I'm not that familiar with the energy industry. I AM familiar with agri-business in America.
When I was in college a long, long time ago the Mississippi River downstream of a slaughter house would turn red when they discharged blood and guts during the day. No need for that.
I have a friend who is a manager in the "By-Products" division at a turkey processing plant and they use EVERYTHING including the beak, hehehe. They grind and dry the guts and use it as fertilizer. The make blood meal, bone meal, feather meal; they use everything! While they might not sell it at a profit and in fact they sell some of it for not much more than the freight costs, they save millions by avoiding disposal issues and costs.
Americans are innovators and they need to find a way to put their ash problem into a marketable product. Saves money in the long run and drives the tree kissers crazy when their issue goes away, hehehe.
“Pollution is a resource out of place.”
The reason for the use of the by products is that the beef industry cannot recycle parts of bovine back into the food chain for animals as other livestock. This is supposedly because of mad cow disease.
I remember growing up, my father would run my brother and I around to dead cattle skeletons and we would load up all of the bones. We would then sell the bones for bone meal. Great cash for my brother and I. The government eliminated this.