阅读说明：本技术 一种磷酸氢钙生产方法 (Production method of calcium hydrogen phosphate ) 是由 孙天桥 于 2019-03-22 设计创作，主要内容包括：本发明提供一种磷酸氢钙生产方法,其特征在于包括以下几个步骤：将磷矿进行磨浆、萃取、过滤、酸溶、一次脱氟、二次脱氟、澄清、中和、稠浆、固液分离、固相干燥后得到成品,该方法具有生产量大,生产稳定,工艺完善,原料充分利用,采用二次脱氟作业,能将产品中的氟控制在符合生产要求。(The invention provides a production method of calcium hydrophosphate, which is characterized by comprising the following steps: the phosphorite is ground into pulp, extracted, filtered, acid-dissolved, once defluorinated, twice defluorinated, clarified, neutralized, thick pulp, solid-liquid separated and solid phase dried to obtain the product.)

1. The production method of calcium hydrophosphate is characterized by comprising the following steps:

the method comprises the following steps: grinding the phosphate ore into pulp under the condition of circulating water, and homogenizing ore pulp after screening;

step two: adding ore pulp and sulfuric acid into an extraction kettle for extraction and separation to obtain filtrate;

step three: adding phosphate rock powder into the filtrate and simultaneously performing desulfurization operation, and clarifying to obtain a crude acid clear solution;

step four: carrying out acid dissolution on the acetic acid clear solution, adding calcium carbonate for pulping, carrying out primary defluorination treatment, and clarifying;

step five: clarifying the material subjected to primary defluorination, performing secondary defluorination treatment, and adding calcium oxide pulping material during secondary defluorination;

step six: clarifying the secondary defluorinated material, and adding calcium oxide pulping material for neutralization;

step seven: clarifying the neutralized material, and then dehydrating to obtain thick slurry;

step eight: and carrying out solid phase separation on the thick slurry, and drying to obtain a finished product.

2. A process for the production of dibasic calcium phosphate according to claim 1, wherein: and in the first step, the coarse particles obtained by screening are added into a pulping machine for pulping.

3. A process for the production of dibasic calcium phosphate according to claim 1, wherein: and (5) carrying out secondary extraction treatment on the thick slurry obtained in the step two.

4. A process for the production of dibasic calcium phosphate according to claim 1, wherein: and C, carrying out plate-frame filter pressing on the solid obtained by primary defluorination in the fourth step, adding the obtained liquid phase into the clarified liquid, and sending the obtained solid into a fertilizer branch plant.

5. A process for the production of dibasic calcium phosphate according to claim 1, wherein: and sending the liquid phase obtained by solid-liquid separation in the step eight into the step seven for clarification and use.

Technical Field

The invention relates to the technical field of chemistry and metallurgy, in particular to a production method of calcium hydrophosphate.

Background

Calcium hydrogen phosphate is white monoclinic powder, is stable in air, loses crystal water to be anhydrous after being heated to 75 ℃, and can be used as a leavening agent for biscuits and fermented flour products according to the specification.

At present, a wet process and a dry process are generally adopted at home and abroad to produce the calcium hydrophosphate, wherein the wet process is to add a solid raw material into a phosphoric acid solution prepared by the wet process to generate the calcium hydrophosphate dissolved in water, and the calcium hydrophosphate is dried, crushed and screened after being subjected to vacuum concentration, cooling crystallization and precipitation to obtain a calcium hydrophosphate crystal.

Disclosure of Invention

The invention aims to provide a production method of calcium hydrophosphate, which fully utilizes the existing production process of calcium hydrophosphate and meets the requirement of large-scale batch production.

In order to achieve the purpose, the invention adopts the technical scheme that:

the production method of calcium hydrophosphate is characterized by comprising the following steps:

the method comprises the following steps: grinding the phosphate ore into pulp under the condition of circulating water, and homogenizing ore pulp after screening;

step two: adding ore pulp and sulfuric acid into an extraction kettle for extraction and separation to obtain filtrate;

step three: adding phosphate rock powder into the filtrate and simultaneously performing desulfurization operation, and clarifying to obtain a crude acid clear solution;

step four: carrying out acid dissolution on the acetic acid clear solution, adding calcium carbonate for pulping, carrying out primary defluorination treatment, and clarifying;

step five: clarifying the material subjected to primary defluorination, performing secondary defluorination treatment, and adding calcium oxide pulping material during secondary defluorination;

step six: clarifying the secondary defluorinated material, and adding calcium oxide pulping material for neutralization;

step seven: clarifying the neutralized material, and then dehydrating to obtain thick slurry;

step eight: and carrying out solid phase separation on the thick slurry, and drying to obtain a finished product.

As a further improvement of the invention, the coarse particles obtained by screening in the step one are added into a refiner for refining.

As a further improvement of the invention, the thick slurry obtained in the second step is subjected to a re-extraction treatment.

As a further improvement of the invention, after plate-and-frame filter pressing is carried out on the solid obtained by primary defluorination in the fourth step, the obtained liquid phase is added with the clarified liquid, and the obtained solid is sent to a fertilizer branch plant.

As a further improvement of the invention, the liquid phase obtained by solid-liquid separation in the step eight is sent to the step seven for clarification.

The method has the advantages that the method is reasonable and suitable for large-scale production, has large production capacity, stable production, perfect process and full utilization of raw materials, and can control the fluorine in the product to meet the production requirements by adopting secondary defluorination operation.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Detailed Description

The invention is further illustrated with reference to fig. 1.

The production method of calcium hydrophosphate is characterized by comprising the following steps:

the method comprises the following steps: grinding the phosphate ore into pulp under the condition of circulating water, and homogenizing ore pulp after screening;

step two: adding ore pulp and sulfuric acid into an extraction kettle for extraction and separation to obtain filtrate;

step three: adding phosphate rock powder into the filtrate and simultaneously performing desulfurization operation, and clarifying to obtain a crude acid clear solution;

step four: carrying out acid dissolution on the acetic acid clear solution, adding calcium carbonate for pulping, carrying out primary defluorination treatment, and clarifying;

step five: clarifying the material subjected to primary defluorination, performing secondary defluorination treatment, and adding calcium oxide pulping material during secondary defluorination;

step six: clarifying the secondary defluorinated material, and adding calcium oxide pulping material for neutralization;

step seven: clarifying the neutralized material, and then dehydrating to obtain thick slurry;

step eight: and carrying out solid phase separation on the thick slurry, and drying to obtain a finished product.

As a further preferable mode of the present invention, in the step one, the coarse particles obtained by screening are added into a refiner for refining.

As a further preferable embodiment of the present invention, the thick slurry obtained in the second step is subjected to a re-extraction treatment.

As a further preferable scheme of the invention, after the solid obtained by the primary defluorination in the fourth step is subjected to plate-and-frame filter pressing, the obtained liquid phase is added with the clarified liquid, and the obtained solid is sent to a fertilizer branch plant.

In a further preferred embodiment of the present invention, the liquid phase obtained by the solid-liquid separation in the step eight is sent to a step seven for clarification.

The method has the advantages that the reasonable production method of the calcium hydrophosphate suitable for large-scale production is developed through the design of the whole process flow, the method has the advantages of large production capacity, stable production, perfect process and full utilization of raw materials, and the fluorine in the product can be controlled to be in accordance with the production requirement by adopting secondary defluorination operation.