The manufacture method that has a crystal water sal epsom
The present invention relates to the manufacture method of sal epsom, be used for the manufacture method of the sal epsom that has a crystal water of fertiliser containing magnesium more precisely.
Magnesium can promote the absorption of plant materials to phosphorus, and it is one of indispensable element in the plant materials.Especially magnesium sulfate monohydrate is the torrid zone, the indispensable magnesia fertilizer of subtropics acid soil.Need to use in a large number magnesium sulfate monohydrate in rubber and orchard planting process, only south east asia just needs the magnesium sulfate monohydrate of few hundred thousand tonnes of meter every year.
When the salt manufacturing bittern fully utilizes, a large amount of waste residue high and tow temperature salts will inevitably appear, generally from bittern, reclaim 1 ton of Repone K, need to discharge about 15 tons of high and tow temperature salts.This high and tow temperature salt contains the sal epsom of 25-35% and the sodium-chlor of 25-35%, and contains small amount of impurities such as Repone K, magnesium chloride and bromine.According to the statistics made by the departments concerned, the annual high and tow temperature salt total amount of being discharged in the whole nation is about 400,000 tons, salinization factory generally all is provided with stacks that the place is stacked or water enters the salt ditch after washing away, repeat again to evaporate brine or enter the sea, if repeating to evaporate brine to cause the increase of sal epsom content in the salt, thereby reduced the quality of salt.If enter the waste that resource has been caused in the sea for a long time, polluted environment again, cause vicious cycle.
Chinese patent literature CN1035096A has proposed to produce the method that has two to seven crystal water sal epsom and sodium-chlor with high temp. salt.This method complex process.
Chinese patent literature CN1084138A has also proposed the method that a kind of high temp. salt is separated into Industrial Salt and sal epsom.This method be with high temp. salt primary wash liquor and sulfuric acid by 1: 1-3.0: 0.00001-0.0001 (weight ratio) makes slurry, by settling process it is separated into magnesia magma and high temp. salt tailings, then magnesia magma and water are pressed 1: the proportioning of 0.1-0.2 (weight ratio), mixing makes magnesium sulfate heptahydrate through conversion, and the high temp. salt tail washings generates Industrial Salt more after treatment.Though this processing method has been utilized high temp. salt but complex process, cl content height in the product.
The production that Chinese patent literature CN86105794A proposes has the sal epsom (MgSO of a crystal water
4.H
2O) technology is, will pack in the stoving oven through selected magnisite stone, carries out roasting at 800-900 ℃, roasting 10-15 hour, and generate light calcined magnesia (MgO); The industrial vitriol oil with 98% or 92.5% the industrial vitriol oil are mixed with the sulfuric acid of 70-80% (weight percentage), be preferably 75% sulfuric acid, under agitation adding light calcined magnesia in the sulfuric acid of 40-60 ℃ 70-80%, is 6-7 up to the pH value of reactant.The weight ratio of light calcined magnesia and sulphuric acid soln is 45-55: 100; When reactant dropped to before 50 ℃, the magnesium sulfate monohydrate that generates is pulverized.Though this technology can be made the sal epsom that has a crystal water, this method per unit area yield sulfuric acid consumption is big, consumed again to have the magnesite that higher industrial is worth, and sulfuric acid price straight line rises in the last few years, and supply falls short of demand.Like this, because the rise of the prices of raw and semifnished materials makes the product cost of magnesium sulfate monohydrate surpass the selling price of magnesium sulfate monohydrate, even domestic original magnesium sulfate monohydrate manufacturer is closed down.
Purpose of the present invention just is to work out a kind of manufacture method of new magnesium sulfate monohydrate, reduce sulfuric acid and magnesium oxide consumption, can utilize salinization factory to produce the industrial waste high and tow temperature salt that discharges in the Repone K process again, the sulfuric acid and the magnesian consumption of per unit area yield are reduced greatly, thereby greatly reduce the manufacturing cost of magnesium sulfate monohydrate, and has considerable economic, owing to can utilize the separating magnesium of industrial waste high and tow temperature salt, eliminated its pollution to environment, and have big social benefit, and the simple easy handling of method technology of the present invention.
A kind of manufacture method that has a crystal water sal epsom of the present invention, with sulfuric acid, magnesium oxide, water and from high and tow temperature salt isolated thick (essence) sal epsom (being separating magnesium, smart magnesium again) be raw material; At normal temperatures and pressures thick (essence) sal epsom is fully mixed by certain weight ratio mutually with sulfuric acid, leave standstill to the reactant the content of chlorion and be till the 0-2.5% (weight percentage), magnesium oxide is fully mixed by certain weight ratio mutually with water, (essence) sal epsom slightly: magnesium oxide: sulfuric acid: the ratio of water is 1: 0.060-0.44: 0.078-0.86: 0.011-0.20 (weight ratio), be thick (essence) sal epsom of 0-2.5% again with chloride ion-containing, the vitriolic reactant fully mixes mutually with the mixture of magnesium oxide and water, generates the sal epsom that has a crystal water.
