CN105110540A - Recovery treatment method of galvanizing pickling waste hydrochloric acid - Google Patents

Recovery treatment method of galvanizing pickling waste hydrochloric acid Download PDF

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CN105110540A
CN105110540A CN201510537838.9A CN201510537838A CN105110540A CN 105110540 A CN105110540 A CN 105110540A CN 201510537838 A CN201510537838 A CN 201510537838A CN 105110540 A CN105110540 A CN 105110540A
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mother liquor
hydrochloric acid
fecl
feso
acid
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CN105110540B (en
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张宝生
李生
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Xinxing Pipe Casting Group Handan New Materials Co., Ltd.
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Xinxing Ductile Iron Pipes Co Ltd
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Abstract

The invention relates to the technical field of waste acid treatment, and particularly discloses a recovery treatment method of galvanizing pickling waste hydrochloric acid. For a waste acid solution containing hydrochloric acid and FeCl2 with the density of greater than or equal to 1.2 g/mL, the method comprises the following steps: precipitation and filtration, sulfuric acid replacement, crystallization by cooling, crystal vacuum filtration, circular distillation, crystallization by cooling and crystal vacuum filtration, thereby finally obtaining high-purity high-concentration hydrochloric acid and a FeSO4.7H2O crystal, wherein the residual mother solution of the treatment process can be recovered through circular treatment. The method has the advantages of low investment, high treatment efficiency, simple technique, high recovery rate, environment-friendly treatment process, no pollution and favorable economic benefit, and is convenient to operate and easy for maintenance and management.

Description

A kind of recovery and treatment method of zinc-plated pickling waste hydrochloric acid
Technical field
The present invention relates to spent acid processing technology field.
Background technology
Hot dip galvanizing process is one of important means delaying steel corrosion, needs to carry out pre-treatment to steel piece surface, i.e. acid cleaning process with hydrochloric acid before steel part is zinc-plated, by steel piece surface etch in hydrochloric acid, and the rust on removing steel piece surface and oxide film.Iron and steel produces two kinds of molysite in hydrochloric acid during pickling: one is iron trichloride, and one is iron protochloride.Pickling part generally serious get rusty little, mostly what therefore produce is iron protochloride.Along with increasing of molysite, in pickle solution, concentration of hydrochloric acid also can be light, the proportion (density) of pickle solution increases, its corrosion efficiency reduces until lost efficacy gradually, the proportion of general pickle solution reaches 1.2 ~ 1.4(density and is about 1.2g/mL ~ 1.4g/mL) time, namely think and lost efficacy, discard and do not re-use.The hydrochloric acid of near failure is as waste hydrochloric acid, and its main component is FeCl 2, remaining hydrochloric acid and water, if do not process direct discharge, serious environment pollution.Hot dip galvanizing process pickling waste hydrochloric acid treatment process is a lot, and there is corresponding treatment process in each enterprise according to the practical situation of oneself, but conventional the oxidizing roasting method that mainly contains, negative pressure evaporation crystallization process, sulfate substitution method, electrolytic process, Cl 2oxidation style etc.
Oxidizing roasting method to contain FeCl 2spent acid be directly injected in the stove of 600 DEG C, Fe 2o 3discharge from furnace bottom, hydrogen chloride gas enters pickling process behind absorption tower.Its reaction formula is: 4FeCl 2+ 4H 2o+O 2=2Fe 2o 3+ 8HCl.
Negative pressure evaporation crystallization process is that spent acid is pumped into circulating evaporator, and spent acid enters Separation of Water and acid in rectifier after starting evaporation, and concentrated solution low temperature crystallization after evaporation, centrifuge dehydration, product is FeCl 2 .2H 2o (4H 2o).
Above-mentioned two kinds of methods limit by scale, and facility investment and running cost are very high.
Electrolytic process produces Cl by electrolysis NaCl solution 2with NaOH, use Cl 2by the FeCl in spent acid 2be oxidized to FeCl 3, NaOH is imported in spent acid and improves pH value, make FeCl 3precipitate and separate.Although the method facility investment is low, running cost is higher, and energy consumption is high.
Cl 2oxidation style is first will containing FeCl 2remaining hydrochloric acid in spent acid is converted into FeCl 2, then spent acid introduced reaction tower and pass into Cl 2, by FeCl 2be oxidized to FeCl 3, finally will containing Cl 2tail gas alkali lye absorb, make tail gas realize zero release, reduce environmental pollution.The method treating processes does not need heating, and energy consumption is low, and running cost is low.But product FeCl 3economic benefit is very low.
