Centrifugal extraction machine with acid and alkali waste water in the chemical manufacturing production
Acid and alkali waste water is one of the most common wastewater treatment.
Acidic waste water mainly from steel mills, chemical plants, dye factory, electroplating factory and mine etc, waste water treatment to key management contains a variety of harmful substances or heavy metal salts.
Acid in wastewater quality score difference is very big, the low of less than 1%, higher than 10%.
Alkaline wastewater mainly comes from dyeing factory, tanneries, paper mills, oil refineries, etc.
Wastewater treatment, will encounter containing organic alkali or containing inorganic base.
The mass fraction of alkali is higher than 5%, less than 1%.
Acid and alkali waste water, in addition to containing acid and alkali, often contain acid salt, alkali salt and other inorganic and organic matter.
with strong corrosion resistance, acid and alkali waste water, such as directly discharge without governance, corrosion pipe canal and structures;
Discharged into water bodies, change the pH of the water, interference, and affect the growth of aquatic and fishery production.
Into farmland, will change the nature of the soil, the soil acidification or salinity, harm crops;
Acid and alkali raw material loss and waste.
Acid and alkali wastewater should be recycled as far as possible, so or processed, wastewater pH 6 ~ 9 in between, can be discharged into water body.
the general principles of the acid and alkali waste water treatment is: (
High concentration of acid and alkali waste water, priority should be recycled wastewater treatment method, according to different water quality, water quantity and technical requirements, factory or regional scheduling, try to reuse: such as repetitive use have difficulty, or the concentration is low, water amount is larger, can use concentrated wastewater treatment method of recovery of acid and alkali.
Low concentration of acid and alkali waste water, such as pickling tank cleaning water, alkaline cleaning tank rinse water, waste water treatment should be.
for neutralization process, should be treated first consider the principle of wastewater treatment.
Such as acid and alkali waste water neutralization or using waste alkali (
Neutralizing acidic waste water, the use of waste acid and alkaline waste water.
Without these conditions, can use neutralizer wastewater treatment.
high concentration of acid and alkali waste water recycling for high concentration of acid (
In more than 10%)
, containing alkali (
In more than 5%)
Wastewater, first of all should according to different water quality, water quantity and technical requirements, factory or regional scheduling, try to reuse;
Such as reuse with difficulty, or concentration is low, water amount is larger, can adopt the method of enrichment recycling alkali.
the acid waste water recycling methods mainly include: machine centrifugal extraction solvent extraction, submerged combustion temperature crystallization, vacuum concentration freezing crystallization and natural crystallization method.
the basic process of submerged combustion heat of crystallization method is: will the gas burning hot gas produced by direct injection for evaporation of the liquid waste, remove the moisture in the waste liquid, enrichment and recovery of acid.
The enrichment method suitable for a large number of wastewater treatment, its advantage is high thermal efficiency, recycling of regenerated acid concentration is higher,
Up to 42.
Defect is acid mist, anticorrosion demand is higher, and shall be combustible gas source.
the basic process of vacuum concentration and natural crystallization method is: using the method of vacuum pressure reduce the boiling point of the wastewater containing acid, moisture to evaporate, enrichment and recovery of acid.
The enrichment method has the advantage of high degree of automation, acid mist problem easy to solve;
The disadvantage is that the recycling regenerative acid concentration is low,
For only 18 ~ 20%)
More in need acid corrosion resistant material and equipment investment is larger.
natural crystallization method is mainly used acid wastewater from ferrous sulfate, ammonium sulfate and other chemical raw materials and chemical fertilizer.
In addition, still can use dialysis method, ion exchange method, recovery of acid, alkali substances.
In water treatment process, and acidic waste water can be used for water softening regeneration of sulfonated coal and used for water quality stability.
machine centrifugal extraction solvent extraction using compounds in two mutually combination (
Or slightly soluble)
Solubility in solvent or the distribution coefficient of the different, make the compounds from within a solvent to another solvent.
After repeated many times extraction, to pick up the most of the compounds is normal temperature operation, save energy, does not involve the use of solid, gas, easy to operate.