CN1285511A - Quick calcium content measuring method for ground raw material of non-outkiln decomposed cement kiln batch - Google Patents

Abstract

In invented detection method, cane sugar and calcium oxide react to produce calcium sucrate, and the calcium sucrate is titrated by hydrochloric acid solution to measure out calcium oxide content, then the sample whose calcium oxide content is tested is titrated by sodium hydroxide solution to measure out calcium carbonate content, then the calcium carbonate content is converted into calcium oxide content, so that said calcium oxide content and the above-mentioned measured calcium oxide content are added together so as to obtain the calcium content being in raw material of cement. Said invention is quick in detection speed, accurate in detection result, low in cost and good in effect, etc.

Description

Method for rapidly detecting calcium content of milled raw material of non-kiln-exterior decomposed cement kiln burdening

The invention relates to a rapid detection method for calcium content in cement raw materials, in particular to a rapid detection method for calcium content in milled raw materials of non-kiln outside decomposed cement kiln ingredients.

At present, two methods for firing cement exist in China: one is an advanced kiln decomposition process using cement raw materials; one is the conventional process of directly firing cement raw materials without decomposing the raw materials outside the kiln. The former has the advantages of pre-decomposing cement raw material by using waste heat, saving coal consumption, improving quality and yield, but has the disadvantages of large investment and unsuitable process technology for the productionline of the middle and small vertical kilns which are the majority of China. As early as the fifth and sixty years, cement experts in China propose that lime is used for replacing limestone (the principle of decomposition outside a kiln is the same as that of the lime) to fire cement, the lime is used for replacing the limestone, so that the crushing difficulty of raw materials can be reduced, the quality and the yield are improved, the electricity consumption, the material consumption and the coal consumption are saved, the effect of a decomposition process outside the kiln can be achieved without adding equipment, but the detection method for detecting the calcium content of ground raw materials by using new raw materials prepared by lime for replacing the limestone is not ideal, and the production cannot be controlled in time, so the assumption is not successful in actual production.

The invention aims to provide a method for quickly detecting calcium content of ground raw materials of non-kiln-exterior decomposed cement kiln ingredients, which can quickly and simply detect the calcium content of the raw materials.

The technical scheme of the invention is as follows: a method for rapidly detecting calcium content of milled raw materials of non-kiln exterior decomposed cement kiln ingredients comprises the following steps: 1. reacting sucrose with calcium oxide to generate calcium sucrose, and titrating the calcium sucrose with hydrochloric acid solution to measure the content of calcium oxide; 2. titrating the sample after testing the calcium oxide by using a sodium hydroxide solution to measure the content of the calcium carbonate; 3. and (4) converting the calcium carbonate content measured in the step (2) into calcium oxide, and adding the calcium oxide content measured in the step (1) to obtain the calcium content in the raw material. The specific steps for testing the calcium oxide are as follows: (1) taking part of the raw material out of the milled raw material for batching as a sample, and placing the sample into a bottle; (2) adding sucrose into a bottle filled with a sample; (3) putting a magnetic stirring rod into a bottle filled with a sample and cane sugar; (4) adding distilled water into the bottle, and plugging the bottle mouth; (5) placing the bottle on an electromagnetic stirrer to stir for 10 minutes; (6) opening the bottle stopper, and washing the bottle wall and the bottle stopper with water; (7) dripping 2-3 drops of 1% phenolphthalein indicator solution into the bottle; (8) titrating with 0.5N hydrochloric acid solution until the pink color of the solution disappears and does not reappear within 30 seconds; the percentage of calcium oxide is calculated as follows: $\mathrm{Cao}=\frac{\mathrm{NV}\×0.02804}{G}\×100$

in the formula: the equivalent concentration of the N-hydrochloric acid standard solution,

v-time the volume of the titrated hydrochloric acid standard solution is consumed,

