A straightforward route to sensor selection for IoT systems

The Internet of Things (IoT) allows for remote management and monitoring of many aspects of everyday life at the individual and industrial levels. However, designing these systems within constraints of cost and operational context can be a real challenge. The sensor network must be strategically designed, which means selecting the most appropriate sensors to collect a specific measurement in a specific environment and then optimizing their deployment and utilization. To facilitate sensor selection, we propose a straightforward, color-coded, three-sieve selection tool and demonstrate the efficacy of this method through real-life exemplars. The selection tool could be applied to other kinds of technologies as well

Comparative study of production of Bio-Indigo by Pandoraea sp. in a two phase - fed batch and continuous bioreactor

Indigo, is blue of blue jeans, a synthetic dye used on large scale all over the world. Chemical production of the dye is taking a new route towards bacterial production to overcome the environmental effects that are posed by the synthetic blue powder (Indigo). In the present work a strain Pandoraea sp. isolated from the oil contaminated soil is found to produce blue pigment which is analyzed qualitatively as indigo using UV-visible scan and Thin Layer Chromatography (TLC). The strain is used for indigo production at lab scale in two different bioreactor configurations first the fed batch mode and second continuous mode using two phases. The two phases consisting of medium carrying biomass and the second phase of silicone oil carrying substrate indole. The use of second phase allows higher concentration of substrate injection reducing the inhibition effects of the substrate as well as act as a partitioning agent for removal of the product. In two phase study, the maximum indigo produced was seen to be 0.068 g/L after 22 hours of substrate injection into the Fermentor in a fed batch mode. The maximum yield obtained in this configuration was 19%. For commercial production of bio-indigo a continuous operation is required, which was studied in a bioreactor with 2.5 liter capacity under the optimized conditions. The maximum indigo produced was found to be 0.052 g/L after about 72 hours of operation. The results showed decrease in the production of indigo in continuous mode as compared to fed batch operation, which may be due to the insufficient time available for the bacteria to bio-transform indole into indigo

Design of a Robust Adaptive Controller for the Pitch and Torque Control of Wind Turbines

In this paper, robust adaptive control is designed for pitch and torque control of the wind turbines operating under turbulent wind conditions. The dynamics of the wind turbine are formulated by considering the five degrees of freedom system (rotor angle, gearbox angle, generator angle, flap-wise deflection of the rotor blade, and axial displacement of the nacelle). The controller is designed to maintain the rotor speed, maximize the aerodynamic efficiency of the wind turbine, and reduce the loads due to high wind speeds. Gaussian probability distribution function is used for approximating the wind speed, which is given as the disturbance input to the plant. The adaptive control algorithm is implemented to 2 MW and 5 MW wind turbines to test the robustness of the controller for varying parameters. The simulation is carried out using MATLAB/Simulink for three cases, namely pitch control, torque control, and the combined case. A case study is done to validate the proposed adaptive control using real wind speed data. In all the cases, the results indicate that the rotor speed follows the reference speed and show that the designed controller gives a satisfactory performance under varying operating conditions and parameter variations

Anaerobic co-digestion of food waste and septage – A waste to energy project in Nashik city

The samples for food waste (FW) and septage were collected from six localities of Nashik city. Physical and chemical characterizations of the wastes were carried out. A Biomethanation potential (BMP) assay was developed to determine the ultimate biodegradability and associated methane yield during the anaerobic methanogenic fermentation of organic substrates. BMP assays of individual substrate, FW and septage were carried out by taking into account the volatile solids/total solids (VS/TS) ratio of each while keeping the inoculum’s VS constant. BMP of FW and septage mixture was carried out in different ratios (1:1, 1.5:1, 2:1, 1:1.5 and 1:2) to find the optimum mixing ratio for maximum biogas production. The average methane yield for different locality FW was found to be 503±17.6 ml/g VS and for septage it was 56 ±10.8 ml/g VS. Based on the above results, the total biogas yield and total methane yield for 10 tons of FW would be 2178 m3/d and 1306 m3/d respectively. The total biogas yield and total methane yield for 20 m3 of septage would be 65m3/d and 39m3/d respectively. From our co-digestion studies we also conclude that the mixture of FW to septage at 1:2 ratio gives 2896 m3/day of biogas. The role of septage is to provide essential trace elements that are required for methanogens

Biogas generation potential by anaerobic digestion for sustainable energy development in India

The potential of biogas generation from anaerobic digestion of different waste biomass in India has been studied. Renewable energy from biomass is one of the most efficient and effective options among the various other alternative sources of energy currently available. The anaerobic digestion of biomass requires less capital investment and per unit production cost as compared to other renewable energy sources such as hydro, solar and wind. Further, renewable energy from biomass is available as a domestic resource in the rural areas, which is not subject to world price fluctuations or the supply uncertainties as of imported and conventional fuels. In India, energy demand from various sectors is increased substantially and the energy supply is not in pace with the demand which resulted in a deficit of 11,436 MW which is equivalent to 12.6% of peak demand in 2006. The total installed capacity of bioenergy generation till 2007 from solid biomass and waste to energy is about 1227 MW against a potential of 25,700 MW. The bioenergy potential from municipal solid waste, crop residue and agricultural waste, wastewater sludge, animal manure, industrial waste which includes distilleries, dairy plants, pulp and paper, poultry, slaughter houses, sugar industries is estimated. The total potential of biogas from all the above sources excluding wastewater has been estimated to be 40,734 Mm3/year.Anaerobic digestion Biogas Biomass Bioenergy Solid waste Cattle manure

CO2 from industrial off-gases for algae cultivation

In this work, technical solutions for capturing CO2 from CO2-containing off-gases from industry for feeding an algal cultivation were qualitatively evaluated. Also, cultivation of algae using both vent gases from a sour gas processing plant and flue gases from a coal-fired combined heat and power (CHP) plant was studied. The most promising methods for CO2 capture seem to be those that absorb CO2 directly into the cultivation media by using separate bubbling carbonation columns, both for open ponds and closed photobioreactors. This lowers the energy requirements in comparison to flue gas injection and also enables the remainder of the flue gas to be led out through the existing flue gas stack. The low capacity of water to dissolve CO2 can be improved by addition of alkaline salts. The growth of two green algae, one diatom, and one cyanobacterium was examined in a laboratory-scale, batch-mode comparative cultivation experiment, using both pure CO2 and flue gas from a coal-fired CHP plant. No significant statistical differences in the growth were observed between the experiments except for the cyanobacterium, which had a decreased growth during flue gas cultivation. Microalgae suitable for cultivation using vent gases from a sour gas processing plant were screened by employing a 20 L photobioreactor. Based on these experiments, a certain mixture of microalgae exhibited rapid growth and better tolerance towards in terms of time taken to reach pH 7. A small-scale CO2 capture and cultivation pilot was set up using a 0.3 m3 CO2 absorption column for absorbing CO2 from vent gas in connection to a 0.2 m3 raceway pond. The produced algae was harvested and sent for anaerobic digestion studies. The experiments were successful, with a microalgae yield of 18 g/m2/day achieved, which on anaerobic digestion yielded about 0.4 m3 CH4/kg volatile solids fed