Ball Passage and Impeller Types Do Not Characterize the Functional Performance of a Sewage Pump

2020 ◽  
Author(s):  
David Konstantin Tilcher ◽  
Michael Pöhler ◽  
Paul Uwe Thamsen
Keyword(s):  
Energy Efficiency ◽  
System Dynamics ◽  
Functional Performance ◽  
Objective Assessment ◽  
Test Procedure ◽  
Energy Requirements ◽  
Fluid System ◽  
Dual Channel ◽  
Low Efficiency ◽  
Impeller Geometry

Abstract During the development of sewage pumps their functionality and efficiency have been continuously improved. Different impeller types have been developed; types to reduce clogging, types for associated maintenance during the various stages of the wastewater transport system, and types to increase the efficiency of the pumps. In the current market, energy requirements and efficiency play an increasingly important role. The design of pump impellers with the aim of improving efficiency may increase the susceptibility of clogging. So far there is no test describing both the energy efficiency and the wastewater pumping functionality. Operators can only describe in tenders, a desired efficiency and the indication of plausible experience with respect to the impeller geometry: the impeller shape and the ball passage. It is generally assumed that the susceptibility of clogging can be derived from the impeller shape and the ball passage (or freely passable space). Under this assumption, the vortex impeller should have the lowest susceptibility to clogging. With single and dual-channel impellers, accordingly, the largest possible ball passage points to a low susceptibility of clogging. Both, the hydraulically disadvantageous form of the vortex impeller and an enlargement of the ball passages beyond the hydraulic requirements leads to a significant reduction of efficiency. Generally, it is inferred from these circumstances that clog-free pumps are associated with low efficiency. This assumption, which is also found in the literature, requires a uniform test procedure for the objective assessment of the clogging behavior of sewage pumps. Such a test did not exist. At the Chair of fluid system dynamics, TU Berlin a test stand was developed to examine such assumptions to investigate the functionality and the clogging behavior of sewage pumps. More than 30 different wastewater pumps were tested in this procedure. The results may suggest a correlation between the susceptibility to clogging and the shape of the impeller or ball passage of various sewage pumps. Based on investigations already carried out at the Chair of fluid system dynamics, TU Berlin, the following conclusions are drawn from the measurements: • the superordinate impeller form (Vortex, Channel, etc.) gives no evidence about the susceptibility to blockages, • the ball passage does not indicate the susceptibility to blockages. From these observations it can be deduced: • a sewage pump with an appropriate efficiency may have a low susceptibility to clogging. It can therefore be concluded that the ball passage and the type of impeller are not appropriate parameters to characterize the functional performance of a sewage pump.

scholarly journals A Comparative Study of Energy Efficiency in Tumbling Mills with the Use of Relo Grinding Media

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 735
Author(s):  
Nikolay Kolev ◽  
Petar Bodurov ◽  
Vassil Genchev ◽  
Ben Simpson ◽  
Manuel G. Melero ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Test Procedure ◽  
Mining Industry ◽  
Slight Modification ◽  
Index Test ◽  
Grinding Media ◽  
Work Index ◽  
Mineral Sample ◽  
Tumbling Mills ◽  
Bond Tests

An evaluation of Relo grinding media (RGM, Reuleaux tetrahedron-shaped bodies) performance versus standard grinding media (balls) was made through a series of grinding tests, including a slight modification of the standard Bond test procedure. Standard Bond tests showed a reduction in the Bond ball mill work index (wi) of the mineral sample used in this study when using Relo grinding media. The modified Bond test procedure is based on using the standard Bond ball work index test but changing the circulating loads (350%, 250%, 150%, 100%). The comparative tests with RGM were carried out at the same number of revolutions as the grinding tests with balls at respective circulating load. The RGM charge yielded a 14% higher net undersize product than balls, which hints at improving energy efficiency and the potential for significant mining industry benefits.

