Abstract: In a ferrocoke manufacturing method by shaping and carbonizing a mixture of coal and iron ore, a hardly softening coal having a button index (CSN) of not more than 2.0 is used as the coal. The coal can be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.0 and a volatile matter of not less than 17%, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is a range of 0.3-5.2. The coal can also be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.5-2.0, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is nit more than 5.0.

Abstract: A method for producing ferrocoke in which it is possible to use a cheap and poor-quality coal having a high ash content while suppressing the decrease of the strength in ferrocoke or formed coke and a special coal mixing is not performed with respect to the fusion frequently causing problems in the carbonization with the shaft furnace. In a method for producing ferrocoke by molding and carbonizing a mixture of coal and iron ore, the coal is a single coal or a mixture of plural coals and a non-caking or slight caking coal having a load average value of ash content of not less than 10.7% and a load average value of mean maximum reflectance of not less than 0.81% is used.

Abstract: In order to evaluate the compatibility of coals used in coke production and to produce cokes with desired strength by blending coals in consideration of the compatibility, the invention provides a technique which evaluates the adhesion strength obtained when two kinds of coals are carbonized based. on properties of the coals. Surface tensions of two kinds of semicokes obtained by heat treating two kinds of coals are measured. Based on the difference between the two measured values of surface tension, the quality of the adhesiveness between the two kinds of coals is evaluated.

Abstract: Provided is a method for preparing a coal mixture used for the purpose of producing coke with desired strength by taking into account the compatibility between coals for cokemaking. In the case of preparing a coal mixture, used as at least one portion of a coal blend for cokemaking, containing two or more types of coals with different surface tensions, the blending ratio of each of the coals is adjusted using the surface tension of a semicoke mixture obtained from the coal mixture as an indicator.

Abstract: In a control apparatus, a discharge control unit controls an igniter unit so that a flow of current from a primary coil towards a ground side is blocked, thereby generating a high voltage in a secondary coil, and controls a spark plug so that the spark plug generates electric discharge. An energy input control unit controls an energy input unit so as to input electrical energy to an ignition coil after the start of control of the spark plug by the discharge control unit. A control unit and an abnormality detecting unit detects an abnormality in the igniter unit or the ignition coil based on a first threshold and a first current value that is a value corresponding to a current detected by a current detection circuit at this time, when a first predetermined period elapses after the start of control of the spark plug by the discharge control unit.

Abstract: A method for producing ferrocoke in which it is possible to use a cheap and poor-quality coal having a high ash content while suppressing the decrease of the strength in ferrocoke or formed coke and a special coal mixing is not performed with respect to the fusion frequently causing problems in the carbonization with the shaft furnace. In a method for producing ferrocoke by molding and carbonizing a mixture of coal and iron ore, the coal is a single coal or a mixture of plural coals and a non-caking or slight caking coal having a load average value of ash content of not less than 10.7% and a load average value of mean maximum reflectance of not less than 0.81% is used.

Abstract: A method for producing a molded product for ferrocoke, wherein a high-strength molded product for ferrocoke can be produced advantageously without making particular investment in facilities and inviting the operating troubles. In a method for producing a molded product for ferrocoke by molding a mixed starting material of coal, an iron-source material, a high-softening point binder having a softening point of not lower than 150° C., and a low-softening point binder having a softening point of lower than 150° C., at least one of the iron-source material and the high-softening point binder is previously heated to not less than a temperature lower by 20° C. than a softening point of the high-softening point binder to perform molding of the mixture.

Abstract: Provided are, by using an index with which the influence on the strength of coke can be evaluated, a method for evaluating a weathering degree of coal and a coking property of weathered coal within the ranges in which the weathering degree and coking property cannot be determined by using conventional methods, and a method for controlling the weathering degree of coal with which it is possible to add weathered coal to a coal blend to be used for producing coke without decreasing the strength of coke by using the index. The weathering degree of coal is evaluated by using the surface tension of semicoke which is prepared by performing a heat treatment on weathered coal as an index. The weathering degree of each brand of coal is controlled so that the interfacial tension ?inter of a semicoke blend which is prepared by blending the plural brands of semicoke in accordance with the proportions is 0.03 mN/m or lower.

Abstract: A discharge control unit causes a high voltage to be generated in a secondary coil by controlling an igniter unit so as to block a flow of current from a primary coil towards a ground side, and controls a spark plug so that electric discharge is formed between electrodes of the spark plug. An energy input control unit controls an energy input unit to input electrical energy to an ignition coil after start of control of the spark plug by the discharge control unit. A normal ignition control unit controls ignition of an air-fuel mixture in a combustion chamber only through control of the spark plug by the discharge control unit. A specific ignition control unit controls the ignition of the air-fuel mixture in the combustion chamber through control of the spark plug by the discharge control unit and through control of the energy input unit by the energy input control unit.

Abstract: In a ferrocoke manufacturing method by shaping and carbonizing a mixture of coal and iron ore, a hardly softening coal having a button index (CSN) of not more than 2.0 is used as the coal. The coal can be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.0 and a volatile matter of not less than 17%, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is a range of 0.3-5.2. The coal can also be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.5-2.0, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is nit more than 5.0.

