MXPA00008031A - Fiber sampling device - Google Patents

Abstract

A device for obtaining a sample of fiber from an aqueous slurry of fiber flowing through a stock line (8), comprising a first isolation inlet valve element (5) together with a water supply orifice, located inside a fiber stock line;a second isolation valve means (4), and a third isolation valve (7), mounted in flow series from the sample inlet point on the stock line. This device allows a complete water purging down through the inlet valve element, as well as fiber samples to flow out of the stock line in the presence of diluent water. Samples flow from the first isolation valve means to a final collection point, without contamination or plugging.

Description

FIBER SAMPLING DEVICE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved device for obtaining a fiber sample from a fiber processing silver, such as a paper or pulp mill, a corn silver, or a starch plant. The improved fiber sampling device has several advantages over ordinary sampling devices, including the ability to completely discharge, in order to remove the residual fiber, and the ability to be installed and removed while the plant is in operation. The improved fiber sampling device, therefore, allows fiber processing plants to obtain useful samples more easily and with less contamination than with ordinary sampling units. 2. Brief Description of the Prior Art A large number of industries are based on the processing of natural fiber. The pulp and paper industry, for example, convert wood fiber to pulp and paper products. The corn processing industry converts corn to starch, sugar, corn oil, and other products. Other crops, such as wheat and soybeans, are processed in an analogous manner. The cotton fiber is processed to make fabrics and other textile articles. A need that this wide range of industries have in common is the need for fiber sampling. All fiber processes are run at specific conditions (temperature, pH, salt concentration, etc.), and run to give a given degree of processing (chemical reaction, purity, removal of inhibitors, etc.). Although a good array of automated instrumentation is available to monitor and control these process variables, in almost all plants there are some process variables that are not automatically controlled, and fiber samples are required to control the process. In addition, most automated controls require occasional (or frequent) calibration with current samples. Much of the sampling of the fiber is carried out manually. Manual fiber sampling consists of grabbing a sample of fiber with one hand or with a spoon, where the fiber is exposed openly. If the fiber is flowing into a line of diluted wood pulp, a manual sample can be taken by opening a valve attached to the line and using the pressure in the line to forcibly remove the sample. The sample is collected until the desired amount is obtained, and then the valve is closed. A more sophisticated form of manual sampling consists of two valves in series, connected by an intermediate tube that is 6 to 12 inches long. The valve closest to the line of the diluted wood pulp, referred to later as the first isolation valve, opens and closes to take a sample, the valve farthest from the line of diluted wood pulp, referred to later as the second valve The insulation is closed except when removing a sample from the tube. To take a sample, the first valve opens to fill the intermediate tube with fiber. The first valve is then closed, and the second valve is opened to allow the removal of the fiber sample.

