Method and apparatus for handling dust separated from gases

Claim 2

Apparatus for collecting dry dust and handling the same comprisinsg a. chamber means for separating dust from gas under superatmospheric pressure, b. means for supplying water, c. means for mixing dust with water including holding receptacle means for holding the resulting slurry of dust and water, d. conduit means connecting the chamber means with the holding receptacle means for conducting dust from the chamber means to the holding receptacle means and imposing the superatmospheric gaseous pressure of the chamber means on the surface of the body of slurry in the holding receptacle means, the conduit means being the sole means of access of dust to the holding receptacle means above the surface of the body of slurry in the holding receptacle means, e. valve means for opening and closing the conduit means, f. slurry withdrawal conduit means connected to the holding receptacle means at a point near the lower end of the holding receptacle means, the slurry withdrawal conduit means including an upwardly extending portion extending to a point above the highest possible level of the body of slurry in the holding receptacle means and being open to the atmosphere at that point, g. overflow means connected to the upwardly extending portion of the slurry withdrawal conduit at said point for collecting slurry passing through the slurry withdrawal conduit and past said point, h. conduit means connected to the overflow means for passing slurry from the overflow means to a slurry processing apparatus, and i. shut-off valve means for closing slurry withdrawal conduit means (f) below said point.

Claim 3

APPARATUS FOR COLLECTING DRY DUST AND HANDLING THE SAME COMPRISING A. CHAMBER MENS FOR SEPARATING DUST FROM GAS UNDER SUPERATMOSPHERIC PRESSURE, B. MEANS FOR SUPPLYING WATER, C. MEANS FOR MIXING DUST WITH WATER INCLUDING HOLDING RECEPTACLE MEANS FOR HOLDING THE RESULTING SLURRY OF DUST AND WATER, D. CONDUIT MEANS CONNECTING THE CHAMBER MEANS WITH THE HOLDING RECEPTACLE MEANS FOR CONDUCTING DUST FROM THE CHAMBER MEANS TO THE HOLDING RECEPTACLE MEANS AND IMPOSING THE SUPERATMOSPHERIC GASEOUS PRESSURE OF THE CHAMBER MEANS ON THE SURFACE OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS,THE CONDUIT MEANS BEING THE SOLE MEANS OF ACCESS OF DUST TO THE HOLDING RECEPTACLE MEANS ABOVE THE SURFACE OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS, E. VALVE MEANS FOR OPENING AND CLOSING THE CONDUIT MEANS F. SLURRY WITHDRAWAL CONDUIT MEANS CONNECTED TO THE HOLDING RECEPTACLE MEANS AT A POINT NEAR THE LOWER END OF THE HOLDING RECEPTACLE MEANS, THE SLURRY WITHDRAWAL CONDUIT MEANS INCLUDING AN UPWARDLY EXTENDING PORTION EXTENDING TO A POINT ABOVE THE HIGHEST POSSIBLE LEVEL OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS AND BEING OPEN TO THE ATMOSPHERE AT THAT POINT,

Claim 4

APPARATUS FOR COLLECTING DRY DUST AND HANDLING THE SAME COMPRISING A. CHAMBER MENS FOR SEPARATING DUST FROM GAS UNDER SUPERATMOSPHERIC PRESSURE, B. MEANS FOR SUPPLYING WATER, C. MEANS FOR MIXING DUST WITH WATER INCLUDING HOLDING RECEPTACLE MEANS FOR HOLDING THE RESULTING SLURRY OF DUST AND WATER, D. CONDUIT MEANS CONNECTING THE CHAMBER MEANS WITH THE HOLDING RECEPTACLE MEANS FOR CONDUCTING DUST FROM THE CHAMBER MEANS TO THE HOLDING RECEPTACLE MEANS AND IMPOSING THE SUPERATMOSPHERIC GASEOUS PRESSURE OF THE CHAMBER MEANS ON THE SURFACE OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS,THE CONDUIT MEANS BEING THE SOLE MEANS OF ACCESS OF DUST TO THE HOLDING RECEPTACLE MEANS ABOVE THE SURFACE OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS, E. VALVE MEANS FOR OPENING AND CLOSING THE CONDUIT MEANS F. SLURRY WITHDRAWAL CONDUIT MEANS CONNECTED TO THE HOLDING RECEPTACLE MEANS AT A POINT NEAR THE LOWER END OF THE HOLDING RECEPTACLE MEANS, THE SLURRY WITHDRAWAL CONDUIT MEANS INCLUDING AN UPWARDLY EXTENDING PORTION EXTENDING TO A POINT ABOVE THE HIGHEST POSSIBLE LEVEL OF THE BODY OF SLURRY IN THE HOLDING RECEPTACLE MEANS AND BEING OPEN TO THE ATMOSPHERE AT THAT POINT,

