Power generation by high head water in a building using micro hydro turbine—a greener approach

Demand for green energy production is arising all over the world. A lot of emphasis is laid in making the buildings green. Even a small amount of energy savings made contribute to saving the environment. In this study, an idea is proposed and studied to extract power from the high head water in the pipelines of a building. A building of height 15 m is considered for this study. Water flowing in the pipe has sufficient energy to run a micro hydro turbine. The feasibility of producing electrical energy from the energy of pipe water is found. The motivation is to find the feasibility of generating power using a low-cost turbine. The experimental setup consists of micro turbine of 135 mm diameter coupled to a 12-V DC generator; LEDs and resistors are employed to validate the results. The theoretical calculations were presented using the fundamental equations of fluid mechanics. The theoretical results are validated using experimental and numerical results using CFD simulation. In addition, exergy analysis has been carried out to quantify the irreversibilities during the process in the system.     

Aftermarket remanufacturing strategic planning decision-making framework: theory & practice

The authors of this paper offer an aftermarket, remanufacturing (or reman) decision-making framework (RDMF), developed, based on a comprehensive set of strategic factors (Subramoniam et al., 2009a) derived from an in-depth literature review and case studies. RDMF is also grounded on results from an industry survey and related theory. The survey targeted Original Equipment (OE) suppliers that are involved in automotive OE production and also provide remanufactured (or reman) parts for the aftermarket, which includes the Original Equipment Service (OES) and/or the Independent Aftermarket (IAM) business. A response rate of 42% was obtained for the survey; the respondents were business unit managers or chief engineers from 18 companies in the United States and Europe who are actively involved in the reman businesses. The survey results helped the authors of this paper to prioritize and confirm the strategic decision-making factors from previous research. The key factors considered to be important by more than 50% of the survey respondents, constituting roughly 79% of the strategic factors were then incorporated into RDMF. The RDMF will be useful for aftermarket supplier companies in general and in particular, will be useful for automotive suppliers, involved with OE and aftermarket production.     

Removal of arsenic from water by electrocoagulation

In the present study electrocoagulation (EC) has been evaluated as a treatment technology for arsenite [As(III)] and arsenate [As(V)] removal from water. Laboratory scale experiments were conducted with three electrode materials namely, iron, aluminum and titanium to assess their efficiency. Arsenic removal obtained was highest with iron electrodes. EC was able to bring down aqueous phase arsenic concentration to less than 10 microgl(-1) with iron electrodes. Current density was varied from 0.65 to 1.53 mAcm(-2) and it was observed that higher current density achieved rapid arsenic removal. Experimental results at different current densities indicated that arsenic removal was normalized with respect to total charge passed and therefore charge density has been used to compare the results. Effect of pH on arsenic removal was not significant in the pH range 6-8. Comparative evaluation of As(III) and As(V) removal by chemical coagulation (with ferric chloride) and electrocoagulation has been done. The comparison revealed that EC has better removal efficiency for As(III), whereas As(V) removal by both processes was nearly same. The removal mechanism of As(III) by EC seems to be oxidation of As(III) to As(V) and subsequent removal by adsorption/complexation with metal hydroxides generated in the process.     

Remanufacturing for the automotive aftermarket-strategic factors: literature review and future research needs

While the concepts of remanufacturing and reverse logistics are gaining popularity in practice, the available literature and theory on strategic decision making in these areas are limited. This paper is designed to address this gap, in particular, for the automotive industry aftermarket. In doing so, the authors reviewed literature pertaining to: customer demand(s), product design and development, cost-benefit analysis of reman, core (i.e., used product) supply management, reman competencies and skills, product life cycle strategies, reman and reverse logistics network design, relationships among key stakeholders, environmental considerations, regulations, and impact of emerging economies. The literature findings along with our experience in working with automotive reman products were used as inputs to guide the formulation of seven major propositions for the strategic factors in decision making within reman. The propositions were then tested through a case study. The case study reconfirmed many of the factors like product life cycle, regulations, etc. from the literature review and also identified new factors like OE customer requirements. Our results provide a foundation for further research for companies that deal with Original Equipment (OE) Sales, Original Equipment Service (OES), as well as Independent Aftermarket (IAM) business in the automotive industry.     

