Pipe sampler

A pipe sampler is an off-the-belt sampler that collects increments from within the stream cross section by means of one or two pipes. The sampling pipes are mounted at an obtuse angle on a horizontal axle positioned at right angles to the direction in which the coal flows and increments are collected through an orifice that is located in the bottom wall of the sampling pipe. 

Air—electric samplers can be installed directly in the pipe wall. One type of Hquid sampler is operated by a solenoid valve that activates an air cylinder. A shaft is moved in and out of the pipe by this cylinder and samples are expeUed into a container below the sampler. Sample volumes of from 2—30 mL are possible. 

Fig. 13. Slurry samplers (a) sloping trough cutter and (b) vertical pipe cutter.

Sampling from pneumatic conveyors parallels gas sampling. The exception is that soflds loadings can be as high as 50 kg of soHds per kg of gas. Commercially available samplers extract particles directly from a transport line. Fixed position samplers are mounted directly on the pneumatic conveyor pipe. Devices are available which extract samples from the product stream by the projection of a sample tube iato the flow. Particles impact on the tube and fill the open cavity. The tube is then withdrawn, and an internal screw discharges the collected material (20). In another model, the RX Sampler (manufactured by Gustafson) (29), samples are withdrawn usiag compressed air. 

The method above, however, is not suitable when one needs a precise study of the vertical distribution of pesticides. Generally, the concentration of pesticides in paddy sediment is highest at the surface. Special care is required to avoid contamination with surface soil when the sediment is collected. The sediment core should be collected in two stages. First, a pipe with a diameter greater than that of the core sampler is inserted in the sediment and then water inside the pipe is removed gently with a syringe, pipet, etc. Next, a layer of surface soil (1-3 cm) is taken with a spatula or a trowel and then subsurface soil is collected with a core sampler to the desired depth see also Figure 4. 

Soil samples were collected along a traverse over the Honerat kimberlite and extended off the kimberlite approximately 75 m SE and 225 m NW from the pipe s centre (Fig. 1). Although it is common practice to collect samples from upper B-horizon soil (Levinson 1980 Bajc 1998 Mann et al. 2005) our samples were collected from C-horizon soil because GAGI samplers were placed at a depth of 60 cm (well below the B horizon). Within 8 hours of sampling, a portion of each soil sample was mixed with Milli-Q water (1 1) to create a slurry. The values of pH and oxidation-reduction potential (ORP) were determined in each slurry. Ammonia acetate leach of the soil samples were performed at Acme Analytical Laboratories, Vancouver, where 20 ml of ammonium acetate was mixed with 1 g soil sample and elements were determined by inductively coupled plasma-mass spectrometry. The GAGI samplers installed at Unknown were placed in piezometers and submerged in water at a depth of approximately 1 m below ground surface. 

Figure. 3.20 Colocation of correct upstream sampler and PAT sensor, shown here for a recirculation loop configuration (right). The PAT sensor is deployed in upstream small-diameter piping with a field of view matching as best possible the same stream segment which is being sampled for reference analysis. This setup allows for reliable multivariate calibration because of the colocated [X, f] modalities.

This configuration has still another potential bonus. For the upstream sampler, especially in the loop configuration, it is not advantageous to employ large-diameter piping. Indeed it is optimal to specifically use a narrow diameter. 

A spoon sampler consists of one or more pipes, arranged like the spokes of a wheel. Openings located at the tips collect the sample as the device is rotated through coal on a moving belt. This machine can be designed to collect very small primary increments, but the spoon pipes may overflow during increment collection and the sample may be of questionable reliability. 

Composite samples are typically collected for soil stockpile or surface area characterization. Twenty-four-hour composite samples of water may be collected with automated composite samplers from streams or process piping composite samples may be made of several grab samples collected from different depths in a soil boring. 

The Kemmerer sampler is a length of pipe with messenger-activated top and bottom stoppers. The liquid flows freely through the sampler, while it is being lowered to a desired depth on a measured line. Once this depth has been reached, a messenger is sent down the line to activate the top and bottom stopper closure. Because the Kemmerer sampler is typically made of brass, which is not an inert material, its use is limited. 

In practice, a decision on the representativeness of the water flow is often established based on the sampler s knowledge of the system piping. A change in water temperature, however, is the most obvious indicator of a stable flow as the sampler can sense it even with a gloved hand. A stable temperature reflects a stable water flow. 

The reactor is draft-loaded with corresponding amounts of butylbromide, tin and butyl alcohol. Then the apparatus is closed with a lid fashioned with an agitator, moved into the operation chamber and connected to all piping. After that the jacket of the reactor is filled with a heat carrier with a temperature of 90-95 °C, the contents of the apparatus are heated at agitation to 85-90 °C, the operation chamber is closed with a protective plug and sources of y-radiation are introduced into the chamber. After certain periods of time the mixture in the reactor is sampled with the help of a special sampler. 8-10 hours after the radiation has started, the reaction is completed and the sources of radiation are taken out of the chamber. The reactive mixture is loaded off and the apparatus is prepared for the next operation. 

Auger sampler A pipe with a slot is placed While this is often used for... 

Fig. 1.35 (a) Osborne s rotating slot slurry sampler, (b) Osborne s sampling tank, (c) Cross s slotted pipe slurry sampler... 

Osborne [25] described a sampler that consists of a narrow slot continuously rotated on an axis parallel to the slun7 flow (Figure 1.35a). Cross [26] used a slotted pipe mounted vertically in the overflow compartment next to the vortex finder of a hydrocyclone (Figure 1.35c). 

Due to their simplicity side-wall samplers are superficially attractive (Figure 1.37) but serious errors in concentration and particle size distribution can arise unless the particles are fine, the concentration is high and a very high sampling velocity is used. A projection extending from the pipe wall only marginally improves sampling efficiency [29]. 

Thin L-shaped probes are commonly used to measure solids concentration profile in slurry pipelines (28-33), However, serious sampling errors arise as a result of particle inertia. To illustrate the effect of particle inertia on the performance of L-shaped probes, consider the fiuid streamlines ahead (upstream) of a sampling probe located at the center of a pipe, as shown in Figure 2. The probe has zero thickness, and its axis coincides with that of the pipe. The fluid ahead of the sampler contains particles of different sizes and densities. Figure 2A shows the fluid streamlines for sampling with a velocity equal to the upstream local velocity (isokinetic sampling). Of course, the probe does not disturb the flow field ahead of the sampler, and consequently, sample solids concentration and composition equal those upstream of the probe. 

C solids concentration in the sampler, volume fraction Cb average solids concentration over the pipe cross section, volume fraction... 

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