1. Field of the Invention
The present invention relates to a method, and more particularly to a method for measuring an outline of a stratum of a reactant and a path of charging the reactant in a blast furnace.
2. Description of Related Art
A Blast furnace is a huge chemical reaction device. The blast furnace has multiple reactants. The reactants are layered in stratum, comprise coke and iron ore and proceeds oxidation-reduction reaction to reduce the iron oxides into pig iron. Additionally, gas as carbon monoxide is generated in the blast furnace when proceeding the oxidation-reduction reaction. Distribution of the gas influences the efficiency of the oxidation-reduction reaction. Furthermore, the gas distribution is related to the outline of the top reactant stratum in the blast furnace and paths of charging the reactants.
Two methods are used to measure the outline of the top reactant stratum in the blast furnace today. One method is called indirect measuring method. The indirect measuring method comprises steps of determining the paths of charging the reactants and measuring an outline of the top reactant stratum in the blast furnace. An equation of the paths of charging the reactants is obtained after proceeding the step of determining the paths of charging the reactants. The step of measuring an outline of the top reactant stratum in the blast furnace comprises integrating the equation of the paths of charging the reactants.
Another method is called direct measuring method. The direct measuring method is performed by a microwave distance measuring device to determine the outline of the top reactant stratum in the blast furnace after finishing charging the reactants.
However, measuring the outline of the top reactant stratum in the blast furnace and determining the paths of reactants when charging the reactants are difficult because the temperature and the pressure inside the blast furnace are extremely high. The methods described cannot provide accurate results.
To overcome the shortcomings, the present invention provides a method for measuring an outline of a stratum of a reactant and a path of charging the reactant in a blast furnace to mitigate or obviate the aforementioned problems.
The main objective of the invention is to provide a method for measuring the outline of a reactant layer in a blast furnace and the path of charging the reactant.
A method in accordance with the present invention comprises steps of providing a three-dimensional (3-D) laser scanner, providing a computer, obtaining point group data (PGD) and calculating an outline of a top reactant stratum from the PGD. The step of providing a 3-D laser scanner directs a 3-D laser scanner at reactant strata in a blast furnace and outputs PGD that represent digital data of an inside of the blast furnace. The step of providing a computer comprises connecting the 3-D laser scanner to a computer having a point group analysis program. The step of calculating an outline of the top reactant stratum from the PGD is performed by the point group analysis program to calculate measure an outline of the top reactant stratum in the blast furnace from the PGD. At least one two-dimensional laser scanner is used to measure a path of the reactant being charged.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
With further reference to
The step of providing a 3-D laser scanner (100) comprises directing a 3-D laser scanner (20) at the reactant strata in the blast furnace (10) to scan the inside of the blast furnace (10). The 3-D laser scanner (20) outputs PGD that represent digital data of the inside of the blast furnace (10). The 3-D laser scanner may be mounted at the neck of the blast furnace (10) at a specific angle and may output PGD of the local coordinates in the blast furnace (10). Furthermore, the PGD may comprise the PGD of the outline of the top reactant stratum and the exposed inner surface of the blast furnace (10).
The step of providing a computer (101) comprises connecting a computer to the 3-D laser scanner (20) to obtain the PGD of the local coordinates in the blast furnace (10). The computer has an optional coordinate converting program and a point group analysis program.
The coordinate converting program converts the PGD of the local coordinates in the blast furnace (10) into PGD of the world coordinates.
The point group analysis program measures the outline of the top reactant stratum from the PGD.
The step of obtaining PGD (102) comprises sending the PGD output by the 3-D laser scanner (20) to the computer.
The step of converting the PGD (103) is performed by the coordinate converting program in the computer to convert the PGD of the local coordinates in the blast furnace (10) into the PGD of the world coordinates.
The step of calculating the outline of the top reactant stratum from the PGD (104) is performed by the point group analysis program in the computer to construct a model of the inside of the blast furnace (10) then calculate the outline of the top reactant stratum in the blast furnace (10) from the PGD.
A first embodiment of the coordinate converting program comprises steps of defining a main axis of the inside of the blast furnace, defining a rotational axis and a rotational angle and converting the PGD of the local coordinates in the blast furnace into the PGD of the world coordinates.
With reference to
The step of defining a rotational axis and rotational angle comprises defining a rotational axis vector {right arrow over (K)} and a rotational angle θ by equations
where vector {right arrow over (Z)} is a coordinate axis vector in the world coordinates and the rotational angle θ is an included angle between the vectors {right arrow over (A)} and {right arrow over (Z)}.
The step of converting the PGD of the local coordinates in the blast furnace into PGD of the world coordinates comprises rotating the points corresponding to the PGD of the local coordinates in the blast furnace (10) along the vector {right arrow over (K)} with the angle minus (−)θ to satisfy an equation P:Q′=(Q·K)K(1−cos θ)+Q cos θ−(K×Q)sin θ, wherein Q is the PGD of the local coordinates in the blast furnace (10) and Q′ is the PGD of the world coordinates.
