Cst viscosity
![cst viscosity cst viscosity](https://www.researchgate.net/profile/Ahmad-Ragab-3/publication/268684879/figure/tbl5/AS:669081497784328@1536532868278/Kinematic-viscosity-cSt-of-diesel-fuel-and-the-prepared-nanoemulsions-of-different.png)
![cst viscosity cst viscosity](https://media.cheggcdn.com/media/bb6/bb6f7ce3-8ad1-4281-a84c-058a21847f79/phpoJHzGH.png)
The EN 14214 is more rigorous for this parameter, and some microalgae-based biodiesels do not meet this specification as seen in Table 10.4 because most microalgae species show a high degree of unsaturation and long-chain fatty acid contents. Factors such as growing conditions and lipid extraction may affect the fatty acid profile and consequently the biodiesel properties ( Soares et al., 2014). The accreditation covers the calibration of glass capillary viscometers, the determination of kinematic and dynamic viscosity (including that of viscosity standards and the viscosity certification of customer samples), and the provision of calibration services. However, in another study ( Song et al., 2013), this microalgae-based biodiesel was according to the specification (4.5 mm 2 s − 1). CANNON Instrument Company has received ISO/IEC 17025 accreditation for technical competence in the field of calibration through A2LA. For the Brazilian standard, only Phaeodactylum tricornutum presents biodiesel with KV (2.9 mm 2 s − 1) slightly lower than the minimum established ( Gangadhar et al., 2015). The biodiesel viscosity from oilseeds, animal fat, and microalgae are in accordance with the ASTM standard. As shown in Table 10.4, biodiesel presents greater viscosity than diesel due to a higher degree of unsaturation and by oxidation reactions that can modify the fatty acid composition during storage, transportation, and temperature change ( Knothe and Steidley, 2007). Kinematic viscosity (KV) is a physical property related to the chain length and degree of saturation thus, this criterion is associated with oxidation stability and IV. For a small industrial pump with 100 mm impeller radius and 1450 rpm rotational speed, pumping liquid with 150 cSt corresponds to impeller Reynolds number of Re 10.
![cst viscosity cst viscosity](https://i2.wp.com/mechguru.com/wp-content/uploads/2011/09/Viscosity2.jpg)
However, for a pump to be economically efficient, the maximum recommended liquid viscosity is 150 cSt 1. Tzovenis, in Microalgae-Based Biofuels and Bioproducts, 2017 10.4.3 Kinematic viscosity The viscosity can be increased to 1000 cSt by using specific impellers.