Sample records for experimental coal columns

  1. Plant practices in fine coal column flotation

    Davis, V.L. Jr.; Bethell, P.J.; Stanley, F.L. [Pittston Coal Management Co., Lebanon, VA (United States); Luttrell, G.H. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States). Dept. of Mining and Minerals Engineering


    Five 3 m (10 ft) diameter Microcel{trademark} flotation columns were installed at Clinchfield Coal Company`s Middle Fork preparation facility in order to reduce product ash and increase recovery and plant capacity. The Middle Fork facility is utilized for the recovery of fine coal from a feed stream that consists primarily of 1.5 mm x 0 material. The columns replaced conventional flotation cells for the treatment of the minus 150 {micro}m fraction while spirals are used to upgrade the plus 150 {micro}m material in the plant feed. The addition of the column flotation circuit resulted in an increase in plant capacity in excess of 20 percent while reducing the flotation product ash content by approximately 7 percentage points. Flotation circuit combustible recovery wa increased by 17 percentage points. This paper discusses circuit design, commissioning, and sparging system design. Circuit instrumentation, level control, reagent system control, performance comparisons with conventional flotation, and general operating procedures are also discussed.

  2. Column flotation in coal: does it make `cents?`

    Laurila, M.J.


    Column flotation technology was introduced into the coal industry in 1986. The column can produce higher grade concentrates than conventional cells. This has created a niche market for columns in recovering ultrafine (-100 mesh) coal from waste streams. However, column flotation is much more expensive than froth flotation and columns can only process a maximum of 20 tons per hour per unit and consume more reagents than conventional cells. Researchers at Michigan Technological University have found that baffles along the axis of a column vastly improved performance. Today only two companies in the US participate in the column flotation market, ICF Kaiser and Deister.

  3. Enhanced column flotation performance for fine coal cleaning

    Honaker, R.Q.; Mohanty, M.K. [Southern Illinois University at Carbondale, Carbondale, IL (United States). Dept. of Mining Engineering


    Experimental and theoretical results have indicated that the use of multi-stage cleaning circuits enhance the separation performance achieved by flotation columns while treating fine coal. This improvement is basically due to the excellent ability of the flotation process to float particles that contain a very small amount of hydrophobic material. Single stage treatment of a -48 mesh Illinois No. 5 coal sample found that 25% of the heavy middling in the +400 mesh size fraction were recovered to the froth concentrate, which occurred despite the use of a deep froth of 3 m. The use of a cleaner stage reduced the overall recovery of heavy middlings to approximately 10% and reduced the product ash content from 9% in the rougher stage to about 6.5% in the cleaner stage while recovering 80% of the combustible material. Subsequent treatment of the cleaner product further improved the recovery-grade curve. A similar finding was also obtained from the treatment of an Illinois No. 6 coal sample using a different flotation column. 10 refs., 9 figs., 7 tabs.

  4. Mapping collapsed columns in coal mines utilizing Microtremor Survey Methods

    Xu, P.F.; Li, C.J.; Ling, S.Q.; Zhang, Y.B.; Hou, Z.; Sun, Y.J. [Chinese Academy of Sciences, Beijing (China)


    Collapsed columns post one of the deadly safety risks to coal miners. Therefore, how to effectively map collapsed columns has become an urgent business matter for improving coal mine safety and coal production. This article documents the first application of the microtremor survey method to map geological hazards in the coal mining areas. Our results demonstrated the usefulness and effectiveness of the method, primarily due to the sensitivity of shear waves to the low-velocity collapsed columns. In the 2002 working region within the Shanxi Lu'an Zhangcun coal mine area, both the S-wave velocity structure inverted using the simple-point inversion method and the apparent S-wave velocity section obtained using the 2D microtremor profiling method clearly display the known collapsed columns. The collapsed column positions displayed in the 2D microtremor section are consistent with those seen from the tunnel, having a boundary error approximately 10 m. The microtremor method has been proved a very effective and useful geophysical tool to improve coal mining safety, because of the following characteristics: (1) high resolution, (2) no need of using the artificial source, (3) convenient and low-cost field data acquisition, and (4) little effect from local cultural structures. The microtremor survey method is also technically superior to any other geophysical method in detecting or mapping these low or high S-wave velocity anomalies. Therefore, it has a bright future in many geological and geophysical applications, such as investigation of coal seam structures and collapsed columns underneath villages.

