of China's special cement.

Summary of the invention

For recycling aluminium chromium dosed slag system sulplo-aluminate or aluminate special cement; And the aluminium chromium dosed slag that makes the neutralization of calcium-free roasting novel process production sodium dichromate 99 go the aluminium process to produce has obtained whole comprehensive utilizations; Realized zero release, the present invention adopts following technical scheme:

Aluminium chromium dosed slag in the chromium salt production separates the salt and the sexavalent chrome of solubility through high-temperature roasting, washing, soaks detoxifcation with the ferrous salt wet method, remakes to be main material production sulplo-aluminate or aluminate special cement.

The first step: aluminium chromium dosed slag high-temperature roasting material typing makes it be converted into the stable loose shape oxidation state material of dry-matter that is:

The aluminium chromium dosed body refuse adopts roasting apparatuss such as reverberatory furnace, rotary kiln, shuttle kiln, pushed bat kiln, and adopting coal dust or lump coal is thermal source, also can utilize industrial exhaust heat.Roasting 1h～3h under 900 ℃～1050 ℃ high temperature.Reactions such as water evaporates, crystalline transformation take place when roasting, as:

H ₂O (liquid) → H ₂O ↑ (100 ℃)

Na ₂CrO ₄·4H ₂O→Na ₂CrO ₄+4H ₂O(68℃)

Al ₂(OH) ₃→AlOOH(200～250℃)→γ-Al ₂O ₃(400～500℃)

Dry material is loose and porous structure, Cr ₂O ₃, SiO ₂, Fe ₂O ₃All be dispersed in γ-Al etc. the oxidation state material ₂O ₃In the material.

Second step: washing and recycling soluble salt

The first step is handled the dry material that obtains be loose many hollow structures, interior contains sodium sulfate Na ₂SO ₄, Sodium chromate-51Cr Na ₂CrO ₄Enrichment, and soluble in water, directly just can remove with 60 ℃～80 ℃ soaking and washing, wash water gets into the chromium salt production system and utilizes, and just can all reclaim Na ₂SO ₄, Na ₂CrO ₄Na ₂SO ₄In chromium salt production, remove the nitre operation and just can separate, be used further to produce the Sodium Sulphide product after the separation.Na ₂CrO ₄Be to produce major product, directly recycle.The quality percentage composition that its water-soluble salt is detected in aluminium chromium dosed slag oven dry back, washing back is no more than 0.5%, can guarantee the normal use of subsequent handling.

The 3rd step: thorough wet method detoxifcation sexavalent chrome Cr ⁶⁺

Aluminium chromium dosed body refuse after the processing of second step is immersed in saturated ferrous sulfate FeSO ₄.7H ₂In the O solution, not by the sexavalent chrome Cr that cleans ⁶⁺By ferrous sulfate FeSO ₄In ferrous radical ion Fe ²⁺Reduction is converted into trivalent chromium Cr ³⁺, along with the increase of concentration progressively is oxidized to chromium sesquioxide Cr ₂O ₃In the deposition, filter in the entering aluminium chromium dosed slag.

Cr ⁶⁺Detoxifcation main chemical reactions formula:

2Na ₂CrO ₄+6FeSO ₄+8H ₄SO ₄＝Cr ₂(SO ₂) ₃+3Fe ₂(SO ₂) ₃+2Na ₂SO ₄+8H ₂O

Cr ₂(S?O ₄) ₃+6OH ^-＝Cr ₂O ₃+3SO ₄ ^2-

Take out a little solution, drop on the whiteware plate, on solution, drip sulfuric acid and phenylbenzene diamino indicator, solution is purple not, is regarded as in the solution non-hexavalent chromium.This method is that colourimetry detects chromic method.

The 4th step: system sulplo-aluminate or aluminate special cement

Staple ω (the Al of aluminium body refuse ₂O ₃)＞75%, ω (SiO ₂)＞2%, ω (Fe ₂O ₃)＞4%, ω (Cr ₂O ₃)＞2.5% can be produced with gypsum, raw meal prepared from lime and to make fast strong fast gravity die sulplo-aluminate or aluminate special cement.

Wingdale basal component requires: ω (CaO)＞52%, ω (MgO)＜1.5%;

Dihydrate gypsum basal component requires: ω (SO ₃)＞38%, ω (MgO)＜3%.

