Cleanup Facility Research Articles

Raspberry leaf blotch emaravirus in Bosnia and Herzegovina: population structure and systemic movement.

Raspberry leaf blotch virus (RLBV) is the putative agent of the homonymous disease and even though Bosnia and Herzegovina is a major producer worldwide there is no report of the virus presence in the country. We studied the virus population structure and assessed its ability to move systemically. RLBV is widespread in production areas and has a homogeneous population structure; leading to the hypothesis that the primary mode of dissemination is propagation material. The ability of the virus to move systemically eliminates propagation of root cuttings as a viable option to obtain RLBV-free plants, leaving RT-PCR screening as the better option to propagate RLBV- free plants in the absence of clean-up facilities or certification programs in the country.

Environmental contamination with persistent cyclic mustard gas impurities and transformation products

ABSTRACTThe battlefield of Verdun has seen some of the heaviest shelling in the history of mankind. This site as well as clean-up facilities in Germany may constitute contamination hot-spots and point-sources with leaking to groundwater. This study collected existing toxicological and ecotoxicological data on mustard gas degradation products, together with physical – chemical properties of listed compounds. It also provides quantities of these products measured in the groundwater of France, Germany and the pore water of the Baltic Sea. We indicate a deficiency of information on the toxicity of 1-oxa-4,5-dithiepane and 1,2,5 – trithiepane. In the groundwater of the German city of Munster 1-oxa-4,5-dithiepane was measured up to 250 µg/L, thus exceeding safe levels. Ecotoxicological studies classify this compound as toxic to aquatic organisms. 1,2,5-trithiepane is not a persistent compound. It was measured, however, in the groundwater at 1 µg/L level. This suggests that it could be formed from an active source of mustard gas. Considering the lack of toxicological data and the uncertainty about the amount of munition deposits, we suggest that research into the toxicity and exposure of, 1-oxa-4,5-dithiepane and 1,2,5 – trithiepane is needed for sites of concern.

Определение условий устойчивости положения надземного трубопровода на опорах при пропуске СОД

Определение условий устойчивости положения надземного трубопровода на опорах при пропуске СОД

High quality draft genome sequence of Olivibacter sitiensis type strain (AW-6(T)), a diphenol degrader with genes involved in the catechol pathway.

Olivibacter sitiensis Ntougias et al. 2007 is a member of the family Sphingobacteriaceae, phylum Bacteroidetes. Members of the genus Olivibacter are phylogenetically diverse and of significant interest. They occur in diverse habitats, such as rhizosphere and contaminated soils, viscous wastes, composts, biofilter clean-up facilities on contaminated sites and cave environments, and they are involved in the degradation of complex and toxic compounds. Here we describe the features of O. sitiensis AW-6T, together with the permanent-draft genome sequence and annotation. The organism was sequenced under the Genomic Encyclopedia for Bacteria and Archaea (GEBA) project at the DOE Joint Genome Institute and is the first genome sequence of a species within the genus Olivibacter. The genome is 5,053,571 bp long and is comprised of 110 scaffolds with an average GC content of 44.61%. Of the 4,565 genes predicted, 4,501 were protein-coding genes and 64 were RNA genes. Most protein-coding genes (68.52%) were assigned to a putative function. The identification of 2-keto-4-pentenoate hydratase/2-oxohepta-3-ene-1,7-dioic acid hydratase-coding genes indicates involvement of this organism in the catechol catabolic pathway. In addition, genes encoding for β-1,4-xylanases and β-1,4-xylosidases reveal the xylanolytic action of O. sitiensis.

Evaluation of the Effectiveness of a New Technology for Extraction of Insoluble Impurities from Nuclear Power Plant Steam Generators with Purge Water

An experimental technology for the removal of insoluble impurities from a horizontal steam generator with purge water during planned shutdowns of the power generating unit is improved through a more representative determination of the concentration of impurities in the purge water ahead of the water cleanup facility and a more precise effective time for the duration of the purge process. Tests with the improved technique at power generating unit No. 1 of the Rostov Nuclear Power Plant show that the efficiency with which insoluble impurities are removed from the steam generator volume was more than two orders of magnitude greater than under the standard regulations.

