efficiency. By measurements of total odour strength in a treatment plant the ED values pointed out the sludge press and dewatering process as the predominant odour sources of the plant. In the venting air from this position extremely high ED values were recorded. This air was led through a carbon filter for odour reduction. Olfactometric measurements at the filter revealed poor odour reducing efficiency. It was observed that odour compounds were not destroyed in the filter. They only restrained until the carbon became saturated, and thereafter evaporated into the outlet air contributing to the odour strength. The filter capacity was obviously too small for the heavy load. Attempts to reduce the odour strength before the filter did not succeed, until the air was led through a container filled with saturated lime slurry (pH = 12-14). The slurry was part of a precipitation process in the plant. Dispersion in the alkaline slurry extensively reduced the odour strength of the air, resulting in sufficient capacity of the carbon filter also when handling heavy loads of sewage sludge. Since then the carbon filter has worked well, within the limitation of such filters in general. Neither is it observed signs indicating reduced precipitation properties of the lime slurry. Measurements of total odour strength in combustion processes imply sampling challenges. Beside the chemical scrubber process, combustion of odorous air is the best odour reducing method. The disadvantage of this process is the high energy costs. Treatment at apropriate conditions, however, will destroy the odorous compounds extensively. Temperatures about 850 C and contact time up to 3 seconds are reported (2,3). Olfactometric measurements in combustion processes involve certain sampling problems caused by the temperature difference between inlet and outlet. The humidity of outlet air must also be taken into consideration. Problems may occur when hot outlet air is sampled at low temperatures. In most such cases sampling is impossible without special arrangements. Such conditions are present during odour measurements in fish meal plants with combustion as the odour reducing method. The largest problem turned out to be the temperature differences between outlet air (85-220 C) and outdoor temperatures (0-15 C), causing condensation. The dew point of the outlet air was calculated, and experiments were carried out with dilution of the outlet air to prevent condensation in the sampling bags. Condensation was prevented by diluting the outlet air 5-150 times with dry, purified N gas. Comparison of N -diluted and undiluted samples revealed large differences in ED value. In samples demanding a high degree of dilution to prevent condensation, the measured odour strength was up to 5 times higher than in the undiluted corresponding samples. Samples demanding less dilution showed less deviating results. 4. CONCLUSIONS In the attempt to minimize odour emission, olfactometric measurements of total odour strength give useful informations about the odour reducing efficiency of different processes as a function of parameters like dosage of chemicals in scrubbers, humidity and temperature in packed filters, flow rates, etc. Olfactometric measurements also point out the main odour sources of the plant. From a set of olfactometric data combined with other essential

1986 ◽  
pp. 98-98
Keyword(s):  
Treatment Plant ◽  
High Energy ◽  
Dew Point ◽  
Precipitation Process ◽  
Heavy Load ◽  
Heavy Loads ◽  
Combustion Processes ◽  
Sampling Problems ◽  
High Degree ◽  
Carbon Filter

EVALUATION OF BIOMETHANE YIELDS FROM HIGH-ENERGY ORGANIC WASTE AND SEWAGE SLUDGE: A PILOT STUDY FOR A WASTEWATER TREATMENT PLANT

2019 ◽  
Vol 18 (9) ◽  
pp. 2023-2034 ◽  
Author(s):  
Agnieszka A. Pilarska ◽  
Krzysztof Pilarski ◽  
Boguslawa Waliszewska ◽  
Magdalena Zborowska ◽  
Kamil Witaszek ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Pilot Study ◽  
Sewage Sludge ◽  
Wastewater Treatment Plant ◽  
Organic Waste ◽  
Treatment Plant ◽  
High Energy

scholarly journals Automated Computation of One-Loop Amplitudes

2018 ◽  
Vol 68 (1) ◽  
pp. 291-312 ◽  
Author(s):  
Celine Degrande ◽  
Valentin Hirschi ◽  
Olivier Mattelaer
Keyword(s):  
High Energy Physics ◽  
Expert Knowledge ◽  
Hadron Collider ◽  
High Energy ◽  
Hadron Colliders ◽  
Collider Phenomenology ◽  
Physics Community ◽  
High Degree ◽  
Energy Physics ◽  
Loop Amplitudes

The automation of one-loop amplitudes plays a key role in addressing several computational challenges for hadron collider phenomenology: They are needed for simulations including next-to-leading-order corrections, which can be large at hadron colliders. They also allow the exact computation of loop-induced processes. A high degree of automation has now been achieved in public codes that do not require expert knowledge and can be widely used in the high-energy physics community. In this article, we review many of the methods and tools used for the different steps of automated one-loop amplitude calculations: renormalization of the Lagrangian, derivation and evaluation of the amplitude, its decomposition onto a basis of scalar integrals and their subsequent evaluation, as well as computation of the rational terms.