Above-mentioned two kinds of methods all use hypertoxic hazardous gas, and technology controlling and process is complicated, and security risk is higher.
Sulfate substitution method utilizes strong acid to replace weak acid, produces FeSO 4the spent acid treatment process of crystal and hydrochloric acid byproduct.Its reaction formula is: FeCl 2+ H 2sO 4=FeSO 4+ 2HCl, the method facility investment is low, is easy to maintenance management, and running cost is low, three-waste free discharge, and temperature of reactor is less than 100 DEG C.Its product FeSO 4crystal economic benefit is higher.
Galvanized workpiece returns and washes is have significant deficiency to need the galvanized workpiece of secondary galvanization to carry out the technique of pickling again to old galvanized workpiece or quality.The zinc on its main corrosion galvanized workpiece surface.Galvanized workpiece returns acidity when washing and does not require too high, and concentration of hydrochloric acid can wash acid solution as returning at the spent acid of 12% ~ 15%.Carry out galvanized workpiece with hydrochloric acid to return and wash, after repeatedly using, can produce containing high density Zn 2+, lower concentration Fe 2+return and wash spent acid solution.
At home in numerous zinc-plated enterprise, also not do not wash galvanized workpiece be provided with specific pickling region for returning at present.Return when washing and general galvanized workpiece pickling is all a pickling tub, returning the result of washing like this is cause crossed contamination, all containing ZnCl in pickle solution 2with compounds such as ZnO, need to consider Zn in end processing sequences 2+treatment process, and Zn 2+with Fe 2+influence each other, cause spent acid intractability to increase, cost increase.
Summary of the invention
The place that the technical problem to be solved in the present invention is to provide a kind of zinc-plated pickling waste hydrochloric acid reclaims reason method, pickling waste hydrochloric acid is made to wash spent acid solution and do not mix with returning, only pickling waste hydrochloric acid is processed, adopt the treatment process that sulfate substitution method and negative pressure evaporation crystallization process combine, the method technique is simple, without crossed contamination, intractability is low, the rate of recovery is high, easy to operate, cost is low, can by containing hydrochloric acid and FeCl 2waste acidity recovery process, treating processes environmental protection, pollution-free, be easy to maintenance management, and gained byproduct purity is high, good in economic efficiency.
For solving the problems of the technologies described above, the technical solution used in the present invention is: a kind of recovery and treatment method of zinc-plated pickling waste hydrochloric acid, comprises the steps:
Step one, need the galvanized workpiece of pickling to be placed in special pickling tub, with chlorohydric acid pickling, obtain density be more than or equal to 1.2g/mL containing hydrochloric acid and FeCl 2waste acid liquor, reclaim filtration separately, remove solid impurity;
Step 2, by filter after waste acid liquor import closed reactor, detect wherein FeCl 2content, adds the vitriol oil in proportion, occurs to react as follows,
FeCl 2+H 2SO 4=FeSO 4+2HCl,
Sulfuric acid is inexcessive, exothermic heat of reaction, and generation product is FeSO 4supersaturated solution and hydrochloric acid;
Step 3, the solution in closed reactor to be cooled, FeSO 47H 2o crystal starts to separate out, and to 25 DEG C ~ 35 DEG C, immediately cooled solution is imported Suction filtration device suction filtration, obtains FeSO 47H 2o crystal and filtrate, gained filtrate is FeSO 47H 2o saturated solution, filtrate imports mother liquor tank as mother liquor;
During as not being filled with mother liquor in mother liquor tank, also can repeating step one to three again, until be filled with mother liquor in mother liquor tank, then carry out step 4;
Step 4, the mother liquor in mother liquor tank imported in distiller add thermal distillation, be recycled product hydrochloric acid, leave remaining liquid in distiller and import in cooling reactor;
Step 5, remaining liquid to be cooled, FeSO 47H 2o crystal starts to separate out, and to 25 DEG C ~ 35 DEG C, immediately cooled solution is imported Suction filtration device suction filtration, obtains FeSO 47H 2o crystal and filtrate, gained filtrate imports mother liquor tank;
FeCl in step 6, detection mother liquor tank mother liquor 2concentration, if FeCl 2concentration not reach capacity concentration, then mother liquor continues to use in the step 4 of lower batch of waste acid liquor treating processes; If FeCl 2concentration to reach capacity concentration, its treatment process adopts the one in following method A, B:
A, by FeCl 2concentration reach capacity the mother liquor of concentration by the disposal methods of the waste acid liquor after described filtration, namely described step 2 is to step 6;
In B, lower batch of waste acid liquor treating processes, in its step 2, by FeCl 2the reach capacity mother liquor of concentration of concentration import in closed reactor and mix with the waste acid liquor after lower batch is filtered, FeCl in detection mixed solution 2content, adds the vitriol oil in proportion, and sulfuric acid is inexcessive, and all the other steps are identical.
