6 research outputs found
Biorefinery for Rehabilitation of Heavy Metals Polluted Areas
Biorefinery applied in heavy metals polluted lands proposed here describes a process starting from soil (polluted and unfit for food and feed production) and solar energy stored in carbohydrates (regarded here as a solar energy carrier) to deliver liquid and gaseous biofuels, green building block chemicals for the market and return the rest of the matter (not delivered to the market) as fertilizer and soil improver, extracting the heavy metals from the polluted soil for safe reuse and remediating the land to sustainably deliver resources in a circular bioeconomy. The circular economy proposed in this chapter offers a novel approach to land rehabilitation by investigating the opportunity for economic value creation as an integral part of a rehabilitation strategy and production of biomaterials and biofuels as renewable energy carriers. The case study approached here can be developed in a complete circular biorefinery process and value chain enabling the use of heavy metals polluted lands for production of renewable energy and biomaterials and at the same time serve as a means of rehabilitation of contaminated lands. This biotechnology can be transferred and adapted in other areas improper for food/feed production due to contamination human industrial activity
Removal of N and P in a Rotating Biological Contactor Plant: Case Study Agnita, Romania
The wastewater treatment plant of Agnita, Romania was designed with a rotational biological contactor system for a population of approximately 9500, but for environmental protection reasons it must comply with regulations concerning nitrogen and phosphorus designed for larger communities. In order to achieve the prescribed limits for these pollutants, we have used a 40% FeCl3 solution, continuously added to the distributor, without changes in flow or equipment. Its use boosts the removal of ammonia nitrogen, and phosphorus, bringing them within the limits and with reasonable cost. To determine the ferric chloride to be used we considered, aside from the pollutant load, the water temperature, and introduced a new parameter: specific removal power that enabled us to optimize the volume of FeCl3. A major contribution to nitrogen removal was achieved by the denitrification bacteria favored by the presence of ferric ions, which also precipitate phosphorus. The results of this study, performed since September 2021, enable us to continue to use this method and enlarge its application to other plants owned by the local operator
Pathogenic Microorganisms from Raw Milk of Different Animals
Milk is an ideal environment for microbial growth and for this reason the separation of some pathogens is very important. The analysis of milk regarding pathogenic microorganisms is a clear indicator of hygienic quality and this influences the dairy production. Samples of raw milk from cow, goat and sheep were analyzed for pathogens like Staphylococcus aureus and Escherichia coli. The microorganisms found in milk directly affect the human health and can cause a public illness if the unpasteurized milk is used in the food industry
Lyophilisation of Lactic Bacteria with Probiotic Effect for Production of Starter Cultures
Selection of lactic acid bacteria (LAB) for probiotic effect and preservation of LAB by lyophilized have been
studied. The two LAB strains belonging to Lactobacillus plantarum and Lactobacillus pentosus producing
bacteriocins in inhibitory concentration for colibacilli were selected from a total of 17 tested strains. The selected
strains were further tested for their ability to survive the preservation process by lyophilisation. Two methods of
preserving LAB by lyophilisation were tested and the viability of cells in lyophilized products was monitored in
order to obtain products used as starter cultures. The presence of inhibition zones in mixt cultures indicates the
ability of LAB to inhibit the growth of E. coli bacteria due to the synthesis of bacteriocins. During three years period,
the viability of lyophilized LAB was monitored. Obtained data indicate that starter cultures of LAB can be stored in
the lyophilized state for at least three years in dark and cool place, and the inoculation rate can be increased after this
period by 50% if the starter culture was preserved and stored by applying the described techniques