  5. Coal desulfurization by bacterial treatment and column flotation. Final report

    Kawatra, S.K. [Michigan Technological Univ., Houghton, MI (United States)


    A review of the literature showed that bacterial leaching, using the microorganism Thiobacillus ferrooxidans, was a very effective technique for removing pyrite from coal, as it could dissolve even the finest pyrite particles without the need for expensive reagents or extreme processing conditions. Unfortunately, bacterial leaching is also rather slow, and so the initial goal of this research was to decrease the leaching time as much as possible. However, this still left the bacteria needing approximately a week to remove half of the pyritic sulfur, and so a faster technique was sought. Since it had been reported in the literature that T. ferrooxidans could be used to depress the flotation of pyrite during froth flotation of coal, this was investigated further. By studying the recovery mechanisms of coal-pyrite in froth flotation, it was found that pyrite was being recovered by entrainment and by locking to coal particles, not by true flotation of hydrophobic pyrite. Therefore, no pyrite depressant could be of any significant benefit for keeping pyrite out of the coal froth product, and it was much more important to prevent entrainment from occurring. Countercurrent flotation columns were invented to essentially eliminate entrainment effects, by washing the froth and reducing mixing of the froth and tailings products. Existing flotation columns tend to be quite simple, and in order to give reasonable product quality they must be very tall (typically 30--45 feet). As a result, they have difficulty in handling the high froth volumes which occur in coal flotation, and are awkward to install in existing plants. The bulk of this project therefore concentrated on developing an improved coal flotation column, and testing it under actual plant conditions.

  6. A comparison study of column flotation technologies for cleaning Illinois coal. Technical report, September 1--November 30, 1993

    Honaker, R.Q.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering


    The objectives of this research project are to optimize the performance of six commercially available column technologies for the treatment of Illinois Basin coal fines and to compare their performance on the basis of the recovery-grade curve and column throughput capacity. A statistically-designed experimental program will be conducted to optimize the critical operating performance values of each flotation column. The operating values suggested by the vendor will be used as the center point of the design. The ultimate recovery-grade curve and-the maximum throughput capacity for each column will be determined by conducting further tests using the optimum operating parameter values. During this reporting period, the flotation columns that were not already present were purchased and received. Installation of all the flotation columns was completed with the exception of the Packed-Column which is presently being mounted. A total of 25 fifty-five gallon drums of Illinois No. 5 flotation feed coal ({minus}100 mesh) was collected at a local preparation plant to be used as the feed for the comparison tests. A complete characterization of this coal sample will be conducted during the next reporting period.

  7. Experimental validation of pulsed column inventory estimators

    Beyerlein, A.L.; Geldard, J.F. (Clemson Univ., SC (United States)); Weh, R. (Gesellschaft fuer Nuklear-Service mbH, Hannover (Germany)); Eiben, K.; Dander, T. (Wiederaufbereitungsanlage Karlsruhe Betriebsgesellschaft mbH (WAK), Eggenstein-Leopoldshafen (Germany)); Hakkila, E.A. (Los Alamos National Lab., NM (United States))


    Near-real-time accounting (NRTA) for reprocessing plants relies on the timely measurement of all transfers through the process area and all inventory in the process. It is difficult to measure the inventory of the solvent contractors; therefore, estimation techniques are considered. We have used experimental data obtained at the TEKO facility in Karlsruhe and have applied computer codes developed at Clemson University to analyze this data. For uranium extraction, the computer predictions agree to within 15% of the measured inventories. We believe this study is significant in demonstrating that using theoretical models with a minimum amount of process data may be an acceptable approach to column inventory estimation for NRTA. 15 refs., 7 figs.

