Biorefinery sustainability assessment

This article presents a comparative sustainability assessment of three biorefineries that produce liquid fuels used in current infrastructure. The three options considered are biochemical production of ethanol from grain and from cellulosic feedstocks and thermochemical production of Fischer‐Tropsch diesel from biomass‐derived syngas. These biorefineries were compared using numerous environmental, economic, and social metrics, with numerical values derived from a thorough review of recent literature. For each of the three biorefinery options, the metrics were not determined from a specific process design, but from a variety of different designs reported in literature. Where necessary, corn was selected as the feedstock for grain ethanol and switchgrass was selected for cellulosic ethanol and Fischer‐Tropsch diesel. These sustainability metrics were used in an Analytic Hierarchy Process decision analysis to compare the sustainability of the different biorefineries. Thus, a new decision‐making tool has been created in which the user can assign different weights to each category and its metrics. This tool was used to explore the influence of different weights, different market conditions, and uncertainties in the values of the metrics on the relative sustainability of the different options. Based on the results of this assessment, cellulosic ethanol biorefineries are modestly more sustainable than grain ethanol and Fischer‐Tropsch diesel. Grain ethanol was favorable economically whereas Fischer‐Tropsch diesel had the highest score on the societal metrics. © 2010 American Institute of Chemical Engineers Environ Prog, 2010Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88001/1/10516_ftp.pd

Challenges and Opportunities in the Hydrologic Sciences

This is the Table of Contents and Introduction of a Report published as Hornberger, G. M., E. Bernhardt, W. E. Dietrich, D. Entekhabi, G. E. Fogg, E. Foufoula-Georgiou, W. J. Gutowski, W. B. Lyons, K. W. Potter, S. W. Tyler, H. J. Vaux, C. J. Vorosmarty, C. Welty, C. A. Woodhouse, C. Zheng, Challenges and Opportunities in the Hydrologic Sciences. 2012: Water Science and Technology Board, Division on Earth and Life Studies, National Academy of Sciences, Washington, DC. 173 pp. Posted with permission.</p

ENRICHMENT, ISOLATION AND CHARACTERIZATION OF CHEMOLITHOAUTOTROPHIC ARSENITE OXIDIZING BACTERIA FOR REMOVAL OF ARSENIC FROM WATER PHASE

L. Nguyen Ai, A. Sato, D. Inoue, K. Sei, S. Soda, M. Ike,Enrichment of arsenite oxidizing bacteria under autotrophic conditions and the isolation and characterization of facultative chemolithoautotrophic arsenite oxidizing bacteria for removal of arsenic from groundwater, Water Science and Technology: Water Supply, vol. 12, no. 5, pp. 707-714, 2012Nguyen Ai Lea, Akiko Satoa, Daisuke Inouea, b,Kazunari Seia, b, Satoshi Sodaa, Michihiko Ike, Bacterial community succession during the enrichment of chemolithoautotrophic arsenite oxidizing bacteria at high arsenic concentrations, Journal of Environmental Sciences, vol. 24, no. 12, pp. 2133–2140, 2012

Canals spawn dams ? Exploring the filiation of hydraulic infrastructure

This article studies the aetiology underlying water management by exploring the social hermeneutics that determined its construction. It details how science, technology and political relations construct each other mutually, both producing and harnessing the scientific discourse on the environment. Supply management continues to prevail, in spite of contradictory claims, through the filiation process linking successive generations of water infrastructure. The case study of the Neste Canal inducing the construction of the Charlas Dam, allows the identification of three types of mechanisms participating in the construction of water deficits that now lead both proponents and opponents of dam construction to harness the environmental discourse. The first lies in the social construction of water science and technology. The second lies in the evolution of power relations among the various actors. The third lies in the insertion of the 'expert' within these power relations

Optimized coagulation for the removal of natural organic matter (NOM) from low alkalinity : hardness South African raw waters

Abstract This example is to demonstrate the layout of the first page of a paper for Water Science and Technology. The authors’ family names should be given in full; their forenames should be given as abbreviations. The title, authors' names and addresses should be indented 1.5 cm from the left-hand margin of the text area; the abstract is indented 1.5 cm from both margins. The abstract itself, set in 10 pt type like the authors' addresses, should start about 9 cm down from the top of the text area. It should be a single paragraph. Please do not make reference citations in the abstract and keep within the limit of 200 words. It is followed by your choice of up to six keywords, listed alphabetically and separated by semi-colons

Development of a kinetic model for elemental sulfur and sulfate formation from the autotrophic sulfide oxidation using respirometric techniques

©IWA Publishing 2009. The definitive peer-reviewed and edited version of this article is published in Water science and technology, vol. 59, núm. 7, p. 1323-1329, 2009. DOI: 10.2166/wst.2009.110 and is available at www.iwapublishing.com.A kinetic model for the elemental sulfur and sulfate production from the autotrophic sulfide oxidation has been proposed. It is based on two kinetic equations able to describe the simultaneous microbial consumption of oxygen and sulfide (OUR and SUR) as a function of a particular sulfide-oxidizing microorganism or its physiological state, these can be characterized by the assessment of their kinetic constants. The respirometric technique allowed to estimate the dynamic experimental OUR and SUR profiles, which were used to calibrate the kinetic model. The ratio OUR/SUR was proposed to predict the sulfide oxidation extent and then the fate of sulfide to elemental sulfur and sulfate.Peer ReviewedPostprint (author's final draft

Converting rain into drinking water: Quality issues and technological advances

With growing pressures on water supplies worldwide, rainwater harvesting is increasingly seen as a viable option to provide drinking water to an ever expanding population, particularly in developing countries. However, rooftop runoff is not without quality issues. Microbiological and chemical contamination have been detected in several studies, well above local and international guidelines, posing a health risk for consumers. Our research explores the use of silver ions, combined with conventional filtration and settling mechanisms, as a safe and affordable model for purification that can be applied on a small scale. The complete systems were installed and tested in rural communities in a Mexican semi-arid region. Efficiencies up to 99.9% were achieved in the removal of indicator microorganisms, with a marked exception where cross-contamination from external seepage occurs. Sites without overhanging branches or with relatively clean surfaces show an absence of total coliforms in the untreated runoff, compared with others where values as high as 1,650 CFU/100 ml were recorded. Thus, given adequate maintenance, the system can successfully deliver high quality drinking water, even when storage is required for long periods of time. © IWA Publishing 2011

Water Security for Texas: A Post-Secondary Education Pathway for the Water Workforce

Water and wastewater industry leaders in Texas and throughout the United States have expressed concern over high rates of retirement eligibility and difficulties finding and attracting workers ready to fill job openings, especially for work in smaller systems. In late January 2018, the U.S. Government Accountability Office released a report on water workforce readiness and a bill was introduced in the U.S. Senate to establish a water infrastructure workforce development program. Concern over existing education of workers in water and demographic information projecting future workforce readiness are commonly cited as signaling a coming crisis for the water industry. An alignment of post-secondary training and industry needs is recommended to meet coming workforce employment requirements for Texas and the nation. A model post-secondary education pathway for water science and technology is described to support water workforce readiness