Experimental Study on Inactivation of Heterosigma akashiwo by Pulsed Electric Field and Engine Waste Heat Treatment

2013 ◽  
Vol 864-867 ◽  
pp. 1822-1825
Author(s):  
Jun Feng Zhou ◽  
Le Ping Xu ◽  
Zhong Cheng Wang ◽  
Ting Fei Xie ◽  
Kai Liang Yang
Keyword(s):  
Ballast Water ◽  
Pulse Width ◽  
Structural Integrity ◽  
Waste Heat ◽  
Cost Effective ◽  
Heterosigma Akashiwo ◽  
Aquatic Species ◽  
Electrode Gap ◽  
Preheating Temperature ◽  
Inactivation Effect

Ballast water (BW) is essential in maintaining the balance and structural integrity of ships during voyage. However, invasive aquatic species discharged through ballast water is one of the most serious problems posed nowadays in the marine environment. Experimental inactivation effect on Heterosigma akashiwo by combined PEF and engine waste heat pretreatment was studied. Effect factors such as pulsed voltage, electrode gap, pulse width and preheating temperature were explored, and its mechanism of inactivate the Heterosigma akashiwo was analyzed. It was prospected to be effective to inactive the mircoalgae of ships ballast water by combined PEF and engine waste heat so as to obtain a cost-effective BW treatment with minimized environmental impacts.

Inactivation of Phytoplankton in Ship’s Ballast Water by Pulsed Electric Field and Thermal Treatment

2015 ◽  
Vol 1092-1093 ◽  
pp. 1060-1063
Author(s):  
Jun Feng Zhou ◽  
Ting Fei Xie ◽  
Le Ping Xu ◽  
Rui Zhao
Keyword(s):  
Thermal Treatment ◽  
Electric Field ◽  
Ballast Water ◽  
Pulse Width ◽  
Pulsed Electric Field ◽  
Aquatic Species ◽  
Electrode Gap ◽  
Preheating Temperature ◽  
Ship’S Ballast Water ◽  
Ship Ballast Water

Invasive aquatic species discharged through ship ballast water is one of the most serious problems posed nowadays in the marine environment. The effect of inactivation of phytoplankton by pulsed electric field and thermal treatment was studied. Effect factors such as pulsed voltage, electrode gap, pulse width and preheating temperature were explored, and its mechanism of inactivation was analyzed. The combined effect of mild thermal and PEF treatments was shown to give more effective damage of phytoplankton than application of PEF treatment alone. The untreated ballast water sample pretreated at moderate temperature (323 K) and moderate PEF (E ≈10kV/cm) showed a noticeable enhancing of inactivation.

Study on Inactivation of Microalgae in Ship Ballast Water by Pulsed Electric Field and Heat Treatment

2012 ◽  
Vol 610-613 ◽  
pp. 3163-3166
Author(s):  
Jun Feng Zhou ◽  
Le Ping Xu ◽  
Dao Lun Feng ◽  
An Bang Hu ◽  
Ting Fei Xie
Keyword(s):  
Electric Field ◽  
Ballast Water ◽  
Waste Heat ◽  
Heating Temperature ◽  
Inlet Temperature ◽  
Electrode Gap ◽  
Peak Voltage ◽  
Experimental Parameters ◽  
Treatment Stage ◽  
Ship Ballast Water

Invasive aquatic species discharged through ship ballast water is one of the most serious problems posed nowadays in the marine environment. Inactivation effect on microalgae by combined PEF and engine waste heat pretreatment was studied. Effect factors such as pulsed peak voltage, pulsed frequency, electrode gap and heating temperature were explored, and its mechanism of inactivate the microalgae was analyzed. The results show that at the same experimental parameters, the inlet temperature of PEF treatment stage keeps at 24°C, the inactivation percentage is difficult to achieve 90% unless the electric field strength rises to 22 kV/cm. Once the PEF treatment sample is preheated to 48°C, the inactivation percentage will be up to 99% as the electric field strenth is just 10 kV/cm.

scholarly journals Bayesian maintenance decision optimisation based on computing the information value from condition inspections

2021 ◽  
pp. 1748006X2097812
Author(s):  
Guang Zou ◽  
Kian Banisoleiman ◽  
Arturo González
Keyword(s):  
Decision Making ◽  
Structural Integrity ◽  
Fatigue Cracking ◽  
Cost Effective ◽  
Offshore Structures ◽  
Information Value ◽  
Bayesian Decision ◽  
Maintenance Strategies ◽  
Optimal Maintenance ◽  
Maintenance Decision