Olivibacter oleidegradans sp. nov., a hydrocarbon-degrading bacterium isolated from a biofilter clean-up facility on a hydrocarbon-contaminated site

A novel hydrocarbon-degrading, Gram-negative, obligately aerobic, non-motile, non-sporulating, rod-shaped bacterium, designated strain TBF2/20.2(T), was isolated from a biofilter clean-up facility set up on a hydrocarbon-contaminated site in Hungary. It was characterized by using a polyphasic approach to determine its taxonomic position. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate is affiliated with the genus Olivibacter in the family Sphingobacteriaceae. It was found to be related most closely to Olivibacter ginsengisoli Gsoil 060(T) (93.3% 16S rRNA gene sequence similarity). Strain TBF2/20.2(T) grew at pH 6-9 (optimally at pH 6.5-7.0) and at 15-42 °C (optimally at 30-37 °C). The major fatty acids were iso-C(15:0) (39.4%), summed feature 3 (iso-C(15:0) 2-OH and/or C(16:1)ω7c; 26.0%), iso-C(17:0) 3-OH (14.5%) and C(16:0) (4.5%). The major menaquinone was MK-7 and the predominant polar lipid was phosphatidylethanolamine. The DNA G+C content of strain TBF2/20.2(T) was 41.2 mol%. Physiological and chemotaxonomic data further confirmed the distinctiveness of strain TBF2/20.2(T) from recognized members of the genus Olivibacter. Thus, strain TBF2/20.2(T) is considered to represent a novel species of the genus Olivibacter, for which the name Olivibacter oleidegradans sp. nov. is proposed. The type strain is TBF2/20.2(T) (=NCAIM B 02393(T) =CCM 7765(T)).

High-fidelity system modeling of advanced nuclear energy systems approaching a zero-nuclear-waste limit

This paper will present a high-fidelity system analysis of advanced nuclear energy systems approaching a zero-nuclear-waste limit. The focus will be on achievable performance characteristics. The applied high-fidelity system modeling approach will be discussed with illustrations using obtained physics simulation results. The near-term deployable dedicated small 14 MeV-neutron waste incineration back-end clean-up facilities are envisioned as advanced incinerators that are used in combination with thermal reactors (Westinghouse AP1000 and Generation IV VHTR are considered in the present study) to minimize the remaining long-lived radioactive species. These 14 MeV transmuters are viewed as small facilities designed to reduce waste inventories prior to reprocessing stages minimizing spent fuel activity levels and repository requirements. It is envisioned that under sustainable nuclear energy scenario small clean-up facilities will eventually evolve into self-consistent complexes producing electricity and serving as energy sources for industrial applications. The paper discusses physics features of these advanced systems and challenges of their conclusive evaluations.

Cost Allocation Strategies at Florida Petroleum Cleanup Facilities: A Tiered Decision Approach

Cost allocations are conducted at Florida petroleum facilities between the state and private parties for the combined cleanup of multiple discharges that are not all eligible for state funding. This article proposes a tiered decision process for determining allocation strategies for cleanup costs and a method of apportioning costs by mass and volume to account for various plume scenarios and the significant constituents of petroleum contamination in soil and groundwater. The approach incorporates elements of the methods used at Superfund sites and addresses specific requirements of the Florida petroleum cleanup-funding program. More than 100 cost allocations were concluded using the approach.

超臨界水中におけるチオ硫酸ナトリウムおよびチオシアン酸ナトリウムの分解反応

For the purpose of establishing recycle technology to reduce environmental load, technical and practical development of supercritical water is required. An area of high impact on above purpose is in the recycling of sulfur-containing wastes that are produced in gas clean-up facilities of coal gasification processes. For this purpose, pseudo-first order rate constants were evaluated for thiosulfate ion and thiocyanic ion decomposi-tion in subcritical water and in supercritical water (SCW). Experiments were conducted to decompose so-dium thiosulfate and sodium thiocyanate at 340-400°C and at 25MPa. Thiosulfate ion could be decomposed 100% in 10s reaction time to sulfite, sulfate, and sulfide ions in SCW. Thiocyanic ion could be decomposed 20% in 30s in SCW. When thiosulfate ion was added to sodium thiocyanate solution, however, decomposition rate increased to about 30%. Main reaction pathways and kinetics were determined with a flow reactor. The results show that thiosulfate ion can be completely decomposed in SCW, but that decomposition of thiocyanic ion in SCW requires different conditions, additives, or oxidants.

