Search results for "Wage"
showing 10 items of 731 documents
DESASS: A software tool for designing, simulating and optimising WWTPs
2008
This paper presents a very useful software tool to design, simulate and optimise wastewater treatment plants. The program is called DESASS (DEsign and Simulation of Activated Sludge Systems) and has been developed by CALAGUA research group. The mathematical model implemented is the Biological Nutrient Removal Model No.1 (BNRM1) which allows simulating the most important physical, chemical and biological processes taking place in treatment plants. DESASS calculates the performance under steady or transient state of whole treatment schemes including primary settlers, volatile fatty acid generation systems by primary sludge fermentation, activated sludge systems for biological organic matter a…
Screening pretreatment methods to enhance thermophilic anaerobic digestion of pulp and paper mill wastewater treatment secondary sludge
2013
Abstract The effect of hydrothermal (150 °C for 10 min and 70 °C for 40 min), enzymatic (Accelerase 1500, 0.07 g/g volatile solids (VS)), ultrasound (45 kHz for 30 min) and chemical pretreatments (HNO3 at pH 3 and NaOH at pH 12) alone or in combination on the chemical composition and methane yield of the pulp and paper mill secondary sludge was studied in batch assays at 55 °C. In total, 12 different pretreatment combinations were compared. Chemical analyses showed that all pretreatments except for HNO3 and ultrasound pretreatments improved the organic matter solubilization. Among the studied pretreatments, hydrothermal (150 °C, 10 min) pretreatment alone or in combination with enzymatic an…
Wastewater modification processes in a stabilization reservoir: a new mathematical model
2018
The paper presents a mathematical model for the simulation of the ecology of a wastewater stabilization reservoir (WSR). WSRs are hypertrophic aquatic systems devoted to water storage in warm countries where shortage conditions are often encountered. Several factors that affect the stabilization reservoir’s effluent quality were taken into account: hydraulics and hydrology, solar radiation, reaeration, algae, zooplankton, organic matter, pathogens, and sediment-water interactions. The model quantifies the specific influence of each factor on effluent quality, and evaluating the correlation between the different factors. State variables included in the model were: algae, dissolved oxygen, or…
Use of biological and sedimentation models for designing Peñíscola WWTP.
2004
This paper presents Peñíscola wastewater treatment plant design. Peñíscola is a tourist city in Castellón (Spain), whose population changes significantly between summer and the rest of the year. The design of the biological and settling treatment units has been confirmed by computer model simulations and provided for biological organic matter, nitrogen and phosphorus removal. Two different treatment schemes have been proposed in order to optimize the plant performance during both seasonal operations. During low-load season, the plant will be operated under extended aeration conditions, so further sludge stabilization will not be needed. During high-load season, the plant will be operated un…
New processes of the circular economy in water and wastewater treatment : Waterpro project publication
2021
This report presents results of research done in the WaterPro project New processes of the circular economy in water and wastewater treatment. In this project, water treatment solutions based on material streams produced as sidestreams or wastestreams of industrial processes or mining were researched and developed. These materials were modified for use as adsorbents or precipitation chemicals for water treatment solutions aiming to remove nutrients or metals. Materials such as paper mill sludge, slag, fly ash, jarosite, analcime, and brucite were used. Adsorption, chemical precipitation, and electrochemical precipitation were applied as water purification methods. Experiments were performed…
Current Accounts and Coordination of Wage Bargaining
2018
This study provides novel evidence on the impact of labor market institutions on current account dynamics. Our results suggest that a high degree of coordination of wage bargaining has a positive effect on the current account balance over the long run. This result is not driven entirely by wage moderation induced by centralized wage setting. We also provide robust evidence that a high degree of coordination of wage bargaining is associated with a slower current account adjustment toward its long-run equilibrium. This result seems theoretically plausible; the aggregate shocks in the exporting sector are largely driven by idiosyncratic shocks and the presence of idiosyncratic shocks increases…
Essays on current account imbalances
2017
Global current account imbalances and intra-euro area imbalances have been at the forefront of academic and policy debates for the last ten years. This thesis examines the determinants of current account balances and external adjustment. It consists of an introduction and four empirical studies. This thesis highlights the importance of institutional factors such as differences in national cultures and cross-country differences in the coordination of wage bargaining on external balances. The first study investigates the effects of deep determinants on current account balances. The point estimates are economically and statistically significant, suggesting that countries populated by Roman Cat…
Wage level or internal dispositions- what is more important in determining the satisfaction of employees on different posititions?
2016
The paper examines the mutual impact of both declared wages level and personal dispositions – core self-evaluations (Judge et al. 2003) on the perceived job and life satisfaction. Although the current consensus is that money does not guarantee happiness, a recent study by Kahneman and Deaton (2010) suggest there may be a positive money-life satisfaction relation, which is capped at a given level of income. The current study was conducted in 2015-2016 on a large sample (N=746) of Polish workers from different companies and organizational positions. The results, indicating that internal dispositions matter to a far greater extent than wages, are discussed in light of both selection and compen…
Methylophilaceae and Hyphomicrobium as target taxonomic groups in monitoring the function of methanol-fed denitrification biofilters in municipal was…
2017
Abstract Molecular monitoring of bacterial communities can explain and predict the stability of bioprocesses in varying physicochemical conditions. To study methanol-fed denitrification biofilters of municipal wastewater treatment plants, bacterial communities of two full-scale biofilters were compared through fingerprinting and sequencing of the 16S rRNA genes. Additionally, 16S rRNA gene fingerprinting was used for 10-week temporal monitoring of the bacterial community in one of the biofilters. Combining the data with previous study results, the family Methylophilaceae and genus Hyphomicrobium were determined as suitable target groups for monitoring. An increase in the relative abundance …
Microbial Community Response on Wastewater Discharge in Boreal Lake Sediments
2017
Despite high performance, municipal wastewater treatment plants (WWTPs) still discharge significant amounts of organic material and nitrogen and even microbes into the receiving water bodies, altering physico-chemical conditions and microbial functions. In this study, we examined how nitrified wastewater affects the microbiology of boreal lake sediments. Microbial community compositions were assessed with next generation sequencing of the 16S rRNA gene, and a more detailed view on nitrogen transformation processes was gained with qPCR targeting on functional genes (nirS, nirK, nosZI, nosZII, amoAarchaea, and amoAbacteria). In both of the two studied lake sites, the microbial community compo…