Modelling livelihoods and household resilience to droughts using Bayesian networks

Over the last four decades, the Indian government has been investing heavily in watershed development (WSD) programmes that are intended to improve the livelihoods of rural agrarian communities and maintain or improve natural resource condition. Given the massive investment in WSD in India, and the recent shift from micro-scale programmes (<500 ha) to meso-scale (~5000 ha) clusters, robust methodological frameworks are needed to measure and analyse impacts of interventions across landscapes as well as between and within communities. In this paper, the sustainable livelihoods framework is implemented using Bayesian networks (BNs) to develop models of drought resilience and household livelihoods. Analysis of the natural capital component model provides little evidence that watershed development has influenced household resilience to drought and indicators of natural capital, beyond an increased area of irrigation due to greater access to groundwater. BNs have proved a valuable tool for implementing the sustainable livelihoods framework in a retrospective evaluation of implemented WSD programmes. Many of the challenges of evaluating watershed interventions using BNs are the same as for other analytical approaches. These are reliance on retrospective studies, identification and measurement of relevant indicators and isolating intervention impacts from contemporaneous events. The establishment of core biophysical and socio-economic indicators measured through longitudinal household surveys and monitoring programmes will be critical to the success of BNs as an evaluation tool for meso-scale WSD.     

Plastic waste management in Jakarta,Indonesia: evaluation of material flow and recycling scheme

Journal of Material Cycles and Waste Management - In Jakarta, Indonesia, municipalities collect plastic mixed with other waste, scavengers recover plastic waste by picking through waste, and some...     

Adoption and adaptation of natural resource management innovations in smallholder agriculture: reflections on key lessons and best practices

Many smallholder farmers in vulnerable areas continue to face complex challenges in adoption and adaptation of resource management and conservation strategies. Although much has been learned from diverse experiences in sustainable resource management, there is still inadequate understanding of the market, policy and institutional failures that shape and structure farmer incentives and investment decisions. The policy and institutional failures exacerbate market failures, locking smallholder resource users into a low level equilibrium that perpetuates poverty and land degradation. Improved market access that raises the returns to land and labor is often the driving force for adoption of new practices in agriculture. Market linkages, access to credit and availability of pro-poor options for beneficial conservation are critical factors in stimulating livelihood and sustainability-enhancing investments. Future interventions need to promote joint innovations that ensure farmer experimentation and adaptation of new technologies and careful consideration of market, policy and institutional factors that stimulate widespread smallholder investments. Future projects should act as ‘toolboxes’, giving essential support to farmers to devise complementary solutions based on available options. Addressing the externalities and institutional failures that prevent private and joint investments for management of agricultural landscapes will require new kinds of institutional mechanisms for empowering communities through local collective action that would ensure broad participation and equitable distributions of the gains from joint conservation investments. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Wastewater re-use for peri-urban agriculture: a viable option for adaptive water management?

Urbanization is known to spur land modification in the form of conversion of common land to human settlements. This factor, combined with climate variability, can alter the duration, frequency and intensity of storm drain overflows in urban areas and lead to public health risks. In peri-urban regions where these risks are especially high it has been argued that, when domestic wastewater is managed, better prospects for freshwater water savings through swaps between urban water supply and irrigated agriculture may be possible. As a consequence of re-use of domestic wastewater, expenditure on inorganic inputs by farmers may decline and source sustainability of water supply could be enhanced. Given the fact that, at present, approximately 20 million ha of land worldwide is being cultivated by re-using domestic wastewater, this paper draws on evidence from India to explore: (1) the economic costs–benefits of wastewater reuse in the context of hypothesized links to climate variability; (2) the role of local farming practices, market conditions and crop variety in influencing wastewater reuse in agriculture; and (3) the role of inter-governmental financing in influencing the selection of technical adaptation options for collection, treatment and disposal of wastewater.     

Study of transient behaviour of modified Soxhlet apparatus for extraction of a bio-fuel oil from Crotalaria juncea seed

Extraction of Crotalaria juncea (Sunn hemp) oil from its seeds is important to study because of its proven promising clean fuel characteristics. Soxhlet-based solvent extraction with some modification has been tried to extract the oil. In a fluid-solid mass transfer system, where, solids are present as packed bed, dynamic behavior of bed can be described in terms of concentration of solute in solids/solvent-time profile. Some of the well-known semi-empirical models of adsorption dynamics are modified and applied since leaching of oil is just the reverse of the phenomenon of adsorption in porous media. Modified Bohart-Adams model (non-linear), modified Bed Depth Service Time (BDST) (linear), and modified Thomas model (non-linear forms) are applied. It is found that these models fit to the experimental result reasonably well. Results suggest that higher bed height, with proper shape (annular) of the bed, having a higher solvent velocity will work best. Comparing the error values (SSE, SAE, and ARE) in the four cases, it is very clear that the modified BDST model is the most suitable. In the light of transient study it is established that the modified Soxhlet apparatus with cylindrical and annular beds, performs best while leaching Crotalaria juncea oil from their seeds.