g-the weight of the sample,

0.02804-grams per gram equivalent of calcium oxide. The specific steps for testing calcium carbonate are as follows: (1) adding 20ml of 0.5mol/L hydrochloric acid into the solution after titration of calcium oxide; (2) washing the bottle wall with a small amount of water, heating to boil, and shaking the bottle several times during heating; taking down the bottle and cooling, and washing the bottle mouth and the bottle wall with a small amount of water; 5-6 drops ofphenolphthalein indicator solution with the concentration of 10g/L are added into a bottle; titrating to reddish with 0.2500mol/L sodium hydroxide standard solution until the solution disappears within 30 seconds; the titration value of calcium carbonate is calculated as follows: ${\mathrm{CaCO}}_3=\frac{(C_1{V}_1-C_2{V}_2)\×50.0}{m}\×100$

in the formula: c₁Equivalent concentration mol/L of hydrochloric acid standard solution

V₁Consumption of volume of titrated hydrochloric acid standard solution in ml

G₂Concentration mol/L of sodium hydroxide Standard titration solution

V₂Volume ml of sodium hydroxide standard titration solution consumed for titration

50.0-(1/2CaCO₃) Molar mass g/mol of

m-the weight g of the sample converts the tested calcium carbonate into calcium oxide, and then the calcium oxide is added with the tested calcium oxide to obtain the calcium content in the raw material, wherein the calculation formula is as follows: 。

the method for quickly detecting the calcium content of the milled raw material of the non-kiln outside decomposed cement kiln ingredients has the advantages of quick and accurate detection of the calcium content of the milled raw material of the cement ingredients, low cost, large effect, wide practicability, feasible reconstruction of a small kiln and huge economic and social benefits.

A method for rapidly detecting calcium content of milled raw materials of non-kiln exterior decomposed cement kiln ingredients comprises the following specific steps: 1. testing of calcium oxide: taking part of the raw material from the milled raw material obtained by mixing the ingredients as a sample, putting the sample into a conical flask, adding cane sugar into the conical flask filled with the sample, covering the surface of the sample with the cane sugar to reduce the contact between the sample and air, putting a magnetic stirring rod into the conical flask filled with the sample and the cane sugar, adding 40-50ml of distilled water into the conical flask, immediately plugging the bottle mouth, putting the conical flask on an electromagnetic stirrer for stirring for 10 minutes, and reacting calcium oxide with the cane sugar to generate calcium sucrose, wherein the reaction formula is as follows: (ii) a Opening the bottle stopper, washing the bottle wall and the bottle stopper with water, dripping 2-3 drops of 1% phenolphthalein indicator solution into the bottle, titrating with 0.5N hydrochloric acid solution until pink of the solution disappears and does not reappear within 30 seconds, wherein the reaction formula is as follows: c₁₂H₂₂O₁₁·Cao·2H₂O+CaCl₂+3H₂O, the percentage of calcium oxide is calculated according to the following formula: $\mathrm{Cao}=\frac{\mathrm{NV}\×0.02804}{G}\×100$

in the formula: the equivalent concentration of the N-hydrochloric acid standard solution,

v-time the volume of the titrated hydrochloric acid standard solution is consumed,

g-sample weight, 0.02804-grams per gram equivalent of calcium oxide.

2. Testing of calcium carbonate: adding 20ml of 0.5mol/L hydrochloric acid into the solution after titration of calcium oxide; (2) washing the bottle wall with a small amount of water, then placing the bottle on an electric furnace to be heated to boil, shaking the bottle for several times in the heating process to promote the complete decomposition of the sample, taking off the bottle to cool, washing the bottle mouth and the bottle wall with a small amount of water, adding 5-6 drops of 10g/L phenolphthalein indicator solution into the bottle, titrating the solution to reddish with 0.2500mol/L sodium hydroxide standard solution, and losing within 30 seconds, wherein the reaction formula of the titration time is as follows: the titration value of calcium carbonate is calculated as follows: ${\mathrm{CaCO}}_3=\frac{(C_1{V}_1-C_2{V}_2)\×50.0}{m}\×100$

in the formula: c₁Equivalent concentration of hydrochloric acid standard solution, mol/L

