Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for detecting content of carbonate in desulfurized gypsum

A technology for desulfurization gypsum and a detection method, which is applied to measurement devices, instruments, chemical analysis by combustion, etc., can solve the problems of experimental errors, complicated operations, consumption of alkali, etc. Effect

Pending Publication Date: 2022-05-17
SHANDONG WEIZHEN TEST & ANALYSIS +1
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] 1. Excessive hydrochloric acid is added in the back titration method. Hydrochloric acid can react with other alkaline components in gypsum (including traces of basic oxides such as magnesium oxide), resulting in a large consumption of hydrochloric acid and affecting the accuracy of the results.
[0008] 2. Since desulfurization gypsum may contain sulfite, sulfur dioxide gas will be produced after encountering acid, which will also be absorbed by alkali and consume alkali, resulting in high measurement results
[0009] 3. The operation process of the above method is complicated and cumbersome, and requires a high level of technical skills of the operators, so it is not suitable for accurate detection of carbonate content
[0010] 4. Since the desulfurized gypsum contains some organic matter, the conventional TOC measurement method will lead to high measurement results, resulting in experimental errors and affecting the accuracy of the results
[0011] From a comprehensive analysis, both of the above two schemes involve titration operations, which leads to certain errors in the experimental results depending on the proficiency of the operator, the purity of the reagents, and the test environment.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for detecting content of carbonate in desulfurized gypsum
  • Method for detecting content of carbonate in desulfurized gypsum
  • Method for detecting content of carbonate in desulfurized gypsum

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0052] 1) Weigh 5.0g of desulfurized gypsum sample (grind as much as possible), add it to a flat-bottomed flask, add 20ml of ultrapure water to infiltrate it, and slowly drop 50mL of dilute sulfuric acid (mass concentration: 10%) into the flat-bottomed flask with a separatory funnel (This process is continuously heated and stirred at 45°C), and the gas generated by the reaction is passed into an excessive amount of sodium hydroxide solution (concentration: 0.15mol / L) under airtight conditions until no bubbles are generated in the sodium hydroxide solution. , to obtain the solution to be analyzed containing soluble carbonate.

[0053] 2) Use a TOC analyzer (catalytic combustion oxidation-non-dispersive infrared detection) to detect the content of inorganic carbon in the liquid to be analyzed at 150°C, and calculate the content of carbonate in desulfurized gypsum according to the formula (1). The desulfurized gypsum samples were tested three times (A1, A2, A3), and the results a...

Embodiment 2

[0060] 1) Weigh 5.0g of desulfurized gypsum sample (grind as much as possible), add it to a flat-bottomed flask, add 20mL of ultrapure water to infiltrate it, and slowly drop 50mL of dilute nitric acid (mass concentration: 10%) into the flat-bottomed flask with a separatory funnel (This process is continuously heated and stirred at 45° C.), and the gas generated by the reaction is passed into an excessive amount of sodium hydroxide solution (concentration 0.15mol / L) under airtight conditions until no bubbles are produced in the sodium hydroxide solution, to obtain The solution to be analyzed contains soluble carbonates.

[0061] 2) Use a TOC analyzer (catalytic combustion oxidation-non-dispersive infrared detection) to detect the content of inorganic carbon in the liquid to be analyzed at 260°C, and calculate the content of carbonate in desulfurized gypsum according to formula (1). The desulfurized gypsum samples were tested three times (A1, A2, A3), and the results are shown ...

Embodiment 3

[0069] This embodiment adopts desulfurized gypsum A (known calcium carbonate content is 30%) and desulfurized gypsum A+1, A+2 (the calcium carbonate content after the added standard is 52.1% respectively) of the unmarked calcium carbonate standard sample. , 55.3%) to carry out the recovery rate experiment according to the method of embodiment 1, the result is as follows table 3.

[0070] Table 3 Recovery experimental results

[0071] sample Original calcium carbonate content% test value / % Recovery rate / % A 30 - - A+1 52.1 52.6 100.9 A+2 55.3 55.1 99.6

[0072] Results The recoveries of calcium carbonate tested after twice adding the standard were 100.9% and 99.6% respectively, indicating that the accuracy of the method of the present invention is good and the test results are reliable.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
recovery rateaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for detecting the content of carbonate in flue gas desulfurization gypsum. The method comprises the following steps: (1) mixing the flue gas desulfurization gypsum with an acid solution, and carrying out a first reaction to obtain a gas product containing carbon dioxide; (2) introducing the obtained gas product containing carbon dioxide into excessive alkali liquor under a closed condition, and carrying out a second reaction until no bubbles are generated in the alkali liquor, so as to obtain a solution containing soluble carbonate; (3) detecting the content of inorganic carbon in the solution containing the soluble carbonate by using a TOC (Total Organic Carbon) analyzer; and (4) calculating the content of the carbonate in the desulfurized gypsum according to the obtained content of the inorganic carbon. The method reduces artificial accidental errors, improves the accuracy of a detection result, and is less in time consumption and high in detection efficiency.

Description

technical field [0001] The invention belongs to the technical field of carbonate detection, and in particular relates to a method for detecting carbonate content in desulfurized gypsum. Background technique [0002] In the limestone-gypsum flue gas desulfurization system, it is necessary to know the carbonate content in the desulfurization gypsum in time to adjust the amount of limestone added and the operating parameters of the system. The desulfurized gypsum produced in the desulfurization system is used as solid waste in accordance with national environmental protection requirements for comprehensive utilization of waste. Desulfurized gypsum can be used as a substitute for natural gypsum, used as building gypsum (production of plasterboard and gypsum blocks) and cement coagulant . When used as building gypsum, the insoluble impurity carbonate in desulfurized gypsum will produce CaO and MgO after calcination, which will increase the alkalinity of gypsum and lead to the pr...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01N31/12G01N31/10G01N21/17
CPCG01N31/12G01N31/10G01N21/17
Inventor 张静静杨桂芹孙庆龙焦金玲孙光玲余宏涛
Owner SHANDONG WEIZHEN TEST & ANALYSIS