Abatement Systems Research Articles

A comparison of in- and post-plasma catalysis for toluene abatement through continuous and sequential processes in dielectric barrier discharge reactors

In the non-thermal plasma catalysis system, VOCs degradation was significantly affected by the position of the catalyst, as well as operation mode. Hence, it is of great significance to evaluate the performance of In Plasma Catalysis (IPC) and Post Plasma Catalysis (PPC) systems for VOCs abatement using both continuous and sequential processes. Four packed-bed dielectric barrier discharge (DBD) systems were used to degrade toluene with different catalysts under diverse voltages in this study. Results showed that the IPC mineralization rates were higher as compared to PPC, regardless of whether the continuous or sequential processes was used, and irrespective of the applied voltage and type of packed catalyst (e.g. 77.00% and 96.06% in SPPC and SIPC at 20 kV with Ag/ZSM-5 packed). However, PPC was superior to IPC in O3 and N2O reduction. As the applied voltage was raised, the mineralization rate in different reactors increased significantly, yet CO2 selectivity was insusceptible to voltage variation. NTP alone exhibited a mineralization rate and CO2 selectivity of 9.67%–22.62% and 53.85%–58.26%, respectively. While the mineralization rate and CO2 selectivity were remarkably improved with the presence of Ag/ZSM-5 (19.08%–41.59% and 93.99%–95.91% in CIPC). With respect to different catalysts investigated in this study, at 20 kV, Ag/ZSM-5 exhibited the highest mineralization rate - 96.06% in SIPC, and CO2 selectivity - 98.43% in SPPC; while the lowest concentrations of O3 (198 ppm) and N2O (8.01 ppm) were obtained in the Mn/ZSM-5 packed bed reactor. Possible reaction mechanisms were also proposed by analyzing the organic intermediates that were produced during continuous and sequential treatments, and remained in the adsorbents of IPC and PPC reactors.

OVERVIEW OF ODOUR MEASUREMENT METHODS: THE ODOUR OBSERVATORY AS AN INFORMATIVE TOOL FOR CITIZEN SCIENCE BASED APPROACHES TO ODOUR MANAGEMENT

Odour pollution is a well-known problem related to a number of different industrial activities. It is also one of the main causes of citizens’ complaints to local authorities. Specific programs are needed to manage persistent odour pollution problems within communities in order to avoid possible socio-environmental conflicts. The H2020 project D-NOSES (Distributed Network for Odour Sensing, Empowerment and Sustainability) aims to help citizens co-create local solutions in collaboration with industries, regional & local authorities, and odour experts. The project will develop an innovative bottom-up approach to odour pollution governance by combining citizen science and stakeholder management methods using a quadruple helix model. The first aim of this article is to introduce the D-NOSES project and its methodology. Aside from that, the article presents an overview of the existing odour impact assessment methods currently available to quantify odour pollution. Finally, the different odour measurement methods are compared in terms of their applicability and limitations. This overview will be made available online as a first step towards the development of the International Odour Observatory, a platform to be created within the D-NOSES project to help promote odour pollution management and resolve regulation issues. The platform will become a global resource on odour issues and also include information about odour abatement systems, chemical substances in odour emissions, and odour regulations around the world.

Ceco Environmental expands in UK

Ceco Environmental Corp has completed the acquisition of Environmental Integrated Solutions Ltd (EIS), a UK-based manufacturer and supplier of VOC abatement, odour control and air pollution control systems.

Ceco Environmental makes UK acquisition

Ceco Environmental Corp has completed the acquisition of Environmental Integrated Solutions Ltd (EIS), a UK-based manufacturer and supplier of VOC abatement, odour control and air pollution control systems.

