US 11,697,854 B2 · Method for controlling the operation of a continuously or periodically operating centrifuge and device for conducting the method

Abstract

A method for controlling the operation of a continuously or periodically operating centrifuge can be employed in the sugar industry for separating crystalline carbohydrates or sugar alcohols from a crystal suspension called a magma or a mother liquor. The magma has a varying content of fine grain that is dependent on the properties of the pretreatment and of the raw material. Variable control values are provided in a control device of the centrifuge. One or plurality of sensors are provided that carry out the measurements in electromagnetic, optical, acoustic, and/or conductive ways. These measurements that are conducted serve for determining the fine grain fraction of the magma. The measurements are supplied as measurement signals to the control device of the centrifuge. The control device automatically analyzes the measurement signals supplied to it and evaluates them with respect to the fine grain content of the magma. The control device changes the variable control values of the centrifuge as a function of this evaluation.

Claims25

Dependent claims

A method for controlling the operation of a continuously or periodically operating centrifuge,

which is employed in the sugar industry for separating crystalline carbohydrates or sugar alcohols from a crystal suspension called a magma or a mother liquor,
wherein the magma has a varying content of fine grain that is dependent on the properties of the pretreatment and of the raw material,
with variable control values in a control device of the centrifuge,
is hereby characterized
in that one or a plurality of sensors are provided that carry out the measurements in electromagnetic, optical, acoustic, and/or conductive ways,
in that these measurements that are conducted serve for determining the fine grain fraction of the magma,
in that the measurements are supplied as measurement signals to the control device of the centrifuge,
in that the control device automatically analyzes the measurement signals supplied to it and evaluates them with respect to the fine grain content of the magma, and
in that the control device adjusts the variable control values of the centrifuge as a function of this evaluation,
in that a regulation established in advance in the control routines is provided as follows:
filling the centrifuge with more than 50% and less than 70% of a maximum filling load and at a predetermined first constant rotational speed (step V1);
after filling the centrifuge, increasing the rotational speed (step V2) to a second constant rotational speed (step V3);
maintaining the second constant rotational speed (step V3) for a predetermined period of time;
and
after maintaining the second constant rotational speed (step V3), increasing the rotational speed (step V4) to a third constant rotational speed (step V5).

12 more elements

A method for controlling the operation of a continuously or periodically operating centrifuge,

which is employed in the sugar industry for separating crystalline carbohydrates or sugar alcohols from a crystal suspension called a magma or a mother liquor,
wherein the magma has a varying content of fine grain that is dependent on the properties of the pretreatment and of the raw material,
with variable control values in a control device of the centrifuge,
is hereby characterized
in that one or a plurality of sensors are provided that carry out the measurements in electromagnetic, optical, acoustic, and/or conductive ways,
in that these measurements that are conducted serve for determining the fine grain fraction of the magma,
in that the measurements are supplied as measurement signals to the control device of the centrifuge,
in that the control device automatically analyzes the measurement signals supplied to it and evaluates them with respect to the fine grain content of the magma, and
in that the control device adjusts the variable control values of the centrifuge as a function of this evaluation,
in that the sensors for conducting the measurements for extracting the measurement signals in the course of flow of the magma are arranged before the centrifuge, in the drum and/or in the cover of the centrifuge and in the spray casing of the centrifuge individually or in redundant combinations of two or three,
in that a measurement signal is determined as a turbidity signal in front of a butterfly valve of the centrifuge, and
in that another sensor is provided as a laser sensor or radar sensor or spectrophotometer sensor in the drum or on the cover of the centrifuge, and a third sensor is provided for the conductivity or the color in the spray casing of the centrifuge, and
in that the sensor for the laser signal or the radar signal or the color signal and the sensor for the conductivity or the color are used as redundant secondary or tertiary measurement signals with a stepped, slight time delay.

10 more elements

A method for controlling the operation of a continuously or periodically operating centrifuge,

which is employed in the sugar industry for separating crystalline carbohydrates or sugar alcohols from a crystal suspension called a magma or a mother liquor,
wherein the magma has a varying content of fine grain that is dependent on the properties of the pretreatment and of the raw material,
with variable control values in a control device of the centrifuge,
is hereby characterized
in that one or a plurality of sensors are provided that carry out the measurements in electromagnetic, optical, acoustic, and/or conductive ways,
in that these measurements that are conducted serve for determining the fine grain fraction of the magma,
in that the measurements are supplied as measurement signals to the control device of the centrifuge,
in that the control device automatically analyzes the measurement signals supplied to it and evaluates them with respect to the fine grain content of the magma, and
in that the control device adjusts the variable control values of the centrifuge as a function of this evaluation,
in that a regulation established in advance in the control routines is provided as follows:
filling the centrifuge with more than 50% and less than 70% of the maximum filling load;
adjusting the rotational speed of the centrifuge during filling to 150 to 200 rpm;
omitting the conventional syrup covering;
after filling, increasing the rotational speed with adjustable acceleration curves dependent on the time course and/or dependent on the viscosity and/or dependent on the fine grain content of the magma up to a predetermined or defined rotational speed;
adding a first water blanket (WB) or optionally a plurality of water blankets staggered in time during this increase in the rotational speed;
optional conducting of an intermediate centrifuging step;
in this case, adding another water blanket (WB);
increasing the rotational speed to a predetermined or defined rotational speed;
keeping this rotational speed constant for approximately 5 to 40 seconds;
throttling the rotational speed in the case of an established imbalance;
subsequent repeated increasing of the rotational speed and, optionally, several repetitions of this step;
braking the centrifuge drum;
emptying the centrifuge drum;
and
conducting a screen washing.

22 more elements

A method for controlling the operation of a continuously or periodically operating centrifuge,

which is employed in the sugar industry for separating crystalline carbohydrates or sugar alcohols from a crystal suspension called a magma or a mother liquor,
wherein the magma has a varying content of fine grain that is dependent on the properties of the pretreatment and of the raw material,
with variable control values in a control device of the centrifuge,
is hereby characterized
in that one or a plurality of sensors are provided that carry out the measurements in electromagnetic, optical, acoustic, and/or conductive ways,
in that these measurements that are conducted serve for determining the fine grain fraction of the magma,
in that the measurements are supplied as measurement signals to the control device of the centrifuge,
in that the control device automatically analyzes the measurement signals supplied to it and evaluates them with respect to the fine grain content of the magma, and
in that the control device adjusts the variable control values of the centrifuge as a function of this evaluation,
in that a regulation established in advance in the control routines is provided as follows:
filling the centrifuge with more than 50% and less than 70% of the maximum filling load;
adjusting the rotational speed of the centrifuge during filling to 150 to 200 rpm;
omitting the conventional syrup covering;
after filling, linearly increasing the rotational speed up to 700 rpm;
adding a first water blanket (WB) during this linear increase in the rotational speed;
conducting an intermediate centrifuging step;
adding a second water blanket (WB);
increasing the rotational speed to 1,000 to 1,200 rpm;
keeping the rotational speed constant for approximately 15 to 40 seconds;
throttling the rotational speed in the case of an established imbalance;
subsequent repeated increase and, optionally, several repetitions of this step;
braking the centrifuge drum;
emptying the centrifuge drum;
and
conducting a screen washing.

22 more elements

Dependencies are inferred from the claim text.

Method for controlling the operation of a continuously or periodically operating centrifuge and device for conducting the method

Life of this patent

Method for controlling the operation of a continuously or periodically operating centrifuge and device for conducting the method

Life of this patent

Abstract

Claims25