CN101624196A - Hydrochloric acid-ammonium salt circulation method phosphorite comprehensive utilization clean production technology - Google Patents

Abstract

The invention relates to three kinds of inorganic chemical product joint production technology, in particular to hydrochloric acid-ammonium salt circulation method phosphorite comprehensive utilization clean production technology. The process comprises the following steps that: 1, magnesium chloride undergoes hydrothermal reaction in a refining mode to obtain a high-quality MgO product and HCl gas as a byproduct; 2, the HCl gas is eluted by phorphorite slurry, undergoes acidification reaction and is subjected to liquid-solid separation and sand removal to obtain CaCl2 and H3PO4 as main acid hydrolyzates; 3, CaCl2 liquid and H3PO4 liquid are separated by a solvent extraction method; 4, the CaCl2 liquid and (NH4)2CO3 liquid are purified and undergo double decomposition reaction to obtain an ultrafine CaCO3 product and a NH4Cl byproduct; 5, ammonium chloride liquid is added to light burnt MgO; the mixture undergoes ammonia evaporation reaction; the evaporated NH3 is eluted by cold water; and CO2 is filled to obtain regenerated ammonium carbonate for circulation in the step four; 6, the residual liquid of the evaporated ammonia is subjected to fine filtration, purification and condensation to obtain refined MgCl2 for use in the step one; 7, H3PO4 obtained in the step three is purified and condensed to obtain a hydrochloric acid product; and 8, if nitric acid and hydrofluoric acid are used to replace the hydrochloric acid in the reaction, a process is similar to the process of the technology and is unnecessary to give details.

Description

Hydrochloric acid-ammonium salt circulation method phosphorite comprehensive utilization clearer production technology

(1) technical field

The present invention relates to three kinds of inorganic chemical product combination producing technology, be specifically: hydrochloric acid---ammonium salt circulation method phosphorite comprehensive utilization clearer production technology.

(2) technical background

China produced 3,700 ten thousand tons of phosphorus ores in 2006, and phosphorus chemical product is crossed ten million ton, is ultra-large type chemical industry industry.Production method is multiple, but main flow only two kinds of electric heating process yellow phosphorus and phosphoric acid by wet processes.

Electric heating process yellow phosphorus, quality better is convenient to long-distance transport.Average power consumption 1.5 ten thousand degree of 1 ton of yellow phosphorus of fatal shortcoming, high energy consumption, expensive can only be used rich ore; Yellow phosphorus average emission 8-10 ton slag per ton, 3,000 NM ³Waste gas, 0.5 ton of toxic phosphorus mud and a large amount of heat energy.Though slag can be made cement, waste gas can be made carbonated product, the recyclable phosphorus of phosphorus mud, and used heat is also recyclable, and investment is big, and profit is thin, and little factory does not rise, and factory is reluctant to do greatly, and there is the factory of tame yellow phosphorus more than 140 in the whole nation, and government advocates for many years, there how many families are dried to become? So developed country's phosphorus production is in rapid atrophy in recent ten years, Chinese yellow phosphorus industry tenfold rises suddenly and sharply simultaneously, is once accounting for global production capacity 85%.Country realizes the truth finally, by rising last year, cancel the electricity price preferential policy of high consuming electric power, the yellow phosphorus export tax rebate changes into adds 20% outward, and policy guidance is obvious, the energy appreciates in addition, rich phosphorus ore shortage, environmental protection pressure is big, the wet phosphoric acid refining rapid technological improvement, long-range seeing, China's electric heating process yellow phosphorus is gone from bad to worse only sooner or later.