An advantageous variant of the two valves in series is additional to a third valve to the system, which is joined to a T which is derived from the intermediate tube. This third valve can be opened to allow water in the intermediate tube, and remove the fiber sample when the second isolation valve is opened. This known three-valve sampler can be installed in line, that is, while the plant is running and the fiber is flowing through the pulp line of the line under pressure. This is advantageous, since it avoids the need to stop the mill to install the sampler. The online installation is carried out using a so-called hot drilling process. A first valve is connected to one end of a pipe nipple, the other end of the nipple is then soldered to a line of diluted wood pulp. A hot drilling apparatus is attached to the other part of the first valve. The valve opens; a drill bit is pushed through the opening into the valve body; until it is drilled through the wall of the diluted wood pulp line. The drill bit is then removed through the valve body and the first valve is closed. A first valve attached in this way to the diluted wood pulp line is then ready to be attached to an intermediate tube and a second valve. There are several disadvantages associated with the known three-valve systems. "First, there is no discharge of water between the first valve and the wood pulp line of diluted, and the fiber can accumulate at this point, and contaminate the subsequent samples. there is no technique to remove the entire system online, for cleaning or maintenance, while the operation of the known utes in three valves can be automated, to allow samples to be taken automatically, this automation does not exceed inherent disadvantages of the unit during automatic sampling For frequent or multiple samples, and for situations where a sample must be moved over a large distance for analysis, certain automated sampling units are known. listed in Table 1. These devices are used for specific consistencies of solids, tube diameters, process temperatures, and construction materials. In each device, a sample is transported to a desired location or instrument at either: 1. Internal pressure in the diluted wood pulp line, which feeds the sample directly to the instrument at a short distance. 2. A piston-type pressure, where a moving piston carries a fiber sample at a distance of 50-200 feet. 3. A type of fluid, where the water transports the sample to the instrument. A typical example of these devices is the Kajaani SD-503, which contains a sampling valve element that is inserted into the diluted wood pulp line, and electrically operated from outside the line of diluted wood pulp. The pulp of the sampling valve is a plunger that opens and closes to admit a sample. This sampling valve is short (with a length less than 2 inches), and has an inlet hole coupled to the wood pulp line diluted by a process coupling. The outlet part of the sampling valve is attached to a sample chamber. The pulp samples pass through a sample chamber and out of a hose, to a remote location. The water is admitted to the sampling chamber, at a point just below the process coupling. This water is used to transport the samples out of the sample chamber, and into the hose. A disadvantage of the device of the sample SD-503 is the inability for the complete discharge of water from the sample chamber. The system is not designed to discharge water, which penetrates the sampling valve element anyway. In addition, slits within the sample chamber trap and retain the fiber. This makes an accumulation of fiber in or near the isolation valve probably, which causes cross-contamination of the samples. Another disadvantage of the SD-503 sampling device is that it can not be installed or removed online. The requirement to stop the plant or fiber line before installing or removing the sampling valve element is a serious drawback, and a cost factor.

TABLE 1 AUTOMATIC SAMPLING DEVICES Therefore, despite the availability of a wide variety of fiber converters, there are significant drawbacks of these known devices. These drawbacks are addressed by the present invention.

BRIEF DESCRIPTION OF THE INVENTION The inventor has developed a device to automatically sample the fibers that can be unloaded completely to avoid the accumulation of fibers, and that can also be installed and removed online. The invention allows operators of fiber processing plants to obtain samples more conveniently and without cross-contamination of previous samples. Therefore, the present invention results in samples of better quality, with less effort and less maintenance. A unique aspect of the fiber sampler has taught herein that it is a first isolation valve and sample chamber with a water discharge configuration that allows the water to be completely discharged, thereby eliminating cross-contamination of the fiber samples. . In a preferred embodiment, the valve member of the fiber sampler can be inserted through a valve and into a line of diluted wood pulp for in-line installation and removal.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated in a preferred embodiment with reference to the accompanying drawing in which: Figure 1 is a vertical, schematic elevation view of a preferred embodiment of an automated sampling device according to the present invention.

