Issues related to processes and equipment for ring-type polypropylene production
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1. Our unit is designed as a loop reactor with a capacity of 300,000 tons; the intended production rate should be 37.5 tons per hour, but it is currently 45.5 tons per hour. After one month of operation, it was observed that the power consumption of the first loop axis fluctuates significantly, while the vibration levels in the second loop are high. The density is around 560.2. As the load increases, the low-pressure recovery value of PK301 does not increase accordingly.
3. Recently, we have been using propylene produced by our own PDH unit; the levels of isopropanol in this propylene are 6 ppm, and those of methanol are 3 ppm. The amount of donor used is now three times higher than before; it’s not clear whether this is related to the issues we’re facing.
4. Previously, the methanol level was 70 ppm, which caused the buffer tanks related to PK301 to experience frequent overpressure conditions. There was liquid accumulation in these tanks, similar to light hydrocarbons, and the gas valves were covered with sticky, gel-like substances that were flammable
If the shaft power is high, consider whether there is excessive non-condensable gas; exhaust from the top of the ring pipe can be tried. The amount of DONOR added should not be too high; a certain aluminum-to-silicon ratio must be maintained, otherwise the ash content will be too high, placing a heavy burden on the back-end system