RU72420U1 - X-RAY LUMINESCENT MINERAL SEPARATOR - Google Patents

Abstract

The utility model relates to the field of mineral processing, containing minerals that luminesce under the influence of x-ray radiation, namely, separators for the enrichment of crushed mineral material of large fractions, the size of which is comparable with the length of the excitation zone - registration of the separator. The proposed technical solution can be implemented both in separators for large fractions at all stages of enrichment, and in production control devices, for example, diamond-containing raw materials.

The technical result is an increase in the selectivity of x-ray luminescent separation of large-class minerals by eliminating the false extraction of related minerals and, as a result, increasing the content of useful mineral in the concentrate (improving the condition).

The X-ray luminescent mineral separator contains a transport mechanism, a pulse excitation source, a photodetector, an analog-to-digital converter (ADC), a command generation unit with an actuator, a luminescence component ratio value calculation unit made in the form of a programmable controller, the photodetector output is connected to the first ADC input, the output which is connected via the input / output bus to the input of the programmable controller, the first output of which is connected to the input of the command generation unit nogo mechanism.

Unlike the known one, a memory block of the previous values of the luminescence component ratio and a device for comparing the values of the long-term luminescence component with a predetermined threshold value are connected to the separator, the second, third, fourth, fifth and sixth outputs of which are connected, respectively , with the second input of the comparison device, with the input of the pulse excitation source, with the control inputs for reading and writing of the memory block and with the second input of the ADC, the output stroystva comparison connected to the second input of the programmable controller, the programmable controller is additionally provided to determine the sign of the difference between the current value and the ratio of the luminescence component values stored in the memory unit.

Description

The proposed utility model relates to the field of mineral processing, containing minerals that luminesce under the influence of x-ray radiation, and in particular to separators for the enrichment of crushed mineral material of large fractions, the size of which is comparable with the length of the excitation zone - registration of the separator. The proposed technical solution can be implemented both in separators for large fractions at all stages of enrichment, and in devices for controlling products, for example, diamond-containing raw materials.

Luminescence of minerals includes at least two components: short, which occurs simultaneously with the appearance of x-ray radiation and goes out almost immediately after its disappearance, and long, which flares up during irradiation of the mineral with x-ray radiation and gradually goes out for some time after the end of irradiation. The kinetics of acceleration - attenuation of luminescence is different for different minerals.

To increase the selectivity of the extraction of the enriched mineral in known X-ray luminescent separators, various ratios of the kinetic characteristics of the luminescence signal recorded both during and after exposure to excitation radiation are used as a separation criterion.

For example, a device is known that implements a method (SU 1603588 A1, B07C 5/342, 08.20.1999.), Comprising irradiating the starting material with X-ray pulses to excite the luminescence of a useful mineral, measuring the intensities of the short and long components of the luminescence excited in it, and isolating the useful mineral from the source material for a given ratio of the measured intensity levels, selected as a separation criterion. The intensity levels are measured during the exciting pulse - l ₁ and with a delay relative to the exciting pulse - l ₂ , and the separation of minerals is carried out, for example, when the relation

l ₂ / (l ₁ -l ₂ ) <0.17. The value of the short component of the luminescence signal is determined in this device by subtraction (l ₁ -l ₂ ).

However, when conducting such measurements, it is very difficult to obtain the minimum necessary error, which negatively affects the selectivity of the extraction of minerals using this device.

The closest analogue of the proposed utility model is an X-ray luminescent mineral separator (RU No. 2236311 C1, B07C 5/342, B03B 13/06, 09/20/2004.), Containing a transport mechanism, a pulse excitation source, a photodetector, a luminescence signal processing unit, made in the form an analog-to-digital converter (ADC), a unit for calculating the value of the ratio of the luminescence components, made in the form of a programmable controller, and a unit for generating commands with an actuator. The output of the photodetector is connected to the first input of the ADC, the output of which is connected via the I / O bus to the input of the programmable controller, the first output of which is connected to the input of the actuator command generation block. To synchronize the operation of the separator systems, the first output of the pulse excitation source is connected to the first input of the programmable controller and to the second input of the analog-to-digital converter, the output of which is connected to the second input of the programmable controller. The photodetector can be installed on the side of the incident x-ray radiation or on the side opposite to the incident x-ray radiation. The criterion for the separation of diamonds and associated luminescent minerals in the separator is the ratio of the total intensity of the short and long components of the luminescence, which is measured during the action of the exciting pulse, to the intensity of the long component of the luminescence, measured after a specified time after the end of the exciting pulse. If the obtained value of the ratio is less than the specified threshold, then a decision is made that the mineral is “useful”, and if it is greater than the threshold, then the mineral is considered “concomitant”.