Further, in step one, waste acid liquor precipitates and Filter Press through settling tank successively.
Further, in step 4, distillation temperature is 90 DEG C ~ 95 DEG C.
Further, in step 4, adopt negative-pressure cyclic distillation method, namely in distiller, add mother liquor, when add mother liquor amount to distiller volume 3/4 time, stop interpolation mother liquor, start to add thermal distillation; When in distiller, mother liquor amount drops to 2/3 of distiller volume, distillation completes, and stops heating, and in distiller, remaining liquid imports in cooling reactor; Again in distiller, add mother liquor, repeat above operation, until all mother liquor distillation is complete.
Further, in step 4 during negative-pressure cyclic distillation, in distiller, negative pressure pressure is-0.06MPa.
Further, in step 5, suction filtration carries out at normal temperatures, suction filtration negative pressure pressure-0.04MPa ~-0.06MPa.
Further, the vitriol oil that concentration is 93.3% is added in step 2.
Before waste acid liquor and strong sulfuric acid response, by settling tank and pressure filter, removing the impurity in waste acid liquor, can improve the purity of byproduct, is also that operation is carried out ready smoothly below.
Can produce the recovery product hydrochloric acid of higher concentration in the still-process of step 4, reason has:
1. produce HCl, this part HCl during sulfate substitution and reclaim generation hydrochloric acid;
2. there is portion of residual hydrochloric acid in former spent acid solution, through fractionation by distillation, reclaim and collect;
3.FeSO 47H 2when O crystal is separated out, take away 7 water moleculess, solution solvent is reduced.
Comprehensive above 3 points, in hydrochloric acid soln, solute increases, and solvent reduces, and finally makes to reclaim that product concentration of hydrochloric acid is high, purity is high, can obtain the hydrochloric acid that concentration is about 20%, can directly again use as hydrochloric acid lotion.
Meanwhile, mother liquor Distillation recovery hydrochloric acid, because the boiling point of HCl and water is lower, in negative pressure, be less than 100 degree, thus Heating temperature is low, and energy consumption is low.
Saturated FeSO can be produced in step 5 4solution, separates out FeSO 47H 2the reason of O crystal byproduct has:
1. HCl gas is produced in reaction, reduces solutes content.
2.FeSO 47H 2when O crystal is separated out, take away 7 water moleculess, solution solvent is reduced.
Comprehensive above 2 points, in solution, solute component HCl reduces, and solvent reduces, FeSO 4solution increases, and when the temperature decreases, solubleness reduces, and makes FeSO 4solution is supersaturated solution, last FeSO 47H 2the form of O crystal is separated out.
In the crystallisation by cooling process of step 3 and step 5, due to FeSO 47H 2the solubility with temperature of O crystal reduces and reduces, so FeSO when the temperature decreases 4saturated solution can crystallization.And a small amount of FeCl contained inside solution 2due to the state that do not reach capacity, see FeCl in Fig. 2 2and FeSO 4solubility curve figure, under uniform temp, solubleness FeCl 2compare FeSO 47H 2o high (20 DEG C, FeCl 2solubleness is 62.5g, FeSO 47H 2o solubleness is 48g), so do not have FeCl 2crystal is separated out, a small amount of FeCl 2still stay inside liquid.Thus highly purified FeSO can be obtained 47H 2o is as byproduct, and purity can reach about 98%, and reparation technology is simple, good in economic efficiency.
Adopt the beneficial effect that produces of technique scheme to be: treatment process of the present invention is circulating treatment procedure, accomplishes three-waste free discharge, treating processes environmental protection, pollution-free, energy consumption is low, the replacement(metathesis)reaction gentleness of the vitriol oil and iron protochloride, treating processes safety.Gained reclaims product hydrochloric acid and FeSO 47H 2o purity is high, and the rate of recovery is high, good in economic efficiency.Treatment process of the present invention can by containing hydrochloric acid and FeCl 2waste acidity recovery process, treatment process is simple, and it is convenient to implement, and be easy to maintenance management, input cost is low.