The wet processes phosphorus ore takies ore deposit more than seventy percent, and national producer is over thousands of, and almost 100% is sulfuric acid process, and method is simple, less energy-consumption, and low cost, output are very big, and last year, homemade sulfuric acid was more than 5,000 ten thousand tons, more than halfly was used for this.China's a lack of sulfur, half sulphur causes the sulfuric acid price to be ascended to heaven by import.China is large agricultural country, and the soil lacks phosphorus mostly, and agricultural accounts for phosphor resource with phosphate fertilizer and consumes 80%, and is indispensable, can't substitute.Though China is the second in the world phosphor resource big country, announce that still phosphorus ore belongs to one of 20 kinds of short resources after 2010.Phosphorus ore and sulfuric acid hybrid reaction are used in domestic wet method phosphorus ore processing mostly, simply make after the slaking to contain P ₂O ₅Low and calcium superphosphate product that be regardless of with phosphogypsum, its transportation and sales at a distance, low grade.The rich phosphorus ore water of another kind of usefulness adds sulfuric acid reaction, and filtering phosphogypsum slag gets phosphoric acid, makes after the purification to contain P ₂O ₅High high-quality phosphorus potassium, ammophos or other phosphorus chemical products, this method production technology day essence because of cost is low, enlarges scale day by day.Existing problems are to use rich ore, and inadequate resource, domestic rich ore only account for 1/5 and permitted, and contain P ₂O ₅Be lower than 18% lean ore account for reserves half, and difficult ore dressing enrichment.1 ton of P of the every product of this method ₂O ₅6 tons of phosphogypsums of average attached product.Though can make the attached product cement of sulfuric acid, with the iron acid of sulphur, lime cement made of stones is incomparably than advantage, and the comprehensive utilization phosphogypsum is difficult to launch.

In a word, generally speaking the wet phosphate production of China face rich phosphorus ore shortage at present, and sulfuric acid appreciates, environmental protection pressure three big crises, and worldwide grain shortage will significantly increase the phosphate fertilizer demand.How to tackle, be the thing of industry headache, is the prime mover that the present invention produces.

Phosphorus ore contains P ₂O ₅Outside contain CaO and Wingdale is about the same, contain part fluorine composition, can fully utilize? can external salt acid system, the nitrate method wet phosphate technology that early has be improved? the hydrochloric acid cyclic method that early has, nitric acid circulation method be the sour reusable edible of part only, all recycles? the sixties in last century, Israel was because of no sulfuric acid, with hydrochloric acidolysis phosphorus ore, extracting and separating CaCl ₂With H ₃PO ₄The IMI method, why CaCl ₂Abandon? CaCl ₂The renewable hydrochloric acid of hydrothermal decomposition, attached product CaO added value is too low, and the pyrolysis temperature height, and energy consumption is big, and is unfavorable.If CaCl ₂Add volatile salt after the purification, can get ultra-fine (nanometer) CaCO ₃The big appreciation, attached product ammonium chloride adds light-burned MgO, and ammonia still process, purification will be made with extra care MgCl ₂The hydrothermal decomposition hydrochloric acid of must regenerating simultaneously, obtains costly high-quality MgO product, and hydrothermal temperature is low, and energy consumption is low.The regeneration of hydrochloric acid process becomes light-burned MgO precision work process, and ammonia reclaims and adds CO ₂Make volatile salt regeneration.Each operation early has, and is the integrated reorganization of the ready-made operation of different industries in essence, again with reference to the U.S., Yugoslavia, Russia once with extracting technologies such as uranium, thorium, rare earth in hydrochloric acid, the nitrate method phosphorus ore, the present invention has produced.Its whole beyond example, but per step all be ready-made technology, operating parameters has entirely, no technical risk.Its comprehensive utilization of resources rate height, energy-conservation outstanding, " three wastes " of traditional technology become Triratna, and energy-conservation pollution treatment reduction of discharging and high added value obtain synchronously, low product phosphorus ore profit in can directly utilizing, powerlessness supply pressure.Three kinds of produce market capacity are especially big, and output and demand mate substantially, and the traditional technology four problems is readily solved, if the industrialization demonstration is gone into operation and continued to optimize, is expected to adopt for industry rapidly, and the phosphorus chemical industry revolution obtains new approaches.