scholarly journals Политермический разрез SnAs–P тройной системы Sn–As–P

2019 ◽  
Vol 21 (2) ◽  
pp. 287-295
Author(s):  
Tatiana P. Sushkova ◽  
Aleksandra V. Sheveljuhina ◽  
Galina V. Semenova ◽  
Elena Yu. Proskurina
Keyword(s):  
Phase Diagrams ◽  
Solid Solutions ◽  
Condensed Matter ◽  
High Energy ◽  
Potassium Ion ◽  
Dew Point ◽  
Sodium Ion ◽  
P System ◽  
Sodium Ion Batteries ◽  
Tin Phosphide

Проведено исследование фазовых равновесий в тройной системе Sn–As–P в области высокой концентрации летучих компонентов. Методами рентгенофазового и дифференциального термического анализа изучены сплавы политермического разреза SnAs–P. Показано, что растворимость фосфора в моноарсениде олова в направлении этого разреза менее 0.05 мол.д. фосфора. Построена Т-х диаграмма политермического сечения SnAs–Р. Наличие на Т-х диаграмме горизонтали при температуре 827±2 К соответствует реализации в системе Sn–As–P нонвариантного перитектического равновесия L + (d) ↔ b + g , где (d), b и g – трехкомпонентные твердые растворы на основе As1-xPx, SnAs и SnP3 соответственно     REFERENCES Zhang W., Mao J., Li S., Chen Z., Guo Z. Phosphorus-Based Alloy Materials for Advanced Potassium-Ion Battery Anode // Am. Chem. Soc., 2017, v. 139(9), pp. 3316–3319. https://doi.org/10.1021/jacs.6b12185 Liu S., Zhang H., Xu L., Ma L., Chen X. Solvothermal preparation of tin phosphide as a long-life anode for advanced lithium and sodium ion batteries // of Power Sources, 2016, v. 304, pp. 346–353. https://doi.org/10.1016/j.jpowsour.2015.11.056 Zhang W., Pang W., Sencadas V., Guo Z. Understanding High-Energy-Density Sn4P3 Anodes for Potassium-Ion Batteries // Joule, 2018, v. 2(8), pp. 1534–1547. https://doi.org/10.1016/j.joule.2018.04022 Lan D., Wang W., Shi L., Huang Y., Hu L., Li Q. Phase pure Sn4P3 nanotops by solution-liquid-solid growth for anode application in sodium ion batteries // Mater. Chem. A, 2017, v. 5, pp. 5791–5796. https://doi.org/10.1039/C6TA10685D Mogensen R., Maibach J., Naylor A. J., Younesi R. Capacity fading mechanism of tin phosphide anodes in sodium-ion batteries // Dalton Trans., 2018, v. 47, pp. 10752–10758. https://doi.org/10.1039/c8dt01068d Kamali A. R., Fray D. J. Tin-based materials as advanced anode materials for lithium ion batteries: a review // Adv. Mater. Sci., 2011, v. 27, pp. 14–24. URL: http://194.226.210.10/e-journals/RAMS/no12711/kamali.pdf Kovnir K. A., Kolen’ko Y. V., Baranov A. I., Neira I. S., Sobolev A. V., Yoshimura M., Presniakov I. A., Shevelkov A. V. Sn4As3 revisited: Solvothermal synthesis and crystal and electronic structure // Journal of Solid State Chemistry, 2009, v. 182(5), pp. 630–639. https://doi.org/10.1016/j.jssc.2008.12.007 Semenova G. V., Kononova E. Yu., Sushkova T. P. Polythermal section Sn4P3 – Sn4As3 // Russian J. of Inorganic Chemistry, 2013, v. 58 (9), pp. 1242–1245. https://doi.org/10.7868/S0044457X13090201 Sushkova T. P, Semenova G. V., Naumov A. V., Proskurina E. Yu. Solid solutions in the system Sn-As-P // Bulletin of VSU. Series: Chemistry. Biology. Pharmacy, 2017, v. 3, pp. 30–36. URL: http://www. vestnik.vsu.ru/pdf/chembio/2017/03/2017-03-05.pdf Semenova G. V., Sushkova T. P, Tarasova L. A., Proskurina E. Yu. Phase equilibria in a Sn-As-P system with a tin concentration less than 50 mol. % // Condensed Matter and Interphases, 2017, v. 19(3), pp. 408–416. https://doi.org/10.17308/kcmf.2017.19/218 Semenova G. V., Sushkova T. P., Zinchenko E. N., Yakunin S. V. Solubility of phosphorus in tin monoarsenide // Condensed Matter and Interphases, 2018, v. 20(4), pp. 644-649. https://doi.org/10.17308/kcmf.2018.20/639 Semenova G. V., Goncharov E. G. Solid Solutions Involving Elements of the Fifth Group. – Мoscow, MFTI Publ., 2000, 160 p. (in Russ.) Okamoto H. Phase diagrams for binary alloys, Second Edition. Materials Park, OH.: ASM International, 2010, 810 р. URL: https://www.asminternational. org/...pdf/c36eeb4e-d6ec-4804-b319-e5b0600ea65d Shirotani , Shiba S., Takemura K., Shimomura О., Yagi Т. Pressure-induced phase transitions of phosphorus-arsenic alloys // Physica B: Condensed Matter, 1993, v. 190, pp. 169–176.  https://doi.org/10.1016/0921-4526(93)90462-F Arita M., Kamo K. Measurement of vapor pressure of phosphorus over Sn-P alloys by dew point method // Jpn. Inst. Met., 1985, v. 26(4), pp. 242–250. https://doi.org/10.2320/matertrans1960.26.242 Zavrazhnov A. Yu., Semenova G. V., Proskurina E. Yu., Sushkova T. P. Phase diagram of the Sn–P system // Thermal Analysis and Calorimetry, 2018, v. 134(1), pp. 475–481. https://doi.orgh/10.1007/s10973-018-7123-0 Gokcen N. A. The As-Sn (Arsenic-Tin) system // Bulletin of alloy phase diagrams, 1990, v. 11(3), pp. 271–278. https://doi.org/10.1007/BF03029298