Another kind of the present invention has the manufacture method of a crystal water sal epsom, with magnesium oxide, sulfuric acid and from high and tow temperature salt isolated thick (essence) sal epsom (be separating magnesium again, smart magnesium) be raw material, thick (essence) sal epsom is fully mixed by certain weight ratio mutually with magnesium oxide, add a certain amount of sulfuric acid down in normal temperature and pressure again, after fully mixing, leave standstill in the reactant chloride ion content and be till the 0-2.5%, (essence) sal epsom slightly: magnesium oxide: sulfuric acid: ratio be 1: 0.060-0.44: the 0.078-0.86:(weight ratio), generate the sal epsom that has a crystal water.
Of the present invention another have the manufacture method of a crystal water sal epsom, with sulfuric acid, magnesium oxide, water and from high and tow temperature salt isolated thick (essence) sal epsom (be separating magnesium again, smart magnesium) be raw material, the weight ratio that thick (essence) sal epsom and magnesium oxide ammonium is certain fully mixes mutually, water arrives suitable concentration with Dilution of sulphuric acid, the sulfuric acid that will be diluted with water to suitable concentration at normal temperatures and pressures more under agitation mixes mutually with thick (essence) sal epsom and magnesian mixture, (essence) sal epsom slightly: magnesium oxide: sulfuric acid: the ratio of water is 1: 0.060-0.44: 0.078-0.86: 0.011-0.20 (weight ratio), till the content that leaves standstill chlorion in the reactant after fully mixing is 0-2.5%, generate the sal epsom that has a crystal water.
Of the present invention another have the manufacture method of a crystal water sal epsom, with sulfuric acid, magnesium oxide, water and from high and tow temperature salt isolated thick (essence) sal epsom (being separating magnesium, smart magnesium again) be raw material; Slightly (essence) sal epsom, magnesium oxide, water fully mix mutually by certain weight ratio, at normal temperatures and pressures will thick (essence) sal epsom in stirring down, the mixture of magnesium oxide, water is with after sulfuric acid fully mixes mutually, till the content that leaves standstill chlorion in the reactant is 0-2.5%, (essence) sal epsom slightly: magnesium oxide: sulfuric acid: the ratio of water is 1: 0.060-0.44: 0.078-0.86: 0.011-0.20 (weight ratio) generates the sal epsom that has a crystal water.
The 5th kind of manufacture method that has a crystal water sal epsom will thick (essence) sal epsom be stirred well to mutually by certain weight ratio with certain density sulfuric acid that chloride ion content can obtain qualified product to 0-2.5% through heat drying in the reactant.
Thick (essence) sal epsom as the inventive method is thick (essence) sal epsom that high and tow temperature salt is drawn by separation, to contain the sal epsom 50-80% that has a crystal water in thick (essence) sal epsom for well.
Contain magnesium oxide greater than 80% in the said magnesium oxide, to contain magnesium oxide 80-90%, better to contain magnesium oxide 85-90% again for well.Magnesian content is high more good more in the magnesium oxide, but magnesian content is high more, and the Costco Wholesale of raw material increases.Said magnesium oxide is wherein a kind of of magnesia (being causticity magnesia, magnesia, causticity magnesite or magnesium oxide again), light calcined magnesia, heavy-calcined magnesia, chemical pure magnesium oxide among the present invention.Said magnesia is that (magnesiumcarbonate MgCO3) places straight formula, rotary or other kilns, a kind of product of finely disintegrated behind 800-850 ℃ temperature lower calcination with magnisite.
Sulfuric acid used in the method for the present invention can be used industrial sulphuric acid, also can use industrial waste sulfuric acid, but used sulfuric acid concentration is greater than 80% when feeding intake (weight percentage, down with), is advisable with the sulfuric acid of 80-98% again.
Used water is tap water.
All in the method for the invention stirrings, its effect is that raw material is mixed, the quality of stirring velocity and product does not have any relation.
A kind of analytical procedure of chlorion is to be titrating solution with the silver nitrate solution in the reactant, is indicator with the potassium chromate solution, carries out titration down with silver nitrate solution color draws the content of chlorion not till the leg until light red brown suspension liquid occurring shaking.The analytical procedure of another kind of chlorion is to be titrating solution with Mercury pernitrate solution, is indicator with the natrium nitroferrocyanatum, and titration is a terminal point to insoluble nitrosyl iron mercury cyanide white precipitate occurring, draws chloride ion content.
