<p> The use of wood pellet boilers for residential space heating has significantly increased over the past decade. Wood pellets are a biomass-based renewable energy made by pelletizing debarked wood fiber. Compared to log wood and wood chips, wood pellets have higher energy density, relatively uniform fuel quality, easier to automate their use, and therefore, are being more widely used.</p><p> A typical wood pellet heating system has three components: the boiler (energy generation unit), the thermal energy storage (TES) tank (energy storage unit), and the building (energy consumption unit). The three components form into two loops: the boiler to TES tank loop and the TES tank to building loop. </p><p> Three modern wood pellet boilers were installed and monitored in this research. Two 25 kW boilers (PB and WPB) were installed in the end of 2014 and a 50 kW boiler (LGB) was installed in March of 2016. PB is used only for radiant floor heating and WPB is used for traditional baseboard/cast iron radiators space heating as well as providing domestic hot water (DHW) supply. LGB boiler is used for concrete slab heating. The three boiler installations provide different methods of heating and different levels of building heat demand.</p><p> This research first evaluated the performance of residential scale wood pellet boilers (25 &ndash; 50 kW) in terms of boiler operation characteristics, thermal efficiency, boiler emissions, TES tank stratification and discharge efficiency, etc. Comparisons were also made among different boilers and suggestions for improvements were made. A process dynamic simulation using VMGSim was built up based on the field monitoring data. Good agreement between the simulation and field data was found. The model was then used to size the TES tank with respect to different boiler capacities and heating demands. A system sizing algorithm was provided in the end. The results will be used to compose a guidance document for wood pellet boiler heating systems. </p>

<p> Man-made pollution is hazardous to both the environment and human health. This study attempts to develop a low-cost, biobased adsorbent for CO₂ capture and heavy metal removal. The adsorption behavior of CO₂ from air and Pb (II) from aqueous systems onto polyethylenimine (PEI) modified biochar was studied. Chemical and physical pretreatments were performed in an attempt to enhance the adsorption kinetics of biochar. FT-IR and Elemental Analysis were performed to confirm the loading of PEI onto the surface of biochar was achieved. The efficiency of the PEI modified biochar on the removal of Pb (II) from aqueous solutions was determined by Atomic Absorption Spectrometer (AAS). Alkali pretreatment of PEI modified biochar increased CO₂ capture and removal of Pb(II). This experiment introduces a new approach to air and water purification by using the combination of an amine with biochar.</p><p>

<p> In recent years a surge in research focused on the influences of water on humans. However, few have studied the effects of water on our relationship with nature, particularly to explore enduring impressions from a longitudinal perspective. Addressing these gaps, this qualitative exploratory research enlisted a case study methodology that employed multiple methods to investigate how a multi-day wilderness trip on the Tatshenshini River might affect participants&rsquo; connection to nature and position toward a sustainable lifestyle. The 12 participants were administered the Kellert Shorb Biophilic Indicator (KSBVI) questionnaire prior to the trip and reflected in journals during the experience. Six months after the trip ended a survey was administered. After 16 months, in-depth interviews were conducted. The results suggest that immersion into <i> river time</i>, an experience conceptualization that connected participants to nature&rsquo;s rhythm, generally equated with a <i>flow</i> state and a condition of <i>blue mind</i>, positively influenced their connection to nature. It appears that living water in concert with awe-inspiring encounters in the natural world enhanced and affirmed participants&rsquo; position toward a sustainable lifestyle. Furthermore, this multi-day wilderness experience seemed to inform their orientation toward sustainability. The findings suggest that further research into the lasting effects of river time and awe within these types of contexts is warranted.</p><p>

<p> Environmental sustainability is an extension of the concept of sustainability that focuses on the importance of understanding the interconnectivity between natural and socio-economic systems without compromising resource capacity. In this study, it is incorporated into a framework that applies to the sustainable development of small counties in the South Texas region of the Eagle Ford Shale. </p><p> The research involved a qualitative approach through the distribution of a questionnaire to a surveyed sample of Texas residents from Gonzales and Karnes counties. The purpose of the questionnaire was to obtain the expressed perspectives of residents regarding the impacts of shale development on their quality of life. These locations of interest were selected because of the different levels of shale development they experienced. Aspects of quality of life were analyzed as indicators of the survey responses to open and closed-ended questions. Participants described and scaled variables regarding impacts, benefits, and notable changes they experienced from the development of shale resources in their counties. Content analysis was used to obtain results relevant to developing the conceptual model for environmental sustainability proposed in this study. Findings showed that the sample of participating residents highly identified with socio-economic interests compared to environmental interests, considering that when the study was conducted shale oil and gas production was in decline as a result of fallen global energy prices. </p><p> In this study the terms sustainability and sustainable development were used interchangeably, while development was addressed in a broad sense, referring to the overall improvement of quality of life.</p><p>

<p> The purpose of this research was to explore the state of sustainability in U.S. Parks and Protected Areas (PPAs) as well as to create a tool to help measure and maintain sustainability in PPAs. The primary research question driving this research was &ldquo;What is the current state of sustainability in U.S. PPAs?&rdquo; This guiding question also addressed a sub-question, which asked, &ldquo;Can a tool be developed and validated to measure the state of sustainability in parks?&rdquo; The second research question in this project was &ldquo;Do current park managers believe the use of a sustainable parks certificate would aid ongoing efforts to uphold and maintain sustainability in their parks?&rdquo; Each research question was addressed through the creation of a survey to measure the state of sustainability through five hypothesized domains, with 55 Likert-scale-style questions and six open-ended questions addressing the certificate program. The survey opened in May 2017 and ended in October 2017. It was sent to approximately 2,645 managers across the country and included national parks and state parks in U.S. states and territories. The data showed that participants were in favor of creating a sustainable parks certificate to help them become more sustainable. A chief recommendation was to start an initiative aimed at providing an online platform for sustainability training geared specifically toward PPAs. This research project has begun the steps necessary to advance the state of sustainability in U.S. PPAs.</p>