scholarly journals Identification allergen Cladosporium spores concentration in the ambient of Ahvaz wastewater treatment plant and their relationship with meteorological variables, Ahvaz, Iran

2020 ◽  
Author(s):  
Nastaran Talepour ◽  
Mohammad Sadegh Hassanvand ◽  
Effat Abbasi-Montazeri ◽  
Seyed Mahmoud Latifi ◽  
Neamat Jaafarzadeh Haghighi Fard
Keyword(s):  
Wastewater Treatment ◽  
Wind Speed ◽  
Meteorological Parameters ◽  
Treatment Plant ◽  
Allergic Diseases ◽  
Airborne Fungi ◽  
Air Pressure ◽  
Dew Point ◽  
Uv Index ◽  
Ultraviolet Index

Introduction: Airborne Cladosporium spores in different regions of the world are known as the main cause of allergic diseases. This study aimed to identify the Cladosporium species airborne fungi in Ahvaz wastewater treat- ment plant area and its adjacent places and check the effect of some meteoro- logical parameters on their emissions. Materials and methods: Cladosporium spores were cultured on Sabouraud`s dextrose agar (SDA) medium in both cold and warm seasons. The passive sampling method was performed and after incubation, colonies were counted as CFU/Plate/h. Then, according to the macroscopic and microscopic charac- teristics of the genus, the fungal was studied. The meteorological parameters including temperature, humidity, air pressure, dew point, wind speed, and ultraviolet index were measured. Results: At least, 3358 colonies were counted. 1433 colonies were related  to the Cladosporium species. The amount of Cladosporium in indoor air was 46% of the total Cladosporium. The average of meteorological parameters includes temperature, humidity, air pressure, dew point, wind speed and UV index during the study were 27.8 °C, 32.9%, 548.7 °Kpa, 3.6°, 9.1 km / h and 3.9 respectively. 42.6% of the total number of colonies was related to the Cladosporium species. Cladospiromes had a direct correlation with the dew point, temperature, humidity, air pressure, wind speed, and ultraviolet index (Pvalue<0.05). Primary sludge dewatering has the greatest role in the Cladospo- rium spores emission. Conclusion: Considering the importance of Cladosporium spores in the ap- pearance of allergic diseases, and given that wastewater treatment workers spend most of their time outside, observing health and preventive measures is necessary in this regard.

scholarly journals Modelling the bioenergy potential of municipal wastewater treatment plants

