Extraction of sugar cane juice using a diffuser suitable for energy cane processing

• Grant number: 15/22720-0
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• Start date: July 01, 2016
• End date: December 31, 2017
• Field of knowledge: Engineering - Mechanical Engineering - Mechanical Engineering Design
• Principal Investigator: Oscar Nishimura
• Grantee: Oscar Nishimura
• Company: OAM Obras e Restauração Ltda. - ME
• City: São Paulo
• Associated scholarship(s): 16/24355-0 - Extraction of sugar cane juice using a difuser suitable for energy cane processing, BP.PIPE

Abstract

There are two different ways to extract the sugarcane juice: using milling or a diffuser. The diffuser has a lower initial cost, operates with lower power consumption compared to millings, but its sugarcane processing capacity cannot be increased. The ethanol plants increase their harvest every year, through larger planted area and increased yield, but the diffuser limits this growth. Because of this limitation, despite the higher savings from the diffuser use, it is less used in ethanol plants than the millings. In addition, the growth of world second generation ethanol production, led to the development of a new variety of sugarcane, named energy cane. This biomass is high in fiber and low in juice, requiring processing adaptations. The objective of this project is the development of sugarcane juice extraction system trough diffusion, on consecutive tanks adapted to this new biomass, allowing a cyclical process, scalable according to demand and effective for this biomass with high fiber content. The technological challenges to be overcome are many, such as obtaining homogeneity and maximum performance in the extraction of such fibrous and little juiced biomass, to use compressed air instead of pumps to minimize power consumption, and to allow a continuous process. However, once the expected results are achieved, the project can be scaled up and incorporated into the first and second generation ethanol production processes, resulting in greater energy savings, higher yield and lower inhibitors production. A prototype will be built on a small scale to test the machine's settings. Such tests will be conducted in partnership with BioCelere, a company from the GranBio group. The equipment will have consecutive tanks and allow the customization of all parameters until the optimum operation is achieved. The yield of extraction will be measured by brix of the juice diluted coming from the Megaco crushed to leave the tank and analytical chemistry tests. Different residence times will be tested to evaluate the osmosis efficiency and generate parameters for scaling up. The volume of water used for soaking the cane in the diffusers will initially be 300% by mass relative to the cane fiber. However, smaller percentages will be tested for optimization and maximum process yield on a small scale and with a new biomass. It is expected to obtain similar or superior results in the prototype developed for energy cane when compared with sugarcane. This osmosis diffuser is expected to be more efficient due to the absence of air pockets on shredded cane mattresses. It is also expected decrease in water consumption for soaking, providing more concentrated juice and lower residual vinasse volume, improving fermentation conditions (less inhibitors) and logistics in the return of vinasse to the field. The diffuser can operate in two ways: as a cane diffuser, getting it after its passage through the grinder, or as bagasse diffuser, receiving biomass that passed the first milling. The diffuser, after developed and adapted for energy cane, can be incorporated in first and second generation ethanol plants, increasing the yield of juice extraction and reducing the power consumed in the process. It is the alternative with lower investment to increase milling capacity, with a gain in extraction yield and leaving more bagasse for the second generation ethanol production. (AU)