Accompanying drawing explanation
Fig. 1 is process flow sheet of the present invention;
Fig. 2 is FeCl 2and FeSO 4solubility curve figure.
Embodiment
Pickling waste hydrochloric acid is washed spent acid solution and is separated and process with returning by the present invention, pickling waste hydrochloric acid is first through settling tank precipitation and Filter Press, remove solid impurity, adopt sulfate substitution method again, by a large amount of iron protochloride in pickling waste hydrochloric acid and strong sulfuric acid response, generate saturated copperas solution, then through negative pressure crystallization, ferrous sulfate is separated out, obtains byproduct FeSO 47H 2o crystal; Due to FeSO 47H 2the replacement(metathesis)reaction of the precipitation of O crystal and the vitriol oil, make the content of solute HCl increase the Mass lost of aqueous solvent simultaneously, filtrate through distillation, is recycled the hydrochloric acid of product higher concentration again, and this hydrochloric acid can be directly that zinc-plated factory uses; Reclaim with ensureing the object that product is the hydrochloric acid of higher concentration for distillation cost is high, a certain amount of remaining liquid can be remained after distillation, remaining liquid is stored in mother liquor tank, concentration of iron protochloride contained by it, and the different treatment step adding lower batch of pickling waste hydrochloric acid that circulated realizes process.Finally realize whole recyclings of pickling waste hydrochloric acid, realize zero release, free of contamination environmental protection treatment, treating processes is simple, easy to operate, and gained byproduct purity is high, and the rate of recovery is high, good in economic efficiency.
In order to clearly the present invention can be described, provide following specific embodiment and cost analysis contrast:
Embodiment 1
Required equipment: settling tank, pressure filter, spent acid hold-up vessel, mother liquor hold tank, sulfate substitution reactor, cyclic steam water distilling apparatus, cooling reactor, Suction filtration device, vacuum negative pressure device.
Operation steps:
1. sedimentation and filtration
To the galvanized workpiece of pickling be needed to be placed in special pickling tub chlorohydric acid pickling, do not do galvanized workpiece and return and wash technique in pickling tub, pickle solution circulation repeatedly uses until lost efficacy, rule of thumb, it is generally acknowledged that pickle solution proportion reaches 1.2 ~ 1.4, namely think that pickle solution lost efficacy, discarded, as waste acid liquor process.Detect obtain density be greater than 1.2g/mL containing hydrochloric acid and FeCl 2waste acid liquor, reclaim separately.First waste acid liquor is imported in settling tank, when in settling tank, liquid level exceedes certain value, waste acid liquor enters storage pool, remove the impurity solid that in zinc-plated pickling waste hydrochloric acid, particle is larger, again the solution through precipitation is removed impurity by pressure filter press filtration, finally the solid precipitated and filter out is passed through sintering processes.
Sedimentation and filtration, mainly in order to before displacement spent acid, by settling tank and pressure filter, removes the solid impurity in spent acid solution.Reach solid-liquid separation, improve byproduct FeSO 47H 2the purity of O crystal is also that operation is carried out ready smoothly below.
Now waste hydrochloric acid main component in solution is FeCl 2, remaining hydrochloric acid and water.
2. store waste hydrochloric acid
By after press filtration containing hydrochloric acid and FeCl 2waste hydrochloric acid solution import spent acid hold-up vessel, store full 20 tons of aftertreatments.
3. detect the Fe of 20 tons of waste hydrochloric acid liquor in spent acid hold-up vessel 2+(kg/L) content, calculates the vitriol oil amount of adding.
3.1 detect the Fe in spent acid hold-up vessel 2+content
From hold-up vessel, get 10mL sample, detect the Fe in this waste hydrochloric acid solution 2+content, after testing Fe 2+content is 0.115kg/L, and this gravity is 1.4.Processing 4 tons of liquor capacities is 2800L.
3.2 calculate the sulfuric acid amount needing to add in reactor
FeCl 2+H 2SO 4=FeSO 4+2HCl
By calculating, 1L waste hydrochloric acid solution need concentration be 93.3% sulfuric acid 0.201kg, reaction produces hydrochloric acid 0.312kg, produces FeSO 4crystal 0.150kg.
