Cleaner Production

The environmental impact of the tanning industry is generally significant with outputs of wastes, i.e. high concentrations of organics, salts and heavy metals (chromium compounds), both in solid and liquid form, as a result. In order to bring the tanning industry more in line with present environmental thinking, various methods have been devised to reduce impacts. The underlying study proposes a modification of the method for unhairing-liming of hides where the unhairing-liming liquids are reused several times after being recharged by reduced quantities of chemicals. The study, therefore, aims at reducing both the economic and environmental costs of the unhairing-liming process. Experiments were carried out at lab scale with a simulation apparatus designed for the purpose. Life cycle assessment was used to evaluate the net environmental benefits of the modified method. The present value approach was used to evaluate the economic feasibility of the modified method. The quality of the...

Waste foundry sand (WFS) and fly ash D-Optimal mixture design/response surface methodology/design of experiments Statistical optimization Geopolymer concrete (GPC) Compressive strength A B S T R A C T This work examines the partial replacement of fine aggregates with waste foundry sand (WFS) and fly ash, process by-products, to synthesize geopolymer concrete (GPC). D-optimal mixture design of experiments was adopted to guide the proportion of mixture constituents (fine aggregates, WFS, and fly ash) to obtain desired responses (high compressive strengths). The experimentally measured responses/compressive strengths were successfully fitted to Scheffe polynomial model to obtain cubic models which represent compressive strengths of solidified GPC at 7 th day curing time (CS 7) and at 28 th day curing time (CS 28). The models were statistically evaluated by the standard error of design estimation and experimentally verified by comparing their predicted responses to the independently performed experiments. The models were subjected to analysis of variance (ANOVA) and residuals (diagnostics) for statistical significance and validation, respectively. The established models, hence obtained, were used to assess the impacts of relative proportions of mixture constituents at CS 7 and CS 28. It was observed that, although the highest compressive strength requires a high proportion of fine aggregates, yet, some mixture compositions could be proposed for better utilization of waste materials. Finally, the optimization was performed to maximize the usage of WFS and fly ash. A recipe was identified which yielded 18.9 N/mm² CS 7 and 22.3 N/mm² CS 28 by mere 32 wt. % contribution of fine aggregates in a (fine aggregates + WFS + fly ash) mixture. This study can be helpful in designing experiments and optimizing the utilization of similar waste materials into useful products.

The concepts of sustainability and sustainable development (SD) are often used by policy-makers, stakeholders and the private sector, as ‘selling points’ for their agendas and goals. Thanks to the wide, but also self-interpretive definition, the concepts allow various actors to make related pledges without necessarily undertaking any significant changes to their policies, strategies and actions. The purpose of this paper is to critically analyse the meaning of and approaches to sustainability and sustainable development which are being adopted and/or reformulated in the newly emerging bioeconomy policy debate of the European Union (EU). Understanding these concepts is crucially important given the growing importance of and adherence to bioeconomy-based policies and strategies by both individual EU Member States and the EU as a whole. The way bioeconomy policies perceive sustainability and SD as concepts will have profound implications not only on a practical level for policy implementation, but also on a conceptual level and for theoretical discourses surrounding sustainability and SD. The policy and narrative analyses illustrate that the current EU bioeconomy policy leans strongly towards prudentially conservationist, utilitarian and instrumental approaches to SD, as well as towards weak sustainability. We therefore argue that a balance between environmental, social and economic dimensions – as introduced in the Brundtland report – is missing within the EU bioeconomy policy framework, since economic dimensions and concerns prevail over environmental and social dimensions. In the light of possible negative consequences of biomass production we foresee an urgent need to define and broaden the scope of bioeconomy, as well as to include wider environmental and social concerns and safeguards. To tackle the shared challenges and constraints modern societies face today, a broader definition of sustainability needs to be adopted within the EU bioeconomy policy framework. Issues such as social justice, fairness and equity, social and environmental safeguards and local traditional knowledge in various concerned sectors should be taken into consideration.

Management is a significant factor in any business activity. It may be enhanced by the application of various management systems. These will help to obtain, organize, administrate, evaluate and control particulars: information, quality, environmental protection, health and safety and various resources (human, finance etc). Environmental management should embrace recent changes in the area of environmental protection, and be tailored to recent regulations in this field – entirely legal and economic, as well as take into use management systems that meet the requirements of the contemporary model for economic development. These changes are aimed at abandoning the conventional approach of environmental protection and replace it with sustainable development. The keys and the aims of Cleaner Productions are at present being implemented in various companies as a non-formalised environmental management system. This concept is suggested here as a proper model for practice where geothermal en...

This study assesses the environmental impact of four alternatives for reinforcing 100 m2 of concrete footpath (Functional Unit, FU) by using cradle to gate life cycle assessment (LCA), based on the Australian context. Specifically, the four options considered are a) producing steel reinforcing mesh (SRM), b) producing virgin polypropylene (PP) fibre, c) recycling industrial PP waste and d) recycling domestic PP waste. The FU yields 364 kg of SRM (in a) and 40 kg of PP fibres (in b, c and d), necessary to achieve the same degree of reinforcing in concrete. All the activities required to produce these materials are considered in the study, namely manufacturing and transportation, and also recycling and reprocessing in the case of industrial and domestic recycled PP waste fibres. These processes are individually analysed and quantified in terms of material consumption, water use, and emissions into the environment. This allows for the impacts from producing recycled fibres to be compar...

The United Nations proposed the Sustainable Development Goals (SDGs) to foster sustainable development, including tackling environmental challenges and adopting cleaner production practices worldwide. Green technology is crucial for the implementation of the SDGs. Currently, there is an urgent need to form a long-term sustainable investment mechanism for screening, evaluation, and promotion of appropriate green technology. Therefore, this study develops an integrated green technology framework to fill a gap in the literature by prioritizing green technologies' most critical attributes in Pakistan. Initially, we focus on eight leading green technology indicators: Environmental Quality, Resource Utilization, Agriculture & forestry, Green building, Energy utilization, Green Transport, Life Health, and Ecology Safety with the help of the fuzzy Delphi method. Fuzzy Analytical Hierarchy Process (FAHP) is employed to find primary and sub-indicators relative importance. Results reveal that Energy Utilization and agriculture & forestry are significant indicators. Supply chain and sustainable food security, Energy Recycling and Eco-Farming obtained the highest weight scores and are seen as essential among 43 sub-criteria. This study is among the first to assess the green technology indicators for cleaner production and sustainable investment to achieve sustainable development. This study's outcomes can help scholars, managers, government agencies, and decision-makers understand the importance of green technologies to achieve SDGs while simultaneously improving sustainability practices.