A separator using this separation criterion can give good results on selectivity with the mineral in the excitation-recording zone of luminescence unchanged, since in this case the value of the ratio adopted as the separation criterion does not change when the mineral is sequentially irradiated with several x-ray pulses.

However, the luminescent mineral moves with the material and enters the excitation-recording zone of luminescence asynchronously with respect to the excitation pulses. When mineral material of large fractions is separated, when the size of the mineral is comparable with the length of the excitation-registration zone in the direction of movement of the material, the effect of false detection of a “useful mineral” appears. Let us consider this effect in relation to a concomitant mineral, in which the value of the criterion is greater than the threshold. As the mineral moves through the excitation-registration zone, the measured value of the long-term luminescence component, including at the output of the ADC, increases slightly, but the value of the separation criterion (the ratio of the components determined by the controller from the output of the ADC) remains above the threshold value. Therefore, a mineral is defined as "concomitant." But at the exit of the mineral from the excitation-registration zone, the intensity of the short component drops sharply, and the value of the criterion (component ratio) also decreases and becomes less than the threshold. As a result, when a mineral leaves the excitation-registration zone, the same mineral is falsely defined as “useful” and, by the signal of the controller, it is separated into the concentrate by the actuator by the actuator, which reduces the separation selectivity.

The technical result of the proposed useful solution model is to increase the selectivity of large-class X-ray separation of minerals by eliminating the false extraction of related minerals and, as a result, increasing the content of the useful mineral in the concentrate (improving condition).

The achievement of the technical result is provided by the proposed X-ray-luminescent separator containing a transporting mechanism, a pulse excitation source, a photodetector, an analog-to-digital converter (ADC), a command generation unit with an actuator, a luminescence component ratio value calculation unit made in the form of a programmable controller, a photodetector output connected to the first input of the ADC, the output of which is connected via the I / O bus to the input of the programmable controller, the first output of which connected to the input of the actuator command generation block, while the separator additionally contains a memory block of the previous values of the luminescence component ratio and a device for comparing the values of the long-term luminescence component with a predetermined threshold

values connected to the input / output bus of the programmable controller, the second, third, fourth, fifth and sixth outputs of which are connected, respectively, with the second input of the comparison device, with the input of the pulse excitation source, with the control read and write inputs of the memory block and with the second input of the ADC , the output of the comparison device is connected to the second input of the programmable controller, while the programmable controller is further equipped with the ability to determine the sign of the difference between the current value of the comp luminescence term and values stored in the memory block.

In contrast to the known one, the proposed X-ray luminescent separator additionally contains a memory unit for the previous values of the luminescence component ratio and a device for comparing the values of the long-term luminescence component with a predetermined threshold value, connected to the input / output bus of the programmable controller, the second, third, fourth, fifth and sixth outputs of which are connected , respectively, with the second input of the comparison device, with the input of the pulse excitation source, with control read and write inputs and in the memory and with the second input of the ADC, the output of the comparison device is connected to the second input of the programmable controller, while the programmable controller is additionally equipped with the ability to determine the sign of the difference between the current value of the ratio of the luminescence components and the values stored in the memory unit.

The photodetector in the separator can be installed on the side of the incident x-ray radiation or on the side opposite to the incident x-ray radiation.

Figure 1 presents the functional diagram of the proposed separator

2, timing diagrams:

13 - start pulses of the pulse excitation source;

14 - start pulses at the second input of the ADC;

15 - luminescence signals at the output of the photodetector (at the first input of the ADC) and the voltage threshold value of the long-term component of the luminescence signal;

16 - signals at the output of the comparison device;

17 - recording pulses at the inputs of the memory block;

18 - read pulses at the inputs of the memory block;

19 - control signals to the block generating commands for the actuator.