Sulfate substitution reactor volume is 5000L, the waste hydrochloric acid once loaded and sulfuric acid cumulative volume can not calculate according to detected result more than 3500L., primary treatment 2800L waste hydrochloric acid needs the sulfuric acid 562.8kg of 93.3%, and sulfuric acid density is 1.84kg/L, so the volume adding sulfuric acid is 305.8L.Now in reactor, liquid volume is 2800L+305.8L=3105.8L, is less than 3500L.Do not reach retort ld. lmt.
4. replacement(metathesis)reaction
From waste acid pot to the waste hydrochloric acid solution (having poidometer) reactor and import 2800L.Open the agitator of reactor, setting sulfuric acid automatic adding device, imports the sulfuric acid 562.8kg that concentration is 93.3%, carries out replacement(metathesis)reaction, release heat in reaction process in reactor.Primary treatment 2800L spent acid, reacts and has reacted for about 3 hours.
5. crystallisation by cooling
Solution complete for reaction kettle for reaction is imported cooling reactor, the refrigerating unit of reactor is opened, cools, when temperature is cooled to 25 DEG C ~ 35 DEG C, indicate FeSO 47H 2o crystal is separated out, and cool complete, now solution is FeSO 4supersaturated solution.
Required equipment 5000L cooling reactor.Cooling reactor is followed successively by agitator from inside to outside, lined ceramics wall, cooling-cycle device, iron and steel outer wall.
6. negative pressure leaching
Suction filtration device is: suction filtration bucket and vacuum negative pressure device that filter cloth is housed.
Cool complete solution and import suction filtration in suction filtration bucket, carrying out solid-liquid separation, after suction filtration completes, is high purity FeSO in suction filtration bucket 47H 2o crystal, and pack stock.Now final byproduct is FeSO 47H 2o crystal.FeSO after testing 47H 2the purity of O crystal is about 98%.
Suction filtration carries out at normal temperatures, suction filtration negative pressure pressure-0.04MPa ~-0.06MPa.
7. mother liquor stores
Repeat 4-6, the solution gone out by suction filtration imports mother liquor tank as mother liquor and stores, and again focuses on after waiting mother liquor tank to store full 20 tons.
8. circulation distillation
Mother liquor in a certain amount of mother liquor tank is imported in negative-pressure cyclic distiller and distills, the water vapour of volatile matter distillation and HCL gas cooling reclaim, and generate and reclaim product hydrochloric acid.Now in distiller, the main component of solution is a large amount of FeSO 4, micro Fe Cl 2, micro-hydrochloric acid and part water.
Distillation thermal source is the steam of temperature 120 DEG C, actual distillation temperature 90 DEG C ~ 95 DEG C, negative pressure force value-0.06MPa.
In distiller, add mother liquor, when add mother liquor amount to distiller volume 3/4 time, stop interpolation mother liquor, start to add thermal distillation; When in distiller, mother liquor amount drops to 2/3 of distiller volume, distillation completes, and stops heating, and in distiller, remaining liquid imports in cooling reactor; Again in distiller, add mother liquor, repeat above operation, until all mother liquor distillation is complete.
Distilled by negative-pressure cyclic, water vapour, the HCl gas of evaporation are recycled in hydrochloric acid storage barrel by condenser, are 20% through chemically examining this recovery concentration of hydrochloric acid.When being stored into a certain amount of, this product is directly used in zinc-plated pickling.
9. crystallisation by cooling
Remaining liquid imports in cooling reactor and cools, and by observing thermometer, the temperature of solution in Real-Time Monitoring cooling reactor, when temperature is cooled to 25 DEG C-35 DEG C, indicates FeSO 47H 2o crystal is separated out, and cool complete, now solution is FeSO 4supersaturated solution.
10. negative pressure leaching
Suction filtration device is: suction filtration bucket and vacuum negative pressure device that filter cloth is housed.
Cool complete solution and import suction filtration in suction filtration bucket, carrying out solid-liquid separation, after suction filtration completes, is high purity FeSO in suction filtration bucket 47H 2o crystal, and pack stock.Now final byproduct is FeSO 47H 2o crystal.
Suction filtration carries out at normal temperatures, suction filtration negative pressure pressure-0.04MPa ~-0.06MPa.
