CN112946060A - Specific susceptibility method for measuring slagging performance of bituminous coal ash - Google Patents

Abstract

The invention discloses a specific susceptibility method for measuring the caking property of bituminous coal ash, which comprises the following steps: 1. making a test coal ash sample, and recording the weight Mh of the coal ash sample; using a stamper of organic glass, the weight M of the stamper is first weighed₀Pressing the coal ash sample until the pressing die is full, avoiding knocking the pressing die during the sample loading process, and weighing the coal ash sample and the pressing die by using a balance₁，Mh＝M₁‑M₀(ii) a 2. Measuring the magnetic susceptibility K value of the coal ash sample; inserting the coal ash sample subjected to die pressing into one end of a magnetizer coil, and reading a magnetic susceptibility K value; 3. calculating specific susceptibility X, wherein X is K/Mh; 4. judging the slagging performance of the coal sample according to the specific susceptibility X, wherein the higher the specific susceptibility X value is, the more serious the slagging performance is, and obtaining the grading range of the slagging trend of the specific susceptibility X value of the bituminous coal according to the corresponding relation of the specific susceptibility X and the slagging index Sc of the one-dimensional flame furnace; the method of the invention needs few samples, and the test method is simple and easy to test. For severe diseaseThe difference of the types of the slagging coals can be displayed more accurately.

Description

Specific susceptibility method for measuring slagging performance of bituminous coal ash

Technical Field

The invention relates to the technical field of judgment of slagging performance of coal for power, in particular to a specific susceptibility method for measuring slagging performance of bituminous coal ash, which is suitable for bituminous coal.

Background

The coal ash slagging performance is an important index influencing the design and operation of a boiler, a simple index capable of accurately judging the slagging performance of a coal sample does not exist at present, different indexes have different limitations, and the more accurate coal ash slagging performance needs to be determined through a combustion test furnace, but the test method is complex.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a specific susceptibility method for measuring the caking property of the bituminous coal ash, which is suitable for bituminous coal; the invention has the advantages of few samples required by the test and simple and easy test method.

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

a specific susceptibility method for measuring the caking property of bituminous coal ash comprises the following steps:

the first step is as follows: making a test coal ash sample, and recording the weight Mh, g of the coal ash sample;

using a stamper of organic glass, the weight M of the stamper is first weighed₀In units of g; pressing the coal ash sample until the pressing die is full, avoiding knocking the pressing die during sample loading, and weighing the coal ash sample and the pressing die by using a balance₁In units of g;

Mh＝M₁-M₀

the second step is that: measuring the magnetic susceptibility K value of the coal ash sample;

inserting the coal ash sample subjected to die pressing into one end of a magnetizer coil, and reading a magnetic susceptibility K value;

the third step: calculating specific susceptibility X, wherein the specific susceptibility X represents magnetic moment generated by 1 gram of object under the action of an external magnetic field with the magnetic field intensity of 1 oersted, and the unit is cm³/g；

X＝K/Mh

The fourth step: judging the slag bonding performance of the coal sample according to the specific susceptibility X

The higher the specific susceptibility X value is, the more serious the slagging performance is, and the grading range of the slagging tendency of the specific susceptibility X value of the bituminous coal is obtained by the corresponding relation between the specific susceptibility X and the slagging index Sc of the one-dimensional flame furnace, which is shown in the following table:

X×10-6	tendency to slag
		＜75	Is low in
75～150	In
		150～290	Height of
＞290	Severe severity of disease

Compared with the prior art, the invention has the following advantages:

the specific susceptibility method for measuring the slagging performance of the bituminous coal ash is suitable for bituminous coal. The invention has the advantages of few samples required by the test and simple and easy test method. For the coal types with serious slag bonding, the difference can be displayed more accurately. And the test result has stronger correlation with the one-dimensional flame furnace slagging index with wide industrial application, which shows that the index also has industrial application value.

Detailed Description

The test principle is as follows: a magnetic susceptibility measuring instrument is prepared, and the change of magnetic flux is converted into an electric signal k to be directly read when the magnetic susceptibility is measured.

The instrument probe mainly comprises a primary coil and a secondary coil. The primary coil is a magnetizing coil and generates a magnetic field; the secondary coil is then used for the determination of the change in magnetic flux. The secondary coil is an upper reverse series coil and a lower reverse series coil. In the absence of a sample, the signals cancel each other out. When the magnetic sample is inserted into one end, one of the upper and lower coils is far away from the sample, and the influence of the sample on the magnetic flux of the coil is very little and can be ignored; while the other coil, the plug-in coil, generates additional magnetic flux. The electrical signal across the secondary coil then shows the change in magnetic flux. The change in the magnetic flux at the sample end, Δ φ, can be expressed as follows.

