CN1331749C

CN1331749C - Tech. for ammoniating integration of acid material fluidifying

Info

Publication number: CN1331749C
Application number: CNB2004100402877A
Authority: CN
Inventors: 朱家骅; 周勇; 夏素兰; 杨雪峰; 曹丽淑; 程远贵
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2004-07-23
Filing date: 2004-07-23
Publication date: 2007-08-15
Anticipated expiration: 2024-07-23
Also published as: CN1724367A

Abstract

The present invention relates to a method for producing granular compounds containing ammonium through gas-liquid-solid three-phase reactive crystallization in fluidized beds. The present invention has the main technical characteristic that under the condition that the moisture content of acid materials in fluidized beds is from 1 to 12% (wt%), reaction media is distributed evenly, reaction is carried out through surface contact, dryness is carried out through self-heating, and the combined operation of reaction, granulation and dryness is completed by one step. The present invention has the advantages of no need of granular recycled materials, even granularity of products and no adhesion. Compared with the prior art, the present invention also has the advantages of obviously shortened flow path, compact device, large production intensity, low power consumption, and little and concentrated tail gas quantity. Granular compounds containing ammonium can be produced from various acidic materials by the method of the present invention, such as production of diammonium phosphate from monoammonium phosphate, production of ammonium calcium phosphate from heavy calcium, production of potassium ammonium phosphate from potassium hydrogen phosphate, etc.

Description

Acid goods fluid ammonification integrated approach

Technical field the present invention relates to the crystals dried integrated approach of a kind of acid goods fluid bed aminating reaction, from multiple acid material production particulate state ammonium-containing compound, as: from monoammonium phosphate production diammonium phosphate, produce ammonium phosphate calcium, produce potassium-ammonium phosphate from potassium hydrogen phosphate from coarse whiting.

The technology of the existing production particulate state ammonium-containing compound of background technology mainly contains two classes, one class is to finish earlier chemical reaction in solution, obtain products with means such as crystallization, spray granulating and dehydration, drying again, contain ammonification fertilizer and azophoska combination fertilizer as various granular or single nutrients of powdery; Another kind of is the slip of pre-ammonification to be sprayed onto with liquefied ammonia in the bed of material of rotation to carry out aminating reaction in the rotating cylinder kind equipment, reaction product is through super-dry, fragmentation, screening, partly become product, another partly for returning charge, produces the technology of granular diammonium phosphate as pre-neutralization-rotary drum secondary ammoniation.The subject matter that exists is ammonification slip thermodynamic property and rheological property, makes it process the difficulty that slip can run into the big and mobile difference of slip of vapor phase ammonia escaped quantity under high temperature, high density.The method of direct injection liquefied ammonia also can produce the problem of being brought by the reaction medium bad dispersibility.

Summary of the invention the present invention discloses the crystals dried integrated approach of a kind of acid goods fluid bed aminating reaction, purpose is to make gas ammonia and reaction medium uniform distribution in the fluidized-bed of particle moisture content 1～12% (wt%), the crystallization that reacts on the particulate materials surface is from heated drying.Gas-liquid-solid phase reaction, crystallization, drying and heat and mass transfer process are finished synchronously, do not need the particle returning charge, and product granularity is even, and is non-caked.All under the condition within the safety limit, make homodisperse granule materials aminating reaction can reach 0.4kg (NH in the concentration of any position of total system ammonia ₃) m ^-3S ^-1Volume intensity.Adopt the inventive method can be from multiple acid material production particulate state ammonium-containing compound, as: from monoammonium phosphate production diammonium phosphate, produce ammonium phosphate calcium, produce potassium-ammonium phosphate from potassium hydrogen phosphate from coarse whiting.

Mainly invention thought of the present invention is to make full use of to disperse that particulate materials system specific surface area is big, reactive behavior is high and the finely dispersed character of medium, gas-liquid-solid phase reaction, crystallization, exsiccant chemistry and physical process are integrated, disposablely on dispersive particulate materials surface finish whole courses of processing.

The technology of the present invention main points are to be one of fluidizing medium with the gas ammonia, according to control requirement to the particle moisture content, above or below distribuor of fluidized bed, introduce reactant gas and moisture, in acid particulate materials surface homodisperse, disposable aminating reaction, crystallization, the exsiccant method finished.The particle moisture content is evenly adjustable in the scope of 1～12% (wt%), and all under the condition within the safety limit, aminating reaction can reach 0.4kg (NH in the concentration of any position of total system ammonia ₃) m ^-3S ^-1Volume intensity.The mode of fluidizing medium introducing and pressure distribution makes the pressure of distribuor of fluidized bed below all can keep appropriateness collision between abundant fluidisation of bed and the particle in the scope of 0.095～0.135MPa.

Compared with prior art, flow process shortens, and facility compact, production intensity is big, power consumption is little, the tail gas amount is few and concentrated.

Description of drawings Fig. 1 is the process flow sheet of the crystals dried integrated approach of acid goods fluid bed aminating reaction provided by the present invention.Among the figure: 1 one fluidized-beds; 2 one air source systems; 3 one source vapor systems; 4 one ammonia origin systems.

