Ok, you need something to burn to start the process. This will later be replaced with the product, but to get started you need a fuel source.
We start by removing the water. Traditionally, this was done in a very inefficent manner, such that the total efficiency of removing the water took more energy than the product produced. Now, we use water to our advantage. Start by sealing the container, and heating it to ~400 F, and about 350psi. This breaks down the carbon strings a bit. Now, remove the pressure and you will remove most of the water - which we reclaim for heating the next batch.
This hot mixture (now minus the water content) is heated to about 600 F, under about 400 psi (much lower pressure/temp ratio, as the water is gone). Let sit for about 2 hours. This really breaks down the hydrocarbon stings. By the way, this is EXACTLY how we make gasoline and ligher petrolium oils.
In short, we have done in a matter of hours what mother nature takes millions of years to do. Pressure and temperature transform a forest into coal, dinosaurs into oil. We just sped the process up a few billion-fold.
Let's see, ignoring the cost of the heating equipment and the ASME pressure vessel, it would take roughly 106 BTUs of heat to heat up a ton of pig shit to 400F and an equal amount to heat up the pressure vessel. It would probably take another million or four to get it up to 600F and hold it there for long enough for the reaction to take place.
So just to heat up 2000# of the mess would cost from $50 to $125 in fuel costs alone. Fuel cost calculator
How much oil did you say a ton of pig shit would make?
(The above analysis ignores the labor costs of the thousands of pig shit shovelers.)