Furthermore, a second embodiment of the coordinate converting program comprises steps of measuring a dip angle, defining a main axis of the inside of the blast furnace and a rotational axis and converting the PGD of the local coordinates in the blast furnace into the PGD of the world coordinates.
The step of measuring a dip angle is performed by an electronic spirit level to measure a dip angle θ, wherein the dip angle is an included angle between a coordinate axis vector {right arrow over (Z)} in the world coordinates and a main axis vector {right arrow over (A)} representing a main axis of the inside of the blast furnace.
The step of defining a main axis of the inside of the blast furnace comprises calculating the main axis vector {right arrow over (A)} representing a main axis of the inside of the blast furnace (10) from the equation
The step of defining a rotational axis comprises calculating a rotational axis vector {right arrow over (K)} from the equation
The step of converting the PGD of the local coordinates in the blast furnace into the PGD of the world coordinates comprises rotating the points corresponding to the PGD of the local coordinates in the blast furnace (10) along the vector {right arrow over (K)} with the angle −θ to satisfy the equation P:Q′=(Q·K)K(1−cos θ)+Q cos θ−(K×Q)sin θ, wherein Q is the PGD of the local coordinates in the blast furnace (10) and Q′ is the PGD of the world coordinates.
In addition, the point group analysis program further may determine a compression ratio of coke and a ratio of iron ore to coke and may comprise steps of constructing a model of the inside of the blast furnace, separating the PGD of the outline of the top reactant stratum from the PGD of the inner surface of the blast furnace, optionally determining a compression ratio of the coke stratum and a ratio of the iron ore stratum to the coke stratum.
The step of constructing a model of the inside of the blast furnace comprises constructing a model of the inside of the blast furnace (10) from the PGD.
The step of separating the PGD of the outline of the top reactant stratum from the PGD of the exposed inner surface of the blast furnace comprises sifting the PGD of the outline of the top reactant stratum from the PGD of the exposed inner surface of the blast furnace (10) in the model of the inside of the blast furnace (10) by using a cone equation (Z−ZC)2=α2((X−XC)2+(Y−YC)2), wherein (Xc, Yc, Zc) are coordinates at a peak of the cone shaped blast furnace (10) and a is an opening angle at the peak of the cone. The PGD of the exposed inner surface of the blast furnace (10) fits the cone equation (Z−ZC)2=α2 ((X−XC)2+(Y−YC)2) because the blast furnace (10) is cone shaped. Therefore, the outline of the top reactant stratum will remain in the model of the inside of the blast furnace (10) if the PGD of the exposed inner surface of the blast furnace (10) are eliminated.
With reference to
The step of determining a compression ratio of coke comprises acts of calculating the volume of the coke stratum, calculating the volume of the coke and iron ore strata and evaluating a compression ratio of the coke stratum.
The act of calculating the volume of a coke stratum comprises calculating the volume (V1) of the second reactant stratum (CN) from the PGD of the outline of the top reactant stratum by numerical integration after charging coke into the blast furnace (10).
The act of calculating the volume of the coke and the iron ore strata comprises calculating the volume (V2) of the second reactant stratum (CN) and the third reactant stratum (ON+1) by numerical integration after charging iron ore to form the third reactant stratum (ON+1) into the blast furnace (10), wherein the volume of the third reactant stratum (ON+1) is known to be V0.
The act of evaluating a compression ratio of the coke stratum is evaluated by an equation
With reference to
The act of calculating the thickness of each reactant stratum comprises calculating the thickness of each reactant stratum from the PGD of the outline of the top reactant stratum after charging each reactant into the blast furnace (10). For example, the thickness of each iron ore stratum is LOi, where i is an integer. In addition, the thickness of each coke stratum is LCi.
The act of calculating a ratio of iron ore to coke comprises is evaluated by an equation
wherein i=1, 2, 3 . . . .
Furthermore, the method for measuring a path of charging the reactant is an extension of the method for measuring an outline of a stratum of a reactant as described and comprise steps of providing at least one two-dimensional (2-D) laser scanner and calculating a path of the reactant being charged into the blast furnace.
With reference to
The step of calculating a path of charging the reactant comprises scanning the reactant spread by the feeder (40) and calculating a path of the reactant being charged. The two 2-D laser scanners (30) respectively have a left local coordinates and a right local coordinates, so the two local coordinates have to be corrected. A relationship between the left and right local coordinates represented by three parameters Px, Py, and θ.
The described Px, Py are determined by using a reflective board. The reflective board can be mounted on one of the 2-D laser scanners (30). Therefore, the parameters Px, Py will be determined when the 2-D laser scanner (30) without the reflective board measures the position of the 2-D laser scanner with the reflective board. The described angle θ is determined by the electronic spirit level.
With such a method, operators can easily measure the outline of the top reactant stratum in the blast furnace. Furthermore, the method can allow operators to determine whether the distribution of the coke and iron ore are as designated by operational procedures, by combining the outline of the top reactant layer in the blast furnace with the path of the reactant being charged.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.