Evaluating diffuse and point source phosphorus inputs to streams in a cold climate region using a load apportionment model

2020 ◽  
Author(s):  
K.J. Rattan ◽  
M.J. Bowes ◽  
A.G. Yates ◽  
J.M. Culp ◽  
P.A. Chambers
Keyword(s):  
Point Source ◽  
Cold Climate ◽  
Climate Region

Impacts of Cold Climate Environmental Conditions on a Riser System Design and Installation

2015 ◽  
Author(s):  
Adekunle Peter Orimolade ◽  
Ove Tobias Gudmestad
Keyword(s):  
Environmental Conditions ◽  
Oil And Gas ◽  
Barents Sea ◽  
Research Work ◽  
Cold Climate ◽  
Field Development ◽  
Climate Region ◽  
Probability Of Occurrence ◽  
The Barents Sea ◽  
Development Concept

Interests in exploration and production of oil and gas in cold climate areas has increased in recent times. This can be attributed to the continual depletion of reserves in mature fields, and recent discoveries of large quantities of oil and gas in the cold climate region, including the more recent discovery of the Alta Reservoir, in the Barents Sea. However, marine operations in this region are faced with challenges resulting from its arctic conditions. Knowledge of the physical environment is important in designing offshore structures, and in planning, and executing marine operations. Selection of a suitable field development concept may be influenced by the probability of occurrence of rare events, such as drifting icebergs. Furthermore, occurrence of mesoscale phenomenon such as polar low pressures may adversely affect planned marine operations. In addition, uncertainties in weather forecasting will reflect on the available weather window to perform installation and interventions works. This paper presents some of the challenges in designing and planning for marine operations in the cold climate region. A possible field development concept for the open water areas of the Norwegian sector of the Barents Sea is discussed. The current research work considers the need for further assessment of the probability of occurrence of drifting icebergs as of importance when selecting field development concept. The Floating Production Storage and Offloading (FPSO) is proposed, and this should be designed with an internal turret system that can be disconnected and reconnected. Some of the challenges associated with riser systems design when considering a turret system with the capability to disconnect and reconnect are discussed. This paper also propose the use of ensemble forecasts as an alternative to the use of alpha factors to estimate operational weather window when planning for marine operations in the Barents Sea. The unpredictability nature of the environmental conditions, especially in the early winter is considered a challenge to marine operations.

scholarly journals An Approach to Improve Energy and Cost Performance of a Social Housing Archetype in Cold Climate Region

2019 ◽  
Vol 111 ◽  
pp. 03065
Author(s):  
Yiğit Yılmaz ◽  
Burcu Çiğdem Yılmaz
Keyword(s):  
Life Cycle ◽  
Physical Properties ◽  
Social Housing ◽  
Life Cycle Cost ◽  
Energy Performance ◽  
Cold Climate ◽  
Temperate Climate ◽  
Base Case ◽  
Climate Region ◽  
Thermo Physical Properties

The importance of building energy performance has been substantially increasing in the last decades due to the global warming. Therefore, buildings within the existing stock and the new buildings are encouraged to achieve the energy performance restrictions and efficiency levels. In this context, a social housing archetype (Harct), which is constructed in each climate region of Turkey with a common design approach for temperate climate region, is evaluated as a base case to improve the energy performance for the cold climate region by the optimization of the life cycle cost (LCC). It is, namely, aimed to not only improve the energy performance of the archetype but also to ensure optimal cost efficiency as significant criterion. It is focused to optimize the façades of the Harct in terms of window width, and optic and thermo-physical properties of the façade with determining the efficient insulation thickness level for exterior walls and efficient glazing types for windows. Firstly, façade design is analysed to find out the minimum and maximum windows’ widths to achieve the optimal window sizes. Secondly, optic and thermo-physical properties and cost data of the opaque and transparent façade elements have been designated among the market products in accordance with the current regulations. Energy model of the building has been run by Energy Plus simulation tool, in order to integrate it with GenOpt for optimization. Optimization was performed to carry out efficient frontier cases. The results were evaluated from life cycle cost (LCC) and energy efficiency point of view to highlight the cost optimal point

scholarly journals Sensitive Analysis for the Efficiency of a Parabolic Trough Solar Collector Based on Orthogonal Experiment

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaoyan Liu ◽  
Jing Huang ◽  
Qianjun Mao
Keyword(s):  
Thermal Efficiency ◽  
Solar Collector ◽  
Orthogonal Experiment ◽  
Cold Climate ◽  
Inlet Temperature ◽  
Outlet Temperature ◽  
Parabolic Trough ◽  
Pipe Length ◽  
Climate Region ◽  
Parabolic Trough Solar Collector

A multitude of the researches focus on the factors of the thermal efficiency of a parabolic trough solar collector, that is, the optical-thermal efficiency. However, it is limited to a single or double factors for available system. The aim of this paper is to investigate the multifactors effect on the system’s efficiency in cold climate region. Taking climatic performance into account, an average outlet temperature of LS-2 collector has been simulated successfully by coupling SolTrace software with CFD software. Effects of different factors on instantaneous efficiency have been determined by orthogonal experiment and single factor experiment. After that, the influence degree of different factors on the collector instantaneous efficiency is obtained clearly. The results show that the order of effect extent for average maximal deviation of each factor is inlet temperature, solar radiation intensity, diameter, flow rate, condensation area, pipe length, and ambient temperature. The encouraging results will provide a reference for the exploitation and utilization of parabolic trough solar collector in cold climate region.

Hybrid activated sludge/biofilm process for the treatment of municipal wastewater in a cold climate region: a case study

2011 ◽  
Vol 63 (6) ◽  
pp. 1121-1129 ◽  
Author(s):  
Daniele Di Trapani ◽  
Magnus Christensso ◽  
Hallvard Ødegaard
Keyword(s):  
Activated Sludge ◽  
Low Temperatures ◽  
Biofilm Reactor ◽  
Cold Climate ◽  
Hybrid Process ◽  
Climate Region ◽  
Conventional Activated Sludge ◽  
Experimental Campaign ◽  
Suspended Biomass ◽  
Biofilm Process

A hybrid activated sludge/biofilm process was investigated for wastewater treatment in a cold climate region. This process, which contains both suspended biomass and biofilm, usually referred as IFAS process, is created by introducing plastic elements as biofilm carrier media into a conventional activated sludge reactor. In the present study, a hybrid process, composed of an activated sludge and a moving bed biofilm reactor was used. The aim of this paper has been to investigate the performances of a hybrid process, and in particular to gain insight the nitrification process, when operated at relatively low MLSS SRT and low temperatures. The results of a pilot-scale study carried out at the Department of Hydraulic and Environmental Engineering at the Norwegian University of Science and Technology in Trondheim are presented. The experimental campaign was divided into two periods. The pilot plant was first operated with a constant HRT of 4.5 hours, while in the second period the influent flow was increased so that HRT was 3.5 hours. The average temperature was near 11.5°C in the overall experimental campaign. The average mixed liquor SRT was 5.7 days. Batch tests on both carriers and suspended biomass were performed in order to evaluate the nitrification rate of the two different biomasses. The results demonstrated that this kind of reactor can efficiently be used for the upgrading of conventional activated sludge plant for achieving year-round nitrification, also in presence of low temperatures, and without the need of additional volumes.

Sign in / Sign up

Export Citation Format

Share Document