Acid induced degradation of the bentonite component used in geosynthetic clay liners

Bentonite is a natural clay mineral widely used in the mining and solid waste containment industry, for example, as a soil mixture for the construction of seepage barriers, or as a component of geosynthetic clay liners (GCLs), to provide low hydraulic conductivity. However, degradation of bentonites generally occurs when permeated with acid solutions, such as encountered in mining applications, which may influence physical properties, and particularly, the hydraulic performance of geosynthetic clay liners.In this paper, properties such as Atterberg limits, free swell index, and fluid loss of three bentonites were measured with different concentrations of sulphuric acid solutions. These properties were found to deteriorate even with low (0.015 M) sulphuric acid solutions; higher concentrations (up to 1 M) resulted in larger degradation. X-ray diffraction and infrared spectroscopy were used to monitor the change of bentonites after interaction with the acid solutions. Acid leachates in general result in the overall degradation of the hydraulic performance of geosynthetic clay liners and potentially, any bentonite-soil mixture.

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.

An evaluation of the suitability of selected waste products in feeds for three fish species

Five types of aquatic food industry waste products (carp offal, carp roe, fish frames, trout offal and surimi processing waste) together with fish meal were evaluated for their suitability as potential fish meal replacements, partially or wholly, in diets for three species (rainbow trout, Murray cod and shortfin eel) cultured in Australia, using a number of criteria.

The proximate composition of the ingredients on a dry matter basis including protein content, lipid and ash, varied considerably. The essential amino acid (EAA) contents of the waste products and fish meal decreased in the order: carp roe > fish meal > carp offal > 'surimi' processing waste > fish frames > trout offal. The results of cluster analysis of A/E ratios of waste products and fish whole body fell within three clusters. The EAAI of whole body tissue of Murray cod, rainbow trout and Australian shortfin eel however, were closest to fish meal, followed by fish frame waste and/or 'surimi' waste. The results on A/E ratios and EAAI did not conform to the raw data on TAA and EAA. Therefore, the study emphasizes the need to have a multi-prong approach to determine the suitability of ingredients for incorporation into fish feeds.

An analysis of factors influencing waste minimisation and use of recycled materials for the construction of residential buildings

Residential building construction activities, whether it is new build, repair or maintenance, consumes a large amount of natural resources. This has a negative impact on the environment in the form depleting natural resources, increasing waste production and pollution. Previous research has identified the benefits of preventing or reducing material waste, mainly in terms of the limited available space for waste disposal, and escalating costs associated with landfills, waste management and disposal and their impact on a  building company's profitability. There has however been little development internationally of innovative waste management strategies aimed at reducing the resource requirement of the construction process. The authors contend that embodied energy is a useful indicator of resource value. Using data provided by a regional high-volume residential builder in the State of Victoria, Australia, this paper identifies the various types of waste that are generated from the construction of a typical standard house. It was found that in this particular case, wasted amounts of materials were less than those found previously by others for cases in capital cities (5-10 per cent), suggesting that waste minimisation strategies are successfully being implemented. Cost and embodied energy savings from using materials with recycled content are potentially more beneficial in terms of embodied energy and resource depletion than waste minimisation strategies.

Wastewater reuse and treatment options for the dairy industry

Milk-processing plants generate significant quantities of wastewater with relatively high organic matter concentrations on a daily basis. In addition to environmental damage that can result from the discharge of these wastewaters into the natural waterways, the presence of products such as milk solids into wastewater streams represents a loss of valuable product for the plants. This paper presents a review of wastewater management practices employed by six milk-processing plants in Victoria, Australia. In all six plants investigated, milk powder represents a major product. During the milk powder production, water is evaporated, condensed and can be reused for various purposes with a significant impact on water usage. Other major products are anhydrous milk fat, cheese, butter, and UHT milk. The effectiveness of the practices was assessed through two main criteria: first through the water to milk intake ratio, and the waste volume coefficient. Both parameters characterise the plant efficiency in regard of water consumption and water reuse, Information on cleaning chemical usage and recovery was also assessed as part of the review. Significant discrepancies emerge between the plants first due to the products manufacturad and water reuse possibilities available in each plant. Second the type of treatment technologies used for condensate and cleaning solution influences the figures. One of the investigated plants is almost self-sufficient for water, emphasising the benefits gained from the use of technologies like membrane separations for condensate and cleaning solution treatment. In some cases, less cost-intensive technologies such as a clarifier are successful to improve cleaning agent recovery.