11. detect FeCl in mother liquor tank 2content
FeCl in real-time detection mother liquor tank 2content, guarantee FeCl 2do not reach capacity state.Owing to containing micro Fe Cl in mother liquor tank 2, the long time integration state that may reach capacity separates out FeCl 2crystal, finally causes byproduct FeSO 47H 2o crystal purity reduces.If FeCl 2do not reach capacity state, continues circular treatment, if FeCl 2reach capacity state, the solution in mother liquor tank imported in reactor and reacts, and calculate according to following methods and need to add H 2sO 4amount:
Now be mainly the FeSO of state of saturation in mother liquor 4the FeCl of solution and state of saturation 2solution.Measure mother liquor sample, add excessive BaCl 2, according to FeSO 4+ BaCl 2=BaSO 4+ FeCl 2, by weighing precipitate B aSO 4content meter calculates FeSO 4in Fe 2+content.Be now a large amount of FeCl in sample 2solution, then detects wherein total Fe 2+content, finally uses total Fe 2+content deducts FeSO 4in Fe 2+content, obtains FeCl in sample 2concentration, i.e. FeCl in mother liquor 2concentration, finally according to FeCl 2+ H 2sO 4=FeSO 4+ 2HCl, calculates the H needing to add 2sO 4amount.
(1) the mother liquor sample in 2 10ml mother liquor tanks is got.
(2) in No. 1 sample, excessive BaCl is added 2solution, causes SO 4 2-react completely.
(3) filter the solution reacted completely, obtain BaSO 4precipitation.
(4) BaSO is dried 4precipitation, weighs.
(5) gained BaSO is used 4feSO in Mass Calculation solution 4content, then learn FeSO 4middle Fe 2+content,
FeSO 4+BaCl 2=BaSO 4+FeCl 2
(6) Fe total in No. 2 samples is detected 2+content.
(7) with total Fe 2+content deduct FeSO 4middle Fe 2+content, be FeCl in original sample 2middle Fe 2+content.
(8) according to calculating FeCl in the original sample learnt 2middle Fe 2+content, calculate need add sulfuric acid amount.
FeCl 2+H 2SO 4=FeSO 4+2HCl
12. repeating steps 8 to 11, until process 20 tons of mother liquors in mother liquor tank.
Do cost analysis with present method and traditional acid-base neutralisation method respectively below, contrast:
(1) present method cost keeping
1. process 2800L spent acid solution, need the sulfuric acid 562.8kg of 93.3%, need steam 1130.4kg, electricity consumption total power 22kw/h, 3 hours consuming time, amount to power consumption 66kw.
Sulfuric acid concentration 93.3%, required sulfuric acid 562.8kg, unit price 0.252 yuan/kg.
Sulphuric acid cost=562.8kg*0.252 unit/kg=141.8 unit.
Steam flow rate 250kg/m 2.s, the 3 hours time (3600s), pipe radius 0.02m, needs steam 1130.4kg, unit price 0.17 yuan/kg.
Steam cost=250kg/m 2.s*3.14*0.02 2* 3600s*0.17 unit/kg=192.168 unit.
Reclaim hydrochloric acid 873.6kg, concentration of hydrochloric acid 20%, unit price 0.02 yuan/kg.
Hydrochloric acid profit=873.6kg*0.02 unit/kg=17.47 unit.
Produce FeSO 4 .7H 2o crystal 240kg, unit price 0.09 yuan/kg.
FeSO 4 .7H 2o crystal profit=240kg*0.09 unit/kg=21.6 unit.
2. all powers of motor:
Hydrochloric acid pump: 4kw/h:
Sulfuric acid pump: 4kw/h:
Evaporation discharging pump: 5.5kw/h
Vacuum tank mother liquor discharging pump: 3kw/h
Filter press pump: 5.5kw/h
Total=4kw/h+4kw/h+5.5kw/h+3kw/h+5.5kw/h=22kw/h
Commercial power unit price 0.7 yuan/degree.
Power consumption expense=22kw/h*3h*0.7=46.2 unit
3. primary treatment 2800L waste acid liquor, actual Meteorological:
Sulphuric acid cost=562.8kg*0.252 unit/kg=141.8 unit.
Steam cost=250*3.14*0.02 2* 3600*0.17=192.168 unit.
Power consumption expense=22kw/h*3h*0.7=46.2 unit
Hydrochloric acid profit=873.6kg*0.02 unit/kg=17.47 unit.
FeSO 47H 2o crystal profit=240kg*0.09 unit/kg=21.6 unit.