Creative Introductory Test in a Remote Format: Experience of Planning Within the Framework of a Competence-Based Approach

2020 ◽  
Vol 19 (3) ◽  
pp. 93-101
Author(s):  
N.V. Tretyakova ◽  
◽  
O.E. Krayukhina ◽  
E.Zh. Shupletsova ◽  
L.E. Shmakova ◽  
...  
Keyword(s):  
Objective Assessment ◽  
Test Procedure ◽  
Educational Programs ◽  
Learning Technologies ◽  
Educational Process ◽  
Creative Work ◽  
Examination Committee ◽  
Educational Organizations ◽  
E Learning ◽  
Distance Learning Technologies

the article presents the experience of planning the content, forms, conditions and procedure for conducting entrance tests of the admission campaign of 2020 for educational programs of a creative orientation in the context of preventing the spread of a new coronavirus infection – in a remote format. This format of the introductory tests is new for educational organizations and requires detailed study. As a methodological tool for solving the problem, a competent-oriented approach was made, which made it possible to determine the content and provide for an objective assessment of special competencies that ensure the incoming success of the educational program of a creative orientation. Within the framework of this approach, it is proposed to divide the creative test procedure into two periods, allowing the applicant to do creative work offline without interaction with members of the examination committee and in real time online, with indirect (at a distance) interaction between applicants and members of the examination committee. The results of this work enrich the experience in the implementation of the educational process using e-learning and distance learning technologies and can be used during the period of intermediate certification in the implementation of educational programs of any level related to the implementation of creative work.

scholarly journals Measurement of Energy Production from Biogas: Evidence from the Wastewater Treatment Plant in Durres

2020 ◽  
Vol 5 (10) ◽  
pp. 1260-1262
Author(s):  
Stela Sefa ◽  
Tania Floqi ◽  
Julian Sefa
Keyword(s):  
Energy Efficiency ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Energy Production ◽  
Biogas Production ◽  
Treatment Plant ◽  
Electricity Consumption ◽  
Waste To Energy ◽  
Energy Requirements ◽  
Daily Consumption

The wastewater treatment plant serving the city of Durres, which is the second most populous city of Albania, employs the tertiary advanced wastewater treatment method and engages in biogas production to achieve energy efficiency. In order to empirically evaluate the plant’s energy efficiency realization, the total biogas produced and converted to electricity for daily consumption was measured during a three years period (2016 - 2018). The highest electricity produced was recorded in 2016, with a daily average of 844kWh compared to 550kWh and 370kWh in 2017 and 2018, respectively. So that the plant meets proper criteria to classify as an energy-efficient entity, 30.0 percent of its electricity consumption must be derived from biogas. Converted in kWh, the plant should generate 2,975 kWh/day. Based on the biomass and energy values measured during the study period, it is concluded that electricity supplied from biogas met 6.0 percent of the plant’s energy requirements, or one fifth of the energy-efficiency target. While the plant was successful in carrying out the full waste-to-energy production process, the electricity supplied from biogas was very low and did not fulfil the plant’s self-energy requirements.

scholarly journals ANÁLISE DE EFICIÊNCIA ENERGÉTICA EM INSTITUIÇÕES DE ENSINO SUPERIOR MULTICAMPI E UMA NOVA PROPOSTA DE ROTULAGEM AMBIENTAL

2020 ◽  
pp. 1-19
Author(s):  
Osvaldo Augusto Vasconcelos de Oliveira Lopes Da Silva ◽  
José Machado Moita Neto ◽  
Marcos Antônio Tavares Lira
Keyword(s):  
Energy Efficiency ◽  
Management Strategies ◽  
Relative Energy ◽  
Administrative Management ◽  
Environmental Labeling ◽  
Performance Indexes ◽  
Environmental Management Strategies ◽  
Low Efficiency ◽  
Environmental Labels

The expansion of Brazilian higher education institutions (HEIs) organized in multicampi structures brought a significant complexity to the academic and administrative management. In this context, environmental management strategies become quite relevant, especially when considering the low effectiveness of the Brazilian Labeling Program (BLP) for the classification of buildings in practice. The main objective of the present paper is to evaluate the BLP efficacy as applied to HEI buildings, aiming to develop a new environmental labeling model for multicampi HEIs. For this purpose, the BLP was applied to the labeling of Instituto Federal de Educação, Ciência e Tecnologia do Piauí (IFPI), employing data obtained from electricity bills between 2016 and 2018. The energy diagnosis was performed considering distinct indicators,performance indexes, levels and rankings of relative energy efficiency, from which energy efficiency labels could be developed. The results allow the verification of the low efficiency of the BLP, especially in the environmental labeling of HEIs. From the detailed analysis of bills, it is possible to develop environmental labels inspired by the BLP, resulting in a different approach. A novel type-II environmental labeling methodology is then introduced based on the breakdown of electricity bills and statistical methods.