Globalisation and manufacturing strategy in the TCF industry

Purpose – The textiles, clothing, and footwear (TCF) industry has struggled in Australia since the government commenced dismantling tariffs. By sourcing from Asia, middlemen undercut established suppliers, and retail chains set benchmark low prices with their imported “house” labels. The policy-makers predicted that local producers would become more efficient, and export to make up for lost sales, but the media paints a picture of rising imports, retrenchments, and factory closures. The research objective was to discover what strategies the survivors (actually) employ in adapting to the pressures of globalisation.

Design/methodology/approach – More than 30 companies were involved in the study, ranging from small family businesses to subsidiaries of big multinationals. Each case study was based on an interview with a senior executive, normally followed by a plant tour. This methodology suits a fresh topic, as it avoids preconceptions and imposes no bounds.

Findings – Results show that the policy change was based on “pie in the sky” forecasts. Increasingly, TCF production is transferred to cheap offshore locations, generally via subcontracting plus the “badging” of foreign designs. To survive, local factories should focus on quality and customer service, preferably in niche markets (like uniforms), or for specific customer groups, and develop technologically advanced products. A move down the supply chain into retailing can also assist. Large multinational corporations that engage in foreign direct investment dominate the management literature.

Originality/value – This paper presents a different perspective, neglected in international operations management, whereby domestically oriented businesses attempt to defend themselves against the adverse consequences of globalisation.

A framework for material management in the building demolition industry

Conventional mechanical building demolition produces numerous solid wastes, most of which are sent to landfill directly and severely degrade the living environment. Just-in-time building demolition has been developed recently with a management strategy to facilitate waste reuse. Procurement management plays a significant role in just-in-time building demolition. In particular, the demolition tendering selection needs to consider contractors' environmental performance in addition to project costs. Moreover, the flow of building materials in a demolition project may be regarded as a supply chain involving the building owner, demolition contractor and material demanders. This paper develops a framework for salvaged materials management in the emerging demolition industry. The research is to promote the recycling and reuse of building demolition materials in order to achieve better environmental and financial performance for building demolition projects.

Sodium adsorption using activated alumina for application in the dairy industry

Basic activated alumina with negatively charged surface is considered as a potential adsorbent for a targeted molecule with positive polarity. Adsorption of sodium by basic activated alumina was investigated as a method for desalting dairy waste streams, in which sodium ion concentration averaged 600 mg/L. Sodium equilibrium and kinetic adsorption were investigated using basic activated alumina with synthetic brines. The results of equilibrium adsorption show that uptake of sodium by activated alumina is significantly higher when the pH is greater than 8 and increases as the pH of the brines increases until pH reaches around 10. The results of kinetic adsorption show that 90 hours were needed to reach equilibrium for sodium adsorption. Binding and diffusion processes are suggested to have taken place within the activated alumina.

Electronic waste exchange for just-in-time building demolition

Waste exchange is as a facilitator for construction and demolition waste deduction by reuse and recycling in construction projects. The just-in-time philosophy, which has been well cultivated in the manufacturing industry, is highly adoptable for demolition projects. Particularly, waste exchange that is usually performed after the actual demolition process can be shifted forward so that waste inventory from demolition is eliminated or reduced to facilitate waste reuse and recycling. A web-based waste exchange system is an ideal platform to enable communications among project participants before a demolition project commences so that waste materials can be sold before they are produced. Therefore, the productivity of the demolition project could be improved. This research paper aims to investigate and analyse the adoption of just-in-time philosophy in building demolition project management. It also describes the development of the proposed web-based waste exchange system that implements just-in-time demolition in detail, including its functionalities, information flows and major components.

CSR orientation and organisational performance in the Australian retail industry

This paper aims to contribute to current business ethics literature by conceptualising the relationship between organisational culture, corporate strategy, and target stakeholders and the formation of a CSR orientation. The paper will further explore whether corporate social responsibility policies and practices will result in an overall improved positional advantage for the firm and, as a consequence, positively enhance organisational performance. These relationships will be examined within the context of the retail industry in Australia, focusing on the food, clothing and textiles, and footwear sectors.