V₁Consumption of volume of titrated hydrochloric acid standard solution in ml

G₂Concentration mol/L of sodium hydroxide Standard titration solution

V₂Volume ml of sodium hydroxide standard titration solution consumed for titration

50.0-(1/2CaCO₃) Molar mass of (2), g/mol

m-the weight g3 of the sample, converting the tested calcium carbonate into calcium oxide, adding the calcium oxide to the tested calcium oxide to obtain the calcium content in the raw material, wherein the calculation formula is as follows: 。

Claims (4)

1. a method for rapidly detecting calcium content of milled raw materials of non-kiln exterior decomposed cement kiln ingredients comprises the following steps: 1. reacting sucrose with calcium oxide to generate calcium sucrose, and titrating the calcium sucrose with hydrochloric acid solution to measure the content of calcium oxide; 2. titrating the sample after testing the calcium oxide by using a sodium hydroxide solution to measure the content of the calcium carbonate; 3. and (4) converting the calcium carbonate content measured in the step (2) into calcium oxide, and adding the calcium oxide content measuredin the step (1) to obtain the calcium content in the raw material.

2. The rapid calcium content detection method for milled raw materials of non-kiln decomposition cement kiln ingredients according to claim 1, which is characterized in that: the specific steps for testing the calcium oxide are as follows:

(1) taking part of the raw material out of the milled raw material for batching as a sample, and placing the sample into a bottle;

(2) adding sucrose into a bottle filled with a sample;

(3) a magnetic stirring rod is put into a bottle filled with a sample and cane sugar,

(4) adding distilled water into the bottle, and plugging the bottle mouth;

(5) placing the bottle on an electromagnetic stirrer to stir for 10 minutes;

(6) opening the bottle stopper, and washing the bottle wall and the bottle stopper with water;

(7) dripping 2-3 drops of 1% phenolphthalein indicator solution into the bottle;

(8) titrating with 0.5N hydrochloric acid solution until the pink color of the solution disappears and does not reappear within 30 seconds;

the percentage of calcium oxide is calculated as follows: $\mathrm{Cao}=\frac{\mathrm{NV}\×0.02804}{G}\×100$ in the formula: the equivalent concentration of the N-hydrochloric acid standard solution,

v-time the volume of the titrated hydrochloric acid standard solution is consumed,

g-the weight of the sample,

0.02804-grams per gram equivalent of calcium oxide.

3. The rapid calcium content detection method for milled raw materials of non-kiln decomposition cement kiln ingredients according to claim 1, which is characterized in that: the specific steps for testing calcium carbonate are as follows:

(1) adding 20ml of 0.5mol/L hydrochloric acid into the solution after titration of calcium oxide;

(2) washing the bottle wall with a small amount of water, heating to boil, and shaking the bottle several times during heating;

(3) taking down the bottle and cooling, and washing the bottle mouth and the bottle wall with a small amount of water;

(4) 5-6 drops of phenolphthalein indicator solution with the concentration of 10g/L are added into a bottle;

(5) titrating to reddish with 0.2500mol/L sodium hydroxide standard solution until the solution disappears within 30 seconds;

the titration value of calcium carbonate is calculated as follows: ${\mathrm{CaCO}}_3=\frac{(C_1{V}_1-C_2{V}_2)\×50.0}{m}\×100$

in the formula: c₁Equivalent concentration of hydrochloric acid standard solution, mol/L

V₁Consumption of volume of titrated hydrochloric acid standard solution in ml

G₂Concentration mol/L of sodium hydroxide Standard titration solution

V₂Volume m of sodium hydroxide standard titration solution consumed in the titration

50.0-(1/2CaCO₃) Molar mass of (2), g/mol

m-weight g of sample

4. The rapid calcium content detection method for milled raw materials of non-kiln decomposition cement kiln ingredients according to claim 1, which is characterized in that: converting the tested calcium carbonate into calcium oxide, and adding the calcium oxide to the tested calcium oxide to obtain the calcium content in the raw material, wherein the calculation formula is as follows: 。