ULTRASOUND‐ASSISTED TREATMENT OF KAOLIN ARTIFICIALLY CONTAMINATED WITH PHENANHTRENE, FLUORANTHENE AND HEXACHLOROBENZENE

2010 ◽  
Vol 18 (4) ◽  
pp. 251-258 ◽  
Author(s):  
Pham Thuy Duong ◽  
Reena Amatya Shrestha ◽  
Mika Sillanpää ◽  
Jūratė Virkutytė

Application of ultrasound in decontamination of polluted soil is a new and promising technology. The feasibility of ultrasonic treatment of clayey soil (kaolin) highly contaminated with persistent organic pollutants (POPs), such as phenanthrene (PHE), fluoranthene (FLU), hexachlorobenzene (HCB), was the main target of the work. The laboratory experiments were conducted at various conditions (moisture, power, irradiation duration and the initial concentration of contaminants) and the effects of these parameters on the process efficiency were examined. Experimental results showed that ultrasonication alone has a potential to remove POPs, although the removal efficiencies were relatively low when a short irradiation duration (1–6 hours) was adopted. Intermittent ultrasonication over longer periods (up to the total of 46 hours) increased the removal efficiencies to 45% of HCB and nearly 100% of PHE. The optimum moisture content of the slurry was found to be in the range of 50–70%. The total electric energy consumption during the experiments using the optimum operational conditions (100 W and above ultrasound irradiation power and 67% moisture content) was 1.5 kWh in comparison to 1.84 kWh during experiments utilizing minimum operational conditions. Santrauka Ultragarsines radiacijos taikymas dirvai valyti yra nauja, tačiau sparčiai pletojama technologija. Pagrindinis šio darbo tikslas buvo ivertinti ultragarso poveiki atspariu organiniu teršalu, tokiu kaip: heksachlorobenzenas (HCB), fenantrenas (PHE) ir fluorantenas (FLU), – degradavimui dirbtinai užterštame kaoline. Laboratoriniai eksperimentai atlikti pasirenkant ivairu dirvos dregnuma, ultragarso intensyvuma, stipruma, radiacijos trukme ir pradines organiniu teršalu koncentracijas bei ivertinant ju poveiki kaolino valymo efektyvumui. Rezultatai irode, kad ultragarsas gali būti taikomas dirvai valyti, tačiau efektyvumas nebuvo itin didelis kaolina švitinant nuo 1 iki 6 valandu. Taikant kintama radiacija (iki 46 valandu), HCB šalinimas pagerejo iki 45 %, o PHE – net iki 100 %. Valant organinius teršalus optimali kaolino dregme buvo 50–70 %. Taikant optimalias reakcijos salygas (100 W ir daugiau, 67 % dregmes), elektros energijos sunaudota mažiau (1.5 kWh) nei kai reakcijos salygos minimalios (1,84 kWh). Резюме Применение ультразвуковой радиации для очистки почв является новой, быстро развивающейся технологией. Основной целью работы было оценить воздействие ультразвука на деградацию устойчивых органических загрязняющих веществ, таких, как гексахлоробензен, фенантрен и флуорантен, в искусственно загрязненном каолине. Лабораторные исследования проводились при разной влажности почвы, интенсивности ультразвука, его мощности, длительности радиации и начальных концентрациях органических соединений, а также при учете их воздействия на эффективность очистки каолина. Результаты показали, что ультразвук может применяться для очистки почв, однако эффективность не была высокой при воздействии излучением в течение от одного до шести часов. При применении меняющейся радиации (до 46 часов) эффективность очистки от гексахлоробензена увеличилась до 45%, а от фенантрена даже до 100%. Оптимальной для очистки от органических соединений оказалась 50– 70%-ая влажность каолина. Потребление электроэнергии при оптимальных условиях реакции (100 W и больше, 67%-ая влажность) было меньшим, чем при минимальных условиях реакции (1.84 kWh).

1999 ◽  
Vol 40 (4-5) ◽  
pp. 187-194 ◽  
Author(s):  
C. Collivignarelli ◽  
G. Bertanza

This paper deals with the development of technologies aimed to upgrade existing waste water treatment plants, paying attention to high process efficiencies and low costs. We established conditions for good N removal efficiencies in extended aeration activated sludge plants which are not equipped with specific denitrification steps. The experimental process is based on establishing conditions in the biological reactor which allow simultaneous nitrification and denitrification without alternating (in time or in space) anoxic and aerobic phases; the aeration system is controlled by means of dissolved oxygen and/or redox potential measurements. The research was carried out on two real plants (design size: 2,500 p.e. and 440,000 p.e. respectively). The main advantages of this process (even if some aspects are still under investigation) are: total N removal efficiencies similar to a pre-denitrification process, without the need for an anoxic basin and decrease of operating costs (savings in electric energy consumption in particular) due to the low oxygen concentration required in the biological reactor.