A prospective study on building quality : enforcement of control in the Australian housing industry

The Australian housing industry is beset with quality issues with repeated building defects causing problems with customer satisfaction and housing performance. These defects are caused by a combination of initial poor workmanship and poor quality materials and subsequently by poorly executed or inadequate maintenance. These poor work practices increase the cost and maintenance of housing. The waste and rectification work generated by such practices means that the housing industry generally is not engaged with sustainability. Building Control is part of achieving quality of building output. Whilst the Australian Building Code has regulations for initial-build material quality and workmanship, there is no continuing control and effective enforcement over a house over its life span. Sustainability is not dealt with as a topic at all in the Building Code with only energy efficiency concerns regulated. Inadequate knowledge transfer, to the mainly small builders who produce the majority of Australia’s housing, is seen to be a key issue. Mechanisms to make the transfer of knowledge to those who need to use it need to be improved. Building regulations, for example, could be more visual and accessible in their content and small builders should be encouraged to update their knowledge and skills. This comparative research will guide industry service providers in improving their performance and suggest how overall housing quality can be improved (thereby reducing wasteful practices), by considering more appropriate mechanisms for knowledge transfer among industry service providers in the Australian housing industry.

Molecular characterization and enzymatic hydrolysis of flavanoid extracted from citrus waste

The citrus fruit processing industry generates substantial quantities of waste rich in phenolic substances, which is a valuable natural source of polyphenols (flavonoids) such as naringin and its disposal is becoming a major problem. In the US alone, the juice processing of oranges and grapefruit generates over 5 Mt of citrus waste every year. In the case of India, about 2.15 Mt of citrus peel out of 6.28 Mt of citrus fruits are produced yearly from citrus juice processing. In case of Australia, about 15-40% of citrus peel waste is generated by processing of citrus fruit (0.85 Mt). Thus Isolation of functional compounds (mostly flavanoids) and their further processing can be of interest to the food and pharmaceutical industry. This peel is rich in naringin and may be used for rhamnose production by utilizing α-L-rhamnosidase (EC 3.2.1.40), an enzyme that catalyzes the cleavage of terminal rhamnosyl groups from naringin to yield prunin and rhamnose. We recently purified recombinant α-L-rhamnosidase from E. coli cells using immobilized metal-chelate affinity chromatography (IMAC) and used it for naringin hydrolysis. The purified enzyme established hydrolysis of naringin extracted from citrus peel and thus endorses its industrial applicability for producing rhamnose. Infrared (IR) spectroscopy confirmed molecular characteristics of naringin extracted from citrus peel waste.

Hydrolysis of citrus peel waste with recombinant rhamnosidase for bioenergy generation

Large amounts of Citrus peel (rich in poly-phenolic compounds) are generated as a by-product of the juice processing industry. Development of alternative, higher valued products utilizing peel waste from grapefruit, oranges, Valencia and other citrus fruit would benefit citrus juice processors by providing them with means to profitably process their peel waste and to avoid environmentally hazardous dumping. Citrus peel waste [CPW, comprised of peel, membranes and juice vesicles] contains a high level of polyphenols and has been used for the production of animal feed, single-cell protein, fibre, enzyme(s), immobilization support & bio-sorbent for heavy metal removal. Naringin (a major tri-hydroxy flavonoid glycoside) is available in large amounts in citrus peel, processed juice and can be extracted from citrus peel waste1. The extracted naringin is further hydrolysed by rhamnosidase to produce D-rhamnose for the production of ethanol and other fermentation products. We have produced a recombinant enzyme2 that has the ability to catalyse the cleavage of terminal rhamnoside groups from naringin to prunin and rhamnose. We have recovered important sugar “D-rhamnose” from the processed waste which would be utilized for ethanol production3. This presentation will summarize current efforts to develop an enzymatic treatment which would facilitate the economical processing of citrus waste for bioenergy generation.

Lessons learned practices in the UAE construction industry

The failure of learning from our mistakes or those of others, has generated unnecessary waste of time and costs, in the construction industry, due to its project based, fragmented and unstable nature. Lessons Learned, as an important way of improving projects performance, is analyzed in this study, with the aim to explore the current practice of Lessons Learned in the UAE construction industry. A literature review has revealed what “Lessons Learned” is under different contexts, and focused on various factors influencing a Lessons Learned Programme. The research method of a series of structured interviews, followed by an on line questionnaire, is adopted in this study. It was found that although the concept of Lessons Learned is quite familiar by most of professionals in the project management in the UAE construction industry, Lessons Learned practice is mainly performed in an informal way (individually or ad hoc). As for barriers for Lessons Learned practice, Culture factors, such as “Afraid to be blamed for mistakes” and “lack of learning culture” (1st and 2nd rank) influence significantly in Lessons Learned practice. It is also found that a formal lessons learned programme does exist in some organizations. However, with the lack of a dedicated Lessons Learned repository and Lessons Learnt system, Lessons Learned has yet a long way to reach its potential.