2018 ◽  
Vol 77 (11) ◽  
pp. 2613-2623 ◽  
Author(s):  
Kerstin Schopf ◽  
Johannes Judex ◽  
Bernhard Schmid ◽  
Thomas Kienberger
Keyword(s):  
Wastewater Treatment ◽  
Sewage Sludge ◽  
Energy Recovery ◽  
Municipal Wastewater ◽  
Energy Content ◽  
Treatment Plant ◽  
High Energy ◽  
Recovery Efficiency ◽  
Municipal Wastewater Treatment ◽  
Self Sufficiency

Abstract A municipal wastewater treatment plant accounts for a large portion of the total energy consumption of a municipality. Besides their high energy demand, the plants also display a significant bioenergy potential. This is due to the utilisation of the energy content of digester gas and sewage sludge if there exist suitable units. To maximise the energy recovery efficiency of wastewater treatment systems (WWTS), it is important to analyse the amount of digester gas and sludge produced in different types of plants. Therefore, the present paper deals with designing a tool to answer the following research questions: Which bioenergy potentials occur in different plant types? Which mass and energy flows are related to the specific potentials? Which utilisation processes for the potentials can lead to a high energy recovery efficiency of WWTS? Preliminary analyses with the designed tool were focused on estimating the level of electric and thermal energy self-sufficiency of different plant configuration scenarios including or excluding digester gas and/or sludge utilisation units. First results based on the level of self-sufficiency and associated energy and disposal costs show that a digester gas and sewage sludge utilisation should be considered when designing future WWTS.

An Overview of Different Indirect and Semi-Indirect Evaporative Cooling System for Study Potency of Nanopore Skinless Bamboo as An Evaporative Cooling New Porous Material

2021 ◽  
Vol 79 (2) ◽  
pp. 123-130
Author(s):  
I Nyoman Suprapta Winaya ◽  
Hendra Wijaksana ◽  
Made Sucipta ◽  
Ainul Ghurri
Keyword(s):  
Energy Consumption ◽  
Porous Material ◽  
Cooling System ◽  
Evaporative Cooling ◽  
Temperature Drop ◽  
High Energy ◽  
Dew Point ◽  
Air Cooling ◽  
Evaporative Cooling System ◽  
Indirect Evaporative Cooling

The high energy consumption of compressor based cooling system has prompted the researchers to study and develop non-compressor based cooling system that less energy consumption, less environment damaging but still has high enough cooling performances. Indirect and semi indirect evaporative cooling system is the feasible non-compressor based cooling systems that can reach the cooling performance required. This two evaporative cooling system has some different in construction, porous material used, airflow scheme and secondary air cooling method used for various applications. This paper would report the cooling performances achieved by those two cooling system in terms of cooling efficiency, cooling capacity, wet bulb effectiveness, dew point effectiveness, and temperature drop. Porous material used in indirect and semi-indirect evaporative cooling would be highlighted in terms of their type, size, thickness and any other feature. The introduction of nanopore skinless bamboo potency as a new porous material for either indirect or semi-indirect evaporative cooling would be described. In the future study of nanopore skinless bamboo, a surface morphology and several hygrothermal test including sorption, water vapor transmission, thermal conductivity test would be applied, before it utilize as a new porous material for direct or semi indirect evaporative cooling.

Implementation of EU discharge guidelines at IVAR's Regional Wastewater Treatment Plant of North Jaeren, Stavanger, Norway

2001 ◽  
Vol 44 (1) ◽  
pp. 33-39 ◽  
Author(s):  
O. Tornes
Keyword(s):  
Wastewater Treatment ◽  
Feasibility Study ◽  
Chemical Treatment ◽  
Biological Treatment ◽  
Treatment Plant ◽  
Primary Treatment ◽  
Full Scale ◽  
Precipitation Process ◽  
European Economic Area ◽  
The Eu

Norway is a leading country on wastewater treatment comprising chemical precipitation processes. This is because Norwegian effluent standards to the North Sea have traditionally focused on phosphorus removal. In most cases, chemical treatment therefore has been considered to give lower investment and operating costs than biological treatment. Norwegian wastewater policy and management is based on the EU guidelines resulting from the EEA (European Economic Area) Agreement. According to the 1991 Urban Wastewater Treatment Directive, this will in most cases require secondary treatment. However, primary treatment can be accepted for plants larger than 10,000 PT with effluents to less sensitive coastal areas, if no negative environmental impacts can be proved. The main objective of the Regional Water, Sewerage and Waste Company (IVAR) is to comply with the prevailing effluent limits at lowest possible cost. During the past four years, IVAR has therefore undertaken comprehensive optimising of the precipitation process including full-scale experiments with different coagulant dosing control systems and different types of coagulants. IVAR also accomplished a feasibility study of introducing biological treatment as an alternative to chemical treatment. Under the prevailing frame conditions of discharge requirements and sludge deposit costs, it is not economically feasible to change to organic coagulants or biological treatment. This conclusion might have to be altered later resulting from the implementation of new EU regulations and increasing sludge deposit costs. This paper presents results from full-scale experiments, extracts from the feasibility study and a comparison of costs. Furthermore, the practical consequences of implementing the EU-guidelines are discussed.