  8. Converter slag-coal cinder columns for the removal of phosphorous and other pollutants.

    Yang, Jian; Wang, Su; Lu, Zhibo; Yang, Jian; Lou, Shanjie


    A mixture of converter slag and coal cinder as adsorbent for the removal of phosphorous and other pollutants was studied in the paper. The maximum P adsorption capacity, pH of solution, contact time and initial phosphate concentration were evaluated in batch experiments for the two materials firstly. The data of P sorption were best fitted to Langumir equation, and the maximum adsorption capacities of converter slag and coal cinder were 2.417 and 0.398 mg P/g, respectively. The pH of solutions with converter slag and coal cinder changed dramatically with time and closed to 8 in 8h, and the influence of initial pH on phosphate removal by coal cinder was more significant than by converter slag. Phosphate removal rate by converter slag decreased with increase of initial phosphate concentrations. Subsequently, two flow-through columns (Column 1#, V(converter slag):V(coal cinder)=1:5; Column 2#, V(converter slag):V(coal cinder)=1:3) were operated for the removal of phosphorous and other pollutants from the effluents of a vermifilter for nearly eleven months. Results indicated the average removal efficiency of total phosphorus, dissolved phosphorus, COD and NH(4)(+)-N by Column 1# were 44%, 56%, 31% and 67%, and by Column 2# were 42%, 54%, 24% and 57%, respectively. Column 1# had higher removal efficiency for P and other pollutants.

  9. A comparison study of column flotation technologies for cleaning Illinois coal. [Quarterly] technical report, December 1, 1993--February 28, 1994

    Honaker, R.Q.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering


    The objectives of this research project are to optimize the performance of six commercially available column technologies for the treatment of Illinois Basin coal fines and to compare their performance on the basis of the recovery-grade curve and column throughput capacity. A statistically-designed, experimental program will be conducted to optimize the critical operating performance values of each flotation column. During the previous reporting period, construction and installation of the six flotation columns were completed. The flotation feed sample that will be used for the tests in this investigation was collected from a coal preparation plant treating the Illinois No. 5 seam coal. During this reporting period, the flotation feed sample was characterized on a size-by-size basis for its ash, total sulfur, and BTU content. A release analysis was also conducted to obtain the best possible recovery versus product grade curve that can be achieved by a froth flotation process for the treatment of the Illinois No. 5 flotation feed sample. Experiments were initiated on the Jameson Cell. The preliminary results indicate that the Jameson Cell achieves a separation performance that is close to the release data. The experimental program on the Jameson Cell and the other flotation technologies will be performed during the next reporting period.

  10. Experimental Testing Of Partially Encased Composite Beam Columns

    Ehab M. Hanna


    Full Text Available The past few decades have seen outstanding advances in the use of composite materials in structural applications. There can be little doubt that, within engineering circles, composites have revolutionized traditional design concepts and made possible an unparalleled range of new and exciting possibilities as viable materials for construction. In addition to the well-known advantages of composite columns, partially encased composite columns offered simplified beam-to-column connection as well as reduced or omitted shuttering thus achieved more cost effective construction. Some companies have patented these new types of partially encased composite column made of light welded steel shapes; moreover, the Canadian Institute of Steel construction CISC has recognized and codified this type of columns. In This paper, Partially Encased Composite Beam Columns is introduced; experimental studies are made on five partially encased beam columns to investigate the behavior of eccentrically loaded partially encased composite columns using different parameters.

  11. Pico-nano bubble column flotation using static mixer-venturi tube for Pittsburgh No. 8 coal seam

    Peng Felicia F.; Yu Xiong


    The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of pico and nano bubbles in a flotation column. Fully embraced by those high numbers of tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surfaces. The results of column flotation of Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height flotation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as frother. Design of the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions for maximum recovery at a specified grade. The effect of independent variables on the responses has been explained. Combustible material recovery of 85–90% at clean coal product of 10–11%ash is obtained from feed of 29.6%ash, with a much-reduced amount of frother and collector than that used in conventional column flotation. The column flotation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of particle size ranges, minus 75 lm and 300–600 lm, respectively, for better recovery.