Embodiment is set forth embodiment below in conjunction with embodiment

Embodiment 1: from containing p-NH ₃Slip produce phosphorus-ammonium compound fertilizer

Per hour 26 tons 120～125 ℃, the P-NH of moisture 25～30%, N/P molecular ratio 0.9～1.4 ₃Slip is dispersed into the top adding of droplet from fluidized-bed 1.Air source system 2 per hour provides 120, the warm air that 000 standard cubic meter is 140 ℃, mix the laggard grid distributor below of going into fluidized-bed 1 with normal temperature ammonia (volume ratio is less than 6%) that ammonia origin system 4 provides, make acid particles fluidisation ammonification in the bed by grid distributor.Air source system 2 provides another thigh per hour 5,000 standard cubic meter normal temperature air, mix the back with the small amount of ammonia gas (volume ratio is less than 2～3%) that ammonia origin system 4 provides and above the grid distributor of fluidized-bed 1, enter, participate in bed hybrid reaction and abundant heat and mass.Directly obtain per hour 20 tons of the phosphorus-ammonium compound fertilizer particulate product of N/P molecular ratio 1.6～2.2 from fluidized-bed, particle temperature is lower than 68 ℃.Gas continues and acid droplet surface contact reacts heat release transpiring moisture at the particle layers upper space, and temperature drops to below 60 ℃ and is discharged into tail gas clean-up.

Embodiment 2: produce ammonium phosphate calcium from granular coarse whiting

The granular coarse whiting of normal temperature, median size 2～3mm contains P ₂O ₅40～50% (comprising small-amount free phosphoric acid), moisture 2～3%, per hour 20 tons of tops from fluidized-bed 1 add.Air source system 2 provides per hour 60,000 standard cubic meter normal temperature airs, and normal temperature ammonia (volume ratio is less than 6%) the mixing back that provides by ammonia origin system 4 enters bed below the grid distributor of fluidized-bed 1.Air source system 2 provides another thigh 5,000 standard cubic meter normal temperature airs per hour, and temperature is brought up to 80 ℃ of grid distributor tops from fluidized-bed 1 and entered after the conditioning vapor mixing that provides with source vapor system 3, promotes bed to mix and reaction.Per hour directly obtain 22 tons and contain P ₂O ₅35～45%, the granular ammonium phosphate calcium product that contains N 8%, no free phosphoric acid.Particle temperature is lower than 65 ℃.Tail gas is discharged into purification below 60 ℃.

Claims

1. acid goods fluid bed aminating reaction crystallizing and drying, the integrated approach of production particulate state ammonium-containing compound, it is characterized in that after the normal temperature ammonia is with the air that is mixed in normal temperature or 140 ℃ less than 6% volume ratio as fluidizing medium, in the pressure range of 0.095～0.135MPa, enter below the distribuor of fluidized bed, make the acid particles bed fluidisation ammonification of particle moisture content 1～12% (wt%) by grid distributor, reactive crystallization, from heated drying, one step was finished reaction-granulation-exsiccant combination operation, directly obtained granular phosphorus ammonium or ammonium phosphate calcium product that temperature is lower than 68 ℃.

2. the integrated approach of acid goods fluid bed aminating reaction crystallizing and drying according to claim 1, production particulate state ammonium-containing compound is characterized in that the P-NH of 120～125 ℃ of temperature, moisture 25～30%, N/P molecular ratio 0.9～1.4 ₃The slip droplet adds from the fluidized-bed top, the normal temperature ammonia adds from the distribuor of fluidized bed below as fluidizing medium with the air that is mixed in 140 ℃ less than 6% volume ratio, another strand normal temperature air mixes the back and adds, promotes bed hybrid reaction and heat and mass from the distribuor of fluidized bed top with the small amount of ammonia gas of volume ratio 2～3%, make aminating reaction volume intensity reach 0.4kg (NH ₃) m ^-3S ^-1, directly obtaining the phosphorus ammonium particulate product of N/P molecular ratio 1.6～2.2 from fluidized-bed, particle temperature is lower than 68 ℃, and gas continues at particle layers upper space and P-NH ₃Slip droplet surface contact reacts heat release transpiring moisture, temperature drop to below 60 ℃ and send tail gas clean-up.

3. the integrated approach of acid goods fluid bed aminating reaction crystallizing and drying according to claim 1, production particulate state ammonium-containing compound is characterized in that containing P ₂O ₅40～50%, the granular coarse whiting particle of normal temperature of moisture 2～3%, median size 2～3mm adds from the top of fluidized-bed, containing the ammonia volume ratio adds from the distribuor of fluidized bed below as fluidizing medium less than 6% normal temperature air, temperature is brought up to 80 ℃, is added from the top of distribuor of fluidized bed after another strand normal temperature air and the conditioning vapor mixing, promote bed hybrid reaction and heat and mass, make aminating reaction volume intensity reach 0.4kg (NH ₃) m ^-3S ^-1, directly obtain containing P ₂O ₅35～45%, contain the granular ammonium phosphate calcium product of N8%, no free phosphoric acid, particle temperature is lower than 65 ℃, and tail gas send tail gas clean-up below 60 ℃.