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This paper aims to develop a construction and operation cost model of wastewater treatment for the paper industry in China and explores the main factors that determine these costs. Previous models mainly involved factors relating to the treatment scale and efficiency of treatment facilities for deriving the cost function. We considered the factors more comprehensively by adding a regional variable to represent the economic development level, a corporate ownership factor to represent the plant characteristics, a subsector variable to capture pollutant characteristics, and a detailed-classification technology variable. We applied a unique data set from a national pollution source census for the model simulation. The major findings include the following: (l) Wastewater treatment costs in the paper industry are determined by scale, technology, degree of treatment, ownership, and regional factors; (2) Wastewater treatment costs show a large decreasing scale effect; (3) The current level of pollutant discharge fees is far lower than the marginal treatment costs for meeting the wastewater discharge standard. Key implications are as follows: (l) Cost characteristics and impact factors should be fully recognized when planning or making policies relating to wastewater treatment projects or technology development; (2) There is potential to reduce treatment costs by centralizing wastewater treatment via industrial parks; (3) Wastewater discharge fee rates should be increased; (4) Energy efficient technology should become the future focus of wastewater treatment. [ABSTRACT FROM AUTHOR]

The control strategies for batch processes in the past are usually categorized into two levels. The higher level is economic optimization running at a low frequency and the lower one tracks the reference given at the higher level using MPC or PID. The lower level regards all of the disturbances as something to reject using a quadratics-based optimization objective. However, not all of the disturbances are unfavorable to batch processes; some of them would be helpful. In this paper, an economic optimization for batch processes is directly applied at the lower level. It replaces the conventional tracking strategy. With the collection of the information on disturbances in the previous batches, the iterative learning control strategy (ILC) can determine better operation profiles. ILC has the advantage of continuously improving the economic performance of the current batch with enriched information on disturbances from batch to batch. The convergence of the proposed ILC-based economic optimization is proved. To demonstrate the potential applications of the proposed design method, a typical dynamic batch reactor is applied. [ABSTRACT FROM AUTHOR]

Food losses and food waste (FLW) have become a global concern in recent years and emerge as a priority in the global and national political agenda (e.g., with Target 12.3 in the new United Nations Sustainable Development Goals). A good understanding of the availability and quality of global FLW data is a prerequisite for tracking progress on reduction targets, analyzing environmental impacts, and exploring mitigation strategies for FLW. There has been a growing body of literature on FLW quantification in the past years; however, significant challenges remain, such as data inconsistency and a narrow temporal, geographical, and food supply chain coverage. In this paper, we examined 202 publications which reported FLW data for 84 countries and 52 individual years from 1933 to 2014. We found that most existing publications are conducted for a few industrialized countries (e.g., the United Kingdom and the United States), and over half of them are based only on secondary data, which signals high uncertainties in the existing global FLW database. Despite these uncertainties, existing data indicate that per-capita food waste in the household increases with an increase of per-capita GDP. We believe that more consistent, in-depth, and primary-data-based studies, especially for emerging economies, are badly needed to better inform relevant policy on FLW reduction and environmental impacts mitigation. [ABSTRACT FROM AUTHOR]

China's rapid economic growth has caused serious environmental problems, resulting in the implementation of two major measures-end-of-pipe facilities and the phasing out of backward capacity-to reduce China's industrial emissions as part of its 11th Five-Year Plan (FYP, 2006-2010). It is important to determine whether China can meet the targets set forth in its 12th FYP (2011-2015) for industrial pollution reduction using these same solutions. In this paper, structural decomposition analysis (SDA) was used to identify the contributions of the adopted measures-as well as other underlying factors-and to evaluate the feasibility of the reduction target in China's 12th FYP. Results show that the decrease in major industrial pollutant emissions achieved during the 11th FYP resulted from improved technological efficiency, including end-of-pipe abatement efficiency and pollutant generation intensity. The same measures adopted during China's 12th FYP can address the problem of industrial wastewater emissions resulting from economic growth when the economic structure is kept constant. But it may not fulfill its commitment of reducing industrial atmospheric pollutants emissions unless the economic structure and growth patterns are drastically reformed. [ABSTRACT FROM AUTHOR]

This paper explores potential contributions of regional material flow accounting to the characterization of environmental pressures. With this aim, patterns of material extraction, trade, consumption, and productivity for the Spanish regions were studied within the 1996-2010 period. The main methodological variation as compared to whole-country based approaches is the inclusion of interregional trade, which can be separately assessed from the international exchanges. Each region was additionally profiled regarding its commercial exchanges with the rest of the regions and the rest of the world and the related environmental pressures. Given its magnitude, interregional trade is a significant source of environmental pressure. Most of the exchanges occur across regions and different extractive and trading patterns also arise at this scale. These differences are particularly great for construction minerals, which in Spain represent the largest share of extracted and consumed materials but do not cover long distances, so their impact is visible mainly at the regional level. During the housing bubble, economic growth did not improve material productivity. [ABSTRACT FROM AUTHOR]