Selecting suitable seed sludge for anammox enrichment: Role of influent characteristics and reactor operational conditions

2022 ◽  
pp. 126719
Author(s):  
Radhika Deore ◽  
Rakesh Kumar ◽  
Mohammad Waqqas Mirza ◽  
Abid Ali Khan
2014 ◽  
Vol 955-959 ◽  
pp. 2692-2696 ◽  
Author(s):  
Li Fan Liu ◽  
Yong Wei Liao ◽  
Jie Liang ◽  
Shu Ting Lai

The characteristics such as pH, dry matter, carbon concentration, the total solid and volatile solid of kitchen wastes produced by a canteen in Guangzhou were measured. The anaerobic digestion process performances were evaluated through the examination of operational conditions like activated sludge inoculation, temperature on SS, biogas production, COD concentration and pH in the reactor. When the proportion between kitchen wastes to seed sludge inoculation was 1:1, the biogas production reached the peak at 45 °C. The kitchen waste pH decreased at the first four days then increased adversely after 4 days digestion, but COD concentration showed the opposite variation.


2013 ◽  
Vol 726-731 ◽  
pp. 2813-2817
Author(s):  
Guang Li ◽  
Jing Li ◽  
Ke Sun

The interior diversion expanded granular sludge bed was concurrently operated for 140d to study the characteristic of the granular sludge bed. The influent COD concentration varied from 2000mg/L to 22300 mg/L, hydraulic retention time was maintained constant at 24 h and the organic loading rate was changed through a change in substrate concentration. The results showed that the reactor had great COD removal efficiency. When the MLSS was 23.1g/L, the influent COD was 18890mg/L, the COD removal efficiency was 80.4%; The interior diversion EGSB could greatly improve the role of gas-dynamic, when the liquid upflow velocity was 3.55m/h, the gas production was 5.96 L/d shows higher sludge bed expansion rate than 2.77 L/d about 9.5%. During the experimental, the anaerobic sludge has the following properties: the average sludge diameter was increased from 0.41mm to 1.66mm. Observed under the scanning electronic microscopy, we found that the sludge appeared obviously granulation, the bacteria amount and species are more than seed sludge after operation of 50d. It was found that rough surface of anaerobic sludge has clear figure with being covered by mucous lamina, with visible hole or cavity on surface.


2021 ◽  
Vol 13 (19) ◽  
pp. 10490
Author(s):  
Caterina Caramuta ◽  
Giovanni Longo ◽  
Teresa Montrone ◽  
Carlo Poloni

The relevant pressure exerted on ports following the advent of globalization and containerization has contributed to transform the role of such intermodal transport facilities, increasing their complexity with reference to both performed activities and involved actors. The potential of solid hinterland connections in enhancing port competitiveness has sustained the larger embracement of the railway mode, which has proved to be a financially and environmentally sustainable solution, especially on long hauls. However, the limited residual capacity currently characterizing several railway network and nodes may threaten the accommodation of additional future traffic volumes and, thus, it requires the adoption of a coordinated strategy to more efficiently manage existing railway infrastructures, other than the realization of some new ones. In this regard, an integrated methodology has been developed to specifically model, simulate and optimize port railway processes, as part of a more complex system, imposing the maximization of capacity with the concurrent minimization of used shunting locomotives, to varying of infrastructural and operational conditions. This combination of techniques has been applied to the case study of the Port of Trieste, Italy, showing the greater influence of tracks availability over changes in the operational conditions, in terms of a shorter duration of specific administrative tasks and the employment of more shunting locomotives.


1997 ◽  
Vol 36 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Tanja Gschlößl ◽  
Ingrid Michel ◽  
Marion Heiter ◽  
Christian Nerger ◽  
Verena Rehbein

In biological wastewater treatment inorganic and organic substances are fixed and metabolized by mixed populations of microorganisms forming either activated sludge flocs or biofilms. Not only the type of wastewater but also the operational conditions promote the development of an adapted biocenosis of microorganisms with specialized enzymatic functions. Understanding the biological properties of the microorganisms, it is possible to assess the prevailing conditions in their natural environment. Regular microscopic and enzymatic investigations of activated sludge and biofilms thus improve the assessment of the stability of the processes and support troubleshooting in wastewater treatment plants. While the role of bacteria is often discussed, the importance of ciliated protozoes and metazoes for the maintenance of the stability of biofilm systems is rarely mentioned. In this paper we intend to show some new results of direct microscopic observations in different sorts of biofilm systems focussing upon ciliated protozoes and metazoes. Practical results will demonstrate the relation between enzymatic analysis, microscopic investigations and performance of biofilm systems.