Actual Meteorological=input cost-byproduct profit=sulphuric acid cost+steam cost+power consumption expense-hydrochloric acid profit-FeSO 4 .7H 2yuan+192.168 yuan+46.2 yuan-17.47 yuan-21.6 yuan=341.098 yuan, O crystal profit=141.8.
(2) neutralizing treatment method cost keeping:
By calculating, containing FeCl in 1L sample spent acid sample 20.115kg, remains hydrochloric acid 0.0014kg after testing in spent acid.
Neutralisation process is containing FeCl 2waste hydrochloric acid, is stirred by air aeration, dioxygen oxidation Fe 2+for Fe 3+.Then liquid caustic soda neutralization solution hydrochloric acid precipitation Fe is added 3+.
By reaction formula 4FeCl 2+ 4H 2o+O 2=2Fe 2o 3+ 8HCl calculates, containing Fe 2+the 1L sample spent acid sample of 0.115kg, produces Fe 2o 30.164kg, produces HCl0.149kg.
By following reaction formula, calculate precipitation Fe 2o 30.164kg, needs 30% liquid caustic soda 0.246kg, in and HCl0.299kg need 30% liquid caustic soda 0.328kg.
Fe 2O 3+6NaOH=2Fe(OH) 3+3Na 2O
HCl+NaOH=NaCl+H 2O
Process 1L waste hydrochloric acid, adds up to needs 30% liquid caustic soda 0.574kg.Primary treatment 2800L needs 30% liquid caustic soda 1607.2kg.
Primary treatment 2800L waste hydrochloric acid solution, actual Meteorological:
30% liquid caustic soda unit price is 0.625 yuan/kg.
Cost drops into liquid caustic soda=1607.2kg*0.625 unit/kg=1004.5 unit
Cost comparisons to sum up, comprehensive treatment method of the present invention is compared with neutralizing treatment method, and same process 2800L waste hydrochloric acid solution, comprehensive treatment method cost is 341.098 yuan, and neutralizing treatment method cost is 1004.5 yuan.Therefore reduce costs in processing cost, reach the object of cost efficiency, and result is remarkable.

Claims (7)

1. a recovery and treatment method for zinc-plated pickling waste hydrochloric acid, is characterized in that comprising the steps:
Step one, need the galvanized workpiece of pickling to be placed in special pickling tub, with chlorohydric acid pickling, obtain density be more than or equal to 1.2g/mL containing hydrochloric acid and FeCl 2waste acid liquor, reclaim filtration separately, remove solid impurity;
Step 2, by filter after waste acid liquor import closed reactor, detect wherein FeCl 2content, adds the vitriol oil in proportion, occurs to react as follows,
FeCl 2+H 2SO 4=FeSO 4+2HCl,
Sulfuric acid is inexcessive, exothermic heat of reaction, and generation product is FeSO 4supersaturated solution and hydrochloric acid;
Step 3, the solution in closed reactor to be cooled, FeSO 47H 2o crystal starts to separate out, and to 25 DEG C ~ 35 DEG C, immediately cooled solution is imported Suction filtration device suction filtration, obtains FeSO 47H 2o crystal and filtrate, gained filtrate is FeSO 47H 2o saturated solution, filtrate imports mother liquor tank as mother liquor;
During as not being filled with mother liquor in mother liquor tank, also can repeating step one to three again, until be filled with mother liquor in mother liquor tank, then carry out step 4;
Step 4, the mother liquor in mother liquor tank imported in distiller add thermal distillation, be recycled product hydrochloric acid, leave remaining liquid in distiller and import in cooling reactor;
Step 5, remaining liquid to be cooled, FeSO 47H 2o crystal starts to separate out, and to 25 DEG C ~ 35 DEG C, immediately cooled solution is imported Suction filtration device suction filtration, obtains FeSO 47H 2o crystal and filtrate, gained filtrate imports mother liquor tank;
FeCl in step 6, detection mother liquor tank mother liquor 2concentration, if FeCl 2concentration not reach capacity concentration, then mother liquor continues to use in the step 4 of lower batch of waste acid liquor treating processes; If FeCl 2concentration to reach capacity concentration, its treatment process adopts the one in following method A, B:
A, by FeCl 2concentration reach capacity the mother liquor of concentration by the disposal methods of the waste acid liquor after described filtration, namely described step 2 is to step 6;
In B, lower batch of waste acid liquor treating processes, in its step 2, by FeCl 2the reach capacity mother liquor of concentration of concentration import in closed reactor and mix with the waste acid liquor after lower batch is filtered, FeCl in detection mixed solution 2content, adds the vitriol oil in proportion, and sulfuric acid is inexcessive, and all the other steps are identical.
2. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 1, is characterized in that, in step one, waste acid liquor is successively through settling tank precipitation and Filter Press.
3. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 1, is characterized in that, in step 4, distillation temperature is 90 DEG C ~ 95 DEG C.
4. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 1, is characterized in that, adopt negative-pressure cyclic distillation method in step 4, namely in distiller, mother liquor is added, when add mother liquor amount to distiller volume 3/4 time, stop interpolation mother liquor, start to add thermal distillation; When in distiller, mother liquor amount drops to 2/3 of distiller volume, distillation completes, and stops heating, and in distiller, remaining liquid imports in cooling reactor; Again in distiller, add mother liquor, repeat above operation, until all mother liquor distillation is complete.
5. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 4, is characterized in that, in step 4 during negative-pressure cyclic distillation, in distiller, negative pressure pressure is-0.06MPa.
6. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 1, it is characterized in that, in step 5, suction filtration carries out at normal temperatures, suction filtration negative pressure pressure-0.04MPa ~-0.06MPa.
7. the recovery and treatment method of a kind of zinc-plated pickling waste hydrochloric acid according to claim 1, is characterized in that, add the vitriol oil that concentration is 93.3% in step 2.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105439361A (en) * 2016-01-06 2016-03-30 南宁汇安电工设备有限公司 Method and device for waste hydrochloric acid evaporating separation and heat energy multi-time utilization
CN105776139A (en) * 2016-03-16 2016-07-20 江苏双能太阳能有限公司 Waste acid treatment process
WO2018090167A1 (en) * 2016-11-15 2018-05-24 江苏双能太阳能有限公司 Waste acid treatment process
CN108773857A (en) * 2018-08-01 2018-11-09 江苏泰特联合环保科技有限公司 A kind of sulfonation method steel part hydrochloric acid pickling waste liquor recycling treatment process and device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1385377A (en) * 2001-05-10 2002-12-18 东北师范大学 Recycling treatment technology for industrial iron-containing hydrochloric acid wastewater
CN102690010A (en) * 2011-03-24 2012-09-26 镇江市丹徒区江南热镀锌有限公司 Resource integrated utilization and treatment method of hydrochloric acid pickling waste liquid
CN102689930A (en) * 2011-03-24 2012-09-26 镇江市丹徒区江南热镀锌有限公司 Hydrochloric acid pickling waste liquid resource integrated utilization method for preparing iron oxide and ammonium sulfate
CN102757099A (en) * 2012-08-09 2012-10-31 青岛新中基环保科技有限公司 Process for producing high magnetic ferroferric oxide by galvanized pickle liquor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1385377A (en) * 2001-05-10 2002-12-18 东北师范大学 Recycling treatment technology for industrial iron-containing hydrochloric acid wastewater
CN102690010A (en) * 2011-03-24 2012-09-26 镇江市丹徒区江南热镀锌有限公司 Resource integrated utilization and treatment method of hydrochloric acid pickling waste liquid
CN102689930A (en) * 2011-03-24 2012-09-26 镇江市丹徒区江南热镀锌有限公司 Hydrochloric acid pickling waste liquid resource integrated utilization method for preparing iron oxide and ammonium sulfate
CN102757099A (en) * 2012-08-09 2012-10-31 青岛新中基环保科技有限公司 Process for producing high magnetic ferroferric oxide by galvanized pickle liquor

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105439361A (en) * 2016-01-06 2016-03-30 南宁汇安电工设备有限公司 Method and device for waste hydrochloric acid evaporating separation and heat energy multi-time utilization
CN105776139A (en) * 2016-03-16 2016-07-20 江苏双能太阳能有限公司 Waste acid treatment process
WO2018090167A1 (en) * 2016-11-15 2018-05-24 江苏双能太阳能有限公司 Waste acid treatment process
CN108773857A (en) * 2018-08-01 2018-11-09 江苏泰特联合环保科技有限公司 A kind of sulfonation method steel part hydrochloric acid pickling waste liquor recycling treatment process and device
CN108773857B (en) * 2018-08-01 2023-10-13 江苏泰特联合环保科技有限公司 Resource treatment process and device for hydrochloric acid pickling waste liquid of steel product by sulfonation method

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