The conversion of chicken manure to bio-oil by fast pyrolysis. III. Analyses of chicken manure, bio-oils and char by Py-FIMS and Py-FDMS

Fast pyrolysis of chicken manure produced the following three fractions: bio-oil Fraction I, bio-oil Fraction II, and a char. In a previous investigation we analyzed each of the four materials by curie-point pyrolysis-gas chromatography/mass spectrometry (CpPy-FDMS). The objective of this article is to report on the analyses of the same chicken manure and the three fractions derived from it by fast pyrolysis. We now used pyrolysis-field ionization mass spectrometry (Py-FIMS) to characterize the three fractions. In addition, the two bio-oil materials were analyzed by pyrolysis-field desorption mass spectrometry (Py-FDMS). The use of both Py-FIMS and Py-FDMS produced signals over significantly wider mass ranges than did CpPy-GC/MS, and so allowed us to identify considerably larger numbers of constituents in each material. Individual compounds identified in the mass spectra were classified into the following twelve compound classes: (a) low molecular weight compounds (< m/z 62); (b) carbohydrates; (c) phenols + lignin monomers; (d) lignin dimers; (e) n-alkylbenzenes; (f) N-heterocyclics; (g) n-fatty acids; (h) n-alkanes; (i) alkenes; (j) sterols; (k) n-diols and (l) high molecular weight compounds (> m/z 562). Of special interest were the high abundances of low-molecular weight compounds in the two bio-oils which constituted close to one half of the two bio-oils. Prominent among these compounds were water, ammonia, acetic acid, acetamide, propyl radical, formamide and hydrogen cyanide. The main quantitative differences between the two bio-oils was that bio-oil Fraction I, as analyzed by the two mass spectrometric methods, contained lower concentrations of low-molecular weight compounds, carbohydrates, and N-heterocyclics than bio-oil Fraction II but was richer in lignin dimers, n-alkylbenzenes and aliphatics (n-fatty acids, n-alkanes, alkenes, and n-diols). Of special interest were the N-heterocyclics in the two bio-oils such as pyrazole, pyrazoline, substituted pyrroles, pyridine and substituted pyridines, substituted methoxazole, substituted pyrazines, indole and substituted indoles. Fatty acids in all four materials ranged from n-C(9) to n-C(33), alkanes from n-C(9) to n-C(40), alkenes from C(10:1) to C(40:1) and diols from n-C(7) to n-C(29). The chicken manure, bio-oil Fraction I, and char each contained about 4% sterols with cholesterol, ethylcholestriene, ergosterol, ethylcholestene, ethylcholesterol and beta -sitosterol as major components. Semi-quantitative estimates of the total materials identified by Py-FIMS were: chicken manure: 61.1%; bio-oil Fraction I: 81.3%; bio-oil Fraction II: 78.6%; char: 61.3%; and by Py-FDMS were: bio-oil Fraction I: 65.4%; bio-oil Fraction II: 70.0%.     

Dynamic subsurface explosive vapor concentrations: Observations and implications

Conventional vapor intrusion characterization efforts can be challenging due to background indoor air constituents, preferential subsurface migration pathways, sampling access, and collection method limitations. While it has been recognized that indoor air concentrations are dynamic, until recently it was assumed by many practitioners that subsurface concentrations did not vary widely over time. Newly developed continuous monitoring platforms have been deployed to monitor subsurface concentrations of methane, carbon dioxide, oxygen, hydrogen sulfide, total volatile organic constituents, and atmospheric pressure. These systems have been integrated with telemetry, geographical information systems, and geostatistical algorithms for automatically generating two‐ and three‐dimensional contour images and time‐stamped renderings and playback loops of sensor attributes, and multivariate analyses through a cloud‐based project management platform. The objectives at several selected sites included continuous monitoring of vapor concentrations and related physical parameters to understand explosion risks over space and time and to then design a long‐term risk reduction strategy. High‐frequency data collection, processing, and automated visualization have resulted in greater understanding of natural processes, such as dynamic contaminant vapor intrusion risk conditions potentially influenced by localized barometric pumping. For instance, contemporaneous changes in methane, oxygen, and atmospheric pressure values suggest there is interplay and that vapor intrusion risk may not be constant. As a result, conventional single‐event and composite assessment technologies may not be capable of determining worst‐case risk scenarios in all cases, possibly leading to misrepresentation of receptor and explosion risks. While dynamic risk levels have been observed in several initial continuous monitoring applications, questions remain regarding whether these situations represent special cases and how best to determine when continuous monitoring should be required. Results from a selected case study are presented and implications derived. © 2011 Wiley Periodicals, Inc.     

Improved methodology to assess modification and completion of landfill gas management in the aftercare period

Municipal solid waste landfills represent the dominant option for waste disposal in many parts of the world. While some countries have greatly reduced their reliance on landfills, there remain thousands of landfills that require aftercare. The development of cost-effective strategies for landfill aftercare is in society’s interest to protect human health and the environment and to prevent the emergence of landfills with exhausted aftercare funding. The Evaluation of Post-Closure Care (EPCC) methodology is a performance-based approach in which landfill performance is assessed in four modules including leachate, gas, groundwater, and final cover. In the methodology, the objective is to evaluate landfill performance to determine when aftercare monitoring and maintenance can be reduced or possibly eliminated. This study presents an improved gas module for the methodology. While the original version of the module focused narrowly on regulatory requirements for control of methane migration, the improved gas module also considers best available control technology for landfill gas in terms of greenhouse gas emissions, air quality, and emissions of odoriferous compounds. The improved module emphasizes the reduction or elimination of fugitive methane by considering the methane oxidation capacity of the cover system. The module also allows for the installation of biologically active covers or other features designed to enhance methane oxidation. A methane emissions model, CALMIM, was used to assist with an assessment of the methane oxidation capacity of landfill covers.     