A challenge in marine and offshore engineering is structural integrity management (SIM) of assets such as ships, offshore structures, mooring systems, etc. Due to harsh marine environments, fatigue cracking and corrosion present persistent threats to structural integrity. SIM for such assets is complicated because of a very large number of rewelded plates and joints, for which condition inspections and maintenance are difficult and expensive tasks. Marine SIM needs to take into account uncertainty in material properties, loading characteristics, fatigue models, detection capacities of inspection methods, etc. Optimising inspection and maintenance strategies under uncertainty is therefore vital for effective SIM and cost reductions. This paper proposes a value of information (VoI) computation and Bayesian decision optimisation (BDO) approach to optimal maintenance planning of typical fatigue-prone structural systems under uncertainty. It is shown that the approach can yield optimal maintenance strategies reliably in various maintenance decision making problems or contexts, which are characterized by different cost ratios. It is also shown that there are decision making contexts where inspection information doesn’t add value, and condition based maintenance (CBM) is not cost-effective. The CBM strategy is optimal only in the decision making contexts where VoI > 0. The proposed approach overcomes the limitation of CBM strategy and highlights the importance of VoI computation (to confirm VoI > 0) before adopting inspections and CBM.

scholarly journals Polycrystalline SnSe with a thermoelectric figure of merit greater than the single crystal

2021 ◽  
Author(s):  
Chongjian Zhou ◽  
Yong Kyu Lee ◽  
Yuan Yu ◽  
Sejin Byun ◽  
Zhong-Zhen Luo ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Single Crystal ◽  
High Performance ◽  
Figure Of Merit ◽  
Waste Heat ◽  
Electric Energy ◽  
Cost Effective ◽  
Tin Selenide ◽  
Tin Oxides ◽  
Thermally Conductive

AbstractThermoelectric materials generate electric energy from waste heat, with conversion efficiency governed by the dimensionless figure of merit, ZT. Single-crystal tin selenide (SnSe) was discovered to exhibit a high ZT of roughly 2.2–2.6 at 913 K, but more practical and deployable polycrystal versions of the same compound suffer from much poorer overall ZT, thereby thwarting prospects for cost-effective lead-free thermoelectrics. The poor polycrystal bulk performance is attributed to traces of tin oxides covering the surface of SnSe powders, which increases thermal conductivity, reduces electrical conductivity and thereby reduces ZT. Here, we report that hole-doped SnSe polycrystalline samples with reagents carefully purified and tin oxides removed exhibit an ZT of roughly 3.1 at 783 K. Its lattice thermal conductivity is ultralow at roughly 0.07 W m–1 K–1 at 783 K, lower than the single crystals. The path to ultrahigh thermoelectric performance in polycrystalline samples is the proper removal of the deleterious thermally conductive oxides from the surface of SnSe grains. These results could open an era of high-performance practical thermoelectrics from this high-performance material.

scholarly journals EFFECTIVE USE OF ROTARY FURNACE SHELL HEAT

2014 ◽  
Vol 54 (6) ◽  
pp. 414-419
Author(s):  
Julius Lisuch ◽  
Dusan Dorcak ◽  
Jan Spisak
Keyword(s):  
Waste Heat ◽  
Cooling System ◽  
Raw Materials ◽  
Significant Proportion ◽  
Rotary Furnace ◽  
Cost Effective ◽  
Total Energy Expenditure ◽  
Heat Losses ◽  
Controlled Cooling ◽  
Effective Use

<pre><pre>Significant proportion of the total energy expenditure for the heat treatment of raw materials are heat losses through the shell of rotary furnace. Currently, the waste heat is not used in any way and escapes into the environment. Controlled cooling system for rotary furnace shell (<span>CCSRF</span>) is a new solution integrated into the technological process aimed at reducing the heat loss of the furnace shell. Based on simulations and experiments carried out was demonstrated a significant effect of controlled cooling shell to the rotary furnace work. The proposed solution is cost-effective and operationally undemanding.</pre></pre>

scholarly journals Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size

2013 ◽  
pp. 5-9
Author(s):  
Ilona Barta-Juhász
Keyword(s):  
Heat Recovery ◽  
Waste Heat ◽  
District Heating ◽  
Cost Effective ◽  
Plant Size ◽  
Net Income ◽  
Renewable Energy Resources ◽  
Heating And Cooling ◽  
Emission Reduction Strategies ◽  
Cleaning Technology

The biogas sector has never before aroused so much attention as it does today. Combined heat and power (CHP) reliable and cost-effective technologies that are already making an important contribution to meeting global heat and electricity demand. Due to enhanced energy supply efficiency and utilisation of waste heat renewable energy resources, CHP, particularly together with district heating and cooling (DHC), is an important part of national and regional Green House Gas (GHG) emission reduction strategies. During my work I am going to use the basic data of a certain biogas plant than I assemble one model from that. Against the CHP technology I am going to plan a biogas cleaning-equipment. During my research it revealed, that in the case of a 1 MW output power plant it is not worthy to deal with biogas cleaning between national conditions. Investigating the quantity of heat recovery in the CHP technology it is obvious, that the net income at 1 m3 biogas is at least 72 times more than the cleaning technology (heat recovery is 0%).