DETAILED DESCRIPTION PEE A PREFERRED MODALITY Figure 1 illustrates a preferred embodiment in use, where an automated sampling device has been mounted on a fiber pulp line. The device essentially comprises a valve element 5 of the fiber sampler located within the pulp line, and controlled by a linear actuator 1. The valve 5 is the first isolation means, or the primary insulation means that controls the fiber flow in and out of the sampler. The actuator 1 is a pneumatic solenoid acting linearly on the first valve element 5 of the sampler through a hollow tube 5, in order to open and close the valve element 5 against a conical or spherical seat, in the form of a valve with valve lift. A second isolation valve, or secondary valve, in this mode is preferably a ball valve 4, through which a complete, tubular, sample chamber 3 can be inserted. Valve 4 opens unless the sampler is being removed. This embodiment also includes a third remote or tertiary isolation valve 7, as well as the liquid inlet orifices 2 and 6, to regulate the flow of water in the system. The liquid orifice 2 is connected to a main line of high pressure water, by a conventional valve (not shown). A sampling cycle can start with an initial fiber purge, where the valve 7 closes and the actuator 1 opens the valve element 5 of the sampler. The water or other cleaning liquid can be forced through the inlet holes 16, to flow respectively outwardly and inwardly of the hollow tube 9, downstream of the sampler valve element 5 and into the line 8 pulp. This discharge configuration passes water through the sample chamber, complete, both inside and outside the actuator tube 9, into the tubular chamber 3. The geometry of the chamber and the tube illustrated in Figure 1 is defined by smooth surfaces and clear, to eliminate any sharp crack where the fibers will accumulate. For this, or other type of discharge actions, as described below, there is a purge that completely removes the residual fiber from the sampled device, thus preventing contamination of subsequent samples. With an initial full fiber purge, the actuator 1 is adjusted to allow the valve element 5 of the sampler to open; the third valve of the element 7 opens; and the water source in the inlet port 2 of the liquid is closed, to depressurize the sampler completely. The internal pressure within the pulp line 8 forces the pulp fiber through the valve member 5 and into the tubular sample chamber 3, and specifically towards a fluid ring outside the actuator tube 9. The fiber sample then It is transported up to the tube 3 towards the third isolation valve 7. When sufficient sample of fiber is collected, the actuator 1 closes the first valve element 5, and high pressure water from a main water line, is admitted in the inlet hole 2 of the liquid. The sample is then transported downstream beyond the third valve 7, by flowing water from the inlet port 2. An inverted, or re-discharging, type of the initial purge may not always be necessary. When sufficient fiber has been collected, the diluent water from the inlet port 6 can be forced simultaneously so that the tube 9 flows down to the closed valve element 5, and then back to the outer ring of the tube 9. This action will then act as a second important purge in order to remove the lost fiber from the sample chamber. When a sample reaches its destination, and both the valve 5 and the third isolation valve are closed, then the water pressure inside the sample chamber 3 can be allowed to rise above the internal pressure in the pulp line 8, and it is a provision for another initial purge. A cycle of valves 1 to 7 to thereby adjust the pressure within the sample chamber 3 can be controlled in a conventional manner by an external timer circuit or computer (not shown) in a conventional manner. A sample of pulp is first diluted with water, at or near the sample valve element 5. The diluent water can be added through the inlet port 2, from a high pressure main water line, while a sample is being taken from the pulp line. In a more preferred embodiment, as illustrated in Figure 1, the pulp is diluted with water entering the inlet port 6 from a low pressure water line, with the diluent water traveling in and down the actuator tube 9 , and it is admitted to the pulp sample at or near the valve element 5. A typical dilution (expressed as pulp weight) is approximately 10: 1, but this relationship can be varied widely by pressing the dilution water source or varying the dilution water pressure relative to the pulp pressure. This controlled dilution in the sample valve element advantageously allows the sampling of the thicker suspensions with higher fiber consistency. Existing automatic sampling devices that use water to transport a sample of fiber so as not to dilute the sample at the initial point of sampling, but rather in an instrument or other remote location. This remote dilution increases the possibility of plugging the sample line near the pulp line. The installation of a secondary isolation valve 4 can be carried out in line where a hot drilling procedure, as described above. Once the ball-type valve element inside the valve 4 is opened, a distal end of the tubular chamber 3 and the tube 9 (with the valve element 5) are inserted downstream through it, and the proximal end is inserted. of the tube is connected directly to a linear actuator connector in the solenoid actuator 1. The sampling unit is then operated with the ball valve 4 always open. The sampler assembly moves from the pulp line, for cleaning or maintenance, by lifting the distal end of the tubular chamber 3 and tube 9 up through the secondary isolation valve 4, and then closing this valve. Then, the upper assembly of the threaded nipple connection