2007 ◽  
Vol 77 (9) ◽  
pp. 635-644 ◽  
Author(s):  
Prashantkumar Gulabrao Patil ◽  
Pramod Madhukar Padole ◽  
Jugalkishar Fulchand Agrawal ◽  
Arun Bhimrao Dahake

1997 ◽  
Vol 35 (6) ◽  
pp. 53-61 ◽  
Author(s):  
G. Bertanza

This work deals with the study of technologies aimed to upgrade the existing waste water treatment plants, paying attention to high process efficiencies and low costs. We verified the possibility to reach high N removal efficiencies in extended aeration activated sludge plants which are not equipped with specific denitrification steps. The experimented process is based on particular conditions, kept in the biological reactor, which allow simultaneous nitrification and denitrification, even without alternating (in time or in space) of anoxic and aerobic phases: aeration system is controlled by means of dissolved oxygen and redox potential measurements. Our research was carried out, for about three years, on a laboratory plant (V = 40 L) fed with synthetic waste water, a pilot scale plant (V = 1,400 L) fed with waste water coming from a real plant, and two full-scale plants (1,500-2,000 p.e.). The main advantages of the studied process are the following: high total N removal efficiencies (up to 90%) without the realization of new specific basins for the denitrification process; decreasing of operating costs (savings in Electric Energy consumption) due to the low oxygen concentration required in the biological reactor.


2012 ◽  
Vol 7 (3) ◽  
pp. 23-32 ◽  
Author(s):  
Miloslav Bagoňa ◽  
Dušan Katunský ◽  
Martin Lopušniak ◽  
Marián Vertaľ

1991 ◽  
Vol 23 (10-12) ◽  
pp. 2011-2018 ◽  
Author(s):  
T. Murakami ◽  
K. Sasabe ◽  
K. Sasaki ◽  
T. Kawashima

The possible volume reduction and stabilization of the sewage sludge associated with the melting process are expected to be greater than with the incineration process. In addition, melted slag can be utilized. However, since the melting process requires a very high temperature to melt inorganics (ash) in the sludge, the technologies to minimize energy consumption, to establish system operation and to prolong durability of facilities should be developed. This paper discusses the auxiliary fuel consumption as follows.(1)Preparation of a model that provides the auxiliary fuel consumption of the melting system on the basis of the mass and heat balances.(2)Evaluation of the auxiliary fuel consumption in the above model using the cake moisture content, the volatile solids of the cake, the dried cake moisture content and the melting temperature as parameters.(3)Examination of the operational conditions for an energy saving melting system based on the results of (1) and (2) above.


2021 ◽  
Vol 13 (8) ◽  
pp. 4180
Author(s):  
Andrzej Czerepicki ◽  
Tomasz Krukowicz ◽  
Anna Górka ◽  
Jarosław Szustek

The article presents an analysis of priority solutions for trams at a selected sequence of intersections in Warsaw (Poland). An analysis of the literature has shown the topicality of this issue. A computer simulation model of a coordinated sequence of intersections was constructed. Three test scenarios were designed: the existing control system, the new coordinated fixed-time control system, and the adaptive control system with active priority. In the simulation process, detailed travel characteristics of trams and other traffic participants in a selected section were obtained for the three varying scenarios. Electric energy consumption for traction needs and pollutant emissions was then estimated for each of the variants. It was concluded that for the analyzed configuration, implementation of the adaptive priority will result in a reduction of tram time losses by up to 25%, a reduction in energy consumption by up to 23%, and a reduction in the emission of pollutants from individual vehicles by up to 3% in relation to the original variant. The conducted research may be the basis for a comprehensive method of assessing the effectiveness of applying the adaptative priority when designing new tramway lines and modernizing the existing ones.


1999 ◽  
Vol 5 (3) ◽  
pp. 307-310
Author(s):  
B. Nyman

Abstract By means of laboratory experiments it is shown that the penetration depth of a treatment of concrete with Silane depends strongly on the duration of suction and on the moisture content of the concrete. The necessary duration of suction can be estimated for any required penetration depth.


2012 ◽  
Vol 16 (3) ◽  
pp. 131
Author(s):  
Didik Ariwibowo

Didik Ariwibowo, in this paper explain that energy audit activities conducted through several phases, namely: the initial audit, detailed audit, analysis of energy savings opportunities, and the proposed energy savings. Total energy consumed consists of electrical energy, fuel, and materials in this case is water. Electrical energy consumption data obtained from payment of electricity accounts for a year while consumption of fuel and water obtained from the payment of material procurement. From the calculation data, IKE hotels accounted for 420.867 kWh/m2.tahun, while the IKE standards for the hotel is 300 kWh/m2.tahun. Thus, IKE hotel included categorized wasteful in energy usage. The largest energy consumption on electric energy consumption. Largest electric energy consumption is on the air conditioning (AC-air conditioning) that is equal to 71.3%, and lighting and electrical equipment at 27.28%, and hot water supply system by 4.44%. Electrical energy consumption in AC looks very big. Ministry of Energy and Mineral Resources of the statutes, the profile of energy use by air conditioning at the hotel by 48.5%. With these considerations in the AC target for audit detail as the next phase of activity. The results of a detailed audit analysis to find an air conditioning system energy savings opportunities in pumping systems. Recommendations on these savings is the integration of automation on the pumping system and fan coil units (FCU). The principle of energy conservation in the pumping system is by installing variable speed drives (VSD) pump drive motor to adjust speed according to load on the FCU. Load variations FCU provide input on the VSD pumps to match. Adaptation is predicted pump can save electricity consumption up to 65.7%. Keywords: energy audit, IKE, AC


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