Analysis of Steady-State Filtration and Backpulse Process in a Hot-Gas Filter Vessel

The need to develop a technology for clean and efficient electric power generation has led to the development of advanced pressurized fluidized bed combustors (PFBC) and integrated gasification combined cycles (IGCC). The effective filtration of hot gases for removal of ash and sulfur sorbent, however, is the key to the success of these advanced coal energy systems. Recently, attention has been given to the use of ceramic candle filters for hot-gas cleaning. The ash cake formation on these filters needs to be removed by the backpusle for their successful operation. In this paper, steady-state filtration as well as the transient gas flow during the backpulse process in the integrated gasification and cleanup facility (IGCF) (located at the National Energy Technology Laboratory, NETL) is studied. The steady-state filtration condition is first evaluated, using a compressible heat-conducting flow analysis. Particle transport patterns are studied, and the deposition patterns of 1-30 w m particles on the cerami...

Design of a catalytic exhaust clean-up unit for ITER

A fuel clean-up process for torus exhaust gases specified for ITER based on permeation of hydrogen isotopes through palladium/silver, catalytic cracking or conversion reactions, and isotopic swamping has been developed. The different steps of the process, which was designated C aper, have already been demonstrated with relevant concentration of tritium at the laboratory scale and for the most part, also at a technical scale. The experimental results have been used to form the basis of the detailed engineering and design of a torus exhaust clean-up plant for ITER. This paper describes all the essential parts of the clean-up facility along with principal experimental results, outlines key safety features and summarizes the P&I diagram.

Study of Ammonia Removal from Coal-Gasified Fuel

In integrated coal gasification combined-cycle power-generation (IGCC) systems, ammonia in gasified fuel is passed through a hot/dry type gas clean-up facility into a gas turbine. The ammonia is converted to nitrogen oxides in the gas turbine combustion process. Therefore, ammonia removal from coal-gasified fuel effectively reduces NO x emissions in IGCC systems. We clarified the optimum NO/NH 3 ratio, the optimum concentration of added O 2, and the influence of CO, H 2, and CH 4 in the coal-gasified fuel on NH 3 decomposition and NO reduction through experiments using a tubular flow reactor and numerical analysis based on reaction kinetics. The main results were as follows: (1) The optimum NO/NH 3 ratio for maximizing NH 3 decomposition and NO reduction was about 1. (2) The NH 3 decomposition ratio depended only on H 2, and decreased rapidly with increasing H 2 concentration. (3) The NO reduction ratio decreased with an increasing H 2 concentration. (4) The remaining CH 4, which was not decomposed by pyrolysis, increased with an increasing CH 4 concentration and caused the reaction temperature to rise, as opposed to cases of CO and H 2. (5) The method was effective in decreasing total fixed nitrogen (TFN) by up to 40% and minimizing the total concentration of remaining NH 3 and NO in air-blown, coal-gasified fuel.

Analysis of operational filtration data Part II: Incomplete cleaning of candle filters

Abstract A model has been developed for hot-gas filtration by candle filters, which includes incomplete removal of the filter cakes by the cleaning backpulses of compressed air. Operational data from the filtration system of the Integrated Gasification and Cleanup Facility at the Federal Energy Technology Center were analyzed with the model and used to estimate the cake permeability, thickness of cake left on the filter after each backpulse, and total cake thickness vs. time. The statistical R 2 for the fit of the incomplete-cleaning model was 0.93, compared to the R 2 = 0.78 previously obtained for a fit of the ‘ideal filtration’ model to the same data set.

Particle Transport and Deposition in a Hot-Gas Cleanup Pilot Plant

ABSTRACT Development of hot-gas filtration systems for advanced clean coal technologies has attracted considerable attention in recent years. The Integrated Gasification and Cleanup Facility (IGCF), which is an experimental pilot plant for testing performance of ceramic candle filters for hot-gas cleaning, has been operational at the Federal Energy Technology Center (FETC) in Morgantown, West Virginia, for several years. The present work describes a computer simulation study of gas flow and particle transport and deposition in the IGCF filter vessel with four filters. The stress transport model of FLUENT™ code is used for evaluating the gas mean velocity and the root mean-square fluctuation velocity fields in the IGCF filter vessel. The instantaneous fluctuation velocity vector field is simulated by a filtered Gaussian white-noise model. Ensembles of particle trajectories are evaluated using the recently developed PARTICLE code. The model equations of the code include the effects of lift and Brownian moti...