The X-ray luminescent separator shown in Fig. 1 comprises a hopper 1, a transport mechanism 2, a pulse excitation source 3 with an X-ray tube (not shown in Fig. 1), a photodetector 4, an ADC 5, a command generation unit 6 with an actuator (for example, an air ejector), concentrate storage device 7, 8 tail storage device, programmable controller 9, input / output bus 10, memory unit 11 of the previous value of the ratio of the luminescence component and device 12 for comparing the values of the long-term luminescence component with a given threshold th value. The transporting mechanism 2 can be made in the form of an inclined tray and / or vibratory feeder. The photodetector 4 can be installed above the stream of separated material both from the side of the incident X-ray radiation and from the side opposite to the incident X-ray radiation. Programmable controller 9 performs the function of a unit for calculating the value of the ratio of the luminescence components. The output of the photodetector 4 is connected to the first input of the ADC 5, the output of which is connected via the input / output bus 10 with the first input of the programmable controller 9; a memory unit 11 and a comparison device 12 are also connected to the I / O bus 10. The second, third, fourth, fifth and sixth outputs of the programmable controller 9 are connected, respectively, with the second input of the comparison device 12, with the input of the pulse excitation source 3, with the control inputs for reading Rd and writing Wr of the memory block 11, and with the second input of the ADC 5. The output of the comparison device 12 is connected to the second input of the controller 9. The programmable controller 9 is provided with the ability to determine the sign of the difference between the current ratio value of the luminescence components and the ratio values stored in the memory unit 11.

X-ray luminescent mineral separator, shown in figure 1, operates as follows. Before starting work, the following data are stored in the memory of programmable controller 9: threshold (minimum) value of the long-term luminescence component of a useful mineral (for example, diamond), delay interval for determining the value of a long-term component, threshold (maximum) value of the ratio of the luminescence components of a useful mineral (the ratio of the sum of the short and long-term component to the value of the long-term component).

After turning on the power of the separator, the programmable controller 9 starts issuing from the output 3 pulses 13 (Fig.2) start to the input of the source 3, which with the help of its x-ray tube (RT) forms pulses of x-ray radiation. The transporting mechanism 2 continuously delivers the separated material (for example, diamond-containing) into the excitation zone - registration, on which the radiation pulses of the RT fall.

Under the influence of X-ray radiation of RT, luminescence of diamonds and some associated minerals occurs. The optical luminescence signal hits the input of the photodetector 4 and the electric signal 15 (Fig. 2) from its output goes to the first input of the ADC 5, the second input of which receives pulses 14 (Fig. 2) from the output 6 of the programmable controller 9. At times t = t _2n , corresponding to the end of the excitation pulse, the launch of the ADC 5 provides the transmission to the programmable controller 9 of the total intensity value of the short and long components of the luminescence ignition. At time t = t _{2n + 1} , corresponding to the delay relative to the end of the excitation pulse for a time (t _{2n + 1} -t _2n ), the ADC 5 starts transmitting to the programmable controller 9 the values of the long-term luminescence decay component. On the data bus 10, codes for the values of the sum of the short and long components (ignition) and codes for the values of the long component (attenuation) are received from the output of the ADC 5 at the first input of the programmable controller 9 and at the input of the comparison device 12. The second input of the comparison device 12 from the output 2 of the programmable controller 9 receives a signal in the form of a threshold code of the continuous component. Its value Uп in the scale of the luminescence signal is shown in diagram 15 of FIG. 2. If the code of the value of the long-term component of the luminescence signal at time t = t _{2n + 1} exceeds the code of its threshold value Uп, a signal 16 is generated at the output of the comparison device 12 (figure 2), which is sufficient for the controller 9 to register. Signal 16 is received to the second input of the programmable controller 9. When the signal 16 enters the programmable controller 9, the latter calculates the ratio of the components according to the values of the ADC 5 output code obtained at time instants t = t _2n and t = t _{2n + 1} , and writes this value to the block 11 memory ty through bus 10 by feeding output 5 to the input of block 11 of the write signal Wr (diagram 17 of FIG. 2). If at time t = t _{2n + 1 the} signal 16 is absent, then the ratio value equal to zero is written to the memory block 11. After writing to the memory block 11 the current ratio value, programmable

controller 9 proceeds to analyze the possible detection of a useful mineral. The analysis involves several criteria:

- if signal 16 is absent, i.e. in this excitation period, the long-term component is less than the threshold, the analysis stops and signal 19 (Fig. 2) is not issued to block 6;

- if the signal 16 is present, but the value of the component ratio in the current period is greater than the threshold value, the signal 19 (figure 2) is also not issued;

- if signal 16 is present and the ratio of the components in the current period is less than its threshold value, then the programmable controller 9 analyzes “n” the previous (for definiteness two) values of the ratio of the components of the luminescence. To do this, the controller 9 from the output 4 twice gives the read signal Rd (diagram 18 of FIG. 2), while on the bus 10 from the memory block 11 “n” of the previous (for definiteness two) values of the component ratio are read out and the programmable controller 9 determines the sign of the difference between the current value of the component relationship and the values read from the memory block 11. If the difference sign in all "n" cases is positive, then signal 19 is sent to block 6 (Fig. 2), and if the difference sign is negative, then signal 19 is not issued.