Claim 5

The apparatus of claim 1 including j. second slurry withdrawal conduit means connected to first claimed slurry withdrawal conduit means (f) at a point lower than the upwardly extended portion of first claimed slurry withdrawal conduit means (f), k. shut-off valve means for closing the upwardly extending portion of the first claimed slurry withdrawal conduit means, and l. fully closable throttling valve means for controlling the second slurry withdrawal conduit means.

Claim 6

The apparatus of claim 1 including j. means for indicating a predetermined maximum slurry level in the holding receptacle means, k. means for indicating a predetermined lower slurry level in the holding receptacle means, l. means responsive to an indication of maximum slurry level acting to close valve means (e), and m. means responsive to an indication of lower slurry level acting to open valve means (e).

Claim 7

The apparatus of claim 1 including j. means for indicating a predetermined minimum slurry level in the holding receptacle, and k. means responsive to an indication of minimum slurry level acting to close valve means (i).

Claim 8

The apparatus of claim 1 in which j. the means for supplying water includes means for injecting the water into the holding receptacle means at a point below the surface of the body of slurry to keep the dust in suspension in the slurry in the holding receptacle means.

Claim 9

The apparatus oF claim 1 including j. means for injecting steam into the holding receptacle means to raise the pressure on the surface of the body of slurry in the holding receptacle means when valve means (e) are closed.

Claim 10

The apparatus of claim 1 including j. conduit means extending above said overflow means, the lower end of conduit means (j) being in communication with the overflow means and with the atmosphere at a higher point for receiving and containing a body of slurry rising above the overflow point and resting on the slurry in the slurry withdrawal conduit.

Claim 11

The apparatus of claim 2 including k. means for indicating a predetermined high slurry level in the holding receptacle, l. means for indicating a predetermined intermediate slurry level in the holding receptacle, m. means responsive to an indication of high slurry level acting to close valve means (e), and n. means responsive to an indication of intermediate slurry level acting to open the valve means (e).

Claim 12

The apparatus of claim 2 including k. means for indicating a predetermined minimum slurry level in the holding receptacle, and l. means responsive to an indication of minimum slurry level acting to close valve means (i).

Claim 13

The apparatus of claim 2 including k. the means for supplying means including means for injecting the water into the receptacle at a point below the surface of the body of slurry to keep the dust in suspension in the slurry in the holding receptacle means.

Claim 14

The apparatus of claim 2 including k. means for injecting steam into the holding receptacle means to raise the pressure on the surface of the body of slurry in the holding receptacle means.

Claim 15

Apparatus for collecting dry dust and handling the same comprising a. chamber means for separating dust from gas under superatmospheric pressure, b. means for supplying water, c. means for mixing dust with water including receptacle means for holding the resulting slurry of dust and water, d. conduit means connecting the chamber means with the holding receptacle means for conducting dust from the chamber means to the holding receptacle means and imposing the superatmospheric gaseous pressure of the chamber means on the surface of the body of slurry in the holding receptacle means, the conduit means being the sole means of access of dust to the holding receptacle means above the surface of the body of slurry in the holding receptacle means, e. valve means for opening and closing the conduit means, f. slurry withdrawal conduit means connected to the holding receptacle means at a point near the lower end of the holding receptacle means, g. means associated with the slurry withdrawal conduit means for controlling flow of slurry through the slurry withdrawal conduit, h. conduit means connected to the withdrawal conduit means downstream of means (g) relative to slurry flow for passing slurry to a slurry thickener apparatus.

