A preliminary investigation on water quality of coalbed natural gas produced water for beneficial uses: a case study in the Southern Qinshui Basin, North China

Coalbed natural gas (CBNG) is an important unconventional natural gas resource with large reserves in China and receives much attention these years. The CBNG production is accomplished by extracting large volumes of produced water from the aquifer. The CBNG-produced water is commonly managed by discharging into nearby disposal ponds in the Southern Qinshui Basin (SQB), which provides an opportunity for water source for nearby irrigation, livestock, wildlife, and human drinking water. However, utilization of this nontraditional water source in the SQB is hindered by limited knowledge of water quality, practically oxidation/reduction potential (OPR), electrical conductivity (EC), sodium adsorption ration (SAR), and trace element chemistry data. The objective of this study was to collect CBNG-produced water samples at discharge points in the SQB and investigate their water quality principally, including physicochemical parameters, major ions parameters, and trace element parameters. Discharge points were sampled from five main CBNG blocks in the SQB including SZ, ZZ, FZ, CZ, and PZ blocks from July 31, 2013 to August 11, 2014. A composite geochemical data was created with the test results from 145 produced water samples, resulting in information on 40 constituents/parameters. The resulting constituents/parameters were compared to common water use criteria of China to determine possible beneficial uses. Results suggest that the CBNG-produced waters from SQB are characterized by dominated Na-HCO₃ type waters, with approximately 12% Na-SO₄ and Na-Cl type waters. The observed TDS ranges from 615 to 4376 mg/L with 91% are less than 3000 mg/L, and Na⁺ and HCO₃^- are the dominating determinants of the TDS content. The EC values vary from 930 to 3844 μS/cm, ranging from class 3 to class 5 based on the suitability for irrigation. The CBNG-produced waters in SQB generally exhibit higher SAR values (avg. 41.98). Among the 25 detected trace elements in CBNG-produced waters from SQB, elements of environmental concerns include aluminum, iron, selenium, barium, manganese, nickel, and plumbum because their concentrations exceed the related Chinese regulatory standards for human drinking. The commonly constituents exceeding standards for human drinking water, livestock water, poultry water, and irrigation water include fluorinion, pH, and TDS. Besides, targeted reduction of SAR and EC also needs to be treated for most of the produced waters if used for irrigation. In contrast, the CBNG-produced waters in SQB are the most suitable for livestock water, because approximately 88% of the CBNG-produced waters are suitable for livestock drinking if the fluorinion is reduced.

Green tea (Camellia sinensis) and l-theanine: Medicinal values and beneficial applications in humans-A comprehensive review

Green tea (Camellia sinensis) is a famous herb, and its extract has been extensively used in traditional Chinese medicinal system. In this context, several studies have revealed its health benefits and medicinal potentialities for several ailments. With ever increasing scientific knowledge, search for safer, potential and novel type of health-related supplements quest, scientists are re-directing their research interests to explore natural resources i.e. medicinal herbs/plant derived compounds. Green tea consumption has gained a special attention and popularity in the modern era of changing lifestyle. The present review is aimed to extend the current knowledge by highlighting the importance and beneficial applications of green tea in humans for safeguarding various health issues. Herein, we have extensively reviewed, analyzed, and compiled salient information on green tea from the authentic published literature available in PubMed and other scientific databases. Scientific literature evidenced that owing to the bioactive constituents including caffeine, l-theanine, polyphenols/flavonoids and other potent molecules, green tea has many pharmacological and physiological functions. It possesses multi-beneficial applications in treating various disorders of humans. This review also provides in-depth insights on the medicinal values of green tea which will be useful for researchers, medical professionals, veterinarians, nutritionists, pharmacists and pharmaceutical industry. Future research emphasis and promotional avenues are needed to explore its potential therapeutic applications for designing appropriate pharmaceuticals, complementary medicines, and effective drugs as well as popularize and propagate its multidimensional health benefits.

Decision support for environmental management of industrial non-hazardous secondary materials: New analytical methods combined with simulation and optimization modeling

Non-hazardous solid materials from industrial processes, once regarded as waste and disposed in landfills, offer numerous environmental and economic advantages when put to beneficial uses (BUs). Proper management of these industrial non-hazardous secondary materials (INSM) requires estimates of their probable environmental impacts among disposal as well as BU options. The U.S. Environmental Protection Agency (EPA) has recently approved new analytical methods (EPA Methods 1313-1316) to assess leachability of constituents of potential concern in these materials. These new methods are more realistic for many disposal and BU options than historical methods, such as the toxicity characteristic leaching protocol. Experimental data from these new methods are used to parameterize a chemical fate and transport (F&T) model to simulate long-term environmental releases from flue gas desulfurization gypsum (FGDG) when disposed of in an industrial landfill or beneficially used as an agricultural soil amendment. The F&T model is also coupled with optimization algorithms, the Beneficial Use Decision Support System (BUDSS), under development by EPA to enhance INSM management.