Chemical apparatus and process disinfecting – deodorizing – preser – Control element responsive to a sensed operating condition
Patent
1986-03-17
1988-04-05
Smith, Edward J.
Chemical apparatus and process disinfecting, deodorizing, preser
Control element responsive to a sensed operating condition
526 59, 422 62, 422108, 422131, 436 85, G01N 3344, G01N 3096, G05D 2300, L08F 200
Patent
active
047357797
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to a method for testing the viscosity of synthetic resins during the manufacturing process of these synthetic resins in a reactor, with a slight partial flow of synthetic resin being withdrawn from the reactor.
STATE OF THE ART
The viscosity must be constantly monitored as a determinant parameter during the manufacture of synthetic resins. Presently the conventional procedure is to sample the reactor. Such samples then are examined in the lab and the test results determine the further process. Sampling and viscosity determination in the lab as a rule demand from a quarter to three-quarters of an hour. Because the viscosity rises especially ever more rapidly toward the end of the process, the delivery specifications can be exceeded on account of the time required to test the viscosity.
Another problem is incurred, namely that there is no clear relation between the viscosity of the flowing melt, ie of the product in the reactor, and that of the resin which corresponds to the delivery specifications, ie the final synthetic resin. This is the case especially where a solvent is added to the synthetic resin. This is a minor problem so long as macromolecular materials put together from sharply defined chemical raw substances, are involved. Illustratively this is the case for the manufacture of unsaturated polyesters. If on the other hand raw materials such as oils and fats are used in the manufacture of synthetic resins products, substantial problems are incurred. Almost in all cases there is absent an unambiguous relation between the viscosity of the flowing melt and the solvent viscosity, ie the viscosity of the end product. Also, even slight deviations in solvent composition may cause further deviations in the end product.
It is known per se furthermore that the solid content in synthetic solutions normally is between 50 and 70%. Accordingly when the viscosity is tested in the lab following sampling, dilution takes place in the same ratios, and the viscosity is then determined at a fixed temperature. The serial sampling is continued until the desired end specification is obtained. Thereupon the reactor process is interrupted, most of the time by cooling. Because of the repeated withdrawals of samples each requiring its own viscosity determination, it happens,--it can hardly be avoided, that the last point in the process is not reached or is exceeded, whereby deviations are incurred in the viscosity from that desired in the end product.
DESCRIPTION OF THE INVENTION
Beginning with the method initially discussed, whereby a small partial flow is withdrawn from the reactor and from which then samples are taken in the manner described and are tested, it is the object of the invention to create a method for viscosity testing allowing to determine the viscosity of the synthetic resin in the reactor at any time and without loss of time, and whereby furthermore an unambiquous relation may be established to the viscosity of the end product.
This object is solved by the invention in that the partial flow is tapped continuously and then is cooled to a constant temperature and is continuously fed thereupon to an in-line viscosimeter.
A preferred implementation of the method consists in feeding continuously a solvent at such a specified ratio to the partial flow in which it is then mixed that a match is obtained with respect to the end product, and in that thereupon cooling is undertaken.
Further advantageous implementations of the method of the invention are stated in the dependent claims 2 and 4 through 7.
The invention furthermore concerns apparatus to carry out the above discussed methods, with a reactor (reaction vessel) and with a tap line for a small partial flow of the synthetic-resin reactor contents and with a feed pump in the tap line, being characterized in that the tap line is provided with a heat exchanger acting as a cooler and in that as seen in the direction of flow, an in-line viscosimeter (viscosity tester) in present after the heat exchanger.
Further advantageo
REFERENCES:
patent: 2989517 (1920-06-01), Hanson et al.
patent: 3108094 (1963-10-01), Morgan
patent: 3493345 (1970-02-01), Windley
patent: 3503937 (1970-03-01), Allen et al.
patent: 3787359 (1974-01-01), Horn et al.
Mulcahy Peter D.
Smith Edward J.
LandOfFree
Method for testing the viscosity of synthetic resins and apparat does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for testing the viscosity of synthetic resins and apparat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for testing the viscosity of synthetic resins and apparat will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2232495