A kind of preparation method of vanadic anhydride
Technical field
The invention belongs to field of hydrometallurgy, be specifically related to the preparation method of a kind of vanadic anhydride.
Background technology
Along with, in vanadium oxide process for cleanly preparing, the technical barrier that ammonium poly-vanadate precipitation process bulk density is low is hacked, vanadium oxide produces
Quality is greatly improved.But in the preparation technology of existing vanadic anhydride, heat exchanger in precipitation operation preheating process
Frequently fouling blocks so that heat exchanger utilization rate is low, has a strong impact on the production efficiency of vanadic anhydride, in actual production
Journey often skips preheating process, is directly passed through steam heating qualifying liquid in settling tank so that enter the condensed water of precipitation system
Amount significantly increases, and has broken the balance of whole fresh water (FW) system, and after precipitation, upper liquid pH value is relatively low, and the water yield increases after increasing
Cost for wastewater treatment.
For above present situation, in order to solve in existing vanadic anhydride production process the problems such as precipitation pipeline scale, inventor is to heavy
In vanadium operation preheating process, fouling of heat exchangers problem conducts in-depth research.
First the fouling material sample analysis in heat exchanger, finds that it is mainly composed of acid vanadium liquid and occurs to sink in heat exchanger tube
The vanadate that reaction of forming sediment produces.
Then the operation principle of pipe heat exchanger is analyzed.In heat transfer process, acid vanadium liquid flows in tube side, shell
Vanadium liquid in tube side is heated by journey steam by tube wall heat-transfer area.According to the fluid characteristics of motion, acid vanadium liquid is in open circles straight tube
During flowing, at wall, the ripple amplitude of speed is the least, even if in the case of high turbulence, still has a thin layer stream at nearly wall
The flowing of body remains laminar flow form, i.e. laminar sublayer, and its flow velocity is slow, and the long-time steam by about 180 DEG C heats, temperature
Spending height and make acid vanadium liquid generation precipitation, the precipitation of generation is attached to tube wall and forms dirt layer, and accumulation dirt layer is gradually over time
Thicken and finally block pipeline.
Such as, Xichang vanadium factory precipitation operation production process in, the cleaning frequency of heat exchanger run duration be 7~10 days once, clearly
The mode of washing is percussion after artificial unloading, uses giant to rinse, and Russia Tula vanadium factory close with its technique also uses phase
Same cleaning way, all also exists pipeline cleaning cost high, the problems such as vanadic anhydride production efficiency is low, and up to the present,
Have no a kind of and effective solve the method for fouling of heat exchangers problem during acid vanadium liquid precipitation.
Summary of the invention
For above not enough, the technical problem to be solved is to provide one and slows down acid vanadium liquid precipitation fouling of heat exchangers,
The method improving vanadic anhydride production efficiency.
The preparation method of a kind of vanadic anhydride of the present invention, comprises the following steps:
A, effective static mixer pipeline in the pipe heat exchanger of precipitation operation preheating process is replaced, utilize steam heat-exchanging to make acid
Property vanadium liquid temp is risen to 65~75 DEG C by room temperature;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.6~0.9:1, add
Enter ammonium sulfate, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, stirring, regulation pH value be 1.5~2, be steam heated to 90 DEG C~
Boiling, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, wash, dry, calcine, obtain five oxygen
Change two vanadium.
The preparation method of above-mentioned a kind of vanadic anhydride, the main component of wherein said acid vanadium liquid has: TV 20~30g/L, SO4 2-
25~30g/L, P 0.02~0.05g/L, Si 0.13~1.02g/L, Mn 8~12g/L, Mg 0.9~2.5g/L, NH4 +6~8g/L,
And other inevitable impurity on a small quantity.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein said acid vanadium liquid pH is 3~4.
The preparation method of above-mentioned a kind of vanadic anhydride, the mixed cell part of wherein said static mixer pipeline can be SK type,
At least one in SV type, SX type, SL type and SY type.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein in a step and step c, vapor (steam) temperature is 170~190 DEG C.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein regulates the concentrated sulphuric acid that pH value is with 70~98wt% in step c.