New biomorphic filters to face upcoming particulate emissions policies: A review of the FIL-BIO-DIESEL project

With a high number of diesel vehicles worldwide, particulate emission control is an urgent issue with a global impact, from the health of citizens to commercial future of this technology in some transport segments. Particulate filters are widely used in automotive engines to comply emissions regulations, but current technologies have room for improvement as they add additional backpressure in the exhaust system, and efficient on-board regeneration process is challenging.The Fil-Bio-Diesel Project is a R&D initiative to improve current particle filtration systems, based on the development of novel biomorphic substrates. By replicating the biologic tissue of a wood precursor, a biomorphic silicon carbide with hierarchic orthotropic microstructure can be produced. The porosity, the pore size, and pore orientation of this bioceramic material can be tailored through the selection of a suitable precursor, widening the initially narrow relationship between filtration efficiency and pressure drop that characterizes granular ceramic materials. In this paper the methodology and main results of the Fil-Bio-Diesel Project are presented. This work shows the peculiar advantages of biomorphic silicon carbide through several experimental studies. The results show the potential of this novel filter substrate to be used in future particulate abatement systems.

The Design of a Vapor-Condensing Plume Abatement System and Devices for Mechanical Draft Cooling Towers

Cooling towers are widely used in many fields, but the generation of visible plumes has a serious impact on the environment. Moreover, the evaporation losses also cause a great waste of water. In this paper, a vapor-condensing plume abatement system was designed for a mechanical-draft cooling tower based on the mechanism of vapor plume generation. An effective method to achieve water-saving and eliminate the water fog generated in the cooling tower was proposed, and its feasibility was verified by using thermodynamic analysis. Next, the vapor-condensing plume abatement device was designed and used for both the confined space cooling tower (CSCT) and the free space cooling tower (FSCT). The surface type heat exchanger was adopted to design the vapor-condensing plume abatement device. Then a basic calculation flow and method were proposed to obtain thermodynamic operating parameters. According to the comparison between the results of theoretical calculation and practical engineering application, it was found that the designed vapor-condensing plume abatement system obviously benefits the water-saving of a mechanical-draft cooling tower and considerable economic benefits can be obtained. The contents presented provide the theoretical basis and technical support for the upgrade of the cooling tower and the design of the new cooling tower.

Numerical Simulation of a Wall-Flow Particulate Filter Made of Biomorphic Silicon Carbide Able to Fit Different Fuel/Biofuel Inputs

To meet the increasingly strict emission limits imposed by regulations, internal combustion engines for transport applications require the urgent development of novel emission abatement systems. The introduction of biodiesel or other biofuels in the engine operation is considered to reduce greenhouse gas emissions. However, these alternative fuels can affect the performance of the post-combustion systems due to the variability they introduce in the exhaust particle distribution and their particular physical properties. Bioceramic materials made from vegetal waste are characterized by having an orthotropic hierarchical microstructure, which can be tailored in some way to optimize the filtration mechanisms as a function of the particle distribution of the combustion gases. Consequently, they can be good candidates to cope with the variability that new biofuel blends introduce in the engine operation. The objective of this work is to predict the filtration performance of a wall-flow particulate filter (DPF) made of biomorphic silicon carbide (bioSiC) with a systematic procedure that allows to eventually fit different fuel inputs. For this purpose; a well-validated DPF model available as commercial software has been chosen and adapted to the specific microstructural features of bioSiC. Fitting the specific filtration and permeability parameters of this biomaterial into the model; the filtration efficiency and pressure drop of the filter are predicted with sufficient accuracy during the loading test. The results obtained through this study show the potential of this novel DPF substrate; the material/microstructural design of which can be adapted through the selection of an optimum precursor.

Radiogenic backgrounds in the NEXT double beta decay experiment

Natural radioactivity represents one of the main backgrounds in the search for neutrinoless double beta decay. Within the NEXT physics program, the radioactivity- induced backgrounds are measured with the NEXT-White detector. Data from 37.9 days of low-background operations at the Laboratorio Subterráneo de Canfranc with xenon depleted in 136Xe are analyzed to derive a total background rate of (0.84±0.02) mHz above 1000 keV. The comparison of data samples with and without the use of the radon abatement system demonstrates that the contribution of airborne-Rn is negligible. A radiogenic background model is built upon the extensive radiopurity screening campaign conducted by the NEXT collaboration. A spectral fit to this model yields the specific contributions of 60Co, 40K, 214Bi and 208Tl to the total background rate, as well as their location in the detector volumes. The results are used to evaluate the impact of the radiogenic backgrounds in the double beta decay analyses, after the application of topological cuts that reduce the total rate to (0.25±0.01) mHz. Based on the best-fit background model, the NEXT-White median sensitivity to the two-neutrino double beta decay is found to be 3.5σ after 1 year of data taking. The background measurement in a Qββ±100 keV energy window validates the best-fit background model also for the neutrinoless double beta decay search with NEXT-100. Only one event is found, while the model expectation is (0.75±0.12) events.