The sulfoaluminate clinker mineral that patent of the present invention is produced are with anhydrous calcium sulphoaluminate 3 (CaO.Al ₂O ₃) .CaSO (is abbreviated as C ₄A ₃S) and Dicalcium Phosphate (Feed Grade) β-C ₂S is main, also has a spot of CaSO ₄, chromite (CrF) equates.The chemical constitution of grog is roughly CaO 40%～44%, Al ₂O ₃18%～22%, SiO ₂8%～12%, Fe ₂O ₃6%～10%, SO ₃12%～16%,, Cr ₂O ₃0.3%～0.6%, its corresponding mineral composition generally is C ₄A ₃S 36%～44%, β-C ₂S 23%～34%, C ₂F10%～27%, CaSO ₄4%～17%.Because essential mineral is C ₄A ₃S-β-C ₂So S is usually with C ₄A ₃S-β-C ₂The S type is represented quick hardening sulphoaluminate cement.Produce C ₄A ₃S-β-C ₂During S type cement clinker, two rate values of major control, i.e. basicity factor (Cm) and aluminium-sulfur ratio (Ps), its calculation formula is following:

Basicity factor $\mathrm{Cm}=\frac{C-0.70(\stackrel{\‾}{S}+F+\mathrm{Cr})}{1.87S+0.55A}$

Aluminium-sulfur ratio $\mathrm{Ps}=\frac{A}{S}$

Basicity factor (Cm) generally is controlled at 0.9～1.0, and aluminium-sulfur ratio (Ps) is controlled at 3.5～4.0.In the formula, C, S, A, F, Cr, S thanks to represent CaO in the grog, SiO respectively ₂, Al ₂O ₃, Fe ₂O ₃, Cr ₂O ₃, SO ₃Mass percent, %.

The mineral composition calculation formula of grog is following:

ω(C ₄A ₃S)＝1.99A，ω(C ₂S)＝2.87S，ω(C ₂F)＝2.87F，

ω(CrF)＝1.7Cr，ω(f-SO ₃)＝S-0.131ω(C ₄A ₃S)

ω(f-CaO)＝C-[0.55A+1.87S+0.70(F+Cr+S)]

According to the requirement of grog composition with the rate value, aluminium chromium dosed body refuse: Wingdale: gypsum: the proportioning of modified filler is generally 25%～45%: 30%～45%: 25%～35%: 2%～5%.Batching adopts the on-line automatic feed proportioning system of cement, after grog composition that burns till and rate value are set, proofread and correct batching voluntarily according to the component of raw material and regulates.

The present invention calcines and produces C ₄A ₃S-β-C ₂S calcium sulphoaluminate cement clinker generally adopts dry-process rotory kiln production, also can produce with shaft kiln.The raw material fineness is controlled at 0.080mm square hole sieve screen over-size＜10%.The clinker burning temperature is 1250～1350 ℃, should not surpass 1400 ℃, otherwise CaSO ₄Decompose C ₄A ₃S also decomposes.In calcination process, prevent reducing atmosphere, because reducing atmosphere makes CaSO ₄Resolve into CaS, CaO and SO ₂Calcining temperature should not be too low, then produces too much f-CaO if cross when hanging down, and makes cement with fixed attention anxious, makes C ₂S content reduces.In the sulfoaluminate clinker calcination process, its calcining temperature is low than silicate cement, and it is few liquid phase to occur, mainly is solid state reaction, is difficult for ring formation in the rotary kiln, prevented from caking in the shaft kiln, and the grog grindability is also better.C ₄A ₃S-β-C ₂During S type hydrated cementitious, following reaction takes place:

C ₄A ₃S+2CSH ₂+34H→C ₃A·3CS·H ₃₂+2AH ₃

C ₄A ₃S+18H→C ₃A·3CS·H ₁₂

C ₂S+nH→C-S-H(I)+CH

3CH+AH ₃+3CSH ₂+20H→C ₃A·3CS·H ₃₂

C ₄A ₃S and gypsum form ettringite and Al (OH) ₃Gel, amount of gypsum after a little while, after generate the low sulfur type calcium sulphoaluminate.Because the C that lesser temps forms ₂The S aquation is very fast, generates the C-S-H gel, and AH ₃And C-S-H is gel-filled between the aquation calcium sulphoaluminate, and the structure of reinforcing and fine and close cement stone is so cement early strength is high.Change the incorporation of gypsum in the cement, can make soon do not shrink firmly, microdilatancy, expansion and self-stressing cement.

The main chemical compositions of the aluminate cement grog that the present invention produces is CaO, Al ₂O ₃, SiO ₂, also have Fe ₂O.Reach a spot of MgO, Cr ₂O ₃Deng.Because the difference of raw material and working method, its chemical composition change is very big, and its fluctuation range is following: ω (CaO) 32%～42%; ω (Al ₂O ₃) 36%～55%; ω (SiO ₂)＜9%; ω (Fe ₂O ₃)＜3%; ω (MgO)＜2.0%; ω (R ₂O)＜0.7%.

