THE USE OF STATISTICAL QUALITY CONTROL TOOLS TO MONITOR PRODUCTION OF THE ETHANOL PROCESS.

In order to analyze the fermentation and treatment of yeast used to produce the biofuel ethanol. The researcher presents a case study on the application of statistical quality control. The following performance metrics were taken into account while identifying the crucial elements of the fermentation and treatment process: milling capacity, loss in distillation, loss in final effluent, indeterminate loss, accident risks, and costs associated with poor quality. Each performance indicator received a score to represent the effect it had on the process. Analysis was also done on the relationship between the performance indicators and specified process variables. The analysis identified seven variables as being critical: Temperature in the fermentation vats, Alcoholic concentration in the fermentation vats, Brix of the mash, Temperature of the mash, Alcoholic concentration in the vats of yeast treatment, Viability in the fermentation vats and Infection in the fermentation vats. Control charts were used to monitor the critical variables. Sampling frequencies were determined by examining the previous impacts of each critical variable on the fermentation process. Two hundred daily samples of each variable were used to plot the control charts. The data was divided into four periods, each of them with fifty daily samples in chronological order on which capability analysis was carried out.

The monitoring of the fermentation and treatment process sought to determine the existing inefficiencies in the production of ethanol. The presented results indicated some variables presented low or moderate variability, namely Temperature on the fermentation vat, Brix of the mash, Alcoholic concentration in the fermentation vats, Temperature of the mash and Alcoholic concentration in the vats of yeast treatment. Variables that presented high variability were Viability in the fermentation vats and Infection in the fermentation vats.

Reference

Sagawa, J. K., & Yamada, R. I. (2013). The Application Of Statistical Quality Control Tools To Monitoring Ethanol Process Production. Brazilian Association of Industrial Engineering Journal, 1-14. Retreived from http://www.abepro.org.br/biblioteca/enegep2013_tn_sto_178_015_22238.pdf