Calcium Phosphate Flocs and the Clarification of Sugar Cane Juice from Whole of Crop Harvesting

Abstract

Sugar cane biomass is one of the most viable feedstocks for the production of renewable fuels and chemicals. Therefore, processing the whole of crop (WC) (i.e., stalk and trash, instead of stalk only) will increase the amount of available biomass for this purpose. However, effective clarification of juice expressed from WC for raw sugar manufacture is a major challenge because of the amounts and types of non-sucrose impurities (e.g., polysaccharides, inorganics, proteins, etc.) present. Calcium phosphate flocs are important during sugar cane juice clarification because they are responsible for the removal of impurities. Therefore, to gain a better understanding of the role of calcium phosphate flocs during the juice clarification process, the effects of impurities on the physicochemical properties of calcium phosphate flocs were examined using small-angle laser light scattering technique, attenuated total reflectance Fourier transformed infrared spectroscopy, and X-ray powder diffraction. Results on synthetic sugar juice solutions showed that the presence of SiO2 and Na(+) ions affected floc size and floc structure. Starch and phosphate ions did not affect the floc structure; however, the former reduced the floc size, whereas the latter increased the floc size. The study revealed that high levels of Na(+) ions would negatively affect the clarification process the most, as they would reduce the amount of suspended particles trapped by the flocs. A complementary study on prepared WC juice using cold and cold/intermediate liming techniques was conducted. The study demonstrated that, in comparison to the one-stage (i.e., conventional) clarification process, a two-stage clarification process using cold liming removed more polysaccharides (≤19%), proteins (≤82%), phosphorus (≤53%), and SiO2 (≤23%) in WC juice but increased Ca(2+) (≤136%) and sulfur (≤200%).

Acidity rectified aggregation behaviour of colloids in sugarcane juice

“…The wide band observed at 3355 cm −1 is related to hydrogen bonding and hydroxyl (‐OH) stretching vibrations. The band at 2930 cm −1 arises from the C–H stretching vibration of the methyl group, which may be related to the presence of polysaccharides (Thai et al ., 2015). The band near 2930 cm −1 arises from the stretching vibration of the sp 3 C–H group in the alkyl chains of polysaccharides and proteins (Thai et al ., 2015; Shi et al ., 2021).…”

Rethinking on growth mechanism of Indian sugar industry

“…It may vary from increasing tonnage capacity to diversifying in related or unrelated product lines, for example, Integrated sugar complex is a diversified and valueadded phenomenon producing green energy-bio-ethanol (reduces Co 2 and Co 4 ), bio-power and bio-manure (Solomon, 2011;Ramaswamy et al, 2006). Whole sugarcane biomass (food cum bio-commodities) is usable that symbolizes that all leftovers across whole value chain can yield significant revenues (Thai et al, 2015). Campos-Ortiz and Oviedo-Pacheco ( 2014) found that mills having power generation plants are earning huge revenues and profits as compared to those who haven't adopted ISC model yet.…”

Effect of the clarification pH of sorghum juice on the composition of essential nutrients for fermentation

“…The changes in floc structure, along with the increasing Na + concentration, could be associated with the dispersive properties of Na + ions. The general increase in size may be due to electrostatic repulsion between calcium phosphate particles and/or electrostatic repulsion between the microflocs because of the dispersive action of Na + ions (Thai, Moghaddam and Doherty 2015).…”