BY-PRODUCT

A by-product is a secondary or incidental product deriving from a manufacturing process or chemical reaction, and is not the primary product or service being produced. A by-product can be useful and marketable, or it can have severe ecological consequences.

Major by-products

• asphalt - from the refining of crude oil
• sawdust and bark- from the processing of logs into lumber
• corn stover - residual plant matter after harvesting of cereals
• bran and germ - from the milling of whole grains into refined grains
• meat and bone meal - from the rendering of animal bones and offal
• orange oil and other citrus oils - recovered from the peels of processed fruit
• pectin - recovered from the remains of processed fruit
• glycerol - from the production of biodiesel
• lanolin - from the cleaning of wool
• collagen and gelatin - from the boiled skin and other parts of slaughtered livestock
• slag - from ore refining
• feathers - from poultry processing
• chrome shavings - from a stage of leather manufacture
• whey - from cheese manufacturing
• acidulated soap stock - from the refining of edible oil
• molasses - from sugar refining
• dried blood and blood meal - from slaughterhouse operations
• brewer's yeast - from ethanol fermentation
• distiller's grains - from ethanol fermentation
• manure - from animal husbandry
• poultry litter - swept from the floors of chicken coops
• gypsum - from Flue gas desulfurization
• ash and smoke - from the combustion of fuel
• straw- from grain harvesting
• grape seed oil - recovered from leftovers of the winemaking process
• sludge - from wastewater treatment
• mineral oil - from refining crude oil to produce gasoline

See also

• By-product synergy