Process for preparing polyolefins by discontinuous addition of thermal runaway reducing agent
A thermal runaway and reducing agent technology, applied in chemical instruments and methods, chemical/physical processes, etc., can solve the problem that the overall productivity is not optimal
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
specific Embodiment
[0133] There are several different situations in which the addition of a TRRA may be required, each discussed in more detail below.
[0134] The so-called increase in skin temperature
[0135] In a first embodiment (Example A), the invention relates to a process for the continuous production of polyolefins from one or more alpha-olefin monomers in a reactor system comprising:* A reactor comprising at least a lower part, a middle part and an upper part, - wherein a distribution plate and an inlet for a recirculation flow below said distribution plate are located at the lower part of said reactor; - a fluidized bed, an inlet for polymerization catalyst, an outlet for polyolefin, a plurality of temperature sensing devices for measuring the temperature of the inner wall of said reactor are located in the central part of said reactor (middle of said reactor); and - an outlet for fluid is located at The upper part of the reactor, * a heat exchanger; * a first connecting means conne...
example
[0156] The effect of discontinuous addition of TRRA is demonstrated by the following non-limiting example. Titanium-containing Ziegler-Natta catalyst composition for the production of polypropylene homopolymer, said catalyst composition comprising diisobutyl phthalate as internal donor and methylcyclohexyl as external electron donor Dimethoxysilane (C-donor). A fluidized gas phase reactor is operated to produce polypropylene homopolymer with high static and skin activity. The polymerization rate was reduced to less than half the normal production rate of 22 TPH (tons per hour) to control skin activity and improve reactor stability. Ethyl p-ethoxybenzoate (PEEB) was then dosed into the reactor bed at a ratio to the catalyst feed rate, which was further controlled by monitoring catalyst activity and skin activity.
[0157] It is seen that with the gradual addition of PEEB, the catalyst activity decreases proportionally and also the skin activity indicated by hot spots starts t...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


