Environmental impact is a growing concern of many and work to decrease the influence on the environment are becoming more common and is in some cases even illegal for companies to disregard from. For the average person many things can be done to decrease their personal impact on to the environment such as consuming less, buying environmentally friendly goods, recycling ones garbage or buying goods that are already recycled. This study emphasizes on the subject of recycled goods since a trend of new stores has started to arise. These stores uses the basics from yard sales and flea markets but capitalize them using big scale economy.  They collect recycled goods from junkyards and through donations from companies and individuals aim to resell them. In this study a case of one of these stores called Returbutiken, located in Umeå Sweden, were acknowledged as it took the idea one step further by collecting furniture and other goods and restored them in their own carpentry. Returbutiken is an initiative made by the municipality of Umeå to recycle the goods the municipality does not need, donations from people and companies and also to collect items from the local junkyard. This also creates very cheap goods which have a much higher quality than those found at different flea markets. Thus this study was performed to investigate what motivation and what behavior the customers of this store had. Why were they shopping? Was it because of the price or was it because of their willingness to be more environmentally friendly? The behavior was researched through a comparative study through a questionnaire that was handed out at Returbutiken and compared with the answers of the same questionnaire which was answered by general people at the city of Umeå. The results show that there was a difference of behavior and attitudes between the average respondent in the city of Umeå compared to Returbutiken. People at Returbutiken were generally more committed and optimistic towards the environment than the average respondent in Umeå. The result shows that the age group of 30-45 prioritized the environment less than other age groups. This study also conducts that the general respondents in Umeå prioritized the environment less when they had a higher income.

Currently, the United States is investigating methods to close the nuclear fuel cycle and increase the use of nuclear power for electricity and cogeneration applications. Congress has called for and held hearings in an attempt to determine an appropriate path forward for reprocessing of nuclear fuel. However, each current proposed method presents a different set of attributes with regards to: Complexity, safety, wastes, and proliferation risks. This thesis provides a decision analysis methodology for approaching the reprocessing issue. The presented methodology builds on the previous work done in the 1970s. Further, current reprocessing technologies which are capable of processing the oxide fuels utilized in the majority of United States reactors are evaluated across ten attributes related to reprocessing performance. A weighted total score is provided for each reprocessing method in order to separate the technological from political or emotional issues related to selection of a process. While it is not the goal of this thesis to select a particular best technology, application of this methodology results in the selection of the COmbined EXtraction (COEX) technology when equal weighting is put on the attributes as defined. It is unlikely that a decision maker will approach this decision with equal weighting; however, actual decision maker weightings are known only to the decision makers. By altering the weightings, different technologies are selected.

The research demonstrated that an easily cultivated fungus was screened from filter materials of fresh water recycle aquaculture system. A fungus, characterized as being able to remediate multiple nitrogenous wastes, was identified as Aspergillus niger NBG5. A. niger NBG5 was developed as superior fungus through bioreactor so as to establish a nitrogenous removal system of single tank stirred tank reactor (SSTR). A. niger NBG5¡¦s remediative responses were tested under various temperatures. The experiment showed that specific nitrogen consumption rate was 0.047 g-N g-cell-1 day-1 at 30¢J which were better than nitrite nitrogen and protein nitrogen consumption. When the artificial wastes¡¦ ammonium concentration was set as 50 mg L-1, its ammonium consumption rate was 4.8 mg m-2 day-1. The ammonium consumption rate reached 0.32 mg m-2 day-1 with aquaculture wastes. The result revealed that SSTR removed nitrogen from aquaculture wastes by A. niger NBG5 and achieved a purpose of decreasing ammonium within aquaculture wastes. The research simulated ammonium variable numerals between SSTR and BSTR (the system of bi-tank stirred tank reactor). Through BSTR, regression formula with water flow rate and ammonium removal efficiency rate was y = 5.7219x-0.9616 when the ammonium concentration was set as 50 mg L-1. SSTR simulated a phenomenon¡Xthe more ammonium concentration aquaculture wastes reached, the much waste water volume of aquaculture tank it had. Based on the same requirements, a better water flow rate would be concluded through various water flow rate simulation tests. SSTR numerical simulation system could simulate ammonium production rate of fish tank to get consumption trends of ammonium concentration in fish tank and reactor. The simulation results would be able to decide later system design, water flow rate, feed timing and similar research references.

No description available.

Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 181-185).