  12. Beneficiation of an Indian non-coking coal by column flotation

    N.Vasumathi; T.V.Vijaya Kumar; S.Ratchambigai; S.Subba Rao; S.Prabhakar; G.Bhaskar Raju


    Beneficiation of non-coking coal is gaining ground in India.It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses.For special applications such as the fuel for integrated gasification combined cycle plant (IGCC),the ash content in the coal should preferably be below 15 %.Indian coals are characterized by high inter-grown ash content mainly due to ‘drift origin’ of Gondwana formation in Permian age.This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals.A noncoking coal sample of vitrinite type from India was ground to 44 tm (d80) and subjected to column flotation to improve its quality.The non-coking coal analyzing 34.6 % ash,26.2 % volatile matter,1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters,namely,froth depth,superficial feed velocity and superficial air velocity.The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.

  13. Science Column: Reconstruction: The Experimental Side of Digital Forensics

    Fred Cohen


    Full Text Available Many in digital forensics seem to forget that the science part of digital forensics means experimentation and that implies a whole lot of things that most practitioners never learned.(see PDF for full column

  14. Recovery of fine coal from waste streams using advanced column flotation

    Groppo, J.G.; Parekh, B.K. (Kentucky Univ., Lexington, KY (United States). Center for Applied Energy Research)


    The overall objective of this program is to evaluate the application of an advanced physical separation technique, namely Ken-Flote'' column flotation to recover clean coal with minimum sulfur and ash content at greater than 90 percent combustible recovery from two Illinois coal preparation plant fine waste streams. The project will optimize various operating parameters with particular emphasis on fine bubble generating devices and reagent packages to enhance the rejection of liberated ash and pyritic sulfur. During this contract period, column flotation testing was completed on the flotation feed slurry obtained from the Kerr-McGee Galatia Preparation Plant. The column flotation tests were conducted using three different bubble generating devices: Static, gas saver and foam jet spargers. Each of these devices was tested with three different frothers and various column operating variables to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. In general, the column flotation provided a clean coal containing about 4--6 percent ash at combustible recovery ranging from 88 to 92 percent while pyrite rejection was 70 to 75 percent. Flotation tests were also conducted on a slurry sample obtained from The Ziegler {number sign}26 Preparation Plant in Sesse, Illinois. Base-line flotation testing was completed using batch flotation to identify optimum reagent addition. Column flotation of the Ziegler slurry provided a clean coal containing 4--6 percent ash with a combustible recovery of 90--95 percent and pyrite rejection of 60--67 percent. Efforts are in progress in installing a 6-inc. I.D. pilot column at the Ziegler {number sign}26. 9 figs.

  15. Recovery of fine coal from waste streams using advanced column flotation

    Groppo, J.G.; Parekh, B.K.


    The overall objective of this program is to evaluate the application of an advanced physical separation technique, namely Ken-Flote'' column flotation to recover clean coal with minimum sulfur and ash content at greater than 90 percent combustible recovery from two Illinois coal preparation plant fine waste streams. This project will optimize various operating parameters with particular emphasis on fine bubble generating devices and reagent packages to enhance to rejection of liberated ash and pyritic sulfur. During this contract period, column flotation testing was conducted on the flotation feed slurry obtained from the Kerr-McGee Galatia Preparation Plant. The column flotation tests were conducted using three different bubble generating devices: static, gas saver and foam jet spargers. Each of these devices was tested with three different frothers and various column operating variables to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. In general, the column flotation provided a clean coal containing about 4--6 percent ash at combustible recovery ranging from 88 to 92 percent. 10 figs.

  16. Confined High Strength Concrete Columns: An Experimental Study

    Jagannathan Saravanan


    Full Text Available Problem statement: An experimental study on GFRP confined high strength concrete columns has been carried out with a view to evaluate its performances under uni-axial compression in terms of load and deformation capacity. Approach: High strength concrete columns strengthened with different configuration and stiffness of GFRP wraps were tested under axial compression until failure. Their response evaluated at different load levels. Results: The test results clearly indicated GFRP wrapped high strength concrete columns exhibit enhances performance. Conclusion: The study concluded that the three GFRP materials attempted UDC GFRP provided the maximum benefit with respect to load and deformation.


