Turning used cooking oil into biofuels
Via Processing Talk: Rising to the challenge of meeting the demand for new eco-friendly fuels, one Spanish company, Bionor, has managed to turn used cooking oil, a potentially hazardous waste product, into biodiesel.
“If not collected, the used oil is generally thrown down drains” says Alfonso Ausin, president and CEO of Bionor. “It eventually finds its way to treatment plants, and oil is one of the most difficult products to treat and eliminate at those plants, so using spent oil to produce biodiesel is environmentally friendly to an extremely high degree”.
Ausin says the annual consumption of used cooking oil at the Bionor plant is equivalent to about 88,185 tons of oil.
Bionor is one of the few companies using used oil for biodiesel production. “There are two reasons for this,” Ausin says: “First, there is a limited supply of used oil, and not all the oil used is collected. The second reason is that it takes a far greater amount of technology and investment to produce acceptable biodiesel from used oil than from virgin oil”.
The used oil collection focuses on two main areas: the restaurant trade and the domestic sector.
Almost all Spanish restaurants have a collection system in place, but the domestic collection industry is in its infancy. The oil is collected mainly by small companies that make arrangements directly with restaurants, bars, schools, factory canteens and so on.
“We’re moving into the oil collection business”, Ausin says “so we not only purchase from other collectors but are now also engaged in the acquisition of several collection companies”.
Bionor was founded more as an environmental company than an energy company. Its original purpose was to take care of collected used cooking oil. “We had to decide what to do with it,” Ausin says: “Biodiesel was the answer, and that’s what we founded the company to do”.
Accordingly, their environmental impact is a very sensitive matter.
“First of all,” says Ausin, “this is an industry that works with environmental concerns, so we have to start by setting an example ourselves.
Major environmental impacts include, for example, the water used in the process. This water has a chemical demand for oxygen of 15,000 ppm, and before it can be discharged into the river it has to be brought down to 100, which is a major challenge.
The other two main points are reduction of water consumption by re-using water to minimise clean water intake, and process improvements to reduce our consumption of catalysts and methanol, which are both expensive and highly contaminating”.
The main challenge at the Bionor biodiesel production plant has without a doubt been to achieve acceptable biodiesel quality from the used cooking oil – a raw material that changes characteristics from day to day. “The biggest challenge is to take that permanent heterogeneity and turn it into a standard fine end product,” says Ausin.
Bionor is currently operating two biodiesel plants in Spain (Alava) and Italy (Brescia) with a combined output of 137,750 tons. It is constructing five more plants in Spain and Brazil, which will add 990,000 tons of capacity this year. It is also to invest US$200 million to develop at least 247,105 acres of land into jatropha plantations in the Philippines.
The project is part of Bionor’s strategy to develop plantations on biodiesel feedstocks that do not compete with the food sector or contribute to deforestation.