(3) summary of the invention

Technology of the present invention is: 1, ground phosphate rock carefully arrives-100～-200 orders, becomes ore pulp with water 1: 1～1.5 ratios; 2, refining MgCl ₂6H ₂O goes into indirect calcining rotary furnace 〉=550 ℃, hydro-thermal reaction: MgCl between best 800～900 ℃ ₂+ H ₂O → MgO+2HCl ↑, reaction is fast and thoroughly, calcining is to be MgO product high-quality indirectly, and HCl gas concentration height does not have steam because of furnace charge inverse motion discharging section in addition, should spray into water vapour, short reaction, the controlled little air that enters down adds and reacts: MgCl ₂+ 1/2O ₂→ MgO+Cl ₂↑, produce some strong oxidizing property chlorine simultaneously, better; 3, inhale HCl gas with phosphorus ore slurry circulated in countercurrent spray, carrying out the acidolysis ore pulp is thermopositive reaction, and controlled temperature is when looking into ore pulp and contain free HCl at 0.4～0.6N between 80～90 ℃, and visual acidolysis is up to standard, discharges.The reaction vent gas reclaims CO through potash water liquid ₂And emptying behind the fluoro-gas.Emit the acidolysis ore pulp, the filtering silt particle, the winner contains CaCl ₂With H ₃PO ₄And the acid hydrolysis solution of free HCl; 4, with similar extraction agents of other extraction ability such as propyl carbinol, primary isoamyl alcohol or tributyl phosphates, with the extraction of IMI method, back extraction makes CaCl ₂With H ₃PO ₄Liquid separates; 5, CaCl ₂Liquefaction is learned and is purified, and belongs to conventional art, does not carefully state control CaCl ₂Concentration is between 3～3.5M/L, with (the NH of excessive 10～15%3M/L ₄) ₂CO ₃Liquid pumps into supergravity reactor or high-speed mixer under 40～50 ℃, or the clarifixator internal reaction, and necessity can add crystal control agent, and reaction can obtain ultra-fine (nanometer) CaCO ₃Product, pure water is clean, dry, gets commodity lime carbonate, and attached product contains NH ₄The female water of Cl; 6, NH ₄The female water of Cl adds light-burned MgO, and aquation between 80～100 ℃ makes MgO become Mg (OH) ₂, make Mg (OH) in the mixing ₂With 2NH ₄Cl molecular ratio excessive 1.5～3% is gone into ammonia still, can finish ammonia still process fast under column bottom temperature 〉=120 ℃, and cat head is discharged NH ₃, CO ₂Gas is mended CO again ₂, water drench reclaim regeneration (NH ₄) ₂CO ₃The liquid circulation is used; 7, the surplus liquid of ammonia still process is refining, referring to another invention of the inventor " ammonium circulation method high-purity MgO, Mg (OH) ₂, MgCO ₃Production technology " just the same, make high-purity MgCl ₂Go into 2 reactions after concentrating, circulation is finished; 8, the raw phosphoric acid that obtains is with tributyl phosphate (TBP) or other similar performance extraction agent extraction, back extraction, concentrate and can make phosphoric acid purification reach food grade.But 80% makes fertilizer, and purification can simply be carried out, and gets purifying phosphoric acid, deep processing becomes multiple phosphorus chemical product, wherein only needs small amounts of phosphoric acid and KCl or NaCl reaction, gets potassiumphosphate (sodium), attached product high-quality hydrochloric acid just can satisfy and transfer PH and replenish loss hydrochloric acid in this technological cycle simultaneously.So, although on the ground of traffic difference, using this method, needn't worry about for transportation hydrochloric acid; 9, replace hydrochloric acid, resemble process with nitric acid, hydrofluoric acid in the above-mentioned technology.If nitric acid is convenient inexpensive, the nitrification ore pulp is as cold as-5～-15 ℃ after the smart filter, makes 70～80% nitrocalcite Crystallization Separation, obtains mother liquor again with TBP or MIBK-toluene extracting and separating, can simplify technology.Nitrate method is to the higher phosphorus ore aerobic of organism decolorization in addition; The aforementioned salt acid system, pyrolysis MgCl ₂, add little air and produce some Cl ₂Ore pulp oxidative decoloration and oxidation precipitation iron, manganese effect are also arranged, can economize oxidation reinforced dose.

After the low grade ore coarse crushing, permeate leaching, dump leaching, drill traverse with hydrochloric acid and obtain solution to produce the said products method similar.

