Search Results (5)

Tanneries generate copious amounts of potentially toxic sludge and effluent from the processing of skins and hides to leather. The effluent requires remediation before discharge to protect the receiving environment. A range of physicochemical methods are used for pre- and post-treatment, but biological secondary remediation remains the most popular choice for the reduction of the organic and macronutrient fraction of tannery effluent. This review provides an update and critical discussion of biological systems used to remediate tannery effluent. While the conventional activated sludge process and similar technologies are widely used by tanneries, they have inherent problems related to poor sludge settling, low removal efficiencies, and high energy requirements. Treatment wetlands are recommended for the passive polishing step of beamhouse effluent. Hybrid systems that incorporate anoxic and/or anaerobic zones with sludge and/or effluent recycling have been shown to be effective for the removal of organics and nitrogenous species at laboratory scale, and some have been piloted. Novel systems have also been proposed for the removal and recovery of elemental sulfur and/or energy and/or process water in support of a circular economy. Full-scale studies showing successful long-term operation of such systems are now required to convince tanneries to modernize and invest in new infrastructure. Full article

The article aims to identify the firm-level effects of public support within the Polish Investment Zone (PIZ) on firms’ employment located in lagging regions of Poland, signalling insights into sustainable employment creation. Utilising a difference-in-differences framework and accounting for controls, including the firms’ size, age, leverage, other public aid programmes, subsidies, and firm-level fixed effects, our objective is to ascertain the average treatment effects (ATEs) of the programme, particularly concerning the creation of additional workplaces. To ensure the reliability of our findings, we conducted robustness checks utilising alternative econometric approaches and scrutinise changes in the duration of both the pre- and post-treatment periods. No significant ATEs were observed in the year of the treatment or in one to three years following treatment. This outcome remains robust to variations in the econometric approach, the set of variables considered, and alterations in the length of both pre- and post-treatment periods. This article contributes to an ongoing discussion marked by a lack of consensus regarding the effectiveness of special economic zones in fostering sustainable employment and reducing unemployment rates by presenting the effects of the PIZ and directing policy attention towards more qualitative aspects of created workplaces, fostering sustainable employment. Full article

The present study introduces the concept of ecological cost of heating modeled on the economic cost of heating. A method of determining these costs is also proposed. This method allows for an analytical description of the ecological as well as economic net present value of a thermal insulation investment. Consequently, it is possible to determine the optimal values for ecological reasons of the heat transfer coefficient of the building external wall and the thickness of thermal insulation. The present study uses life-cycle assessment (LCA) analysis to determine the environmental impact of thermal insulation materials used to insulate the external vertical wall and to determine the environmental impact of thermal energy production in the energy phase of the building’s life cycle. Various variants characteristic of Polish conditions were studied. Different types of construction materials of the wall, types of heat sources, thermal insulation materials and climate zones occurring in Poland were considered. For all analysed variants, the obtained thermal insulation thickness, optimum for ecological reasons, was much larger than the optimum for economic reasons. Even at the thickness of thermal insulation optimum for economic reasons, the investment was profitable for ecological reasons, i.e., a reduction in environmental load was obtained as a result of the thermal insulation investment. On the basis of the conducted study, it can be concluded that it is preferable to use thermal insulation thicknesses larger than required by current regulations and larger than optimum for economic reasons. The ecological benefits of thermal insulation investments are then significantly greater, with not much smaller economic benefits. Full article

Special economic zones (SEZs) differ in terms of the scope and principles of functioning, they have the same objective: to attract investments and create jobs and simultaneously generate benefits for municipalities and their residents. However, in order to make the activity of SEZs and their further development possible and acceptable, activities undertaken in these areas should be consistent with the concept of sustainable development. Therefore, in addition to the leading economic benefits in the development of municipalities social and environmental ones should also be expected. The activity of the entities investing in SEZs certainly arouses some doubts as to their involvement in the search for balance between three pillars of sustainable development. The objective of the research was to assess the concept of special economic zones taking into account measurable economic, social and environmental criteria accompanying the idea of sustainable development. The research included the analysis of selected results of the activity of Polish municipalities. Analysis of variance (ANOVA) applied to independent groups indicated that the municipalities functioning in the area of SEZs differ in a positive way from other municipalities in terms of the analyzed scope. Full article

In Poland, 82% of forests are State-owned, and only 17% of forests constitute private property. Each year, forests are converted to other land-use types, mainly for road construction. The afforestation rate on privately-owned low-productivity land is decreasing steadily. The owners and perpetual usufructuaries of this kind of land are eligible to government subsidies to cover establishment expenditures in whole or in part, provided that the afforestation scheme complies with the local zoning plan or an outline planning permission. The above creates a dilemma for farmers—is this a profitable option of managing low-productivity land? Owners of small farms particularly often face such dilemmas. Owners of small farms, which consist of low-yield agricultural land, can be regarded as investors operating on the real estate market, but those investors have features characteristic of agricultural producers. This study relied on the net present value (NPV) criterion, which is popularly used to assess the effectiveness of investments on the real estate market. A financial feasibility assessment performed with the use of such method in view of afforestation statistics and the 5% discount rate on the Polish forest market revealed the highest increase in net cumulative cash flows in the first five years, followed by a gradual decrease in successive years. The first negative cash flow was reported in year 20. NPV would remain negative because farmers would be charged with periodic maintenance expenditures until the stand reaches harvestable age at approximately 40 years. The longer the investment period, the lower the profits, even if discount rate is excluded. Investments of the type are difficult to terminate because forests younger than 20 years are difficult to sell at a price that covers growing outflows. Afforestation projects are also influenced by other economic and non-economic factors. The paper validates the research hypothesis that afforestation is a long-term investment that delivers benefits for future generations. Full article