Biodiesel
Biodiesel is a liquid synthetic biofuel obtained from natural lipids such as vegetable oils or animal fats, new and used, through industrial esterification and transesterification processes. It is used to prepare total and partial substitutes for petrodiesel or gasoil obtained from petroleum.
Biodiesel can be mixed with gasoil from petroleum refining in different quantities. Abbreviated notations are used depending on the percentage by volume of biodiesel in the mixture: B100 is used if it contains only biodiesel, in addition to other notations such as B5, B15, B30 and B50, where the numbering indicates the percentage of biodiesel in the mixture by volume.
Standards and regulation
Fatty acid methyl esters (FAME), known as biodiesel, are products of plant or animal origin whose composition and properties are defined by the European Union in standard EN 14214. There is an exception for the iodine value for Spain, which has been established as 140 rather than the 120 proposed by standard EN 14214.
In Spain, biodiesel is regulated by Royal Decree 61/2006, dated 31 January, which determines the specifications for gasolines, gasoils, fuel oils and liquid petroleum gases, and regulates the use of certain biofuels. For biofuel mixtures containing petroleum derivatives exceeding 5% of fatty acid methyl esters or bioethanol, a specific label is mandatory at points of sale.
Guascor engines operating with Biodiesel
Guascor believes that the growing use of biodiesel and mixtures with higher percentages of biodiesel makes approval for this fuel source a strategic market advantage for original equipment manufacturers (OEM) and end users.
The addition of these engines to the product line approved for use with biodiesel is a result of the successful tests conducted with fuel mixtures ranging from very low percentages to values of 100%.
The biodiesel used, both pure and in mixtures, must comply with the latest version of standard ASTM D6751 or EN14214.
To minimise the risks associated with the use of biodiesel in our engines, it was deemed appropriate to start by conducting a follow-up study of an engine using 10% biodiesel and 90% diesel, and gradually increasing the amount of biodiesel used to 100%. These tests, in which the percentage of biodiesel is gradually increased, have made it possible to locate the problems associated with the use of biofuel in the engine without causing catastrophic failures. This helps us to optimise our preventive maintenance guidelines and costs, and to develop modifications to the engine in order to optimise the economical use of biodiesel..
As a result, the range of engines for electrical power generation that are capable of operating with biodiesel has been liberated to 100%, with the same thermal efficiency as diesel. Specific consumption is higher, depending on the PCI of the biodiesel, and emissions have improved except for NOx, which has increased.
Recommendations for the storage and supply of Biodiesel
Due to the properties of biodiesel, which are poor when cold, and its stability issues and corrosive potential, a series of recommendations have been issued regarding biodiesel storage and supply.
These are :
- Short storage periods for biodiesel. Maximum 4-6 weeks
- Materials in the viton seals
- The paints in the tanks must be acrylic
- Fuel/water separator filters at the tank outlet
- Heat resistors in the storage tank
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