Photo-microfluidic chip reactors for propene complete oxidation with TiO2 photocalyst using UV-LED light

In this study, we present a photo-microreactor illuminated with a low power LED light as a highly efficient system to achieve the total oxidation of propene using a TiO2 photocatalyst. This abatement system (photo-microreactor) consists in an immobilized benchmark photocatalyst (TiO2, P25) inside a commercial glass microchannel chip (UV transparent microfluidic chips, internal volume of 9.5 μl) using a packed-bed configuration without any previous treatment. The P25 inside the microreactor shows a nearly homogenous filling of the particles resulting in a low pressure drop throughout the system. In terms of propene abatement (Catalytic activity), the P25 inside the commercial microreactor reaches total propene conversion (100%) under flow conditions at low concentrations (100 ppmv) due to shorter diffusion distances, large surface-to-volume ratios, efficient heat transfer, and the improved light penetration inside the microchannel. Moreover, the prepared microreactor uses a low consumption power (LED), low residence time and presents a relatively low pressure drop making this device (P25 inside a commercial microreactor) very interesting for the abatement of volatile organic compounds at low concentration for example at indoor ambient due to its small size (45 × 15 mm).

Peroxydisulfate activation by positively polarized carbocatalyst for enhanced removal of aqueous organic pollutants

Multi-walled carbon nanotubes (MWCNTs)/peroxydisulfate (PDS) is a green oxidative system for abatement of aqueous organic pollutants, while the powder form and poor cycling performance of the catalyst limit its practical application. To solve these problems, fabricating a MWCNT cathode (negative polarization) to coupling carbocatalysis-driven PDS activation with electrosorption of organic pollutant was previously demonstrated to be a possible solution to these problems. To further improve the activation efficiency of PDS, positive polarization of MWCNT electrode (anode) was adapted to activate PDS for removing acyclovir and phenol in this work. Under a working voltage of 1.2 V, the MWCNT anode was more efficient than the MWCNT cathode and the non-polarized MWCNT electrode for PDS activation and removal of organic pollutants, owing to the enhanced attraction between S2O82− anions and anode. Although the positive/negative polarization of MWCNT electrode doesn't alter the nonradical mechanism involved in MWCNTs/PDS system, theoretical calculations suggest that different polarization affect the electron configuration and oxidative capacity of activated S2O82− bounded to MWCNTs differently, and that the adsorbed S2O82− with stretched S–O bond and much higher oxidative capacity than that in the case of non-polarized MWCNT electrode is responsible for the MWCNTs anode, while adsorbed S2O82− with stretched O–O bond and slightly higher oxidative capacity is responsible for the MWCNTs cathode. Finally, implications of operation parameters including electrode potential, energy cost, pH, etc. on the elimination efficiency by MWCNT anode/PDS system were investigated and the results suggest that the MWCNT anode/PDS is an efficient and economical metal-free electrochemical oxidative system for organic contaminants remediation.

Ebara completes new Components Development and Innovation Centre in Fujisawa

Ebara Corp has built a ¥1 billion Components Development and Innovation Centre in Fujisawa, Japan for dry vacuum pumps and gas abatement systems.

Life cycle assessment of atmospheric emission profiles of the Italian geothermal power plants

