Several issues regarding the downstream applications of silicone

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I currently work at a small factory in the silicone downstream industry. Since this factory is about to launch a new project and has encountered several issues, I would like to discuss them with you all: 1. Can diaphragm pumps be used to transport carbon black? (Pigment black, with particle sizes of 20–50 microns, similar to silica gel); due to the low usage amount (approximately 200–300 kg/h), it is not convenient to use pneumatic conveying, and the investment required for such a system is relatively high. Therefore, the possibility of using diaphragm pumps for transportation is being explored. 2. Currently, most silicon oil dewaxing is carried out in reaction vessels; for applications requiring low levels of volatiles, the dewaxing process takes less time, while for those requiring higher standards, it takes more time, resulting in a longer duration overall. The book mentions the use of an internal circulation falling film distillation system, but both the investment and operating costs seem to be high. Is there any cheaper and more economical method? At the moment, I have considered two options: one is to use a low-molecular-weight removal unit (the kind used in raw rubber production lines), and the other is to use a scraper-type thin-film evaporator. Both of these should be feasible in theory, but they require some modifications. Do any of you sea friends have any other better methods? 3. A type of adhesive with a consistency of 5: Consistency is determined by placing the material on a flat surface and shaping it using a mold; then, a glass plate of a specified weight is placed on top of the material to apply uniform pressure in all directions. After 1 minute, the average outer diameter of the material under this pressure is measured, and this value represents the consistency. Based on my estimation, for materials with a viscosity of less than 5 million, their fluidity is too high, so their consistency is likely to be above 10. ), it comes out of the twin-screw extruder (with a diameter of around 80 mm), at a temperature of approximately 100–110°C; it needs to be cooled down to below 60°C. I thought of some solutions, but none of them worked well. We conducted an experiment in which the freshly extruded glue was directly immersed in water; after 5 minutes, it was taken out – its surface was cold, but its interior temperature was still above 100°C. I’m not sure if a shell-and-tube heat exchanger can be used? 4. It is said that pneumatic diaphragm pumps have relatively low energy consumption, but looking at the parameters of many such pumps, something seems off. Taking a case of 20 m3/h and H=50m as an example, the amount of compressed air required is approximately 1 m3/min. Are these figures based on standard conditions or actual operating conditions? Is there anyone who has used a pneumatic diaphragm pump and could explain it? Furthermore, there is a significant price difference between domestically produced diaphragm pumps and imported ones; domestic ones can be found for less than 2000, while imported ones cost 7000–8000. Is the difference really that great? What’s the problem with using domestic and imported ones?