The method have the advantages that
(1) the mixed cell structural reform souring vanadium liquid being fixed in static mixer pipeline flow regime in pipe, suppression are utilized
The formation of laminar sublayer, makes acid vanadium liquid rapid dispersion in pipe, and the distribution of each several part solution temperature tends to uniform, slows down dirt layer
Formed;
(2) scale velocity slows down, and reduces heat exchanger and disables cleaning frequency, cleans from one to two weeks and is once reduced to one to two
The moon cleans once, substantially increases the utilization rate of equipment;
(3) heat exchanger is properly functioning, adds quantity of steam needed for hot acid vanadium liquid, decrease the cold of entrance system in reducing settling tank
Condensate flow, often produces the tank ammonium poly-vanadate more original technique of precipitation and can reduce 2~3m3Inflow, has not only saved resource, has also subtracted
Lack and needed wastewater flow rate to be processed;
(4) preheating through heat exchanger, the ammonium poly-vanadate produced in settling tank precipitation bulk density has obtained certain raising.
Accompanying drawing explanation
Precipitation process chart after accompanying drawing 1 improvement;
Accompanying drawing 2 is that (wherein, 1 is adpting flange to SK type static mixer;2 is housing;3 is left-handed dice;4—
For dextrorotation dice).
Detailed description of the invention
The preparation method of a kind of vanadic anhydride of the present invention, comprises the following steps:
A, effective static mixer pipeline in the pipe heat exchanger of precipitation operation preheating process is replaced, utilize steam heat-exchanging to make acid
Property vanadium liquid temp is risen to 65~75 DEG C by room temperature;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.6~0.9:1, add
Enter ammonium sulfate, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, stirring, regulation pH value be 1.5~2, be steam heated to 90 DEG C~
Boiling, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, wash, dry, calcine, obtain five oxygen
Change two vanadium.
When acid vanadium liquid flow in common hollow heat exchange pipeline, no matter flow velocity is how soon, the laminar sublayer at close inside pipe wall without
Method is avoided, and its flowing is maintained as laminar flow form, and flow velocity is slow, will be because of overheated (temperature in the lasting diabatic process of tube wall
Reach more than 90 DEG C) and there is precipitation reaction and then at tube wall incrustation.Static mixer pipeline then can reduce to a certain extent
The generation of fouling, utilizes the mixed cell structural reform souring vanadium liquid being fixed in static mixer pipeline flow regime in pipe,
The formation of inhibition layer laminar sublayer, makes acid vanadium liquid rapid dispersion in pipe, and the distribution of each several part solution temperature tends to uniform, thus subtracts
The formation of slow dirt layer.
The preparation method of above-mentioned a kind of vanadic anhydride, the main component of wherein said acid vanadium liquid has: TV 20~30g/L, SO4 2-
25~30g/L, P 0.02~0.05g/L, Si 0.13~1.02g/L, Mn 8~12g/L, Mg 0.9~2.5g/L, NH4 +6~8g/L,
And other inevitable impurity on a small quantity.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein said acid vanadium liquid pH is 3~4.
The preparation method of above-mentioned a kind of vanadic anhydride, the mixed cell part of wherein said static mixer pipeline can be SK type,
At least one in SV type, SX type, SL type and SY type.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein in a step and step c, vapor (steam) temperature is 170~190 DEG C.
The preparation method of above-mentioned a kind of vanadic anhydride, wherein regulates the concentrated sulphuric acid that pH value is with 70~98wt% in step c.
Below in conjunction with embodiment, the detailed description of the invention of the present invention is further described, the most therefore limits the present invention to institute
Among the scope of embodiments stated.
Embodiment 1
The preparation method of a kind of vanadic anhydride of the present invention, comprises the following steps:
A, precipitation operation preheating process SK type static mixer, utilize the steam heat-exchanging of about 180 DEG C to make acid vanadium liquid temp
65 DEG C are risen to by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump keeps 50Hz constant,
Statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:20g/L, pH value be 3, heat exchanger be batch (-type) use,
The each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.6:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 1.5, steam
It is heated to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
A kind of method preparing vanadic anhydride of the present invention, shown in the precipitation process chart as Figure of description 1 after its improvement;
After improvement, pipe heat exchanger inner tube replaces with the SK type static mixer shown in accompanying drawing 2, and before improving, the inner tube of pipe heat exchanger is
Hollow pipe, does not has any mixed cell in pipe.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 50 days3/ h, heat exchanger tube generation Severe blockage, shadow
Ring production efficiency.
