A case study on waste minimisation and wastewater treatment in starch and noodle factories

A medium scale Mung Bean starch factory was taken in this study to assess the pollution caused by various streams in starch and noodle factories, and to provide the basic information for wastewater management in them. This study shows that the wastewater from starch processing unit with 46~54 tons of production capacity is the main polluting source, contained high values of COD and SS. Also the specific water consumption to process one ton Mung Bean in 16~25m3 is higher that theoretically required one. Methods have been proposed for minimizing and treating the wastewater produced by the factory to overcome the pollution problems. One of the alternatives is to use water in a controlled way by making optimum flow rates on the tab valves, in which water consumption can be brought down. However, bio-treatability of wastewater can be used for treating the total wastewater due to the suitability in characteristics.

A case study on waste auditing in an ice cream factory

The management of the ice cream factory concerned in this study strongly felt the importance of undertaking a waste audit of its biggest waste generator, the ice cream plant. Ice cream wastewater constitutes as much as 74% of the total volume of wastewater discharged by the company to the central treatment plant of the Industrial Estate in which the factory is situated. Generation of ice cream wastes is attributed to the high consumptive use of water in the plant for washing and cleaning operations. As a result of waste auditing, methods were proposed to save water and to segregate the waste, and to modify the existing wastewater treatment system of the ice cream plant for better treatment efficiency.

Waste auditing and its applications in improving the dyeing industry environment

A case study on the application of cleaner production opportunities for waste minimization in dyeing industry is discussed in this paper which was conduced by Carl Duisberg Gesellschaft (CDG) South East Asia Program Office in collaboration with several Thai institutions. A waste audit was conducted as a first step in a dyeing factory, which leads to propose water reuse and waste segregation in order to implement cleaner production for waste minimization. Further more lab-scale experiments were conducted to find optimum treatment methods for the waste streams.

Evaluation of cassava peel waste as lowcost biosorbent for Ni-sorption : equilibrium, kinetics, thermodynamics and mechanism

The feasibility of cassava peel waste for Ni-sorption is evaluated in this work. The biosorbents are characterized by Boehm titration, Fourier transform-infra red (FTIR) spectroscopy, Nitrogen sorption, scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis (e.g. elemental mapping) and X-ray photoelectron spectroscopy (XPS). Adsorption experiments are performed in batch mode at 30 °C (303.15 K), 45 °C (318.15 K) and 60 °C (333.15 K). The performance of several temperature dependence forms of isotherm models e.g. Langmuir, Freundlich, Sips and Toth to represent the adsorption equilibrium data is evaluated and contrasted. Sips model demonstrates the best fitting with the maximum uptake capacity for Ni(II) ions of 57 mg/g (0.971 mmol/g) at pH 4.5. For kinetic data correlation, pseudo-second order model shows the best representation. The chemisorption mechanism and thermodynamics aspect are also discussed.

Harvesting waste thermal energy using a carbon-nanotube-based thermo-electrochemical cell

Low efficiencies and costly electrode materials have limited harvesting of thermal energy as electrical energy using thermo-electrochemical cells (or “thermocells”). We demonstrate thermocells, in practical configurations (from coin cells to cells that can be wrapped around exhaust pipes), that harvest low-grade thermal energy using relatively inexpensive carbon multiwalled nanotube (MWNT) electrodes. These electrodes provide high electrochemically accessible surface areas and fast redox-mediated electron transfer, which significantly enhances thermocell current generation capacity and overall efficiency. Thermocell efficiency is further improved by directly synthesizing MWNTs as vertical forests that reduce electrical and thermal resistance at electrode/substrate junctions. The efficiency of thermocells with MWNT electrodes is shown to be as high as 1.4% of Carnot efficiency, which is 3-fold higher than for previously demonstrated thermocells. With the cost of MWNTs decreasing, MWNT-based thermocells may become commercially viable for harvesting low-grade thermal energy.

Global positioning systems in the AFL : worthwhile or waste of time?

Global Positioning Systems (GPS) in the Australian Football League (AFL) are the big-ticket item that sees clubs trying to gain any competitive advantage over their opposition that they can. This paper explores whether the current application of GPS by clubs is worthwhile or a waste of time from three core perspectives: technical, organisational and personal. Issues include poor data storage and analysis, inaccurate units, lack of appropriate business processes in place, and resistance to use. Although many of these issues can be addressed through improved technology, resolving the organisational and personal issues will require a change in mindset to ensure the use of GPS in the AFL is a worthwhile endeavour. The paper concludes that the current use of GPS devices in the AFL is a waste of time.

Comparison of advanced waste heat recovery systems with a novel oil heating system

Latest trends in waste heat recovery include systems like Thermo Electric Generation (TEG), Rankine cycle, and active warm up systems. The advantages and disadvantages of different approaches are critically discussed and compared with a novel and effective oil heating system that can deliver between 7% and 12% reductions of CO2 emissions and fuel consumption. The comparison includes the expected CO2 and fuel saving potential related to the legal drive cycle as well as real world driving, effects on regulated exhaust emissions, utilisation of resources, maintenance and service, vehicle performance, comfort, noise, and durability.