Al ₂O ₃Be to guarantee to generate low alkalinity CA, CA ₂, C ₁₂A ₇Staple Deng aluminium mineral material.The aluminium chromium dosed slag ratio of patent recycling of the present invention is more suitable.Alumina content is low excessively, C in the grog ₁₂A ₇Increase, cause cement to coagulate soon, strength degradation; Alumina content is too high, too much forms CA ₂, even the CA of non-activity appears ₆, strength of cement particularly early strength descends.

CaO is the basal component that guarantees to generate calcium aluminate.Calcium oxide content is too high, forms C in the grog ₁₂A ₇Cement is coagulated soon; CaO content is low excessively, forms a large amount of CA ₂, early strength descends.In addition, when producing with sintering process, the firing temperature of grog reduces with the increase of CaO content, and firing range also narrows down, and is prone to make ring formation in the kiln.CaO content surpasses at 37% o'clock, material for making clothes stickness caking in the kiln, and operation is difficult to control, and output and quality are lower.

SiO2 can form β-C in high-alumina cement ₂S and C ₂AS.β-C2S sclerosis is slow, C ₂AS does not then have gelling.ω (SiO in the national Specification grog for this reason ₂)≤10%.

Fe in the high aluminium cement clinker ₂O ₃Form the extremely weak C of gelling ₂F, CF can reduce cement intensity.General its content is controlled at and is no more than 3%.

Cr ₂O ₃Fusing point is higher.Mainly with the form exist singly of oxidation state, it does not have gelling in grog.General content is no more than 1%.

Often contain MgCO in the Wingdale ₃A spot of MgO (1%～2%) can quicken the formation of clinker mineral, reduces material melting temperature and liquid phase viscosity.MgO and Al ₂O ₃Reaction generates magnesium-aluminium spinel (MgOAl ₂O ₃), cement quality is descended.MgO content should be less than 2% in the regulation grog in the production.Alkali can make melt temperature reduce, but influential to cement quality, and content surpasses at 0.5% o'clock, can cause that cement coagulates soon, and strength of cement is reduced.P ₂O ₅Content was less than 1% o'clock, and is little to the cement quality influence, surpasses at 1% o'clock, and strength of cement is descended.

When the present invention produces aluminate cement, behind the set grog composition of specification of quality, adopt the online component of manufacture of cement, proportion of raw materials is automatically adjusted, in controlled scope, fluctuate from the NMO correction feed proportioning system.The proportioning that generally contains aluminium chromium slag, Wingdale and other a small amount of modified materials changes in 30%～70%, 65%～30%, 0%～5% scope.For the clinker mineral that obtains being scheduled to is formed, the control of the content of each main oxides in the grog within the specific limits, generally adopt aluminate basicity factor (Am) and alumina silica ratio coefficient as inverse amplification factor value commonly used.

I. aluminate basicity factor Am.Al in the expression high-alumina cement ₂O ₃By CaO saturated degree, promptly

If C, A, S, F, Cr and M represent CaO, Al in the grog respectively ₂O ₃, SiO ₂, Fe ₂O ₃, Cr ₂O ₃Percentage composition with MgO.Except CA, CA ₂Generate C outward, ₂AS, C ₂The amount (by quality ratio) of F, CT CaO that mineral exhaust can calculate the coefficient of the quicklime that each mineral exhausts according to molecular weight.

$\mathrm{Am}=\frac{C-[1.87+0.7(F+T)]}{0.55(A-1.75S+2.53M)}$

Aluminate basicity factor Am representes CA and CA in the grog ₂Relative content.The Am value is high more, representes that promptly CA is many more; The Am value is more little, and CA is few more, and CA ₂Then corresponding increase.When Am=1, the Al in the grog ₂O ₃Except generating C ₂Outside AS and the MA, all the other all generate CA with CaO chemical combination, do not have CA in the grog ₂Exist; When Am=0.5, then aluminate all is CA in the grog ₂And do not form CA.The high-alumina cement Am working control value that China produces is generally 0.72～0.90.Alumina silica ratio coefficient (writing a Chinese character in simplified form into A/S).The alumina silica ratio coefficient is high, and the cement refractory degree that forms in the grog is high; Otherwise liquid phase is many, and refractoriness is low.To low calcium-aluminate refractory cements, A/S often brings up to greater than 16.A/S also has substantial connection with strength of cement.Knowhow proves, A/S＞9.0 o'clock, and the high-alumina cement label can reach No. 425.Aluminium-calcium-rate coefficient (writing a Chinese character in simplified form into A/C).The aluminium-calcium-rate coefficient is high, and firing temperature is high, and the cement setting sclerosis is slow, but refractoriness is high; Otherwise firing temperature is low, and refractoriness is low, and coagulating soon can appear in cement, anxious coagulation phenomena.