    Dwi Retno Nurotul Wahidiyah


    Full Text Available Application of activated zeolite (ZAA as molecular sieve to separate compounds of coal tar from vaccum fractional distillation, have been done. The size of zeolite was 10-20 mesh and used as solid phase in column chromatography with length of 30 cm. The first step of the research was coal pyrolisis and the product (tar was distillated by fractional column and vaccum system at reduced pressure 44 cmHg and maximum temperature at 200 oC. The distillate from this procedure was flowed to the column chromatography of zeolite (ZAA. The compound absorbed by zeolite was eluted with varying solvents, i.e: CCl4, acetone and ethanol. Each fraction was then analyzed by gas chromatography. The results showed, zeolite have a capability to separate the compounds of tar and it tends to absorb medium hydrocarbon. The nonpolar eluent [CCl4] gives the better result in eluting tar compound than polar (ethanol or medium polar eluents (acetone.   Keywords: zeolite, coal tar, column chromatography

  18. On-line testing of a horizontally-baffled flotation column in an operating coal-cleaning plant

    Eisele, T.C.; Kawatra, S.K. [Michigan Technological Univ., Houghton, MI (United States). Dept. of Metallurgical and Materials Engineering


    A horizontal-baffle arrangement has been developed to prevent excessive axial mixing in flotation columns. These baffles have been shown in previous work to improve the grade/recovery performance of both a laboratory-scale column and a pilot-scale column. In this paper, results are given for continuous on-line operation of the pilot-scale baffled column in a commercial coal-cleaning plant. These results show its ability to operate for extended periods without plugging, to produce a consistent-quality product even while the feed quality was fluctuating, and to remove much of the pyritic sulfur from the coal.

  19. A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 March 1995--31 May 1995

    Honaker, R.Q. [Southern Illinois Univ., Carbondale, IL (United States); Reed, S. [Kerr-McGee Coal Corp., Oklahoma City, OK (United States)


    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an extensive separation performance comparison between a pilot-scale Floatex Density Separator (18{times}18-inch) and an existing spiral circuit has been conducted at Kerf-McGee Coal Preparation plan for the treatment of nominally {minus}16 mesh coal. The results indicate that the Floatex is a more efficient separation device (E{sub p}=0.12) than a conventional coal spiral (E{sub p}=0.18) for Illinois seam coals. In addition, the treatment of {minus}100 mesh Illinois No. 5 fine coal from the same plant using Falcon concentrator, column flotation (Packed-Column) and their different combinations was also evaluated. For a single operation, both Falcon concentrator and column flotation can produce a clean coal product with 90% combustible recovery and 5% ash content. In the case of the combined circuit, column flotation followed by the Falcon achieved a higher combustible recovery value (about 75%) than that obtained by the individual units while maintaining an ash content less than 3%.

  20. RC Columns Strengthened with Novel CFRP Systems: An Experimental Study

    Annalisa Napoli


    Full Text Available This paper presents an experimental study undertaken to investigate the seismic behavior of full scale square (300 mm × 300 mm reinforced concrete (RC columns strengthened with novel systems employing carbon fiber-reinforced polymers (CFRP wraps. Experimental tests were carried out by subjecting specimens to a constant axial load and a cyclically reversed horizontal force applied in displacement control. Results have allowed for investigating the influence of the used strengthening systems on the specimens’ performance in terms of flexural strength and ductility as well as on the exhibited failure modes. The effectiveness of the studied techniques is also evaluated by comparing the performance of tested specimens with that of companion columns strengthened with alternative CFRP systems investigated in a previous experimental campaign.

  1. A comparison study of column flotation technologies for cleaning Illinois coal. Final technical report, September 1, 1993--November 30, 1994

    Honaker, R.Q.; Paul, B.C.


    Six commercially-available column technologies were compared on the basis of their separation performance, throughput capacity and operational characteristics for treating Illinois Basin coal fines. The flotation column technologies included in this study were the Jameson Cell, Flotaire, Turboair, Packed-Column, Microcel and the Canadian Column. The coal samples treated in this study were a {minus}100 mesh flotation feed slurry, a {minus}40 mesh coal, and a refuse pond coal sample. This investigation found that the Packed Column, Jameson Cell, and Microcel are the best flotation columns for cleaning the Illinois Basin coals treated in this study. The Packed-Column was found to provide superior selectivity, although requiring the highest amount of air and frother concentration. The superior performance is believed to be related to the extensive reflux action and selective detachment mechanism that are more prevalent in the Packed-Column due to its unique ability to support a full froth column. Among the conventional open columns, the Microcel provided the best selectivity, most likely due to its lower aeration requirement which results in a more plug-flow environment within the cell. Both the Packed-Column and the Microcel appeared to have nearly equal throughput capacities. The Jameson Cell, which also has a relatively high throughput capacity, was found to require the least amount of frother while supplying a self-inducing air system. Another important finding of this investigation is that the traditional release analysis procedure is inadequate for predicting the optimum performance of advanced froth flotation processes and, thus, requires further investigation.

