Linear Programming Example

A refinery must produce 100 gallons of gasoline and 160 gallons of diesel to meet customer demands. The refinery would like to minimize the cost of crude and two crude options exist. The less expensive crude costs $80 USD per barrel while a more expensive crude costs $95 USD per barrel. Each barrel of the less expensive crude produces 10 gallons of gasoline and 20 gallons of diesel. Each barrel of the more expensive crude produces 15 gallons of both gasoline and diesel. Find the number of barrels of each crude that will minimize the refinery cost while satisfying the customer demands.

Refinery Optimization with Linear Programming

Refinery Optimization with Mixed Integer Linear Programming

Soft Drink Production Problem (Example 2)

A simple production planning problem is given by the use of two ingredients A and B that produce products 1 and 2. In this case, it requires:

  • 3 units of A and 6 units of B to produce Product 1
  • 8 units of A and 4 units of B to produce Product 2

There are at most 5 units of Product 1 and 4 units of Product 2. Product 1 can be sold for 100 and Product 2 can be sold for 125. The objective is to maximize the profit for this production problem.

A contour plot can be used to explore the optimal solution. In this case, the black lines indicate the upper and lower bounds on the production of 1 and 2. In this case, the production of 1 must be greater than 0 but less than 5. The production of 2 must be greater than 0 but less than 4.

Soft Drink Production Problem

Solve the Production Problem Online

Modified Production Problem

Solve the Modified Production Problem Online

Solution and Contour Plots with Python

Below are the source files for generating the contour plots in Python. The linear program is solved with the APM model through a web-service while the contour plot is generated with the Python package Matplotlib.

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