After aluminate basicity factor Am and alumina silica ratio coefficient A/S are selected, can carry out charge calculation.When rotary kiln is fuel with heavy oil, can does not have coal ash and mix, with Wingdale and alumina two component charge calculation.As use coal charge to be fuel, then the coal ash incorporation is pressed empirical value and is confirmed.Batching can adopt trial and error method to calculate based on existing experience.

The mineral composition of cement clinker, then can be by following various calculating:

ω(CA)＝1.55(2Am-1)(A-1.7S-2.53M)

ω(CA2)＝2.55(1-Am)(A-1.7S-2.53M)

ω(C2AS)＝4.57S

ω(CRF)＝1.70Cr

ω(MA)＝3.53M

It should be noted that it is to suppose to reach fully under the equilibrium conditions that above-mentioned mineral composition is calculated, the theoretical value of balance crystallization gained; True mineral composition also need be used X ray quantitative analysis and petrographic analysis decision.

Patent aluminate cement of the present invention generally adopts rotary kiln to carry out SINTERING PRODUCTION.Raw material are fired to the fused sintering state in rotary kiln.Generally in oxidizing atmosphere, carry out, impurities in raw materials can not be reduced and remove, thus tighter to the requirement of raw material, contain SiO ₂And Fe ₂O ₃To lack Deng impurity.The sintering range of aluminate cement is narrower, and firing temperature is generally at 1300～1330 ℃.CA promptly begins to form about 900 ℃; C ₁₂A ₇Begin to form at 950～1000 ℃; And CA ₂Begin to form at 1000～1100 ℃.Only 70～80 ℃ of the sintering ranges of grog as long as therefore localized hyperthermia is arranged, are convenient to form bulk, ring formation or are burnt stream.So, produce aluminate cement and can adopt low ash content fuel, control the temperature of clinkering zone well.

The aluminate cement aquation is very fast, adds water 6～12h, promptly can discharge most of hydration heat, and the about 209J/g of 24h hydration heat approaches silicate cement 7d hydration heat.At low temperatures, the responsible hydration heat of high-alumina cement own makes inside concrete keep higher temperature, thereby can bring into play intensity preferably.The hydrated product of high-alumina cement is CAH ₁₀, C ₂AH ₈And aluminum hydroxide gel (AH ₃).Its hydrated product CAH ₁₀, C ₂AH ₈All belong to hexagonal system, formed sheet of crystallization and needle-like crystal are staggered seeks connections with, and overlapping overlap joint can form strong intergrowth of crystals body; Aluminum hydroxide gel (AH ₃) filling in the space of crystalline framework, combined water is big, so voidage is low, so make cement obtain higher physical strength.But behind aquation 5～7d, hydrated product seldom increases, and therefore, the gain in strength at high-alumina cement sclerosis initial stage is very fast, promptly not remarkable later on.Through 1～2 year, particularly intensity can obviously descend under the hygrothermal environment, even can cause Structural Engineering destruction.Its reason is because CAH ₁₀, C ₂AH ₈All be the steady phase that is situated between, can be gradually transformed into more stable C ₂AH ₆, this is a spontaneous process, and quickens along with the raising of temperature.

The aluminosulfate cement that the present invention produced is carried out GB20472-2006 " aluminosulfate cement " standard; The aluminate cement of producing is carried out GB201-2000 " aluminate cement " standard, and the special cement of producing all is superior to the GB index request.

Specific embodiment

The used aluminium chromium dosed slag of patent of the present invention is produced the generation of sodium dichromate 99 process for Jinshi Chemical Industry Co., Ltd., Gansu's calcium-free roasting cleans novel process, and the staple that produces the aluminium chromium dosed slag in January, 2010 to June sees the following form.