The Environmental-adjusted Energy Efficiency of China’s Construction Industry: A Three-stage Undesirable SBM-DEA Model

2021 ◽  
Author(s):  
Yufeng Chen ◽  
Lihua Ma ◽  
Zhitao Zhu
Keyword(s):  
Energy Efficiency ◽  
Construction Industry ◽  
Building Materials ◽  
External Environment ◽  
High Energy ◽  
Management Level ◽  
Dea Model ◽  
Improve Energy Efficiency ◽  
Low Efficiency ◽  
Pillar Industry

Abstract Construction industry is a pillar industry of China's national economy but its problems of high energy consumption, high pollution and low energy efficiency is increasingly prominent. The study on the energy efficiency of construction industry is of great significance for improving development quality and achieving the goal of energy saving and emission reduction. In this paper, a three-stage undesirable SBM-DEA model was employed to measure the energy efficiency in construction industry during 2005 -2016. The CO2 directly emitted by the construction industry and indirectly emitted in the production of building materials were used as the undesirable output and the three-stage framework was employed to analyze and eliminate the influence of external environment. The empirical results showed that low efficiency of management in the construction industry is an important factor leading to the low level of energy efficiency in China’s construction industry. For the energy efficiency value before and after adjustment, the “high-high” provinces has made full use of the superior external environment by their high management level, while the “high-low” provinces needs to fully realize the potential in promoting energy efficiency of its external environment by improving its own management of construction industry. On the contrary, the “low-high” provinces need to improve the external environment to ease its restrictions on the level of management in the construction industry. Environmental factors and management level should be considered simultaneously for different provinces to improve energy efficiency of construction industry.

Energy Efficiency in Children With Myelomeningocele During Acute Use of Assistive Devices: A Pilot Study

2018 ◽  
Vol 35 (1) ◽  
pp. 57-75 ◽  
Author(s):  
Jennifer K. Sansom ◽  
Beverly D. Ulrich
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Pilot Study ◽  
Oxygen Uptake ◽  
Early Adulthood ◽  
Minimal Change ◽  
Assistive Devices ◽  
Assistive Device ◽  
Energy Requirements ◽  
Net Energy

Due to increased metabolic demands during walking, ∼50% of children with myelomeningocele transition to wheelchair use during adolescence/early adulthood. The purpose of our pilot study involving children with myelomeningocele was to determine: (a) energy expenditure needs during acute use of common assistive devices and (b) if walking poles are a feasible assistive device. Oxygen uptake was recorded for eight (5–12 years old) children in four conditions: independent, walker, crutches, and poles. Acute pole use did not significantly differ from independent walking net energy consumption or cost. Participants consumed more energy while walking with the walker than independently. Our pilot results suggest that (a) acute use of common assistive devices while walking increases energy consumption and cost versus independent and (b) poles are feasible assistive devices, resulting in slightly increased energy requirements. Poles may have provided “just enough” support with minimal change in energy requirements for our participants and, with practice, may enable children with myelomeningocele to remain community ambulators.

scholarly journals A fuzzy-rule-based packet reproduction routing for sensor networks

2018 ◽  
Vol 14 (4) ◽  
pp. 155014771877401 ◽  
Author(s):  
Jinhuan Zhang ◽  
Anfeng Liu ◽  
Peng Hu ◽  
Jun Long
Keyword(s):  
Energy Efficiency ◽  
Data Transmission ◽  
Fuzzy Inference ◽  
Network Reliability ◽  
Data Gathering ◽  
Fuzzy Rule ◽  
High Energy ◽  
Transport Delay ◽  
Reliable Routing ◽  
Low Efficiency

It is a major challenge to transfer target sensing data efficiently to sink in Internet of things. The low-efficiency data transmission can cause low quality of service. To realize the emergent detection and periodic data gathering, the sensed data should be transferred to the sink efficiently and quickly. Recently, there are many related studies. However, there are few researches taking energy efficiency, transport delay, and network reliability into comprehensive consideration. In this article, a novel adaptive green and reliable routing scheme based on a fuzzy logic system is proposed in consideration of energy efficiency, end-to-end transport delay, and network transmission reliability. The key idea of the proposed scheme is to generate different number of renewed packet copies after certain steps according to the fuzzy inference. The fuzzy inference reflects the knowledge that the nodes in the region far to the sink and with more remaining energy initiate and transmit more packet copies concurrently by multiple routing paths to ensure the success rate of data transmission, whereas less. Thus, the high energy efficiency and low latency are obtained for data collection. Our analysis and simulation results show that adaptive green and reliable routing is more superior than the existing scheme.

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