shown just below the valve 4 is removed. This does not interrupt the flow or pressure in the pulp line. For better operation, the cylindrical opening in the ball valve element of the secondary element valve 4 maintains a leak tight seal against the outside of the tubular sample chamber 3. This arrangement self-centers and self-corrects for any wear or damage due to sand within the fiber line. In essence, the tubular sample chamber 3 is designed to allow the water to discharge to completely remove the fiber from inside that chamber. This is achieved by allowing the water to discharge an unimpeded flow out of the chamber, and placing the flow such that it is unidirectional and does not interfere with twisting, turns, stagnation zones, or other configurations that trap or retain the fiber or give incomplete fiber removal result. In the embodiment illustrated by Figure 1, the sample chamber consists of the ring between the cylindrical tubes, concentric, with the tube 9, an inner cylinder in the chamber 3 or an outer cylinder. The discharge of water is carried out by flowing the water out into the tube 9 as well as the ring outside the tube 9. There is no other space within the sample chamber for the fiber to accumulate. It will be recognized by those skilled in the art that several alternative designs are possible, including but not limited to the inner circuit located outside the center to the outer cylinder, or the presence of more than one inner cylinder, or non-cylindrical conduits. In the preferred embodiment, the fiber sample flows in the brick between the coaxial cylinders. It will be recognized by those skilled in the art that several alternative designs are possible, including the fiber flowing inside the inner cylinder. In the preferred embodiment of Figure 1 the entire sample chamber is slidably inserted into a cylindrical passage in a ball valve element. This allows the valve to be installed or removed in line. The minimum length of this chamber proves to insert through a valve and protrude into the pulp line is about 4 inches. A preferred length is approximately 8 to 18 inches. Sample chambers longer than this length are difficult to discharge completely. The practical size, maximum of chamber 3 at the point passing through ball valve 4 is an outer diameter of approximately 0.5 inches. If the diameter is larger than this, the force required for the manual removal installation the device, which must overcome the pressure force of the pulp line, is too large. An outer, most preferred diameter of the sample chamber is less than about 0.75 inches. The primary isolation valve means may in practice be any means for isolating the fiber sample from the pulp line and opening and closing to allow samples. Various familiar modalities for those skilled in the art are conical seat valves, flanges, diaphragms, and couplings. The primary isolation valve means may be actuated by a pneumatic actuator, an electrical actuator, or other device familiar to those skilled in the art. The actuator is located outside the fiber source, in contrast to the valve 5, which is located within the fiber source. In the preferred embodiment shown in Figure 1, the valve member 5 is operated pneumatically. In the preferred embodiment, the actuator 1 is a pneumatic solenoid. The secondary isolation valve means can be any valve or device-similar to those familiar in the art, which allows the passage of a stop 3 from a valve opening. Some examples of these ball valves, gate valves, butterfly valves, and diaphragm valves. In a preferred embodiment, a ball valve is used, wherein the valve opening is straight to allow insertion of a main sampler tube. In a preferred embodiment, the valve also has threaded inlet and outlet holes. In a more preferred embodiment shown in Figure 1, the valve 4 is a threaded ball valve. The tertiary isolation valve means can be any valve or similar device familiar to those skilled in the art, which allows the passage of a thick fiber suspension when opened, including a ball valve, gate valve, diaphragm valve, valve of butterfly, or other valve device. In a preferred embodiment shown in Figure 1, a sanitary diaphragm valve is used to allow for rapid opening and closing. The transport water inlet medium, connected to high pressure water, can employ any valve or similar device familiar to those skilled in the art, which is used to control the flow of water. In a preferred embodiment, the liquid inlet orifice 2 includes a near solenoid valve. In a more preferred embodiment, shown in Figure 1, a proximal, valve inlet 2 is a solenoid diaphragm valve. The diluent water inlet medium, connected to a smaller water line, can employ any valve or similar device familiar to those skilled in the art, which is used to control the flow of water. In a preferred embodiment, the liquid inlet orifice 6 includes a nearby solenoid valve. In a more preferred embodiment, shown in Figure 1, a proximal valve inlet 6 is an electric solenoid diaphragm valve. The parts of the fiber sampler can be manufactured using stainless steel, other metals or plastics compatible with the chemicals present in the materials being sampled. In a preferred embodiment, the fiber sampler body is made using titanium. While the embodiment illustrated in Figure 1 shows the sampler mounted to a fiber source which is a fiber pulp line, any pressurized containment, such as an overflow tank, is equivalent to the illustrated section of the pulp line . In practice, the sampler can be mounted to any containment of thick, aqueous slurry that is at least 0.5 psi under pressure, to pass the sample in the sampler unit. These containments include but are not limited to containment tanks, spill tanks, and pulp lines.