Claim 16

Apparatus for collecting dry dust and handling the same comprising a. chamber means for separating dust from gas under superatmospheric pressure, b. means for supplying water, c. means for mixing dust with water including receptacle means for holding the resulting slurry of dust and water, d. conduit means connecting the chamber means with the holding receptacle means for conducting dust from the chamber means to the holding receptacle means and imposing the superatmospheric gaseous pressure of the chamber means on the surface of the body of slurry in the holding receptacle means, the conduit means being the sole means of access of dust to the holding receptacle means above the surface of the body of slurry in the holding receptacle means, e. valve means for opening and closing the conduit means, f. slurry withdrawal conduit means connected to the holding receptacle means at a point near the lower end of the holding receptacle means, g. means associated with the slurry withdrawal conduit means for controlling flow of slurry through the slurry withdrawal conduit, h. conduit means connected to the withdrawal conduit means downstream of means (g) relative to slurry flow for passing slurry to a slurry thickener apparatus.

Claim 17

The apparatus of claim 12 including i. means for indicating a predetermined maximum slurry level in the holding receptacle, j. means for indicating a predetermined high slurry level in the holding receptacle, k. means for indicating a predetermined minimum slurry level in the holding receptacle, l. means responsive to an indication of maximum slurry level acting to close valve means (e), m. means responsive to an indication of high slurry level acting to open means (g), and n. means responsive to an indication of minimum slurry level acting to close means (g).

Claim 18

The apparatus of claim 12 including i. means for indicating a predetermined high slurry level in the holding receptacle, j. means for indicating a predetermined intermediate slurry level in the holding receptacle, k. means responsive to an indication of high slurry level acting to close valve means (e), and l. means responsive to an indication of intermediate slurry level acting to open valve means (e).

Claim 19

The apparatus of claim 12 including i. means for indicating a predetermined minimum slurry level in the holding receptacle, and j. means responsive to an indication of minimum slurry level acting to close means (g).

Claim 20

The apparatus of claim 12 in which i. the means for supplying water include means for injecting the water into the receptacle at a point below the surface of the body of slurry to keep the dust in suspension in the slurry in the holding receptacle means.

Claim 21

The apparatus of claim 12 including i. means for injecting steam into the holding receptacle means to raise the pressure on the surface of the body of slurry in the holding receptacle means when valve means (e) are closed.

Claim 22

The apparatus of claim 12 in which i. means are associated with means (g) making means (g) adjustable to obtain a desired throttling action in means (g) to control the rate of withdrawal of the slurry from the holding tank.

Claim 23

The apparatus of claim 18 including j. means for indicating a predetermined high slurry level in the holding receptacle, k. means for indicating a predetermined intermediate slurry level in the holding receptacle, j. means responsive to an indication of high slurry level acting to close valve means (e), and m. means responsive to an indication of intermediate slurry level acting to open valve means (e).

Claim 24

The apparatus of claim 18 including j. means for indicating a predetermined minimum slurry level in the holding receptacle, and k. means responsive to an indication of minimum slurry level acting to close means (g).

Claim 25

The apparatus of claim 18, in which j. the means for supplying water include means for injecting the water into the receptacle at a point below the surface of the body of slurry to keep the dust in suspension in the slurry in the holding receptacle means.

Claim 26

The apparatus of claim 18 including j. means for injecting steam into the holding receptacle means to raise the pressure on the surface of the body of slurry in the holding receptacle means when valve means (e) are closed.

Claim 27

The apparatus of claim 12 including i. high pressure slurry transmission conduit means interposed between the means (g) and the thickener apparatus, and j. check valve means between the high pressure slurry transmission conduit means and the holding receptacle means for preventing back flow of slurry from the high pressure slurry transmission conduit means to the holding receptacle.

Claim 28

The apparatus of claim 12 including i. means for indicating a predetermined high slurry level in the holding receptacle, j. means for indicating a predetermined low slurry level in the holding receptacle, k. means responsive to an indication of high slurry level acting to close valve means (e) and open valve means (g) and l. means responsive to an indication of low slurry level acting to open valve means (e) and close means (g).

