# name
Bioplastic production from wastes and wastewater

# metadata.dc.description[].value
Treballs Finals de Grau d'Enginyeria Química, Facultat de Química, Universitat de Barcelona, Curs: 2014-2015, Tutor: Joan Mata Álvarez

# metadata.dc.description.abstract[].value
Dependence on conventional plastics and their boundless usage have resulted in waste
accumulation and greenhouse gas emissions. Part of a solution lies in using biodegradable
plastics such as polyhydroxyalkanoates (PHA), which can be produced by bacterial
fermentation. The interest in these biopolymers lies in its similar properties to conventional
plastics. However, its price is still too high to compete in the current market. One way to
produce PHA reducing the cost of production is to use wastes and wastewater as a raw
material. They have not only a great capacity to produce PHA with a high potential for
accumulation but also to reduce the costs of the waste and wastewater treatment. The process
to produce PHAs from waste consists of three steps: an anaerobic fermentation process, the
enrichment of the culture and the accumulation of PHA. The fermentation process, to produce
volatile fatty acids, is required when carbohydrate wastes are used as substrate. The main
challenge in PHA mixed culture processes is the enrichment of PHA-accumulating organisms,
which can be carried out with transient conditions of carbon supply, i.e. feast-famine regime.
This process configuration creates periods of excess and lack of external carbon substrate.
Following a certain period of time in the absence of external carbon substrate, a decrease of the
amount of intracellular components required for cell growth (RNA and enzymes) occurs.
Therefore, when carbon substrate becomes available again, the amount of growth enzymes
may not be enough to ensure that a maximum growth rate is reached. On the contrary, fewer
enzymes are required for PHA storage and, therefore, PHA storage can occur at a much faster
rate than cell growth, thus providing the cells with a means of rapidly consuming the available
external substrate. This work presents an economic analysis of PHA production by bacterial
fermentation from municipal wastes. Based on an annual production of 2503 tones of PHA, and
taking into account the performance of production processes of PHA is 0.33 g PHA/ g VFA-COD
approximately, the economic potential which is obtained is not still sufficiently positive. However, if this investigation line continues, it has been seen that the process can be viable and an
effective industrial wastewater treatment technology

# metadata.dc.source[].value
Treballs Finals de Grau (TFG) - Enginyeria Química

# metadata.dc.title[].value
Bioplastic production from wastes and wastewater

# metadata.dc.title.alternative[].value
Producció de bioplàstics a partir de residus i aigües residuals