Embodiment 2
The preparation method of a kind of vanadic anhydride of the present invention, comprises the following steps:
A, precipitation operation preheating process SL type static mixer, utilize the steam heat-exchanging of about 180 DEG C to make acid vanadium liquid temp
75 DEG C are risen to by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump keeps 50Hz constant,
Statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:25g/L, pH value be 3.5, heat exchanger be batch (-type) use,
The each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.9:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 2, and steam adds
Heat, to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 46 days3/ h, heat exchanger tube generation Severe blockage, shadow
Ring production efficiency.
Embodiment 3
The preparation method of a kind of vanadic anhydride of the present invention, comprises the following steps:
A, precipitation operation preheating process SY type static mixer, utilize the steam heat-exchanging of about 180 DEG C to make acid vanadium liquid temp
70 DEG C are risen to by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump keeps 50Hz constant,
Statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:30g/L, pH value be 4, heat exchanger be batch (-type) use,
The each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.8:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 1.8, steam
It is heated to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 43 days3/ h, heat exchanger tube generation Severe blockage, shadow
Ring production efficiency.
Comparative example 1
The preparation method of a kind of vanadic anhydride in comparative example 1, comprises the following steps:
In a, precipitation operation preheating process, heat exchanger tube is clean plain hollow pipe, utilizes the steam heat-exchanging of about 180 DEG C to make
Acid vanadium liquid temp is risen to 65 DEG C by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump is protected
Hold 50Hz constant, statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:21g/L, pH value be 3.1, heat exchanger
Using for batch (-type), each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.6:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 1.5, steam
It is heated to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 9 days3/ h, there is Severe blockage in heat exchanger tube,
Affect production efficiency.
Comparative example 2
The preparation method of a kind of vanadic anhydride in comparative example 2, comprises the following steps:
In a, precipitation operation preheating process, heat exchanger tube is clean plain hollow pipe, utilizes the steam heat-exchanging of about 180 DEG C to make
Acid vanadium liquid temp is risen to 75 DEG C by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump is protected
Hold 50Hz constant, statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:25g/L, pH value be 3.5, heat exchanger
Using for batch (-type), each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.9:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 2, and steam adds
Heat, to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 8 days3/ h, there is Severe blockage in heat exchanger tube,
Affect production efficiency.
Comparative example 3
The preparation method of a kind of vanadic anhydride in comparative example 3, comprises the following steps:
In a, precipitation operation preheating process, heat exchanger tube is clean plain hollow pipe, utilizes the steam heat-exchanging of about 180 DEG C
Acid vanadium liquid temp is made to be risen to 70 DEG C by room temperature;By the acid vanadium liquid initial flow > 50m of heat exchanger tube3/ h, the frequency of pump
Keep 50Hz constant, statistics a period of time by the acid vanadium liquid composition of heat exchanger be TV:28g/L, pH value be 3.4, change
Hot device is that batch (-type) uses, and each run time is 3h, and interval time is 3h;
B, the acid vanadium liquid after a step heat exchange is joined in ammonium tank, according to mol ratio, NH4 +: TV=0.8:1, add sulfur
Acid ammonium, stirring, obtain mixed liquor;
C, mixed liquor b step obtained join in settling tank, and stirring and adding concentrated sulphuric acid regulation pH value is 1.8, steam
It is heated to more than 90 DEG C, obtains ammonium poly-vanadate solution;
D, ammonium poly-vanadate solution step c obtained settle, and take ammonium poly-vanadate precipitation, conventionally precipitate ammonium poly-vanadate
Carry out washing, dry, calcine, obtain vanadic anhydride.
By the acid vanadium flow quantity < 15m of heat exchanger tube after producing about 7 days3/ h, there is Severe blockage in heat exchanger tube,
Affect production efficiency.