After nearly a decade of only small development in capacity in deep geothermal sector in Europe, in recent years a resurgence of interest in geothermal power and the use of innovative technologies to increase and better exploit geo-thermoelectric generation has stolen the limelight from the scientific community. Differently from other types of energy sources, the environmental impacts determined by geothermal exploitation are extremely dependent on the geographical location. Life Cycle Assessment offers a powerful methodological approach for the investigation of the environmental footprint of power generation systems.Focusing on an unprecedented system-modelling approach for the investigation of an environmental impacts analysis of geo-thermoelectric activity in the Tuscany Region, Italy, in this work we perform a comprehensive environmental impact assessment for the calculation of atmospheric emissions profiles connected with the operational phase of the power plants. A clustering of all the geothermal installations in operation nowadays is performed by considering geographical representativeness This allows the identification of regional geothermal subareas. Moreover, an extensive data processing analysis is implemented with the aim of reconciling the great variability found among data collected. Results demonstrate that the efforts undertaken by the operator of the geothermal power plants to limit the impact of emissions, through abatement systems like AMIS, are quite effective. Indeed, in areas where mercury and ammonia concentration in fluids constitute a problem to deal with, nowadays the emissive patterns result comparable to the other ones. Notwithstanding, mercury and ammonia emissions, mainly emitted through the cooling towers, still represent a critical problem for all the geothermal fields. On the basis of our findings we conclude that potential chemical interactions and environmental impacts related to the variety of the compounds emitted should be object of future research and a further effort to minimize them.

Dust explosion risk in metal workings

Several episodes of metal dust explosions have been reported to have affected industries throughout the world, some of which have caused huge losses (Li et al., 2016). These dusts are typically wastes or by-products derived from machinery within metal manufacturing plants, which are collected in abatement systems (suction units, bag filters). A recent work by Marmo et al. (2017) has demonstrated the deflagration hazards of these dusts and how they are influenced by the particle size (mainly d10), chemical composition and metal oxide content.The dust samples studied in this work were collected from the following mechanical workings of metals.All these unit operations involve the generation of by-products or scraps that may be classified as dust, with different size distributions and chemical compositions, which of course depend on the nature of the processed goods. Among these, it is known that the aluminum industry is affected by a significant hazard, due to the high reactivity of aluminum dust. However, ferrous dust is also reactive and widespread. Light alloys, such as Magnesium alloys, are becoming frequent, especially in the automotive and aerospace industries. Therefore, new hazards are now coming to light.This work presents a study of 43 metal dust samples, collected at various process plants, and discusses how the unit operation that generated the dust samples may influence their ignition sensitivity and explosion violence. The paper includes size distribution and chemical characterization data, and SEM observations of the samples, as well as the results of KST and Pmax measurements.Of all the studied dusts, 59% were found to be explosible, according to the standard test (ISO 80079-20-2), while 100% of the samples collected at some of the dust abatement systems were explosible. Process dusts, such those collected at metal recovery plants from exhaust catalysts or foundry wastes, were found to be less hazardous. The findings of the work could contribute toward identifying the most hazardous operations and suggesting adequate explosion moderation measures for the metal manufacturing industry.

In-service performance assessment of electrostatic precipitators serving a rubber vulcanization process

We examined two emission abatement systems of some vulcanization ovens, serving a unit producing small rubber-based parts for automotive application. Each emission control unit treats the gases exh...

Carbonaceous Aerosols Generated from Wood Charcoal Production Plants in the South Korea Context

Herein, a case study discussing the effect of carbonaceous aerosol pollution, which is emitted during the charcoal kiln manufacturing processes or carbonization processes, on the atmospheric environment is presented . In South Korea, in situ analysis of different charcoal production plants specialized in the production of charcoal sauna indicate that the emitted organic carbon (OC) and elemental carbon (EC) aerosols are significantly influenced by the nature of the biomass and technological processes, i.e., treatment or emissions abatement systems for the exhaust effluent gases. In detail, total carbon (TC), which is calculated as the sum of OC and EC emission factors, varied widely from a charcoal production site to another ranging from 21.8 to 35.8 gTC/kg-oak, where the mean value for the considered production sites was approximately 28 gTC/kg-oak (N = 7 and sum = 196.4). Results indicate that the emission factors from a modern charcoal production process in South Korea are quantitatively lower in comparison with the traditional kiln. This study aims to propose advanced wood processes for the production of charcoal from the viewpoint of environmental protection policy and green engineering.