Claims (8)

1, refining MgCl ₂6H ₂O goes into indirect calcining rotary furnace 〉=550 ℃, hydro-thermal reaction: MgCl between best 800～900 ℃ ₂+ H ₂O → MgO+2HCl ↑, reaction is fast and thoroughly, calcining is to be MgO product high-quality indirectly, and HCl gas concentration height does not have steam because of furnace charge inverse motion discharging section in addition, should spray into water vapour, short reaction, the controlled little air that enters down adds and reacts: MgCl ₂+ 1/2O ₂→ MgO+Cl ₂↑, produce some strong oxidizing property chlorine simultaneously, better.

2, inhale HCl gas with phosphorus ore slurry circulated in countercurrent spray, carrying out the acidolysis ore pulp is thermopositive reaction, and controlled temperature is when looking into ore pulp and contain free HCl at 0.4～0.6N between 80～90 ℃, and visual acidolysis is up to standard, discharges.The reaction vent gas reclaims CO through potash water liquid ₂And emptying behind the fluoro-gas.Emit the acidolysis ore pulp, the filtering silt particle, the winner contains CaCl ₂With H ₃PO ₄And the acid hydrolysis solution of free HCl.

3, with similar extraction agents of other extraction ability such as propyl carbinol, primary isoamyl alcohol or tributyl phosphates, with the extraction of IMI method, back extraction makes CaCl ₂With H ₃PO ₄Liquid separates.

4, CaCl ₂Liquefaction is learned and is purified, and belongs to conventional art, does not carefully state control CaCl ₂Concentration is between 3～3.5M/L, with (the NH of excessive 10～15%3M/L ₄) ₂CO ₃Liquid pumps into supergravity reactor or high-speed mixer under 40～50 ℃, or the clarifixator internal reaction, and necessity can add crystal control agent, and reaction can obtain ultra-fine (nanometer) CaCO ₃Product, pure water is clean, dry, gets commodity lime carbonate, and attached product contains NH ₄The female water of Cl.

5, NH ₄The female water of Cl adds light-burned MgO, and aquation between 80～100 ℃ makes MgO become Mg (OH) ₂, make Mg (OH) in the mixing ₂With 2NH ₄Cl molecular ratio excessive 1.5～3% is gone into ammonia still, can finish ammonia still process fast under column bottom temperature 〉=120 ℃, and cat head is discharged NH ₃, CO ₂Gas is mended CO again ₂, water drench reclaim regeneration (NH ₄) ₂CO ₃The liquid circulation is used.

6, the surplus liquid of ammonia still process is refining, referring to another invention of the inventor " ammonium circulation method high-purity MgO, Mg (OH) ₂, MgCO ₃Production technology " just the same, make high-purity MgCl ₂Go into 2 reactions after concentrating, circulation is finished.

7, the raw phosphoric acid that obtains is with tributyl phosphate (TBP) or other similar performance extraction agent extraction, back extraction, concentrate and can make phosphoric acid purification reach food grade.But 80% makes fertilizer, and purification can simply be carried out, and gets purifying phosphoric acid, deep processing becomes multiple phosphorus chemical product, wherein only needs small amounts of phosphoric acid and KCl or NaCl reaction, gets potassiumphosphate (sodium), attached product high-quality hydrochloric acid just can satisfy and transfer PH and replenish loss hydrochloric acid in this technological cycle simultaneously.So, although on the ground of traffic difference, using this method, needn't worry about for transportation hydrochloric acid.

8, replace hydrochloric acid, resemble process with nitric acid, hydrofluoric acid in the above-mentioned technology.If nitric acid is convenient inexpensive, the nitrification ore pulp is as cold as-5～-15 ℃ after the smart filter, makes 70～80% nitrocalcite Crystallization Separation, obtains mother liquor again with TBP or MIBK-toluene extracting and separating, can simplify technology.Nitrate method is to the higher phosphorus ore aerobic of organism decolorization in addition; The aforementioned salt acid system, pyrolysis MgCl ₂, add little air and produce some Cl ₂Ore pulp oxidative decoloration and oxidation precipitation iron, manganese effect are also arranged, can economize oxidation reinforced dose.