Consider now the reaction of the programmable controller 9 to the luminescence signals after the excitation pulses 13 (figure 2):

- After the first and second excitation pulses 13, the signal of the long-term component 15 is less than the threshold Uп and the output signal of the comparison device 12 is absent, the signal 17 writes the value of the component-zero ratio to the memory unit 11.

- After the third pulse 13 at time t _{5, the} signal 15 of the long-term component is greater than the threshold Uп, therefore, the signal 16 is received from the output of the comparison device 12 to the input 2 of the programmable controller 9. The controller 9 calculates the ratio value of the luminescence components and writes it by the pulse 17 to the memory unit 11 . Then, the controller 9 with two pulses 18 sequentially reads from the memory block 11 the previous values of the relations of the components. Since these relations are written in zeros, the signs of the difference between the current and previous values are positive. All conditions for the detection of a useful mineral are fulfilled. The controller 9 generates a signal 19 in block 6. If the luminescence signal of the "diamond" is observed after the next pulse, its analysis does not represent

interest because a signal for its separation in the accumulator 7 of the concentrate is already formed.

- The reaction of the controller 9 to the fourth excitation pulse is similar to the reaction to the first and second (luminescence signal 15 below the threshold Uп).

- After the fifth excitation pulse 13, the signal 15 of the long-term component is greater than the threshold Uп - signal 16 is formed, and the ratio of the luminescence components exceeds the threshold set for it; the control signal 19 is not generated in block 6, but the ratio value is recorded by signal 17 in the memory block 11.

- The reaction after the sixth pulse is similar to the reaction to the fifth pulse - the ratio of the luminescence components exceeds the threshold set for it, so the signal 19 is not formed, but the ratio of the components of the signal 17 is recorded in the memory unit 11.

- After the seventh pulse of excitation 13, the signal 15 of the long-term component is greater than the threshold Uп - signal 16 is formed, the ratio of the luminescence components does not exceed the threshold set for it (a large mineral begins to leave the excitation zone - registration and the intensity of the short luminescence component decreases), but read from the block 11 of the memory by signal 18, the previous values of the component ratio exceed its current value, therefore, the determined value of the difference between the current and previous has a negative sign. As a result, due to the failure to fulfill the last condition for detecting a useful mineral, signal 19 is not formed, and the mineral enters the 8-tail storage ring (false extraction does not occur).

Thus, the proposed X-ray luminescent mineral separator ensures the achievement of a technical result by taking into account the sign of the change in the separation criterion during the entire time the mineral is present in the excitation zone — recording and eliminating from the consideration signals having an amplitude of the long-term component close to zero.

Claims (2)

1. An X-ray luminescent mineral separator containing a transport mechanism, a pulse excitation source, a photodetector, an analog-to-digital converter (ADC), a command generation unit with an actuator, a luminescence component ratio value calculation unit made in the form of a programmable controller, the photodetector output is connected to the first input ADC, the output of which is connected via the I / O bus to the input of the programmable controller, the first output of which is connected to the input of the unit for generating commands an individual mechanism, characterized in that the separator additionally contains a memory block of the previous values of the ratio of the luminescence components and a device for comparing the values of the long-term luminescence component with a predetermined threshold value, connected to the input / output bus of the programmable controller, the second, third, fourth, fifth and sixth outputs of which are connected respectively, with the second input of the comparison device, with the input of the pulse excitation source, with the control read and write inputs of the memory unit and with the second the ADC input, the output of the comparison device is connected to the second input of the programmable controller, while the programmable controller is additionally equipped with the ability to determine the sign of the difference between the current value of the ratio of the luminescence components and the values stored in the memory unit. 2. The separator according to claim 1, characterized in that the photodetector is installed on the side of the incident x-ray radiation or on the side opposite to the incident x-ray radiation.