US 2014/0178610 A1 · TRANSFER LINE EXCHANGER

Abstract

The present invention provides a transfer line exchanger which is optimized for one or more objective functions of interest such as pressure drop, erosion rate, fouling, coke deposition and operating costs. The transfer line exchanger is designed by computer modeling a transfer line exchanger in which the cross section of flow path is substantially circular and modeling the operation of the transfer line under industrial conditions to validate the model design and its operation. Then iteratively the model design is deformed and the operation of the deformed part is modeled and compared to values obtained with other deformed models until the value of the objective function is optimized (e.g. at an extreme) or the change in the objective function is approaching zero.

Claims14

Dependent claims

A transfer line from an olefins cracking furnace to a quench exchanger said transfer line having an internal flow passage having a continuously smooth and differentiable perimeter and centerline and a smoothly varying cross-section along the flow passage such that in the about 5% of the flow passage from the inlet and the outlet the ARQ is from about 1.0 to about 1.02 and over the remaining about 90% of the length of the flow passage not less than about 5% of the flow passage has an ARQ from about 1.02 to about 1.15.

A method to optimize one or more of the operating characteristics selected from pressure drop, erosion rate, fouling rate, and cost of a fixed industrial flow path defined by a continuous metal and/or ceramic envelope, comprising:

1. building a computational model comprising not less than about 5,000, computational cells of the portion of the flow channel from about 5% of the length of the flow channel downstream of the inlet to from about 5% of the length of the flow channel upstream of the outlet of the initial design of said industrial flow path;
2. using computer software that solves the fundamental laws of fluid and energy dynamics for each cell simulating and summing the results the operation of the model design from step 1 under the industrial pressure, temperature, and flow rate conditions of operation to verify one or more objective functions of interest;
3. iteratively
a) deforming said computational model comprising not less than about 5,000 computational cells so that the resulting ARQ of one or more sections of the flow path is greater than about 1.02;
b) applying the same computer software as in step 2, that solves the fundamental laws of fluid and energy dynamics for each cell simulating and summing the results of the operation of the deformed model from step 3a) under the industrial pressure, temperature, and flow rate conditions of operation used in step 2 to predict one or more objective functions of interest for the operation of the deformed model;
c) storing the predicted results from step 3b);
d) using some or all of the stored results from step 3c) with an optimization algorithm to estimate a deformation that will improve the objective function;
e) repeating steps a), b), c), and d) until one or both of the following conditions are met:
i) the objective function of interest goes through a beneficial local extrema;
or
ii) the rate of change of all of the all the functions of interest starts to approach 0.

8 more elements

Dependencies are inferred from the claim text.

Transfer line exchanger

Life of this patent

Transfer line exchanger

Life of this patent

Abstract

Claims14