US2746297A - Apparatus for pulp sampling - Google Patents

Description

May 22, 1956 w. T. MARTIN APPARATUS FOR PULP SAMPLING Filed Aug. 12, 1955 FIG. 3

FIG. 5

DIIIIIIIIIIH! 40 FIG. 2

INVENTOR. WILLIAM T. MARTIN United States Patent APPARATUS FOR PULP SAMPLING William T. Martin, International Falls, .Minn., assignor to lVIinnesota and Ontario Paper Company, Minneapolis,

Application August 12, 19'53,SerialNo. 373,844

4 Claims. (Cl. 73-421) This invention relates to improvements in apparatus for sampling pulp during the digesting of lignocellulose material.

An object of this invention is to provide the means of determining progress of1he digestion of lignocellulose material during the digesting period without substantial loss of pressure and/0r digestion chemicals.

Other and further objects of the invention and the advantages of the same will be pointed out hereinafter and indicated "in the appended claims or will be obvious to one skilled in the art upon understanding the present disclosures.

For the purpose of the application there has been set forth one particular structure but it is to be understood that it is presented for illustrative purposes only and is not to be accorded any interpretation such as might have the effect of limiting what is claimed as the invention short of its true and comprehensive scope in the art.

For the manufacture of chemical pulp it is necessary (for the cooking liquor to penetrate the lignocellulose material such as wood) to reduce the chips to a size of about /2 inch to 1 inch long and about A; to inch thick. These chips are loaded into a suitable digester with the proper amount of digesting chemical. The digester after loading is closed and temperature and pressure applied until complete cooking has been accomplished. The time required for digesting varies with the types of pulp to be produced, types of lignocellulose material being cooked and so forth. The time for digesting varies from a few hours up to 10 and 12 or more hours. It is desirable to check the progress of digestion before the cooking cycle is complete. Heretofore it has been very difiicult to check the progress of digestion during cooking. In most instances no check of the digestion has been made until the lignocellulose material is discharge from the digester. At such time it is, of course, too late to do anything about the cooking. In accordance with the invention the lignocellulose material may be checked from time to time during digestion and if any alteration in the cooking cycle is required it may be accomplished.

In the drawings Figure 1 is a side elevational view of a digesting vessel with parts broken away;

Figure 2 is a side elevational view of a pulp sampling device by which the process may be carried out;

Figure 3 is a top plan view of the same;

Figure 4 is a view of a shower plate which is located adjacent the top of the pulp sampling device;

Figure 5 is a top plan view of a pulp gathering tray;

Figure 6 is a side elevational view of the same; and

Figure 7 is a sectional view through the sampling device shown in Figure 2.

The lignocellulose material, such as wood, in the proper form is fed into the digester 10 along with the digesting liquor. The normal procedure for cooking the lignocellulose material is carried out and during the digesting cycle sample of the material undergoing cooking is obtained by opening valve 14 in line 12 suitably connected to the digester. The pressure in the digester forces the material from the digester through line 12 into member '16 and then into the sampling device 18 tangentially to the walls thereof. At the time the valve 14 is open, water supplied under pressure is admitted through pipe 22 into the upper portion of the sampling device 18. The water passes through openings '30 in shower plate 26.

The sampling device 18 includes water receiving space 24 formed by shower plate 26 and top 28. Water is received in this space through conduit 22. Member 20 is secured to the top 28 and forms the inner walls of the shower space 24. The member 20 extends a distance into the space 17 and restricts the area into which the material is first received from the digester 10. In the lower end of space 17 is secured funnel-like member 34. Below the funnel-like member 34 is space 38 which receives the lignocellulose receiving tray 42. The sampling member 13 is provided with an opening 32 into which the tray 42'may be inserted and removed. Member 37 may be used for supporting the tray 42 in proper position-in space 38. Water from space 38 leaves the sampling device by discharge end 40.

The shower plate 26 is provided with a series of apertures 30. The drawing shows two rows of apertures but it is to be understood that any number of openings may be provided as long as sufiicient shower water can pass therethrough. It is preferred that the opening 32 be provided with a lip 36 to prevent splashing out of the openings of pulp and water. The tray 42 is provided with a foraminous bottom member 44. The pulp is deposited on the foraminous member and the water passes on to the discharge end 40. Tray 42 may be provided with a suitable handle 46.

In operation when a sample is desired the valve 14 is opened and the lignocellulose material from the digester is forced under pressure into the sampler 18 tangentially to the walls of the sampler and the member 20. The water flows into the shower space and passes through the openings 30 causing the cyclone lignocellulose material to fall through the space 17. The material passing through the restricted open end of the funnel-like member 34 results in depositing the material upon the foraminous bottom of the tray 42 without passing through the opening 32. The Water which passes through the tray is discharged through the end 49 which is usually connected to a suitable discharge line.