Chloride is a deleterious ionic species in cooling water systems because it is important in promoting corrosion. Chloride can be removed from cooling water by precipitation as calcium chloroaluminate using ultra-high lime with aluminum process (UHLA). The research program was conducted to study equilibrium characteristics and kinetics of chloride removal by UHLA process, study interactions between chloride and sulfate or silica, and develop a model for multicomponent removal by UHLA. Kinetics of chloride removal with UHLA was investigated. Chloride removal was found to be fast and therefore, removal kinetics should not be a limitation to applying the UHLA process. Equilibrium characteristics of chloride removal with UHLA were characterized. Good chloride removal was obtained at reasonable ranges of lime and aluminum doses. However, the stoichiometry of chloride removal with UHLA deviated from the theoretical stoichiometry of calcium chloroaluminate precipitation. Equilibrium modeling of experimental data and XRD analysis of precipitated solids indicated that this deviation was due to the formation of other solid phases such as tricalcium hydroxyaluminate and tetracalcium hydroxyaluminate. Effect of pH on chloride removal was characterized. Optimum pH for maximum chloride removal was pH 12 ± 0.2. Results of equilibrium experiments at different temperatures indicated that final chloride concentrations slightly increased when water temperature increased at temperatures below 40oC. However, at temperatures above 40oC, chloride concentration substantially increased with increasing water temperature. An equilibrium model was developed to describe chemical behavior of chloride removal from recycled cooling water using UHLA. Formation of a solid solution of calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate was found to be the best mechanism to describe the chemical behavior of chloride removal with UHLA. Results of experiments that studied interactions between chloride and sulfate indicated that sulfate is preferentially removed over chloride. Final chloride concentration increased with increasing initial sulfate concentration. Silica was found to have only a small effect on chloride removal. The equilibrium model was modified in order to include sulfate and silica reactions along with chloride in UHLA process and it was able to accurately predict the chemical behavior of simultaneous removal of chloride, sulfate, and silica with UHLA.

A considerable number of modeling studies for the investigation of sulfur retention in atmospheric bubbling fluidized bed combustors have been carried out and well documented in the literature. Despite 30 years of intensive study of sulfation process in fluidized bed combustors and numerous laboratory studies, there are still many uncertainties and disagreements on the subject. In addition, modeling sulfur retention performance of Turkish lignites with high sulfur, volatile matter and ash contents has not drawn much attention to date. Recent trend in utilization of indigenous lignites in fluidized bed boilers necessitated investigation of pollutant emissions and adaptation of fluidized bed combustion technology to these lignites. In an attempt to achieve this objective, a system model, previously developed and tested for the prediction of the combustion behavior of fluidized bed combustors was extended to incorporate sulfur retention. The predictive accuracy of the model was assessed by applying it to the prediction of the behavior of METU 0.3 MWt ABFBC test rig burning indigenous lignites in their own ashes, and comparing its predictions with measurements taken on the same rig. Sulfur dioxide concentration predictions throughout the combustor were found to be in good agreement with the experimental data except for the small discrepancy between predictions and measurements in the bed section. Measurements and model predictions revealed that recyling enhances calcium utilization significantly by increasing the sorbent residence time leading to higher sulfur retention efficiencies. The system model proposed in this study proves to be a useful tool in qualitatively and quantitatively simulating the processes taking place in an atmospheric fluidized bed combustor.

With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2 reduces the selectivities for methane, enhances conversion, reduces the net CO2 produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2 FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2 FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2 is being used in the system and converting which created the concentration of the feed gas higher inside the reactor. The research has provided the best conditions for the enhanced conversion while minimizing CO2 formation. Though this research was not able to provide the optimal recycle rate it have created the path for the future research to proceed in the right direction. This reduction and utilization of CO2 will help to reduce the cost of carbon dioxide removal and saves the environment from carbon dioxide emission.