Claim 29

The apparatus of claim 24 in which k. the means for supplying water includes means for injecting the water into the receptacle at a point below the surface of the body of slurry to keep the dust in suspension in the slurry in the holding receptacle means.

Claim 30

The apparatus of claim 24 including k. means for injecting steam into the holding receptacle means to raise the pressure on the surface of the body of slurry in the holding receptacle means.

Claim 31

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of slurry and keeping the dust in suspension in the body of slurry by injection Of the water into the receptacle under a pressure greater than the gaseous superatmospheric pressure on the exposed surface of the body of slurry, at least some of the water being injected below the exposed surface of the body of slurry, d. forming a column of slurry supported on the body of slurry in the receptacle, the top surface of the slurry in the column being exposed to atmospheric pressure, the column of slurry extending above the level of the exposed surface of the body of slurry in the receptacle to a predetermined height such as to act as a controlling factor on the level of the exposed surface of the body of slurry in the receptacle, e. drawing off slurry by gravity from the top of the column of slurry at and above the predetermined height at a rate determined by the pressure differential between the superatmospheric gaseous pressure on the exposed surface of the body of slurry and atmospheric pressure and by the rate of formation of slurry in the receptacle and f. passing slurry so drawn off to a slurry processing step.

Claim 32

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of slurry and keeping the dust in suspension in the body of slurry by injection Of the water into the receptacle under a pressure greater than the gaseous superatmospheric pressure on the exposed surface of the body of slurry, at least some of the water being injected below the exposed surface of the body of slurry, d. forming a column of slurry supported on the body of slurry in the receptacle, the top surface of the slurry in the column being exposed to atmospheric pressure, the column of slurry extending above the level of the exposed surface of the body of slurry in the receptacle to a predetermined height such as to act as a controlling factor on the level of the exposed surface of the body of slurry in the receptacle, e. drawing off slurry by gravity from the top of the column of slurry at and above the predetermined height at a rate determined by the pressure differential between the superatmospheric gaseous pressure on the exposed surface of the body of slurry and atmospheric pressure and by the rate of formation of slurry in the receptacle and f. passing slurry so drawn off to a slurry processing step.

Claim 33

A method as claimed in claim 27 including g. predetermining an upper limit and an intermediate point for the level of the exposed surface of the body of slurry in the receptacle, h. increasing the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the upper limit to increase the pressure differential between the pressure on the surface of the body of slurry and atmospheric pressure and increase the rate of slurry drawn off from the receptacle, and i. lowering the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the intermediate point.

Claim 34

The method claimed in claim 28 in which j. the gaseous pressure on the exposed surface of the body of slurry is increased by sealing off the receptacle above the level of the exposed surface of the body of slurry and continuing to inject water under a pressure greater than the gaseous pressure on the exposed surface of the body of slurry in the receptacle at the time the body of slurry reaches the upper limit.

Claim 35

The method of claim 28 in which j. the dust is separated from the gases in a chamber and dust is transferred to the receptacle by conduit means constituting the only means of access of dust to the receptacle above the level of the exposed surface of the body of slurry and the receptacle is sealed off by closing the conduit means, k. the gaseous pressure on the surface of the body of slurry is lowered by opening the conduit means.

Claim 36

The method of claim 28 in which j. the gaseous pressure on the exposed surface of the body of slurry is increased by sealing off the receptacle above the level of the exposed surface of the body of slurry and injecting into the receptacle steam under a pressure greater than the gaseous pressure on the exposed surface of the body of slurry in the receptacle at the time the level of the body of slurry reaches the upper limit.

Claim 37

The method of claim 31 in which k. the dust is separated from the gases in a chamber and dust is transferred to the receptacle by conduit means constituting the only means of access of dust to the receptacle above the level of the exposed surface of the body of slurry and the receptacle is sealed off by closing the conduit means, l. the gaseous pressure on the surface of the body of slurry is lowered by opening the conduit means.