2014 ◽  
Vol 16 (44) ◽  
pp. 24209-24215 ◽  
Author(s):  
Mohammednoor Altarawneh ◽  
Zhong-Tao Jiang ◽  
Bogdan Z. Dlugogorski

This study examines the structures of all plausible terminations of CuCl2 surfaces and assesses their thermodynamic stability under practical operational conditions, relevant to the role of CuCl2 as the most crucial chlorination catalyst in combustion systems.


Author(s):  
F. Taveira Pinto ◽  
F. Veloso Gomes ◽  
P. Rosa Santos ◽  
C. Guedes Soares ◽  
N. Fonseca ◽  
...  

Moored ship behavior inside harbors and, therefore, the operational and security conditions at a port terminal does not have a straightforward relationship with local environmental conditions. Due to the diversity and complexity of the phenomena involved it is important to use a methodology that combines physical model tests with numerical simulations, taking advantage of potential synergies. Results of prototype measurements are also a key element to making the validation and calibration of both physical and numerical models possible. This paper focuses on studying the behavior of moored tankers using combined methodology. Aspects related with the inclusion in the numerical models of shallow water effects, non-linear characteristics of mooring lines and fenders, the influence of harbor boundaries and viscous damping are analyzed and discussed. The role of physical modeling as a tool to address/quantify some of the conditions and to provide data for the calibration of numerical models is presented, as well as the methodology defined for the study of the operational conditions at an existing berth. This methodology includes the development of a computer vision system to measure ship motion at the port terminal (prototype). Actual operational conditions at the berth are also described in the paper.


Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6260
Author(s):  
Mia Ala-Juusela ◽  
Hassam ur Rehman ◽  
Mari Hukkalainen ◽  
Francesco Reda

Buildings account for 36% of the final energy demand and 39% of CO2 emissions worldwide. Targets for increasing the energy efficiency of buildings and reducing building related emissions is an important part of the energy policy to reach the Paris agreement within the United Nations Framework Convention on Climate Change. While nearly zero energy buildings are the new norm in the EU, the research is advancing towards positive energy buildings, which contribute to the surrounding community by providing emission-free energy. This paper suggests a definition for positive energy building and presents the framework, elements, and challenges of the concept. In a positive energy building, the annual renewable energy production in the building site exceeds the energy demand of the building. This increases two-way interactions with energy grids, requiring a broader approach compared to zero energy buildings. The role of energy flexibility grows when the share of fluctuating renewable energy increases. The presented framework is designed with balancing two important perspectives: technical and user-centric approaches. It can be accommodated to different operational conditions, regulations, and climates. Potential challenges and opportunities are also discussed, such as the present issues in the building’s balancing boundary, electric vehicle integration, and smart readiness indicators.


Author(s):  
Bogusław Pietrzak ◽  
Katarzyna Wasiak

This article attempts to systematize the institutional and operational conditions of stability and security of the banking system. The intention of the authors is to analyse some factors strongly affecting the functions and principles of two members of modern banking systems - the central bank and commercial banks. The authors start the analyses by defining stability and security of the banking system. Then point out to the role of the various segments of the financial safety net in providing conditions for stable and secure system, and determine the necessary requirements of the stabilization as demanded from the banking institutions management system. In conclusion, they define the set of requirements (institutional and operational) necessary for achieving the stability and security of the banking system


Membranes ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 66 ◽  
Author(s):  
Victoria Sanahuja-Embuena ◽  
Gabriel Khensir ◽  
Mohamed Yusuf ◽  
Mads Friis Andersen ◽  
Xuan Tung Nguyen ◽  
...  

Although forward osmosis (FO) membranes have shown great promise for many applications, there are few studies attempting to create a systematization of the testing conditions at a pilot scale for FO membrane modules. To address this issue, hollow fiber forward osmosis (HFFO) membrane modules with different performances (water flux and solute rejection) have been investigated at different operating conditions. Various draw and feed flow rates, draw solute types and concentrations, transmembrane pressures, temperatures, and operation modes have been studied using two model feed solutions—deionized water and artificial seawater. The significance of the operational conditions in the FO process was attributed to a dominant role of concentration polarization (CP) effects, where the selected draw solute and draw concentration had the biggest impact on membrane performance due to internal CP. Additionally, the rejection of the HFFO membranes using three model solutes (caffeine, niacin, and urea) were determined under both FO and reverse osmosis (RO) conditions with the same process recovery. FO rejections had an increase of 2% for caffeine, 19% for niacin, and 740% for urea compared to the RO rejections. Overall, this is the first extensive study of commercially available inside-out HFFO membrane modules.


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