Innovative use of a pressure‐pulse injection tool to increase transmissivity in a collection trench

Pressure‐pulse injection tools are widely used in the oil and gas extraction industry to increase well production yields; however, they have been sparingly used in the environmental industry. These injection tools work by applying a pressure pulse to the subsurface that can open subsurface pore throats in unconsolidated material, increasing yields or increasing a radius of influence from a substrate injection. Collection trenches at an industrial site were installed to increase recovery of No. 2 fuel oil in the subsurface and maintain hydraulic control of the contaminant plume. However, after operating for seven years, significant reduction in recovery was observed. Diminished recovery was attributed to biofouling, iron fouling, and/or excessive scaling. A pilot test was conducted in 2009 to determine if a pressure‐pulse injection tool could be used to inject an antifouling agent and rehabilitate two of the site collection trenches. The pilot test was successful in increasing the transmissivity of both trenches, with an order‐of‐magnitude increase in groundwater recovery at Collection Trench 1 and a 50 percent increase in recovery at Collection Trench 2. The trench rehabilitation using the pressure‐pulse injection tool was conducted at two other site collection trenches in 2010 with similar success and is now proposed as part of regular maintenance of the trenches on an as‐needed basis. © 2011 Wiley Periodicals, Inc.     

Continuous Determination of Carbon Monoxide and Hydrocarbons in Air by a Modified Infrared Analyzer

The original goals of this project¹ were to establish the shape of a smoke curve for fine suspended particulates in New York City comparable to the International Smoke Curve used in British and other European practice, and to relate two commonly used reporting units of surface concentration, μg/m³ (European practice) and Coh/1000 lineal feet (United States practice), to each other. While not directly a goal of the project, it was essential in the course of work to study the relationship between particulate density readings taken for one hour and two hour sampling periods. Progress toward achievement of these goals is presented in the following pages.     

Access for all? Barriers to accessing woodlands and forests in Britain

This paper presents results from research that identified and analysed barriers to accessing British woodlands and forests. This paper aims to contribute to an understanding of access and accessibility and to inform the design of policy and management interventions to encourage increased access by under-represented social groups. A brief review of policy and academic literature places the issue of inclusive woodland and forest access in the context of contemporary debates surrounding public health, well-being, diversity and the perceived role of public green space. There follows an analysis of quantitative and qualitative research findings, informing the presentation of a working typology of barriers. The typology is structured around the access needs of various social groups, allowing an analysis of the social distribution of barriers. The findings indicate the deep-seated psychological, emotional and socio-cultural nature of some barriers and highlight the need for carefully designed interventions that may lie outside the conventional remit of woodland management. This paper will be of particular interest to decision-makers and practitioners and to those involved in the design and delivery of policies, programmes and projects aimed at encouraging inclusive use of woodlands, forests and other types of green space.     

Applying DOE's Graded Approach for assessing radiation impacts to non-human biota at the INL

In July 2002, The US Department of Energy (DOE) released a new technical standard entitled A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota. DOE facilities are annually required to demonstrate that routine radioactive releases from their sites are protective of non-human receptors and sites are encouraged to use the Graded Approach for this purpose. Use of the Graded Approach requires completion of several preliminary steps, to evaluate the degree to which the site environmental monitoring program is appropriate for evaluating impacts to non-human biota. We completed these necessary activities at the Idaho National Laboratory (INL) using the following four tasks: (1) develop conceptual models and evaluate exposure pathways; (2) define INL evaluation areas; (3) evaluate sampling locations and media; (4) evaluate data gaps. All of the information developed in the four steps was incorporated, data sources were identified, departures from the Graded Approach were justified, and a step-by-step procedure for biota dose assessment at the INL was specified. Finally, we completed a site-wide biota dose assessment using the 2002 environmental surveillance data and an offsite assessment using soil and surface water data collected since 1996. These assessments demonstrated the environmental concentrations of radionuclides measured on and near the INL do not present significant risks to populations of non-human biota.     

Applications of mulch biowalls—three case studies

Mulch biowalls are proving to be an effective means of generating reducing conditions for the in situ anaerobic reduction of contaminants in groundwater that are amenable to the reduction process. Mulch is an inexpensive and readily available substrate that provides a long‐lasting carbon and electron donor source for the stimulation of the anaerobic reduction process in groundwater. Examples of contaminants that are amenable to the biotic anaerobic reduction process include: chlorinated alkenes and alkanes, explosives, perchlorate, some metals, and petroleum hydrocarbons. The microbial degradation of cellulose fibers (mulch) is arguably the oldest reduction process known and is evident anywhere that plant material, soil, and water are present together. This article presents three case studies discussing three different uses of mulch biowalls to stimulate the anaerobic bioremediation of contaminants in shallow soils and groundwater. © 2009 Wiley Periodicals, Inc.