While a preferred embodiment has been shown and described, the invention will be defined solely by the scope of the appended claims.

Claims (9)

1. CLAIMS 1. A device for obtaining a fiber sample from an aqueous slurry of fiber within a pressurized containment, which comprises in combination and mounted in series of flow from an entry point in the containment: a first medium of isolation valve close to the entry point of the containment; a sample chamber; a second means of isolation valve; a means of introducing water, whereby a sample flowing out of the pulp line can be mixed with water before or in the sample chamber; and a third means of isolation valve. The device according to claim 2, wherein the pressurized containment is a pulp line; the first isolation valve means further comprises a linear, remote actuator that is presented to a first valve member that is within the pulp line, the connection further comprising an actuator tube having a proximal end that is connected to the actuator remote linear and a distal end supporting the first valve element, wherein the actuator tube extends through the second isolation valve means. 3. The device according to claim 2, wherein the water distribution means further comprises a diluent water source which is selectively distributed to a sample, at a point proximate to the first valve member, by the actuator tube located within the the sample chamber, the outer portion of the sample chamber which is tubular and which slidably fits through an open ball valve element, which comprises the second isolation valve means. 4. The device according to the claim 3, wherein the outer diameter of the tubular sample chamber is less than 1.5 inches. The device according to claim 1, wherein at least one water introducing means further comprises the sample chamber connected to at least one purge water source which is capable of maintaining the discharge of the fiber sample in the chamber of sample either beyond the first isolation valve element and in the containment, or beyond the third valve means. The device according to claim 5, wherein the source of purge water is introduced into one end of the sample chamber and is close to the third isolation valve, and the inverted discharge is carried out in a sample chamber which is defined between the outside of an actuator tube and the inside of a surrounding cylindrical tube. 7. The device according to the claim 5, wherein the fiber sample enters the outer portion of the sample chamber defined between the outside of an actuator tube and the inside of a surrounding cylindrical tube. 8. The device according to the claim 5, wherein at least the water introduction means further comprises a source of diluting water and is transported through the interior portion of the sample chamber to an orifice that is proximate to the first isolation valve means. 9. The device according to the claim 6, wherein the driving tube and the surrounding cylindrical tube are substantially concentric, and the pulp fiber is transported in a ring defined between the actuator tube and the valve tube. The device according to claim 5, wherein the source of purge water is introduced into one end of the sample chamber and is close to the third isolation valve, and the inverted discharge is carried out in a sample chamber which is defined 'between the outside of an actuator tube and the inside of a surrounding cylindrical tube. 7. The device according to the claim 5, wherein the fiber sample enters the outer portion of the sample chamber defined between the outside of an actuator tube and the inside of a surrounding cylindrical tube. 8. The device according to the claim 5, wherein at least the water introduction means further comprises a source of diluting water and is transported through the inner portion of the sample chamber to an orifice that is proximate to the first isolation valve means. 9. The device according to the claim 6, wherein the driving tube and the surrounding cylindrical tube are substantially concentric, and the pulp fiber is transported in a ring defined between the driving tube and the tube