Margretelund wastewater treatment plant (WWTP) operated by the water utility Roslagsvatten AB, wasbuilt in 1956 and is located in Åkersberga town, Stockholm County, Sweden. Margretelund WWTP waslast renovated in 1999, and has been operated with the same physical, chemical, and biological processessince then. Due to issues with increased phosphorus emissions connected to increased concentration ofeffluent total suspended solids (TSS), Roslagsvatten would like to optimize the operation of their dissolvedair flotation (DAF) process and the author was tasked to conduct a study about the subject. The specificaim of the study was to propose one method for optimization with available means to reduce effluentTSS concentration during high flow rates for the present DAF process at Margretelund WWTP.Achieving the aim required an historical analysis of Margretelund WWTP’s DAF process and aninvestigation of the effect influent flow rate and effluent recycle rate (ERR) had on effluent TSSconcentration. The increase of effluent TSS was believed to be caused by increased flow rates frominfiltration and inflow (recorded to 32% of total volume the year 2020) affecting the dissolved air flotation(DAF) process.The literature study design parameters for a dissolved air flotation process, specifically the recycle flowpressurization configuration, generated information about which parameters to take into considerationwhen optimizing a DAF unit. Analysis of historic effluent measurements at Margretelund showed that42% of all samples analysed between January 2015 – January 2021 were below 10 mg/l TSS. Eachhistorical increase of surface load has brought a decreased effluent recycle rate (ERR) and consequentlyan increasing percentage of samples exceeding 10 mg/l. A Pearson correlation presented a negativecorrelation with both ERR and surface load in relation to effluent TSS concentration. This resulted inthe selection of the experimental factors ERR and surface load to be investigated in this study.Margretelunds WWTP’s DAF design of ERR being 10-15% and the design surface load of 4 m/h wasthe base values for the experimental runs. Increases of ERR percentage was done during the experimentfor four different surface loads (2.5, 4, 5 and 6 m/h), with five steps between 15% up to 35% ERR inone of the three parallel DAF units in Margretelund WWTP. TSS in the effluent was constantlymonitored using a TSS sensor. Influent TSS was measured at Roslagsvatten’s accredited laboratory in a24h composite sample with 1 hour for each sub-sample.The results showed that both the highest and the lowest ERR settings tested provided the lowest averageeffluent TSS concentrations. However, a decreased surface load was found to lower effluent TSSconcentration and ERR providing only minor differences within each surface load. Largest surface loadpossible was found to be 5 m/h, for an ERR of 15 or 35%. Surface load less than 5 m/h provided aconcentration under 10 mg/l for all ERR setting. / Margretelund avloppsreningsverk (ARV) placerat i Åkersberga, Stockholms län, byggdes 1956 och drivs av Roslagsvatten AB. Margretelund ARV har sedan 1956 renoverats vid två tillfällen senast 1999. Samma reningsprocess för fysisk, kemisk och biologisk rening har använts sedan senaste renoveringen. Roslagsvatten har haft problem med oönskat tillskottsvatten (motsvarade 32% av total volym 2020) som har påverkat deras flotationsprocess negativt gällande rening av suspenderat material. Detta har till slut lett till förhöjda utsläppsvärden av fosfor som finns bundet i det suspenderade materialet. Denna studie har utförts av författaren på efterfrågan av Roslagsvatten, med syfte att presentera optimeringsåtgärder till styrning av flotationsprocessen vid höga flöden. För att uppnå målet med studien gjordes en historisk analys av Margretelunds flotationsprocess samt undersökningar om hur variationer i inkommande flöde samt recirkuleringsgrad har påverkat koncentration av utgående suspenderat material.Teori undersöktes och information insamlades angående designparametrar gällande optimering av flotationsprocesser, mer specifikt en flotationsprocess med recirkulerat trycksatt flöde för avskiljning av susp. Analys av historiska utsläppsvärden från Margretelund ARV’s flotationsprocess visade på att 42% av proverna analyserade mellan januari 2015-januari 2021 låg under 10 mg/l för utgående suspenderat material. Varje historisk ökning av ytbelastning påvisade en minskande recirkuleringsgrad samt en ökande andel prover som översteg koncentrationen 10 mg/l. Utifrån en Pearson korrelation visades en negativ korrelationen för både ytbelastning och recirkulationsgrad gentemot koncentration av utgående suspenderat material. Både recirkuleringsgrad och ytbelastning valdes därför till denna studies experimentella faktorer. Flotationsprocessen på Margretelund ARV’s var designad för en recirkuleringsgrad på 10–15% vid ytbelastning på 4 m/h, och valdes som basvärde för experimentet. Fem olika grader av recirkulation testades för fyra olika ytbelastningar (2.5, 4, 5 och 6 m/h) i intervallet 15–35% i en av tre parallella flotations bassänger på Margretelund ARV. Koncentration utgående suspenderat material mättes kontinuerligt med en sensor. Inkommande koncentration bestämdes genom ett dygnsprov som analyserades av Roslagsvattens ackrediterade laboratorium.Ett resultat från experimenten var att både den högsta och lägsta inställningen av recirkuleringsgrad visade de lägsta medelvärdena för utgående koncentration av suspenderat material. Dock, visade resultaten att en minskande ytbelastning resulterade i lägre koncentrationer av utgående suspenderat material. Vidare sågs att recirkuleringsgraden enbart hade en låg påverkan på koncentrationerna för varje ytbelastning. Den högsta möjliga ytbelastningen utan att överstiga 10 mg/l visades vara 5 m/h med recirkuleringsgraderna 15% och 35%.

The purpose of this report was to investigate why insulation containing chlorofluorocarbon (CFC) is not always recycled correctly and examine if the supervision carried out by municipalities is enough to discourage erroneous handling. Additionally the purpose was to propose actions leading to that more insulation containing CFC is recycled and that municipalities can improve their supervision. The method used was a qualitative study where one questionnaire survey was sent to Swedish municipalities and one to demolition contractors. The results from the survey shows that 70 % of municipalities rarely carry out inspections on known demolition sites. This is mainly due to lack of resources but also due to not being aware of current demolition objects. Awareness is a primary condition for inspections. Often smaller municipalities are better informed which can be a consequence of better local knowledge. The survey shows that the material inventory, which is to take place before the application for demolition is filed, often is of a poor standard and lacks sampling for CFC. Lack of knowledge is pointed out as the main reason for incorrect handling of the material. Another reason is economy since identifying and taking care of hazardous waste is expensive. The level of knowledge needs to be increased among all affected parts and one way of doing so is to improve the cooperation and communication between different parts of the municipality so that more inspections can be conducted.