  2. Nonequilibrium stage modelling of dividing wall columns and experimental validation

    Hiller, Christoph; Buck, Christina; Ehlers, Christoph; Fieg, Georg


    Dealing with complex process units like dividing wall columns pushes the focus on the determination of suitable modelling approaches. For this purpose a nonequilibrium stage model is developed. The successful validation is achieved by an experimental investigation of fatty alcohol mixtures under vacuum condition at pilot scale. Aim is the recovery of high purity products. The proposed model predicts the product qualities and temperature profiles very well.

  3. Group separation and analysis of a carbon disulfide-soluble fraction from Shenfu coal by column chromatography

    DING Ming-jie; WEI Xian-yong; ZONG Zhi-min; ZONG Ying; OUYANG Xiao-dong; HUANG Yao-guo; ZHOU Lei; ZHENG Yu-xuan; ZHOU Xiao; WEI Yan-bin


    A carbon disulfide-soluble fraction (CDSSF) from Shenfu coal was separated into five fractions by silica-gel column chromatography using hexane and n-hexane/ethyl acetate binary eluent. The five fractions include four clear group fractions and a nonpolar fraction. All the fractions were analyzed by GC/MS. A total of 204 compounds were detected from the original CDSSF and its further separated fractions, with 173 compounds more than those detected by studying the original CDSSF directly. The results demonstrate a clear group separation by column chromatography in coal organic components and a more accessibility to coal components compared with the solvent extraction only.

  4. Study on the genesis of karstic collapse column and characteristics of high resolution seismic data in one coal field

    ZHANG Shao-hong; LIN Chang-rong


    On the standpoint of the disaster prevention from water inrush,discussed the genesis and geologic condition of karstic collapse column in one coal field,analyzed the geophysical characteristics of karstic collapse column by using high resolution 3D seismic data.It shows the effective result of the technology of high resolution 3D seismic prospecting in the exploration of the karstic collapse column,and presents some prediction methods and prevention measures.

  5. Fine coal flotation plant waste comparison--column vs. sub-a cells

    Ehrlinger, H.P. III.


    The objective of this project was to compare results from a small commercially sized Deister Flotaire column flotation cell with the subaeration cells at Kerr-McGee's Galatia plant during side by side testing of feed splits from the same sources. Typical cell criteria for both cells are included in the appendix. The project involved the activities of three organizations: the Kerr-McGee Coal Corporation, the Deister Concentrator Company, and the Illinois State Geological Survey. Their roles were as follows: Kerr-McGee installed the Deister column with sample splitter and tailings volume measuring cell in the Galatia Coal Preparation Plant to treat a representative split of their flotation feed; Deister provided a 30 inch diameter {times} 35{prime} high Deister Flotaire Column Flotation Cell capable of treating nominally one ton per hour or slightly over 1% of the plant feed. Deister additionally provided the sample splitter and the tailings volume measuring cell. ISGS personnel worked with both companies on the installation, conducted laboratory tests to direct the early plant test reagent practice, attended all of the plant runs cutting representative samples of feed, measuring slurry and reagent flows, preparing samples and writing reports.