강제경매에서 최저매각가격제도와 저감제도의 문제

강제경매를 통하여 채권자는 자신의 채권을 최대한 만족시킬 수 있어야 하고 채무자는 되도록 최대한 자신의 채무를 청산할 수 있도록 하여야 한다. 또한 여러 차례의 경매에 따른 집행채무자의 이자 등 비용부담이 증가되지 않도록 하여야 한다. 그리고 절차의 신속성과 효율성을 통하여 집행법원의 업무 효율성을 높여야 한다.BR 그러나 현행 부동산의 강제경매제도에서 최저매각가격제도와 저감제도는 위와 같은 강제경매제도의 취지에 역행하는 실례를 보이고 있다. 즉 최저매각가격제도는 그 구체적 기준의 불명확성과 감정평가액을 최저매각가격으로 결정하는 관행으로 인해 매각률을 저하시켜 이해관계자의 이익도 저해하고 절차의 신속성과 효율성도 달성하지 못하고 있다. 저감제도의 경우도 새 매각이 이루어지는 경우 명확한 기준이 없이 법원별로 20% 아니면 30%로 저감하고 있고, 제한은 있지만 계속해서 저감함으로써 경매참여자들의 적극성을 떨어트려 매각률도 낮추게 되고 결국 염가 매각이 되어 채권자 등 이해관계자의 이익을 해치고 매각의 지연으로 인한 집행법원의 업무 부담도 높이고 있다. 최저매각가격제도와 저감제도는 함께 맞물려 돌아가면서 그 부작용을 증대시키는 경향이 있다.BR 따라서 두 제도는 폐지하고 새로운 제도로 대체하여야 할 것이다. 새로운 제도로 고려할 수 있는 것은 독일식의 매각 하한선을 두는 방법과 일본식의 매각기준가격과 매수가능가액이라는 두가지 기준을 두는 방식을 생각할 수 있다. 두 방식 중에 어느 방식이 우월하다고 단정적으로 판단하기는 어렵다. 두 제도 모두 앞서 언급한 경매제도의 취지에 부합하려는 노력의 산물이다. 그런데 우리나라는 잉여주의 하에서 소멸주의를 원칙으로 하고 예외적으로 인수주의를 병용으로 하고 있다. 반면에 독일은 최저입찰가격제도하에서 인수주의를 기본으로 하고 있는 등 우리와 제도적으로 많은 차이를 보이고 있다. 따라서 독일식 제도 도입에는 일본식 제도 도입보다는 더 신중한 검토가 필요하다.BR 그래서 우리와 같은 문제를 안고 있었던 일본이 저감제도를 폐지하고 최저매각가격제도를 매각기준가격제도와 매수가능가격제도로 개혁한 이후 매각률과 매각가율 모두 큰 폭으로 상승한 점은 우리에게 시사하는 바가 크다고 볼 수 있다. 즉 새로운 제도로는 현행 강제집행제도의 틀을 크게 바꾸지 않는다면 일본의 개혁을 참고할만하다고 생각한다.

Sustainable performance-oriented production practices in the Indian iron and steel industry: An empirical investigation

Capital-intensive industries consume fossil fuels for mass production with little concern for nature's assimilative capacity, which results in an accumulation of greenhouse gases (GHGs). Pollution abatement systems based on market-induced correctives and multi-national agreements works as ex-post remedial measures and have limited effectiveness in the reduction of GHGs. In this paper, we formulate the sustainable-structure-conduct-performance (S-SCP) paradigm as an ex-ante remedial measure by mimicking the structure-conduct-performance (SCP) paradigm to reduce the GHGs. By using a dynamic panel data, the workability of the S-SCP paradigm was tested on CO2 emissions for selected major Indian iron and steel industries (IISI). Our findings show that the green relative index was positively significant in respect of green value added (GREVA). However, green R&D and barriers to entry and exit were negatively significant in respect of GREVA. Overall, the S-SCP paradigm's test in ISII suggests that the incorporation of social cost into the firm's structure and conduct will achieve sustainable performance-oriented production practices that reduce CO2 emissions. We propose general suggestions on industrial parks for green technology innovation, management responsibility mechanisms, environmental impact assessment notifications and an Indian sustainable development commission.