Δφ＝NμHS-NHS＝NHS(μ-1)

Where Δ φ — magnetic flux variation, wb;

h — the magnetic field strength generated by the primary coil, oersted (H);

n is the number of turns of the secondary coil at the sample end;

s-effective area of the secondary coil, m²；

μ -the magnetic permeability of the sample, oersted/m (H/m);

relationship between magnetic permeability μ and magnetic susceptibility K:

μ＝1+4πK

then, the above equation becomes:

Δφ＝4πKNHS

in this formula, N, S, H is a constant of the instrument, and pi is a constant, and pi is 3.14159. Then

Proportional to the magnetic susceptibility K of the sample this timeInstrument constant 4 pi NHS ═ 1 × 10^-6I.e., K ═ Δ Φ.

The first step is as follows: making a test coal ash sample, and recording the weight Mh, g of the coal ash sample;

using a stamper of organic glass, the weight M of the stamper is first weighed₀In units of g; pressing the coal ash sample until the pressing die is full, avoiding knocking the pressing die during sample loading, and weighing the coal ash sample and the pressing die by using a balance₁In units of g;

Mh＝M₁-M₀

the second step is that: measuring the magnetic susceptibility K value of the coal ash sample;

inserting the coal ash sample subjected to die pressing into one end of a magnetizer coil, and reading a magnetic susceptibility K value;

the third step: calculating specific susceptibility X, wherein the specific susceptibility X represents magnetic moment generated by 1 gram of object under the action of an external magnetic field with the magnetic field intensity of 1 oersted, and the unit is cm³/g；

X＝K/Mh

The fourth step: judging the slag bonding performance of the coal sample according to the specific susceptibility X

The higher the specific susceptibility X value is, the more serious the slagging performance is, and the grading range of the slagging tendency of the specific susceptibility X value of the bituminous coal is obtained by the corresponding relation between the specific susceptibility X and the slagging index Sc of the one-dimensional flame furnace, which is shown in the following table:

X×10-6	tendency to slag
		＜75	Is low in
75～150	In
		150～290	Height of
＞290	Severe severity of disease

。

Specific embodiment example 1: magnetic susceptibility testing of Shenhua coal ash

The first step is as follows: making a test coal ash sample, and recording the weight Mh, g of the coal ash sample;

the volume of use is 0.63585cm³Pressing a mold of an organic glass, weighing the weight M of the mold₀In units of g; pressing the coal ash sample until the pressing die is filled, avoiding knocking the pressing die in the sample loading process, and weighing the coal ash sample and the pressing die by using a balance, wherein the weight of the coal ash sample and the pressing die is M1, and the unit is g;

this test weighs M₀＝2.0160g，M₁＝2.5901g；

Mh＝M1-M₀＝2.5901-2.0160＝0.5741g；

The second step is that: measuring the magnetic susceptibility K value of the coal ash sample;

and inserting the coal ash sample subjected to die pressing into one end of a magnetizer coil, and reading a magnetic susceptibility K value.

The magnetic susceptibility K of the ash sample is 182 multiplied by 10^-6

The third step: calculating specific susceptibility X;

X＝K/Mh＝182×10^-6/0.5741＝317×10^-6(cm³/g)

the fourth step: judging the slag bonding performance of the coal sample according to the specific susceptibility X

The higher the X value, the more severe the slagging performance. The classification range of the slagging tendency of the specific susceptibility X value of the general bituminous coal is obtained by the corresponding relation of the specific susceptibility X and the slagging index Sc of the one-dimensional flame furnace, and the classification range is shown in the following table.

X×10-6	Tendency to slag
		＜75	Is low in
75～150	In
		150～290	Height of
＞290	Severe severity of disease

The X of the coal sample in the test is 317 multiplied by 10^-6(m³/g)，>290×10^-6Therefore, the type of the severely slagging coal is judged. The slag-bonding index Sc of the one-dimensional flame furnace is 1.135, and the coal is also judged to be seriously slag-bonded coal, which shows the accuracy of the testing method of the invention.

Claims (1)

1. A specific susceptibility method for measuring the slagging performance of bituminous coal ash is characterized in that: the method comprises the following steps:

the first step is as follows: making a test coal ash sample, and recording the weight Mh, g of the coal ash sample;

using a stamper of organic glass, the weight M of the stamper is first weighed₀In units of g; pressing the coal ash sample until the pressing die is full, avoiding knocking the pressing die during sample loading, and weighing the coal ash sample and the pressing die by using a balance₁In units of g;

Mh＝M₁-M₀

the second step is that: measuring the magnetic susceptibility K value of the coal ash sample;

inserting the coal ash sample subjected to die pressing into one end of a magnetizer coil, and reading a magnetic susceptibility K value;

the third step: calculating specific susceptibility X, wherein the specific susceptibility X represents magnetic moment generated by 1 gram of object under the action of an external magnetic field with the magnetic field intensity of 1 oersted, and the unit is cm³/g；

X＝K/Mh

The fourth step: judging the slag bonding performance of the coal sample according to the specific susceptibility X

The higher the specific susceptibility X value is, the more serious the slagging performance is, and the grading range of the slagging tendency of the specific susceptibility X value of the bituminous coal is obtained by the corresponding relation between the specific susceptibility X and the slagging index Sc of the one-dimensional flame furnace, which is shown in the following table:

X×10^-6 tendency to slag ＜75 Is low in 75～150 In 150～290 Height of ＞290 Severe severity of disease

。