Precondition for inverting, mixing, and activating polymers
AssigneeNorthchem Industries
InventorDennis G. Pardikes
Life of this patent
Estimating the term…
Abstract
A process for activating polymer including preconditioning a diluent by heating it to a high temperature and then mixing the heated diluent with the polymer to form a blend having a high polymer content (e.g., about 5% polymer and 95% hot diluent). The blend is activated and then diluted by mixing it with a cold or cool diluent in order to provide an output stream of about 0.25-2% polymer having a relatively low temperature. The high temperature and high polymer content enables a continuous process, as distinguished from batch processes used heretofore which required substantial holding time in an aging tank. The reduction of the temperature of the blend by mixing it with cold or cool diluent prevents damage to heat-sensitive polymers.
Claims23
A polymer activation method comprising the steps of:
- preheating a diluent to an elevated temperature;
- carrying out a four-step activation process comprising the steps of (a) premixing a polymer and said preheated diluent, with said polymer having an elevated concentration of polymer to diluent, (b) blending the premix to a predetermined pressure in a derated centrifugal pump, (c) recycling a first portion of the blended mixture at said predetermined pressure, and (d) suddenly reducing said pressure to relax the polymer in a second portion of the blended mixture;
- diluting said relaxed mixture to produce both a temperature lower than said elevated temperature and a reduced concentration of polymer to diluent;
- and
- passing said relaxed and diluted mixture through a mixer to an output.
A system for activating polymer comprising:
- means for preheating a diluent to a high temperature;
- means for blending said heated diluent and a neat polymer in a pressurized loop, said blend having a high concentration of polymer to diluent;
- means for removing a portion of said blend from said pressurized loop;
- regulator means for subjecting said removed portion of said blend to a sudden and abrupt reduction of pressure;
- means for slowly conveying said blend from said regulator means through a reservoir, said speed of said slow conveyance and the size of said reservoir being chosen to retain said blend for a period of time being adequate to activate said polymer whereby said activation is a continuous process;
- means for diluting said blend issuing from said reservoir to reduce said high concentration of polymer to a useful concentration range;
- and
- means for mixing said diluted blend to produce a homogenous mixture of polymer to diluent.
A continuous process for activating polymer comprising the steps of heating a diluent to a relatively high temperature;
- blending neat polymer into said high temperature diluent at a concentration of about 5% polymer to 95% diluent, said blending occurring at a relative slow speed which completes said activation during a continuous process;
- diluting said blend to a concentration of about 0.25-2.0% polymer to 98-99.75% diluent;
- and
- mixing said diluted blend to produce a homogeneous outflow.
A process for continuously activating polymer, said process comprising:
- thermally preconditioning a diluent to a relatively high temperature of about 80°-180° F.;
- mixing said heated diluent with polymer to form a blend having a high content of neat polymer in the concentration of about 5% polymer and 95% diluent;
- activating said blend of polymer and diluent by a relatively slowly flowing stream during a period of time required to activate said polymer;
- diluting the activated blend to provide an output stream having polymer in the range of about 0.25-2% polymer;
- and
- operating a system continuously to process said polymer.
Dependencies are inferred from the claim text.