Hyperspectral Sensing Techniques Applied to Bio-masses Characterization: The Olive Husk Case

Olive husk (OH) quality, in respect of constituting particles characteristics (olive stones and pulp residues as result after pressing), represents an important issue. OH particles size class distribution and composition play, in fact, an important role for OH utilization as: organic amendment, bio-mass, food ingredient, plastic filler, abrasive, raw material in the cosmetic sector, dietary animal supplementation, etc. . OH is characterised by a strong variability according to olive characteristics and olive oil production process. Actually it does not exist any strategy able to quantify OH chemical-physical attributes versus its correct utilisation adopting simple, efficient and low costs analytical tools. Furthermore the possibility to perform its continuous monitoring, without any samples collection and analysis at laboratory scale, could strongly enhance OH utilization, with a great economic and environmental benefits. In this paper an analytical approach, based on HyperSpectral Imaging (HSI) is presented. HSI allows to perform, also on-line, a full quantification of OH characteristics in order to qualify this product for its further re-use, with particular reference as bio-mass. HSI was applied to different samples of OH, characterized by different moisture, different residual pulp content and different size class distributions. Results are presented and critically evaluated. © 2011 IFIP International Federation for Information Processing

Testing an electrochemical method for treatment of textile dye wastewater

Wastewater from total dyeing and finishing stages (TDFW) and wastewater only from dyeing stage (DW) from a Textile cellulosic reactive azo dyeing process were treated separately by an electrochemical method using Ti/Pt as anode and Stainless Steel 304 as cathode. In this technique, sodium chloride was used as an electrolyte and the mixture was passed through an electrolytic cell. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) the COD, BOD of the wastewaters were substantially decreased using this electrochemical technique. A number of experiments were run in a batch 5 litre apparatus and the results of the electrochemical treatment on the two kinds of wastewaters are reported here. The results indicate that the electrochemical method used is feasible for treatment of textile dyeing wastewaters. Copyright (C) 2000 Elsevier Science Ltd. Wastewater from total dyeing and finishing stages (TDFW) and wastewater only from dyeing stage (DW) from a Textile cellulosic reactive azo dyeing process were treated separately by an electrochemical method using Ti/Pt as anode and Stainless Steel 304 as cathode. In this technique, sodium chloride was used as an electrolyte and the mixture was passed through an electrolytic cell. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) the COD, BOD of the wastewaters were substantially decreased using this electrochemical technique. A number of experiments were run in a batch 5 litre apparatus and the results of the electrochemical treatment on the two kinds of wastewaters are reported here. The results indicate that the electrochemical method used is feasible for treatment of textile dyeing wastewaters

Electrochemical oxidation of a textile dye wastewater using a Pt/Ti electrode

Textile dye wastewater (TDW) from a reactive azo dyeing process was treated by an electrochemical oxidation method using Ti/Pt as anode and stainless steel 304 as cathode. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) when the wastewater was passed through the electrolytic cell the organic pollutants were oxidized to carbon dioxide and water. A number of experiments were run in a batch, laboratory-scale, pilot-plant, and the results are reported here according to residence time and initial addition of HCl in raw wastewater. When of 2 ml of HCl 36% were added and after 18 min of electrolysis at 0.89 A/cm2, chemical oxygen demand (COD) was reduced by 86%, biochemical oxygen demand (BOD5) was reduced by 71%, ADMI color units were reduced by 100%, and TKN was reduced by 35%. The biodegradability of the wastewater was improved because the COD/BOD ratio decreased from 2.16 to 1.52. At the same time the efficiency of the electrode was about 170 g h-1 A-1 m-2. and the mean energy consumption was 21 kW h/kg of COD. These results indicate that this electrolytic method could be used for effective TDW oxidation or as a feasible detoxification and color removal pretreatment stage for biological post treatment. Copyright (C) 1999 Elsevier Science B.V

Studies of removal of chromium by model constructed wetland

Chromium is a pollutant present in tannery wastewater, its removal is necessary for protection of the environment. Penisetum purpureum, Brancharia decumbens and Phragmites australis were grown hydroponically in experimental gravel beds to determine their potential for the phytoremediation of solutions containing 10 and 20 mg Cr dm-3. These concentrations, similar to tannery wastewater after initial physico-chemical treatment were used with the aim of developing an economic secondary treatment to protect the environment. All the systems achieved removal efficiencies of 97 - 99.6% within 24 hours. P. purpureum and B. decumbens removed 78.1% and 68.5% respectively within the first hour. Both P. purpureum and B. decumbens were tolerant of the concentrations of chromium applied, but P. purpureum showed the greatest potential because its faster growth and larger biomass achieved a much greater chromium removal over the whole length of time of the experiment

Current and potential uses of composted olive oil waste

Food industry will have to focus on waste avoidance as well as utilisation of process waste. Application of clean technologies greatly enhances the safety and quality of the product as well as reducing the energy requirements and environmental impact of the food industry. The main environmental impacts of the food sector are aquatic, atmospheric and solid waste emissions. Nowadays, the main treatment method of solid wastes is composting, while recovery and reuse of by-products and wastes as raw materials stand for another effective option (http:// www.oulu.fi/resopt/wasmin/pap.pdf). Composted olive oil waste can find applications (1) as amendment in agriculture because of its high nitrogen and phosphorus content, (2) as a biofertiliser, with a mixture of compost with Sphagnum peat or commercial substrate finding use for ornamental plants growth and (3) as a biofilter for toxic metal removal. However, there are a number of disadvantages as well, such as large decline of soil germination capability, necrosis of the leaves and slow emission of secondary stems, and enhanced phytotoxicity, because of pH neutralisation technique, which should be seriously taken into account prior to opting for composting as a promising waste treatment alternative