A terrific example of a sustainable natural resource system is the Kraft papermaking process. Trees are harvested locally and taken to a paper mill. The bark and unusable wood are burned for energy recovery. Spent cooking chemical, called black liquor, is also burned for energy recovery. The sodium and sulfur chemicals come out of the bottom of the specialized boiler and are recycled and turned back into new cooking chemicals. When the mill is set up properly (from a sustainable perspective), boilers can run exclusively on locally grown fuels/raw materials to meet the mill's steam needs. Calcining is the only process that requires fossil fuels. However, I hear that some mills in Scandanavia use wood to calcine calcium carbonate.

It is an amazing system and I am surprised folks have not studied it to look for opportunities to inject more local inputs (i.e., using crops as a fuel) into agronomic systems.

Lawrence, thank you for taking the time to comment and share ideas that could be linked to those in this article.

Take a look at this article when you have time, you may find some good food for thoughts within it.

Respectfully yours;

Lucio