The impacts of the sulphur emission regulation on the sulphur emission abatement innovation system in the Baltic Sea region

According to the Porter hypothesis, regulations on environmental emissions under certain conditions can promote eco-innovation. This is why the technological innovation systems (TIS) theory sees regulatory pressure as a major system function critical in the take-off phase. In other words, the design and timing of any regulation may be decisive for the regulatory outcome. The research seeks to provide empirical evidence on how the Baltic Sea Sulphur Emission Control Area (SECA) has impacted the technological innovation system within the Baltic Sea Region maritime sectors. The results (1) show that regulatory compliance gave a knowledge development that has made it possible for clean-tech companies to engage in entrepreneurial activities that created new markets, (2) empirically support the TIS theory and the Porter hypothesis, and (3) provide qualitative evidence on how businesses see environmental regulation.Graphical abstractThe innovation system for ship sulphur emission abatement.

Low emission flash-binary and two-phase binary geothermal power plants with water absorption and reinjection of non-condensable gases

The power production from geothermal resources with a high content of non-condensable gases (NCG) is concerning an increasing number of regions and may affect the sustainability relating to geothermal projects. The selection of an emission abatement system based on water absorption and reinjection of NCG back to the reservoir could solve the environmental impact, yet it implies significant power output penalty and water demand, as demonstrated in a recent paper by the authors (Manente et al., 2019) focused on the retrofit of existing flash steam power stations. A reconsideration of the plant design could result in a better integration with the absorption and reinjection section and finally reduce the associated requirements. To address this point, two “greenfield” plant layouts are investigated in this paper for utilization of a high enthalpy liquid dominated reservoir, where the single flash steam generation unit is complemented or even totally replaced by air cooled binary cycle units. The first layout is an “integrated flash-binary” plant based on a backpressure steam turbine and a bottoming ORC system, whereas the second layout consists in a “two-phase binary” plant. The performance of the two novel layouts is compared against that of a brownfield layout, first proposed in Manente et al. (2019), based on an existing single flash plant retrofitted with the absorption and reinjection system, using a consistent set of assumptions. The results show that the net power output remains almost unaltered because in the novel layouts the lower parasitic loads for gas compression counterbalance the lower production dictated by the air-cooled system and the irreversibility in the heat transfer between geothermal fluid and organic fluid. Thus, due to the better integration between power block and emission abatement section the net power output penalty of the novel layouts is contained within 2%. On the other hand, the hydrogen sulfide and carbon dioxide abatement efficiencies markedly increase as the removal of the cooling tower eliminates the secondary gaseous emissions and makes the entire steam condensate available for NCG absorption. In the integrated flash-binary plant design the overall H2S and CO2 abatement efficiencies reach 99% and 90%, respectively, without any external water demand, provided that measures are taken for a controlled precipitation of silica and other minerals from the geothermal brine prior to using it for NCG absorption.

Medically-derived radionuclides levels in seven heterogeneous urban wastewater treatment plants: The role of operating conditions and catchment area

In nuclear medicine radionuclides are administered to patients both for diagnosis or treatment. Subsequently, the excreta from patients, enriched in radionuclides, enter the sewerage networks and reach wastewater treatment plants (TPs). Characterization of inflow wastewaters, sewage effluents and sewage sludges in the seven different urban WWTPs in the Barcelona Metropolitan Area (BMA) has been done and 131I, 99mTc, 111In, 67Ga and 123I concentrations were determined by gamma-spectroscopy. In order to explain the diversity of nuclear medicine short-lived radionuclide concentrations found in the BMA, mean sewage sludge ages and wastewater hydraulic retention times were determined, NM services located and patient management guidelines described. Results were found to vary greatly among the different TPs in inflow wastewaters, sewage effluents and sewage sludges. 131I and 99mTc activity concentrations showed the highest values in most of the inflow wastewaters, sewage effluents and sewage sludges. In the integrated analysis of the present findings, a large-sized TP (320,000 m3/d) from the BMA urban wastewater treatment system shows higher levels and detection frequencies of medically-derived radionuclides. The maximums detected in the sludges from this TP, are partly explained by the relatively low sewage sludge ages. Furthermore, inflow wastewater hydraulic retention times and sludge ages in the TPs are long enough for decay of the short-lived nuclear medicine radionuclides studied (t1/2 ≤ 8d) in such a way that TPs work as abatement systems and decrease the levels of radioactivity both in the effluent and in the final sludge. An integrated analysis of 7 TPs from the same system has been carried out to go further into the dynamics of medically-derived radionuclides in it.