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A Novel Process Design for Enhanced Biogas Production from Poultry Manure Using a Solar Water Heating System
No full textwastewater engineering, anaerobic digestion, solar assisted methane production, renewable energy, thermophilic conditions, poultry manure, anaerobic composting, pathogens removal, fertilizer, zero waste conceptThis paper analysis the enhancement of biogas production from poultry manure using a small
scale anaerobic digester assisted by a solar water heating system in a Palestinian poultry farm.
The farm, located in Ramallah district, with a total area of 140 m2 and accommodating around
1800 birds every 50 days produces annually about 6.57 tons (18 kg/day). An anaerobic
digester with a design volume of 0.5 m3 and a working capacity of a 0.3 m3 was fed by poultry
manure (total solids: 20%, C:N ratio: 32:1) in a continuous mode. A solar water heating system
circulated water within the digester to enhance the anaerobic digestion process. The daily
biogas yield ranged from 80 to 300 L and the methane content of the biogas ranged between
46% and 66%. As substitute to natural gas, the biogas with heat generated of 777 MJ was
directly used for onfarm heating purposes during the study period. Digester monitoring during
the winter period revealed that biogas production rate increased by 33% and the temperature
increased by 50% by using solar system. The fresh anaerobically digested slurry showed a
nutrient rich fertilizer (NPK ratio of 1:1.3:1.3). Solar drying tank enhanced the removal of fecal
pathogens (F. streptococcus) up to 3 log10. The economic profitability is expected to increase,
making the capital investment worthwhile to farmers as of free-cost feed.Faculty of Graduate Studies, Birzeit Universit
The inverse problem in convex optimization with linear constraints
No full textIn this paper, we solve an inverse problem arising in convex optimization. We consider a maximization problem under m linear constraints. We characterize the solutions of this kind of problems. More precisely, we give necessary and sufficient conditions for a given function in Rn to be the solution of a multi-constraint maximization problem. The conditions we give here extend well-known results in microeconomic theor
Stability and removal of Atorvastatin, Rosuvastatin and Simvastatin from wastewater
No full textAtorvastatin (ATO), Rosuvastatin (RST) and Simvastatin (SIM) are commonly used drugs that
belong to the statin family (lowering human blood cholesterol levels) and have been detected as
contaminants in natural waters. Stability and removal of ATO, RST and SIM from spiked wastewater produced at Al-Quds University Campus were investigated. All three statins were
found to undergo degradation in wastewater (activated sludge). The degradation reactions of the
three drugs in wastewater at room temperature follow first order kinetics with rate constants of
2.2 x 10-7 s-1(ATO), 1.8 x 10-7s-1 (RST) and 1.8 x 10-6 s-1 (SIM), which are larger than those
obtained in pure water under the same conditions, 1.9x 10-8 s-1 (ATO), 2.2x 10-8s-1 (RST) and 6.2
x 10-7 s-1 (SIM). Degradation products were identified by LC-MS and LC/MS/MS. The overall
performance of the wastewater treatment plant (WWTP) installed in Al-Quds University Campus
towards the removal of these drugs was assessed showing that more than 90% of spiked ATO,
RST and SIM were removed. In order to evaluate the efficiency of alternative removal methods
to replace ultra-filtration membranes, adsorption isotherms for the three statins were investigated
using both activated carbon and clay-micelle complex as adsorbents. The batch adsorption
isotherms for the three statins were found to fit Langmuir equation, with larger number of
adsorption sites and binding affinity for micelle-clay composite compared to activated carbon
and filtration experiments of the three statins and their corresponding metabolites demonstrated a
more efficient removal by micelle-clay filter
Communication Time in Extreme ProgrammingTeams: A Controlled Case Study
No full textSoftware development is a team-centered activity. However, there are a number of factors that affect a team’s productivity. Thus, understanding the team dynamics and the different factors that influence their working is essential to improving their productivity. One such key factor is the amount of time a team spends on communicating to completing their tasks. This paper reports on a small scale case study, of (eight participants in) four student groups, using extreme programming. The study was conducted in a controlled environment to study the factors that may affect a team communication time, during the implementation phase. We found communication time between team members of the same gender is the longest. However, forming a team with relatively equal experience and including a well documented pre-training reduces the communication time significantl
القدس في الاستراتيجية الاسرائيلية
No full textالقدس في الاستراتيجية اليهودية الصهيونية - الإسرائيلية من الطبيعي أن تكون الاستراتيجية اليهودية الصهيونية واستراتيجية كيانها إسرائيل متناغمتين تماما ومتطابقتين كليا مع ] منطلقاتها الروحية والفكرية وأهدافهما السياسية، أهمها "إعادة بناء الدولة اليهودية وعاصمتها القدس"، وانتزاع اعتراف دول العالم بضمانة دولية مؤسسة على القانون الدولي، ومواثيق مؤسسات الشرعية الدولية القائمة آنذاك. لذا فان الاستراتيجية دورا محوريا في إنجاز مهام كل اليهودية الصهيونية في سعيها لإقامة كيانها إسرائيل قد مرت بمراحل عديدة لعبت القدس .مرحلة وبخاصة تلك التي شهدت ولادة الكيان الصهيوني كنواة للدولة اليهودية التوراتي
Spring Water Qualitative Assessment in Mountainous Areas, Case Study: Soreq Catchment/Ramallah/West Bank
No full textGeosciences and Earth Sciences
Jebreen,Hassan