  6. Coal fly ash interaction with environmental fluids: Geochemical and strontium isotope results from combined column and batch leaching experiments

    Brubaker, Tonya M; Stewart, Brian W; Capo, Rosemary C; Schroeder, Karl T; Chapman, Elizabeth C; Spivak-Birndorf, Lev J; Vesper, Dorothy J; Cardone, Carol R; Rohar, Paul C


    The major element and Sr isotope systematics and geochemistry of coal fly ash and its interactions with environmental waters were investigated using laboratory flow-through column leaching experiments (sodium carbonate, acetic acid, nitric acid) and sequential batch leaching experiments (water, acetic acid, hydrochloric acid). Column leaching of Class F fly ash samples shows rapid release of most major elements early in the leaching procedure, suggesting an association of these elements with soluble and surface bound phases. Delayed release of certain elements (e.g., Al, Fe, Si) signals gradual dissolution of more resistant silicate or glass phases as leaching continues. Strontium isotope results from both column and batch leaching experiments show a marked increase in {sup 87}Sr/{sup 86}Sr ratio with continued leaching, yielding a total range of values from 0.7107 to 0.7138. For comparison, the isotopic composition of fluid output from a fly ash impoundment in West Virginia falls in a narrow range around 0.7124. The experimental data suggest the presence of a more resistant, highly radiogenic silicate phase that survives the combustion process and is leached after the more soluble minerals are removed. Strontium isotopic homogenization of minerals in coal does not always occur during the combustion process, despite the high temperatures encountered in the boiler. Early-released Sr tends to be isotopically uniform; thus the Sr isotopic composition of fly ash could be distinguishable from other sources and is a useful tool for quantifying the possible contribution of fly ash leaching to the total dissolved load in natural surface and ground waters.

  7. Experimental Study on CFRP Strengthened Cold Formed Channel Columns

    Sreedhar Kalavagunta


    Full Text Available Cold-formed steel members usually display local-global buckling interaction which strongly effects the structural strength of columns. Through strengthening web of the members this buckling can be controlled to some extent. In this investigation, Carbon Fibre Reinforced Polymers (CFRP is used for strengthening cold formed steel channel member. This paper presents compression tests of cold-formed plain and CFRP strengthened steel channel section columns. This paper also proposes a design method based on Direct Strength Method provisions specified in American Iron and Steel Institute (AISI, for determining the axial compression strength. Results obtained from the proposed design method are compared with experimental test data and are found to be in good agreement.

  8. Recovery of fine coal from waste streams using advanced column flotation. Annual report, September 1, 1990--August 31, 1991

    Groppo, J.G.


    The advanced flotation techniques, namely column flotation, have shown potential in obtaining a low ash, low pyritic sulfur fine size clean coal. The overall objective of this program is to evaluate applicability of an advanced flotation technique, `Ken-Flote` column to recover clean coal with minimum mineral matter content at greater than 90 percent combustible recovery from two Illinois preparation plant waste streams. Column flotations tests were conducted on the flotation feed obtained from the Kerr-McGee Galatia and Ziegler No. 26 plants using three different bubble-generating devices: sparger, gas saver and foam jet. Each of these devices was tested with three different frothers and various column-operating variable to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. For the Galatia slurry, the column provided a clean coal containing 5 percent ash, 0.48 percent pyritic sulfur at combustible recovery averaging 90 percent. In other words, about 90 percent ash and about 75 percent pyritic sulfur rejection were attained for the Galatia slurry. Pilot plant studies on this slurry basically obtained results similar to the laboratory studies. For the Ziegler No. 26, slurry column flotation provided a clean coal containing about 5 percent ash, 0.44 percent pyritic sulfur at more than 90 percent combustible recovery. The ash and pyrite sulfur rejection was about 85 percent and 65 percent, respectively.

  9. Attenuation of heavy metals by geosynthetics in the coal gangue-filled columns.

    Wang, Ping; Hu, Zhenqi; Wang, Peijun


    In the subsided areas backfilled with coal gangue, an issue of continuing environmental concern is the migration of hazardous metals to the subsurface soil and groundwater. As an effective isolation material, geosynthetics have been scarcely applied into mining areas reclamation of China. This paper describes research aimed at characterizing the behaviours of different geosynthetics in the leaching columns filled with coal gangues. Four types of geosynthetics were selected: fibres needle-punched nonwoven geotextiles, high-density polyethylene, needle-punched Na-bentonite geosynthetic clay liner (GCL-NP) and Na-bentonite geosynthetic-overbited film. Heavy metals were significantly attenuated and by monitoring aqueous solutions in the whole percolation period, negative correlation was found between pH value and concentration of heavy metals. Generally, GCL-NP showed comparatively better effects on attenuating the migration of heavy metals. According to the meta-analysis of heavy metals present in the leachates and retained in the columns, geosynthetics have good capabilities of sorption and retardation, which can delay the breakthrough time of heavy metals and retard the accumulation in the subsurface. Future research will use X-ray diffraction and micro-imaging (electron microprobe and scanning electron microscopy) to further explain retention mechanisms.