The advantage that has the manufacture method of a crystal water sal epsom of the present invention is:
1. method technology of the present invention is simple, and energy consumption is low, constant product quality, solvable content of magnesia is not less than 26% in the sal epsom of producing that has a crystal water, and sulphur content is not less than 20%, and calcium oxide is not higher than 2%, free acid is not higher than 0.5%, meets export standard fully.
2. processing method of the present invention is owing to utilized isolated thick (essence) sal epsom from the waste material high and tow temperature salt that salinization factory discharges, eliminated the high and tow temperature salt environmental pollution, and reduced sulfuric acid and magnesian consumption, greatly reduce the production cost of magnesium sulfate monohydrate.
With following embodiment the manufacture method that has a crystal water sal epsom of the present invention is further described; to help understanding to invention and advantage thereof; and not as the qualification to protection scope of the present invention, protection scope of the present invention is decided by claim.
Embodiment 1
Present embodiment (is separating magnesium, smart magnesium again with isolated thick (essence) sal epsom that contains the sal epsom of 76.69% 1 crystal water from high and tow temperature salt, produce in saltern, Tanggu), 80% sulfuric acid is raw material with the magnesia (magnesium oxide) and the water that contain magnesium oxide 82.5%.
Thick (essence) sal epsom (being separating magnesium, smart magnesium again) that at normal temperatures and pressures 1 ton (1000 kilograms) is contained 76.69% 1 crystal water sal epsom, 200 kilogram 80% sulfuric acid fully mixes mutually, leaves standstill till the content to 1.23% (weight percentage) of chlorion to the reactant; The water that will contain 66 kilograms of 82.5% magnesian magnesias and 200 kilograms fully mixes; Thick (essence) sal epsom, vitriolic reactant with chloride ion-containing to 1.23% fully mixes mutually with the mixture of magnesium oxide and water again, contain solvable magnesium oxide 28.01% in the sal epsom that has a crystal water that generates, sulphur content 22.46%, containing calcium oxide is 0.21%, and containing free sulfuric acid is 0.02%.
Embodiment 2
Present embodiment is with isolated thick (essence) sal epsom (being separating magnesium, smart magnesium again) that contains 72.24% 1 crystal water sal epsom from high and tow temperature salt, 80% sulfuric acid and to contain magnesium oxide be that 90% magnesium oxide is raw material.
At normal temperatures and pressures with 1 ton from high and tow temperature salt isolated thick (essence) sal epsom that contains the sal epsom of 72.24% 1 crystal water fully mix mutually with 0.1 ton of magnesium oxide that contains magnesium oxide 90%, add down 0.2 ton of 80% sulfuric acid in normal temperature and pressure again, after fully mixing, leave standstill till the content to 1.06% of chlorion to the reactant; Contain solvable magnesium oxide 26.8%, sulphur content 20.3%, calcium oxide 0.45%, free sulfuric acid 0.25% in the sal epsom that has a crystal water that generates.
Embodiment 3
Present embodiment is with isolated thick (essence) sal epsom (being separating magnesium, smart magnesium again) that contains 71.23% 1 crystal water sal epsom from high and tow temperature salt, 80% sulfuric acid and to contain magnesium oxide be that 83.5% magnesia (magnesium oxide) and water are raw material.
1 ton of thick (essence) sal epsom that contains 71.23% 1 crystal water sal epsom is fully mixed mutually with 0.33 ton of magnesia that contains magnesium oxide 83%, with the Dilution of sulphuric acid of 200 kg of water with 0.73 ton 80%, again the sulfuric acid of dilute with water is under agitation mixed mutually with the mixture of thick (essence) sal epsom and magnesia at normal temperatures and pressures, after fully mixing, the content that leaves standstill chlorion in the reactant is till 0.40%; Generation has in the sal epsom of a crystal water and contains solvable magnesium oxide 26.1%, sulphur content 20.18%, calcium oxide 0.21%, free sulfuric acid 0.35%.
Embodiment 4
Present embodiment is with isolated thick (essence) sal epsom (being separating magnesium, smart magnesium again) that contains 72.39% 1 crystal water sal epsom from high and tow temperature salt, 83% sulfuric acid, and containing magnesium oxide and be 84.5% magnesia (magnesium oxide) and water is raw material.
1 ton of thick (essence) sal epsom and 0.15 ton of magnesia and 0.1 ton of water that contains magnesium oxide 84.5% that contains 72.39% 1 crystal water sal epsom is fully mixed, at normal temperatures and pressures will thick (essence) sal epsom and the mixture of magnesia and water with after 0.3 ton 83% sulfuric acid fully mixes mutually, leave standstill till the content to 0.97% of chlorion in the reactant; Generation has in the sal epsom of a crystal water and contains solvable magnesium oxide 27.01%, sulphur content 21.8%, calcium oxide 0.9%, free sulfuric acid 0.19%.