| Author | Message | ||
     Michael C Mound (mike) Senior Member Username: mike Post Number: 45 Registered: 7-2007 |
...by the way, my e-mail is [email protected]... | ||
| Michael C Mound (mike) Senior Member Username: mike Post Number: 44 Registered: 7-2007 |
Hello, Gabi, This is an oldie, I know, but I happened across it just today as I was checking slurry news, myself. If you have some details as per that which you (I assume) sent on to Jim, that would be appreciated, if you can dig them out. My own interest is characterization of ca. 30% solids in a pipe-type conduit. I can arrange to insert in-line probes, I imagine, and, since these are mostly medium mineralogical hydrophobic finely divided inorganic particles (silt-sized) and there are multiple points, I imaging that diffuse reflectance would be best. There is enough turbulence, or, if not, I could insert a turbulence-inducer such as a high-density plastic baffle series to vortex the flow and avoid window/flowcell deposition. Thanks to all, Mike | ||
| Jim Bob |
has anyone had any expierience using nIR to determine the concentrations of slurries? if so can anyone offer advise on the best way of doing this? | ||
| W. Fred McClure (Mcclure) |
Jim, If you will send me your Email address I'll send you a diagram of a sample holder I built for slurries. Fred [email protected] | ||
| Jim Bob |
Fred, you can send any information to [email protected] anything you can tell me will be greatly appreciated. Cheers, Jim | ||
| Gabi Levin |
Hi Jim, Slurries - almost anything can get into this definition - from low concnetration of solids, to dough. My questions are: 1. What do you wish to measure in the slurry - i) suspended solid concnetrations? ii)Concentrations of dissolved chemicals in the liquid phase of the slurry? iii) Concentrations of different chemicals suspended as solids in the slurry? 2. Where do you wish to measure? in the process or in the lab? 3. If in the process, is the slurry flowing in a pipe, is it being agitated in a vessel? 4. Do you have multiple points to measure in, or is it a single point that you need to measure? 5. If in the lab - is the liquid very volatile? If it is, pulling a sample into open air is a problem, so you need a smapling device that will pull the sample into a closed container, and possibly the container itself will be used to collect signal in diffuse reflecatnce through one of it's walls. If it is not volatile, you can pull a sample into a small dish and simply present it to a diffuse reflectance spectrometer set-up. 6. One major issue in the lab - do the particles in the slurry stay nicely suspended over several minutes at least, so collecting signal in diffuse reflectance does not depend on where in the sample you collect the spectrum from? If they settle quickly it becomes an issue of how to keep them evenly dispersed during the measurement. Based on such answers I could recommend different approaches. In general, slurries (unless containing high level of activated carbon, or graphite or too low concnetration of particles) will be very good diffuse reflecting media. If the concentration of suspended soilds is low enough, you could possibly use a probe which combines diffuse reflectance and transflectance signal for better representation of the mixture. If you can not get light through ~0.5mm of path length, you would probbaly be better off with diffuse reflectance. If you use diffuse reflectance, then if it is in line, and it is a single point, you can use instruments that illuminate and collect through a window that can be mounted in the pipe, or in the wall of a vessel (assuming the slurry does not build up deposits on the window) If it is a multiple point - you can use diffuse reflectance probes, with multi fibers, and use a spectrometer that can be multiplexed for several channels. Probes can be either inserted into a vessel or into a pipe, methods of installation may vary from company to company, or they can be integrated with a flow cell. If the slurry builds deposits on surfaces, you may need to go with a retractable probe so you can pull it out every once in a while, as experience will dictate, for cleaning puproses without having to stop the process, etc. More detailed answers with specific models I can provide outside the scope of this forum if you write to me. Gabi Levin Brimrose | ||
| jim bob |
the surry consists of a drug in ethanol and water. I wish to detect the solution and the soid particles. The purpose is to monitor the concentrations of the 3 components during distillation and will initially be carried out in the lab with an aim to run it on the plant process. |