Energy and Exergy Analyses of Rice Drying in a Novel Electric Stationary Bed Grain-Drying System with Internal Circulation of the Drying Medium

In our study, we developed a system to reduce both energy consumption and pollutant discharge during the drying process. We present a new technology, a stationary bed grain-drying test device based on the internal circulation of the drying medium (ICODM). A rice-drying experiment was carried out inside of it, and the influences of air temperature (AT) and air velocity (AV) on the energy and exergy efficiencies (EEE) as well as the improvement potential rate (IPR) and the sustainability index (SI) of the rice-drying process were studied. The following conclusions were obtained: when the rice was dried at a temperature of below 55 °C and an AV across the grain layer of 0.5 m/s, the average EEE during the drying process was 48.27–72.17% and 40.27–71.07%, respectively, demonstrating an increasing trend as the drying medium temperature increased. When the rice was dried using an AV across the grain layer in the range of 0.33–0.5 m/s and a temperature of 40 °C, the two values were 39.79–73.9% and 49.66–71.04%, respectively, demonstrating a decreasing trend as the drying medium flow velocity increased. IPR and SI were 4.1–8.5 J/s and 1.9–2.7, respectively, at a drying temperature of 30–55 °C and an AV of 0.33–0.5 m/s. These conclusions can provide helpful guidance for the optimization and control of the rice-drying process in terms of saving energy.

Graphite market imbalance will grow in the 2020s

Significance Price rises were underpinned by higher-than-expected steel production, requiring additional graphite for the industrial process. Prices were also supported by fresh environmental inspections of Chinese production hubs in several provinces, when plants with excessive emissions were banned from applying for a 'pollutant discharge permit' for up to three years. Impacts Given the size of its steel industry, China will continue to dominate the graphite market; it accounts for 55% of global demand. Graphite developers will benefit from investors’ interest in the battery sector. Talga’s Vittangi project in northern Sweden has been confirmed as the world's highest-grade graphite deposit. The unstable security situation in Mozambique raises questions about the near-term viability of graphite projects in the country.

Research on the Effect of an Environmental Protection Tax Policy on Haze Control in China—Empirical Analysis Based on Provincial Panel Data

This paper describes the construction of a model to explore the effectiveness of environmental protection taxes on haze emission reduction in China. The model is based on panel data from 30 provinces and cities in China, from 2003–2019. It is found that the current environmental protection tax has a significant inhibitory effect on haze. In addition, an upfront pollutant discharge fee can guide enterprises to significantly reduce the emission of haze-causing pollutants. A robustness test is conducted, using the variable substitution method of taking sulfur dioxide (SO2) as haze, and the research conclusions are consistent. We then put forward three specific suggestions: (1) Expand the scope of the environmental protection tax, gradually increase the tax rate, or adopt an excessive progressive tax rate. For example, China could consider including mobile pollution sources into the scope of taxation. (2) Increase the supervision and collection of the environmental protection tax. (3) Strengthen the multiple linkages between regional taxation departments and environmental protection departments, in order to form a collaboration between the departments in an effort to control haze and promote the sustainable development of the Chinese economy and the environment.

China pollutant discharge permits as a link between total emission control and water quality: a pilot study of the pesticide industry

The deficiency of China's current pollution discharge permit system lies in the failure to improve the water quality effectively. This paper discusses the premise that the water quality of a water environmental functional zone (WEFZ) is mostly affected by industrial pollution sources. By reviewing the related policy, we noted the link between total emission control, effluent limitations and pollutant discharge permits to configure a practical framework for pollutant discharge permits based on water quality. China's pollutant discharge permit system provides an administrative foundation for reducing polluters' total emissions at the scale of the WEFZ, and it is best implemented through the imposition of limitations on polluters to identify the related treatment technology levels. Owing to the importance of limitations, the methodology of limitation classification and the related treatment technology classification are presented for the pesticide industry. Additionally, a comprehensive analysis of the pollutant reduction potential for the pesticide industry is conducted to determine the current level of sewage treatment. More importantly, this study offers an innovative way to investigate pollutant reduction potential and provides an example that may be useful to other key industries.

A Study on a High-Purity Filter System of an Air Charger for an Air Respirator

The air charged through the air charger must be pure and free from impurities; hence, the role of a filter that removes pollutants, such as moisture, oil, and carbides is very important. The lifespan of the filter is approximately 50 h, and if exceeded, the purification function decreases rapidly. Therefore, it must be replaced periodically. However, economic and environmental problems occur in the process of replacing the filter. This study investigated the extension of the filter lifespan (60 h) and enhancement of the purification function. An auto drain system was installed. The pollutant discharge, maximum noise, and lifespan were confirmed through experiments and commissioned inspections to check the performance. The compatibility of the pollutant discharge function and the structure of the auto drain system was verified by checking the discharge of pollutants. In addition, the maximum noise was certified to be less than 80 dB according to the performance-standard. Finally, the charged air quality was analyzed after 60 h of use, and all the analyzed values were confirmed to be within the performance-standard range.

Phase II MS4 challenges: moving toward effective stormwater management for small municipalities

Federal regulations for municipal separate storm sewer systems (MS4s) in the United States have been in place since 1990 as part of the Nation Pollutant Discharge Elimination System (NPDES), aiming to reduce sediment and pollutant loads originating from urban areas. However, small-municipality (Phase II) MS4s frequently grapple with several challenges, resulting in a lack of stakeholder buy-in and actionable stormwater management plans. We identify five common challenges concerning MS4 requirements based on literature review, professional experience, and feedback solicited from stakeholders, municipal managers, and fellow professionals and offer real-world examples of efficient, effective MS4 frameworks and/or solutions. The five challenges are summarized as beliefs that: (1) agricultural land use is the largest pollutant contributor and the root cause of pollution problems; (2) stormwater management only benefits downstream communities; (3) large, expensive projects are required to comply with regulations; (4) maintenance, monitoring, and inspection of best management practices (BMPs) is overwhelmingly complex and expensive; and (5) a lack of direct funding makes complying with regulations an impossible task. These challenges are universal in nature for Phase II MS4 permittees and can create real barriers for effective stormwater management. However, we found many examples of methods or techniques to effectively address these five specific challenges, making them well-suited and important for discussion. BMPs can create tangible improvements for surrounding communities (e.g., reduced streambank erosion and flooding), and improved understanding of the structure and options within the MS4 program will help small municipalities make informed choices about management plans.