Analysis of Operational Filtration Data Part III: Re-entrainment and Incomplete Cleaning of Dust Cake

ABSTRACT Operational data for the hot-gas filtration system of the Integrated Gasification and Cleanup Facility (IGCF) at the Federal Energy Technology Center are carefully analyzed. A model that includes re-entrainment of filter-cake fragments following cleaning of the candle filters, as well as incomplete removal of cake from the filters by the cleaning backpulses of compressed air, is developed and used to interpret the data. The parameters of the model are evaluated with a least-square error fit procedure. It is shown that inclusion of the re-entrainment model significantly improves the fit to the data during the short interval (∼50 s after each backpulse) during which re-entrainment is predicted to occur by particle-transport modeling. The re-entrainment/incomplete-cleaning model is used to evaluate the buildup of filter-cake thickness and the filter-cake permeability. Both effects were significant for the data analyzed.

Analysis of operational filtration data part I. Ideal candle filter behavior

Operating data for the hot-gas filtration system of the Integrated Gasification and Cleanup Facility (IGCF) at the Federal Energy Technology Center are carefully analyzed. A model for candle filters is developed and used to describe the ideal filtration process. The parameters of the model are evaluated with a least-square error fit procedure. It is shown that the model predicts the time variation of the pressure drop with reasonable accuracy. The model is used to evaluate the buildup of filter-cake thickness and the filter-cake permeability.

97/02275 Shell/METC high temperature high pressure filtration program

The purpose of this paper is to present the program objectives and non-proprietary results of the high temperature, high pressure filtration work done under the Shell/METC Cooperative Research and Development Agreement (CRADA) 93-011. The primary purpose of this CRADA was to collect data relevant to the design and operation of dry particulate solids filters employing rigid ceramic (silicon carbide) filter elements in a gasifying environment at conditions of commercial interest; e.g., temperatures up to 1100 {degrees}F and system pressures between 300 and 350 psia. Shell provided the ceramic filter elements and evaluated the exposed filter elements. METC installed the filter elements and operated their 10 inch Fluid Bed Gasification and Cleanup facility as required for their Hot Gas Clean-up Test Program. Filter elements were removed from service after approximately 254, 525 and 868 hours of on-line operation. The exposed filter elements were analyzed and compared to an unexposed element with respect to changes in physical property.

97/01055 Development of 3 t/d coal gasification system in Korea

In order to understand gasification characteristics as well as to predict the key technical problems anticipated in commercial-size coal gasification systems, a bench scale coal gasifier has been constructed and is being tested. Through the operation of 3 ton-coal/day (T/D) bench scale unit coal gasifier from 1995, basic operation characteristics of pressurized coal gasifier for power generation will be established for imported bituminous and subbituminous coals to Korea. The 3 T/D gasifier is anticipated to provide pressurized coal gas to the future hot gas cleanup facility and to the test facility of producing methanol/dimethyl-ether. In addition, software-approach to the Integrated Gasification Combined Cycle has been also briefly described.

Effect of Oxygen Amendments and Soil pH on Bioremediation of Industrially Contaminated Soils

Polynuclear aromatic hydrocarbons (PAHs), by-products of coal conversion processes, have contaminated soils near coal plant sites either through accidental spills or systematic discharge. Because these compounds are carcinogenic, mutagenic, and teratogenic, remediation of such sites is a legitimate concern. For this study, contaminated soil samples were obtained from the Alberta Research Council (ARC) primary clean-up facility. Preliminary analysis of the soil was done for contaminant characterization and determination of initial contamination levels. Acinetobacter sp. was used for aerobic treatment of soil over a five-week period under optimum conditions. Because the rate of biodegradation is influenced by the pH, it is of interest to study the effect of pH on remediation efficiency in the physiological pH range of 5.0 to 9.0. Also, oxygen amendment via hydrogen peroxide solution was used to improve remediation in a packed bed, and the results were compared with those obtained under completely mixed conditions.

石炭ガス化複合発電用乾式ガスクリーンアップ技術開発 乾式ガスクリーンアップ３方式の開発状況

IGCC systeme are expected to be of practicable use in the near future, in view of its prominent environmental compatibility and higher thermal energy efficiency. The highest themal efficiency is achievable when the gas cleanup is conducted at a high temperature and pressure. To make the most of these characteristics of high thermal efficiency that is associated with this IGCC, development of hot gas cleanup technology is essential.IGC Association installed a 200t/d pilot plant in 1990 at Nakoso site, and a hot gas cleanup facility that is composed of the fluidized-bed desulfurization unit and the granular bed dust collector has been operating. Also, Fixed-bed type and Moving-bed type hot gas cleanup facilities were installed in 1993. The characteristics of desulfurization and dust removal were investigated using these facilities. Sulfur and dust concentration in the clean gas were under the target value. From its result, we confirmed that all the 3 types hot gas cleanup processes have high performance.