Embodiment 1

With getting 3000kg after the aluminium chromium dosed body refuse homogenizing that produces in producing, insert 10m ²Be warming up to 900 ℃ of calcining 3h in the coal gas heating reverberatory furnace, in agitated pool, add water after the taking-up while hot and stir, stir after 30 minutes, with the yellow sexavalent chrome Cr of epipelagic zone ⁶⁺Water is extracted out, send the utilization of chromium salt production system.Again with saturated FeSO ₄.7H ₂O pumps into agitated pool, stirs 30 minutes, with phenylbenzene diamino Cr ⁶⁺Indicator detects, and constant red-purple is explained the completion of detoxifying.Squeeze into the plate-and-frame filter press inner filtration with pump, the filter cake oven dry.

Embodiment 2

Other conditions will rise to 1050 ℃ of calcining 1h in the reverberatory furnace temperature with embodiment 1.

Embodiment 1 sees the following form % with the aluminium body refuse composition that embodiment 2 obtains.

Embodiment 3

Utilize embodiment 1 specification aluminium chromium dosed slag and gypsum and Wingdale to prepare burden, ball mill grinds fineness and is controlled at 0.080mm square hole sieve screen over-size＜10%, and dry method is made a gift to someone in φ 3 * 48m rotary kiln, and 1250 ℃～1350 ℃ calcinings, the grog composition that obtains sees the following form.

The chemical C of grog ₄A ₃S-β-C ₂The S type is represented the composition requirement of quick hardening sulphoaluminate cement cement clinker.

This grog adds 3% gypsum and 8% Wingdale grinding, and the aluminosulfate cement performance index that obtain see the following form.Each item index meets the strength of cement index of GB20472-2006 " aluminosulfate cement " standard, reaches 42.5 grades of labels.

The aluminosulfate cement index of concrete production process sees the following form.

The aluminosulfate cement intensity level

Embodiment 4

Utilize embodiment 2 specification aluminium body refuses and Wingdale to prepare burden; Adding the siliceous clay material therein carries out modified; Ball mill grinds fineness and is controlled at 0.080mm square hole sieve screen over-size＜10%; Dry method is made a gift to someone in φ 3 * 48m rotary kiln, and 1300 ℃～1330 ℃ calcinings, the grog composition that obtains sees the following form.

The main chemistry of grog becomes to meet the requirement of aluminate cement grog composition quality.This grog is directly levigate in ball mill must not be above 10% to 0.080mm square hole sieve screen over-size, and specific surface area must not be lower than 240m ²/ kg just makes aluminate cement, and intensity index sees the following form.Each item index meets GB201-2000 " aluminate cement " standard, reaches 52.5 grades of labels.

The intensity index of high-alumina cement

When being understood that, concerning those of ordinary skills, can improve or conversion, and all these improvement and conversion all should belong to the protection domain of accompanying claims of the present invention according to above-mentioned explanation.

Claims (8)

1. the resource utilization method of an aluminium chromium dosed slag is characterized in that, comprises the steps:

Aluminium chromium dosed slag in the chromium salt production is through high-temperature roasting; Washing separates the salt and the sexavalent chrome of solubility; Soak detoxifcation with the ferrous salt wet method; Again with the aluminium body refuse as raw material production sulplo-aluminate or aluminate special cement.

2. method according to claim 1, aluminium chromium dosed body refuse be at 900 ℃～1050 ℃ high-temperature roasting 1h～3h, makes it be converted into the stable loose shape oxidation state material of dry-matter that is.

3. method according to claim 2 is characterized in that described roasting apparatus is reverberatory furnace, rotary kiln, shuttle kiln or pushed bat kiln.

4. method according to claim 1, said washing are separated the mode that is meant the washing of 60 ℃～80 ℃ water loggings bubbles of employing and are cleaned separation, and wash water gets into the chromium salt production system and utilizes; Preferably, the salt mass percentage content of the solubility after the washing is less than 0.5%.

5. method according to claim 1; Described ferrous salt wet method detoxifcation comprises and being immersed in ferrous sulfate or the solution of ferrous chloride containing sexavalence chromic salts aluminium chromium dosed slag; Hexavalent chromium is reduced to trivalent chromic ion by ferrous radical ion; Aluminium chromium dosed slag after the immersion filters, and gained aluminium body refuse soil uses as the raw material of preparation special cement.

6. method according to claim 5 can drip phenylbenzene diamino indicator and detect the chromic content of solubility in the aluminium chromium dosed slag in reduction process.

7. method according to claim 5, wherein said ferrous iron solution is meant saturated ferrous iron solution.

8. according to any described method of claim 1-8; When the preparation special cement, adopt the online component of manufacture of cement from the NMO correction feed proportioning system; Proportion of raw materials is automatically adjusted, and the proportioning that contains aluminium chromium slag, Wingdale and other modified materials changes in 30%～70%, 65%～30%, 0%～5% scope.