ASM1 dynamic calibration and long-term validation for an intermittently aerated WWTP

2006 ◽  
Vol 53 (12) ◽  
pp. 247-256 ◽  
Author(s):  
A. Marquot ◽  
A.-E. Stricker ◽  
Y. Racault
Keyword(s):  
Treatment Plant ◽  
Simulation Software ◽  
Biological Nutrient Removal ◽  
Model Parameters ◽  
Dynamic Calibration ◽  
Biological Degradation ◽  
Data Set ◽  
Degree Of Confidence ◽  
High Degree

Activated sludge models, and ASM1 in particular, are well recognised and useful mathematical representations of the macroscopic processes involved in the biological degradation of the pollution carried by wastewater. Nevertheless, the use of these models through simulation software requires a careful methodology for their calibration (determination of the model parameters' values) and the validation step (verification with an independent data set). This paper presents the methodology and the results of dynamic calibration and validation tasks as a prior work to a modelling project for defining a reference guideline destined to French designers and operators. To reach these goals, a biological nutrient removal (BNR) wastewater treatment plant (WWTP) with intermittent aeration was selected and monitored for 2 years. Two sets of calibrated parameters are given and discussed. The results of the long-term validation task are presented through a 2-month simulation with lots of operation changes. Finally, it is concluded that, even if calibrating ASM1 with a high degree of confidence with a single set of parameters was not possible, the results of the calibration are sufficient to obtain satisfactory results over long-term dynamic simulation. However, simulating long periods reveals specific calibration issues such as the variation of the nitrification capacity due to external events.

EXPERIENCE AND PRACTICE IN CARRYING A HEAVY, UNILATERAL LOAD: FOOTPRINT EVIDENCE

2017 ◽  
Vol 17 (01) ◽  
pp. 1750022 ◽  
Author(s):  
DAVID WEBB ◽  
SARA BRATSCH
Keyword(s):  
Anterior Part ◽  
Center Of Mass ◽  
Initial Study ◽  
Ease Of Use ◽  
Human Walking ◽  
Step Width ◽  
Heavy Load ◽  
Subtle Change ◽  
Foot Placement ◽  
Heavy Loads

Although a significant amount of research has examined the biomechanical effects of carrying a load on human walking, most has focussed on fore and aft loads, or evenly balanced loads. In addition, most research on human walking no longer considers footprint analysis, despite its ease of use and its effectiveness in studies of balance. However, one project, with a small number of subjects, suggested that people carrying a heavy load in one hand (e.g., a suitcase or toolbox) make two sorts of adjustments to the placement of their feet on the substrate. The first and most obvious change is a decrease in foot angle (in-toeing) on the unloaded side. This puts the anterior part of the foot further under the center of mass when carrying a load in the contralateral hand and has been amply documented in subsequent studies. The second and more subtle change is a decrease in step width, a practice which also moves the foot on the unloaded side closer to the center of mass. However, tests subsequent to the original study did not show a consistent or significant use of this technique. This discrepancy between original and subsequent results in step width can be explained by the level of expertise which various subjects have. Experience carrying heavy loads may be required for most subjects to develop ways of accommodating loads. For this project, subjects were tested under two conditions: carrying an empty canvas bag; carrying the same bag with 21% of their body weight in it. All subjects walked on paper runners, wearing paint-soaked socks to leave footprint trails. Subjects were asked to walk once with no weights followed by three more times with weights. They were then given 10–15[Formula: see text]min of practice with the weighted bag, then asked to repeat the protocol, for a total of eight trials (two unweighted and six weighted). Foot angle and step width were measured for all trials. Results show that practice does indeed make a difference in the use of a narrower step when carrying a heavy load. Specifically, the first three weighted trials show a decrease in step width that is nonsignificant, but the last three evince a significant reduction as compared to unweighted trials. In addition, lifetime experience carrying a heavy load led to more immediate changes in foot placement. We conclude that the initial study involved subjects who already had experience carrying a unilateral heavy load and that, as with other activities, mechanically more effective movements are acquired with greater experience and practice.

Sign in / Sign up

Export Citation Format

Share Document