3.2 Low-temperature performance of BWCO blend with ET, BT, and DDCL
3.2.1 Influence of binary blends on the low-temperature flow properties of BWCO
The influences of blending ET or BT, and DDCL on the CP, CFPP and PP of BWCO are presented in Table 4.
As shown in Table 4, ET and BT exerted a parallel improvement of the cold flow properties of biodiesel. The PP, CFPP and CP of the binary blends decreased with the increase in the amount of ET and BT. Binary blends of BWCO-BT presented better cold flow properties than those of BWCO-ET. For BWCO-BT blends containing no more than 20 vol.% BWCO, the CFPP, CP, and PP decreased rapidly with the decrease in the biodiesel content from the initial values of −8 °C, −5 °C, and −9 °C, respectively.
Table 4 also shows that the cold flow properties of BWCO-ET and BWCO-BT blends are inferior to that of. BWCO-DDCL blends. As the blending DDCL in binary blends was increased to 70 vol.%, the CFPP decreased by 15 °C, 8 °C and 6 °C compared to those of pure BWCO, BWCO-ET, and BWCO-BT blends in 30:70 blending ratio, respectively. Further increase in DDCL in BWCO-DDCL blends led to rapid decreases in the values of PP, CFPP, and CP. More amounts of BWCO in blends caused more saturated FAMEs to hinder the low-temperature flow ability of biodiesel blends. However, in the biodiesel blends, the large dissolving capacity of BT and DDCL for the saturated FAMEs notably inhibited the growth of larger wax crystals at freezing cold temperatures.
Table 4 Influence of BWCO-DDCL, BWCO-ET and BWCO-BT binary blends on the CP, CFPP, and PP of BWCO.