Offloading Operability of Small Scale AG FLNG With Side-by-Side Moored Small Scale LNG Carrier in Offshore West Africa

2017 ◽  
Author(s):  
Mun-sung Kim ◽  
Eric Morilhat ◽  
X. C. Nguyen ◽  
Bo-hee Kim ◽  
Jung-moon Jang ◽  
...  
Keyword(s):  
West Africa ◽  
Relative Motion ◽  
Structural Integrity ◽  
Effective Means ◽  
Production Capacity ◽  
Cost Effective ◽  
Body Motion ◽  
Small Scale ◽  
Associated Gas ◽  
High Level

This study describes one of the technical solutions for Small Scale FLNG (SSFLNG)[1] development specifically designed to monetize Associated Gas (AG) of producing oil fields located within convenient distance of an existing LNG Plant or Port with LNG storage facility. Limited production capacity combined with short range small scale LNG carriers (SSLNGC), provide a cost effective means for LNG production. Ship to ship off-loading operation by loading arm has been considered in AG SSFLNG. Produced LNG is to be off-loaded from the SSFLNG to side-by-side moored SSLNGC. Relative motion and dynamic load acting on loading arm system in side-by-side mooring arrangement is one of key factors to estimate the offloading operability of the AG SSFLNG. In this paper, a numerical two-body motion analysis for the side-by-side moored SSFLNG in frequency- and time-domain is carried out. Also, the basic engineering work is carried out for the marine loading arms (MLA). Since the MLA reacts approximately as a linear system, it is calculated by a full spectral RAO analysis for each of the worst load cases issued from the spectral ranking. All loads and stresses inside the MLA are verified in accordance with EN1474-1[2] for the situations identified in the previous step. A high level fatigue analysis focused on the cryogenic swivel joints is carried out. Based on the numerical calculation for relative motion in side-by-side moored FLNG, we have been performed structural assessment for MLA in several environment conditions. The structural integrity of both MLA and the LNGC manifold are validated during offloading for Offshore West Africa.

Ultrasound and Nonlinear Resonant Testing of Nuclear Reactor Internals Bolts

2011 ◽  
Author(s):  
S. W. Glass ◽  
B. Thigpen ◽  
J. Renshaw
Keyword(s):  
Phased Array ◽  
Nuclear Reactor ◽  
Structural Integrity ◽  
Cost Effective ◽  
Life Extension ◽  
Safe Operation ◽  
Plant Life ◽  
Nuclear Plants ◽  
Bolt Failure ◽  
Reactor Internals

As many nuclear plants approach the end of their initial 40 year license period, inspection or replacement of their reactor internals bolts must be considered. This is consistent with the Materials Reliability Program (MRP 227/228) guideline for plant life extension [1,2]. Assurance of the internals structural integrity is essential for continued safe operation of these plants. If there is no suspicion or indication of bolt failure, simple inspection is normally more cost-effective than replacement. Inspection vendors have inspected thousands of internals bolts with conventional and Phased Array UT but different head configurations and bolt capture mechanisms mandate specific qualifications for each bolt type. In some cases, complex bolt and head geometries coupled with counter-bore and locking bar interferences render classical UT inspections difficult or impossible. A range of solutions to inspect reactor internals including these difficult-to-inspect-by-conventional-UT baffle bolts has been developed by several vendors [3]. This presentation references developments to make bolt inspection a relatively quick and easy task through adaptations to the SUSI submarine inspection platform, the extensive UT qualification work suitable for conventional UT plus more recent advanced nonlinear resonant techniques to distinguish between flawed or loose, vs. acceptable bolts where conventional UT cannot be applied. Initial evaluations show that these advanced techniques may have the ability to reliably detect smaller flaws than previously possible with conventional techniques as well as provide information on bolt tightness.

scholarly journals Health and Structural Integrity of Monitoring Systems: The Case Study of Pressurized Pipelines

2020 ◽  
Vol 10 (17) ◽  
pp. 6023
Author(s):  
Vladimír Chmelko ◽  
Martin Garan ◽  
Miroslav Šulko ◽  
Marek Gašparík
Keyword(s):  
Real Time ◽  
Structural Integrity ◽  
Human Life ◽  
Cost Effective ◽  
Monitoring Systems ◽  
Long Run ◽  
Operational Safety ◽  
Pipeline Systems ◽  
Safety Parameters ◽  
High Pressure Pipeline

In the operation of some structures, particularly in energy or chemical industry where pressurized pipeline systems are employed, certain unexpected critical situations may occur, which must be definitely avoided. Otherwise, such situations would result in undesirable damage to the environment or even the endangerment of human life. For example, the occurrence of such nonstandard states can significantly affect the safety of high-pressure pipeline systems. The following paper discusses basic physical prerequisites for assembling the systems that can sense loading states and monitor the operational safety conditions of pressure piping systems in the long-run. The appropriate monitoring system hardware with cost-effective data management was designed in order to enable the real-time monitoring of operational safety parameters. Furthermore, the paper presents the results obtained from the measurements of existing real-time safety monitoring systems for selected pipeline systems.

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