Claim 38

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of slurry, d. withdrawing slurry through conduiT from a point in the receptacle below the exposed surface of the body of slurry, e. with the surface of the body of slurry in the receptacle exposed to superatmospheric gaseous pressure throttling the flow of slurry through the conduit to maintain a flow rate through the conduit which will maintain the level of the exposed surface of the slurry in the receptacle at a level above the point of withdrawal of the slurry from the receptacle and below a point at which the receptacle will overflow, and f. passing withdrawn slurry to a slurry processing step.

Claim 39

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of slurry, d. withdrawing slurry through conduiT from a point in the receptacle below the exposed surface of the body of slurry, e. with the surface of the body of slurry in the receptacle exposed to superatmospheric gaseous pressure throttling the flow of slurry through the conduit to maintain a flow rate through the conduit which will maintain the level of the exposed surface of the slurry in the receptacle at a level above the point of withdrawal of the slurry from the receptacle and below a point at which the receptacle will overflow, and f. passing withdrawn slurry to a slurry processing step.

Claim 40

The method claimed in claim 33 including g. predetermining an upper limit and an intermediate point for the level of the exposed surface of the body of slurry in the receptacle, h. increasing the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the upper limit, and i. lowering the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the intermediate point.

Claim 41

The method claimed in claim 34 in j. the gaseous pressure on the exposed surface of the body of slurry is increased by sealing off the receptacle above the level of the exposed surface of the body of slurry and continuing to inject water under a pressure greater than the gaseous pressure on the exposed surface of the body of slurry in the receptacle at the time the body of slurry reaches the upper limit.

Claim 42

The method of claim 35 in which k. the dust is separated from the gases in a chamber and dust is transferred to the receptacle by conduit means constituting the only means of access of dust to the receptacle above the level of the exposed surface of the body of slurry and the receptacle is sealed off by closing the conduit means, l. the gaseous pressure on the surface of the body of slurry is lowered by opening the conduit means.

Claim 43

The method claimed in claim 34 in which j. the gaseous pressure on the exposed surface of the body of slurry is increased by sealing off the receptacle above the level of the exposed surface of the body of slurry and injecting into the receptacle steam under a pressure greater than the gaseous pressure on the exposed surface of the body of slurry in the receptacle at the time the level of the body of slurry reaches the upper limit.

Claim 44

The method of claim 37 in which k. the dust is separated from the gases in a chamber and dust is transferred to the receptacle by conduit means constituting the only means of access to the receptacle above the level of the exposed surface of the body of slurry and the receptacle is sealed off by closing the conduit means, l. the gaseous pressure on the surface of the body of slurry is lowered by opening the conduit means.

Claim 45

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of slurry, d. providing conduit means for withdrawing slurry from the body of slurry in the receptacle, e. providing openable and closable valve means for controlling flow of slurry through the conduit means, f. predetermining an upper limit and a lower limit for the level of the exposed surface of the body of slurry in the receptacle, g. opening valve means (e) to cause slurry to flow from the body of slurry in the receptacle under the influence of the superatmospheric gas pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the upper limit, h. closing valve means (e) to stop flow of slurry from the body of slurry in the receptacle when the level of the body Of slurry reaches the lower limit, i. repeating the cycle of the last claimed two steps and j. passing slurry from the conduit means to a slurry processing step

Claim 46

The claim of claim 39 in which k. the dust is separated from the gases in a chamber and dust is transferred to the receptacle by second conduit means constituting the only means of access of dust to the receptacle above the level of the exposed surface of the body of slurry, and l. means are provided for closing the second conduit means to stop transfer of dust to the receptacle, m. the second conduit means are closed at the time valve means (e) are opened.

Claim 47

The method of claim 40 in which n. high pressure steam is injected into the receptacle simultaneously or after step (g) to cause the slurry to flow from the body of slurry in the receptacle.

Claim 48

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseouss pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. providing conduit means for withdrawing slurry from the body of slurry in the receptacle, d. providing a shut-off valve means for opening and closing the conduit means, e. closing the shut-off valve means when the level of slurry in the receptacle is low, f. continuing the formation of slurry in the receptacle until a high level of slurry in the receptacle is reached, g. sealing off the receptacle above the high level of slurry, h. raising the gas pressure on the surface of the body of slurry until a desired pressure is reached, i. maintaining a pressure on the body of slurry of at least the desired pressure, j. simultaneously with or after step (g) and before step (k) opening the shut-off valve, k. when the pressure on the body of slurry has forced slurry out of the receptacle to thereby lower the level of slurry to a desired low level closing the shut-off valve, i. repreating the cycle.

