Animal Fats for Biodiesel Production
Biodiesel is an essential fuel for transportation purposes as it ecologically maintains the quality of air and keeps the environment pollution-free. It is mainly produced from vegetable oils that have greater demand for edible consumption by humans. Such bilateral requirements have led to an increasing rate of vegetable oils over the years. To counter this problem using an alternative, industries have begun to adopt a low cost and much reliable approach for biodiesel production, which is through waste animal fats or by-products from processed meat.
Poultry bred animals like chicken, pork and beef are considered as a rich source of fat. When they are slaughtered for food, the residue fats that are inedible by humans are usually processed to manufacture glycerine, animal feed, pet food and soap. These residue materials are often exported for domestic or industrial usage. However, their contents can produce high-quality biodiesel that can be economically helpful to a nation like India.
Processing Animal Fat:
Chicken fat, beef tallow & pork lard along with other waste fats from animals are often processed into an oil. Initially, by-products from residue meat or processed meat are grind to fine consistency. Then they are cooked to destroy pathogens. Cooking is stopped once the liquid fat is separated & released from the meat. Solid meat is well-pressed using an equipment to obtain fat from the solid residue. Cooking also ensures removal of excess water from residue to avoid staling of fat or solids. This procedure is called a rendering process. Fat & bone meal (or meat meal) are the two end products obtained from the rendering process. Bone meal can be further used as a fertilizer or a feed supplement due to its high-protein value.
Feedstocks from Animal Fats:
- Fatty Acids
Animal fats have high moisture value. This highly saturated nature enables them to solidify at a very high temperature. This is the reason why biodiesel made out of animal fat has a high cloud point (a temperature at which fuel observes slight crystallization as it cools). For example, biodiesel made from pork lard or beef tallow has a cloud point between the range 55oF to 60oF. This is because pork lard & beef tallow are around 40% saturated, whereas chicken fat is around 33% saturated. This is why tallow suppliers in India are popular in biodiesel production for warm climatic areas of the country.
- Oxidative Stability of Produced Biodiesel
Oxidative stability of biodiesel is dependent on the saturated fatty acids in animal fats. If more, they can ensure the fuel a better oxidative stability, keeping it from rancidity for a longer time. However, if the fat contains a high amount of polyunsaturated fatty acids like as linoleic acid and linolenic acid, it can be prone to early rancidity than usual.
- High Cetane Number
Cetane number is a crucial parameter to determine quality of diesel fuels. Again, this parameter is dependent on the saturated fatty acids present in animal fats. If you are into biodiesel production, ensure that the rendering processed animal feedstocks contain a high cetane number. You can evaluate animal fats suppliers in India for cetane number before production to maintain fuel quality.