Abstract: In order to evaluate the compatibility of coals used in coke production and to produce cokes with desired strength by blending coals in consideration of the compatibility, the invention provides a technique which evaluates the adhesion strength obtained when two kinds of coals are carbonized based. on properties of the coals. Surface tensions of two kinds of semicokes obtained by heat treating two kinds of coals are measured. Based on the difference between the two measured values of surface tension, the quality of the adhesiveness between the two kinds of coals is evaluated.

Abstract: In order to evaluate the compatibility of coals used in coke production and to produce cokes with desired strength by blending coals in consideration of the compatibility, the invention provides a technique which evaluates the adhesion strength obtained when two kinds of coals are carbonized based on properties of the coals. Surface tensions of two kinds of semicokes obtained by heat treating two kinds of coals are measured. Based on the difference between the two measured values of surface tension, the quality of the adhesiveness between the two kinds of coals is evaluated.

Abstract: There is provided a method for blending coals for coke production, in which the strength of coke produced from a coal blend serving as a raw material is estimated using a physical property that has not been taken into consideration in the past as an index, so that the method is capable of suppressing an increase in the raw material cost of the coal blend and increasing the strength of coal. Two or more coal brands are blended together to provide a coal blend for coke production. When the two or more coal brands are blended together, the coal brands and the blending ratio of the coal brands are determined using the surface tension of each of the coal brands subjected to heat treatment, the surface tension serving as a control index.

Abstract: Provided is a technique by which the compatibility between coals for cokemaking can be quantitatively determined to estimate the coke strength taking into account the compatibility and to select and blend coals based on the coke strength estimated taking into account the compatibility, thereby allowing the production of a coke with the desired strength. A method for blending coals for cokemaking includes predicting the strength of a coke to be produced from a blend of a plurality of coals based on a difference between the surface tensions of the plurality of coals after heat treatment and determining the types and proportions of the coals to be blended.

Abstract: A spark plug for an internal combustion engine provided with a cylindrical housing, a ceramic insulator, a center electrode and a ground electrode. The ground electrode has a body base disposed from a front end surface of the cylindrical housing to a front end-side thereof. The ground electrode has a spark discharge gap formed therebetween itself and the center electrode. The body base is provided with pair of side-connecting surfaces which connect the inner surface and the outer surface. Each of the side-connecting surfaces having a side flat surface which is a flat surface parallel to an aligning direction of the center electrode and the body base. A distance between the pair of the side flat surfaces is a maximum width of the body base. A minimum distance between the inner surface and the side flat surface satisfies a relationship of 0.1 mm?L?0.5 mm, in the aligning direction.

Abstract: A spark plug for an internal combustion engine provided with a cylindrical housing, a ceramic insulator, a center electrode and a ground electrode. The ground electrode has a body base disposed from a front end surface of the cylindrical housing to a front end-side thereof. The ground electrode has a spark discharge gap formed therebetween itself and the center electrode. The body base is provided with pair of side-connecting surfaces which connect the inner surface and the outer surface. Each of the side-connecting surfaces having a side flat surface which is a flat surface parallel to an aligning direction of the center electrode and the body base. A distance between the pair of the side flat surfaces is a maximum width of the body base. A minimum distance between the inner surface and the side flat surface satisfies a relationship of 0.1 mm?L?0.5 mm, in the aligning direction.

Abstract: In a control apparatus, a discharge control unit controls an igniter unit so that a flow of current from a primary coil towards a ground side is blocked, thereby generating a high voltage in a secondary coil, and controls a spark plug so that the spark plug generates electric discharge. An energy input control unit controls an energy input unit so as to input electrical energy to an ignition coil after the start of control of the spark plug by the discharge control unit. A control unit and an abnormality detecting unit detects an abnormality in the igniter unit or the ignition coil based on a first threshold and a first current value that is a value corresponding to a current detected by a current detection circuit at this time, when a first predetermined period elapses after the start of control of the spark plug by the discharge control unit.

Abstract: A discharge control unit causes a high voltage to be generated in a secondary coil by controlling an igniter unit so as to block a flow of current from a primary coil towards a ground side, and controls a spark plug so that electric discharge is formed between electrodes of the spark plug. An energy input control unit controls an energy input unit to input electrical energy to an ignition coil after start of control of the spark plug by the discharge control unit. A normal ignition control unit controls ignition of an air-fuel mixture in a combustion chamber only through control of the spark plug by the discharge control unit. A specific ignition control unit controls the ignition of the air-fuel mixture in the combustion chamber through control of the spark plug by the discharge control unit and through control of the energy input unit by the energy input control unit.

Abstract: Coke is manufactured by blending two or more kinds of coal to form a coal blend and by carbonizing the coal blend. Interfacial tension among coal kinds is used as a control index for determining the blending ratio of each coal when forming the coal blend. It is possible to increase the strength of coke without increasing the material cost of a coal blend.

Abstract: Provided are, by using an index with which the influence on the strength of coke can be evaluated, a method for evaluating a weathering degree of coal and a coking property of weathered coal within the ranges in which the weathering degree and coking property cannot be determined by using conventional methods, and a method for controlling the weathering degree of coal with which it is possible to add weathered coal to a coal blend to be used for producing coke without decreasing the strength of coke by using the index. The weathering degree of coal is evaluated by using the surface tension of semicoke which is prepared by performing a heat treatment on weathered coal as an index. The weathering degree of each brand of coal is controlled so that the interfacial tension ?inter of a semicoke blend which is prepared by blending the plural brands of semicoke in accordance with the proportions is 0.03 mN/m or lower.