Claim 49

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseouss pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. providing conduit means for withdrawing slurry from the body of slurry in the receptacle, d. providing a shut-off valve means for opening and closing the conduit means, e. closing the shut-off valve means when the level of slurry in the receptacle is low, f. continuing the formation of slurry in the receptacle until a high level of slurry in the receptacle is reached, g. sealing off the receptacle above the high level of slurry, h. raising the gas pressure on the surface of the body of slurry until a desired pressure is reached, i. maintaining a pressure on the body of slurry of at least the desired pressure, j. simultaneously with or after step (g) and before step (k) opening the shut-off valve, k. when the pressure on the body of slurry has forced slurry out of the receptacle to thereby lower the level of slurry to a desired low level closing the shut-off valve, i. repreating the cycle.

Claim 50

The method of claim 42 in which l. back flow of slurry from the conduit means into the receptacle is prevented.

Claim 51

The method of claim 42 in which l. the gaseous pressure on the exposed surface of the body of slurry in the receptacle is increased by injection of water into the receptacle.

Claim 52

The method of claim 44 in which m. back flow of slurry from the conduit means into the receptacle is prevented.

Claim 53

The method of claim 42 in which l. the gaseous pressure on the exposed surface of the body of slurry in the receptacle is increased by injection of steam into the receptacle.

Claim 54

The method of claim 46 in which m. back flow of slurry from the conduit means into the receptacle is prevented.

Claim 55

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of a slurry, d. withdrawing slurry from the receptacle into the ambient atmosphere through a conduit from a point in the receptacle below the exposed surface of the body of slurry, e. with the surface of the body of slurry in the receptacle exposed to superatmospheric gaseous pressure, and the withdrawn slurry exposed to atmospheric pressure controlling the rate of flow of slurry through the conduit to obtain a flow rate through the conduit which will maintain the of the exposed surface of the slurry in the receptacle within a range of levels above the pOint of withdrawal of the slurry from the receptacle and below a point at which the receptacle will overflow, f. passing withdrawn slurry to a slurry processing step, g. predetermining an upper limit and a lower limit for the level of the exposed surface of the body of slurry in the receptacle, h. increasing the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the upper limit to increase the pressure differential between the pressure on the surface of the body of slurry and atmospheric pressure and increase the rate of flow of slurry drawn off from the receptacle, and i. stopping the withdrawal of slurry from the receptacle when the level of the body of slurry in the receptacle reaches the lower limit.

Claim 56

Method for collecting dry dust and handling the same comprising a. continuously separating dust from dust laden gases under superatmospheric pressure, b. forming a slurry of dust in water and collecting slurry in a receptacle closed to the ambient atmosphere but open to a superatmospheric gaseous pressure, the slurry forming a body of slurry having a surface exposed to superatmospheric gaseous pressure, c. adding water to the receptacle for the formation of a slurry, d. withdrawing slurry from the receptacle into the ambient atmosphere through a conduit from a point in the receptacle below the exposed surface of the body of slurry, e. with the surface of the body of slurry in the receptacle exposed to superatmospheric gaseous pressure, and the withdrawn slurry exposed to atmospheric pressure controlling the rate of flow of slurry through the conduit to obtain a flow rate through the conduit which will maintain the of the exposed surface of the slurry in the receptacle within a range of levels above the pOint of withdrawal of the slurry from the receptacle and below a point at which the receptacle will overflow, f. passing withdrawn slurry to a slurry processing step, g. predetermining an upper limit and a lower limit for the level of the exposed surface of the body of slurry in the receptacle, h. increasing the gaseous pressure on the exposed surface of the body of slurry when the level of the body of slurry reaches the upper limit to increase the pressure differential between the pressure on the surface of the body of slurry and atmospheric pressure and increase the rate of flow of slurry drawn off from the receptacle, and i. stopping the withdrawal of slurry from the receptacle when the level of the body of slurry in the receptacle reaches the lower limit.