It is to be understood that the valve 14 is only open momentarily, for example, a few seconds each time so that the steam and gas release remains at a minimum. It is also to be understood that the sample from the digester may be blown into the sampler without the Water being on at the same time. The water for washing may be turned on after the sample has been taken from the digester, although the simultaneous obtaining of a sample and washing is the preferred method. If desired a vent could be used in connection with the sampler and if such vent is employed it would be secured to the top about the mid-portion of the member 20.

What is claimed is:

1. A device of the class described comprising a cylindrical vessel having a closed top and an opening on one side spaced from the top for receiving a foraminous bottom tray, a smaller diameter cylindrical member secured to the top and extending inside the vessel for less than half the length of the said Vessel, a shower plate secured to the walls of the vessel and spaced apart from the top to provide a water space, means for supplying water to the Water space, a funnel-like member secured inside the cylindrical vessel and spaced apart from the ends of the smaller diameter cylindrical member, said funnel-like member aligned substantially axially with the axis of the vessel and below the bottom of the smaller diameter cylindrical member and a foraminous collecting member positioned below the funnel-like member and a water discharge at one end of the cylindrical vessel and below the foraminous collecting member.

2. An upright cylindrical vessel having a closed top, a cylindrical member of about one-half the diameter of the cylindrical vessel and less than one-half the length secured to the top and extending into the vessel, a shower plate spaced from the top and secured between the wall of the cylindrical vessel and the cylindrical member, means for supplying water above the shower plate, means for discharging lignocellulose material below the shower plate and between the walls of the cylindrical vessel and the cylindrical member, a funnel-like member positioned substantially in axial alignment with the axis of the vessel and below and spaced apart from the lower end of the cylindrical member, and a screen bottom tray removably secured in the cylindrical vessel and below the funnelshaped member.

3. A sampler adapted to be placed in controlled communication with a pulp digester, the sampler comprising an upright closed top cylindrical vessel, a perforated plate secured to the vessel walls and spaced apart from the top to provide a water receiving space, means for supplying water to the water space, means for discharging lignocellulose material tangentially to the walls of the sampler below the perforated plate, a funnel-like member positioned in the sampler and spaced apart from the shower plate, said funnel-like member being in substantially axial alignment with the axis of the vessel, and a removable foraminous bottom tray positioned below the funnelshaped member for receiving lignocellulose material and permitting water to pass therethrough.

4. A cylindrical vessel having a closed end and an open end, a smaller diameter cylindrical member secured within the vessel and to the closed end, said smaller diameter member of considerably shorter length than the vessel, a perforated plate spaced apart from the closed end of the vessel and secured between the walls of the vessel and the smaller diameter cylindrical member to provide a water receiving space, means for supplying Water to said water receiving space, means for discharging lignocellulose material below the perforated plate tangentially to the walls of the cylindrical vessel, a removable foraminous bottom tray for collecting lignocellulose material, said tray positioned in the cylindrical vessel between the perforated plate and the open end of the cylindrical vessel.

References Cited in the file of this patent UNITED STATES PATENTS 2,615,339 Holgersson et al Oct. 28, 1952 FOREIGN PATENTS 376,678 Germany June 1, 1923

Claims (1)

1. A DEVICE OF THE CLASS DESCRIBED COMPRISING A CYLINDRICAL VESSEL HAVING A CLOSED TOP AND AN OPENING ON ONE SIDE SPACED FROM THE TOP FOR RECEIVING A FORAMINOUS BOTTOM TRAY, A SMALLER DIAMETER CYLINDRICAL MEMBER SECURED TO THE TOP AND EXTENDING INSIDE THE VESSEL FOR LESS THAN HALF THE LENGTH OF THE SAID VESSEL, A SHOWER PLATE SECURED TO THE WALLS OF THE VESSEL AND SPACED APART FROM THE TOP TO PROVIDE A WATER SPACE, MEANS FOR SUPPLYING WATER TO THE WATER SPACE, A FUNNEL-LIKE MEMBER SECURED INSIDE THE CYLINDRICAL VESSEL AND SPACED APART FROM THE ENDS OF THE SMALLER DIAMETER CYLINDRICAL MEMBER, SAID FUNNEL-LIKE MEMBER ALIGNED SUBSTANTIALLY AXIALLY WITH THE AXIS OF THE VESSEL AND BELOW THE BOTTOM OF THE SMALLER DIAMETER CYLINDRICAL MEMBER AND A FORAMINOUS COLLECTING MEMBER POSITIONED BELOW THE FUNNEL-LIKE MEMBER AND A WATER DISCHARGE AT ONE END OF THE CYLINDRICAL VESSEL AND BELOW THE FORAMINOUS COLLECTING MEMBER.

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