  10. Determination of phenylenediamine isomers in hair dyes by coal cinders micro-column extraction and MEKC.

    Wu, Yiwei; Jiang, Feng; Chen, Lin; Zheng, Jing; Deng, Zhenli; Tao, Qing; Zhang, Jing; Han, Lijuan; Wei, Xiaoshu; Yu, Aimin; Zhang, Haili


    A new micellar electrokinetic chromatography (MEKC) method using beta-cyclodextrins (β-CDs) and 1-butyl-3-methylimidazolium hexafluorophosphates (ionic liquids) as additives was successfully developed for determination of para-, meta-, and ortho-phenylenediamines isomers (p-P, m-P, and o-P) in hair dyes. To improve the sensitivity of the MEKC-UV, a simple and cheap flow injection (FI) technique using a micro-column packed with coal cinders (the by-products from combustion in a boiler) as solid-phase extractant was also investigated. In the presence of 20 mmol L(-1) phosphates at pH 5.5, addition of 12 mmol L(-1) ionic liquids and 8 mmol L(-1) β-CDs greatly improved the separation efficiency. The three analytes could be quantitatively adsorbed by coal cinders, and desorbed readily with 0.15 mL of 0.01 mol L(-1) NaOH. Under the optimum conditions, an enrichment factor (EF) of 33.3 was obtained, and determination limits of p-P, m-P, and o-P were 1.97 × 10(-7), 0.99 × 10(-7), and 0.61 × 10(-7) mol L(-1), respectively. The adsorption capacities of the coal cinders micro-column for p-P, m-P, and o-P were all 1.20 mg g(-1). The presented procedure was successfully applied to the determination of p-P, m-P, and o-P in hair dyes with satisfactory results.

  11. Experimental study on pollution emission from combustion of blended coals

    Li Yonghua; Chen Hongwei; Zhen Zhi; Liu Jizhen; Feng Zhaoxing; Dong Jianxun [North China Electric Power University, Baoding (China)


    The pollution brought by NOx and SOx produced by coal combustion is getting recognition by each country in the world. This paper adopts an experimental method, selects four kinds of lignite and three kinds of soft coal that are mainly used by some power plant and reports a study of the pollution emission characteristics of component and blended coals. The test rig is introduced from Canada with a capacity of 640 MJ/h with a complete milling system and flue gas online analysis system. The study focuses on the influence of oxygen concentration, pulverized coal fineness and pulverized coal nitrogen content on the pollution emission. The study is useful for achieving clean combustion in large power plants. 5 refs., 4 figs., 7 tabs.

  12. Experimental study of coal topping process in a downer reactor

    Wang, J.G.; Lu, X.S.; Yao, J.X.; Lin, W.G.; Cui, L.J. [Chinese Academy of Science, Beijing (China). Inst. of Processing Engineering


    Experiments were carried out in a downer reactor integrated in a circulating fluidized bed combustor to examine the performance of the coal topping process. The effects of reaction temperature and coal particle size on the product distribution and their compositions were determined. The experimental results show that an increase in temperature will increase the yields of gas and liquid product, and the liquid yield decreases with the increase in coal particle size. The experiments exhibit an optimal condition for the liquid product. When the pyrolysis temperature is 660{sup o}C and coal particle size is less than 0.2-8 mm, the yield of light tar (hexane-soluble fraction) reaches 7.5 wt % (dry coal basis). The light tar is composed of acid groups (57.1 wt %), crude gasoline (aliphatics) (12.9 wt %), aromatics (21.4 wt %), and polar and basic groups (8.6 wt %). The experiments indicate that the coal topping process is a promising technology for partially converting coal into liquid fuels and fine chemicals.

  13. Column flotation

    Kohmuench, J.N.; Norrgran, D.A.; Luttrell, E.; Luttrell, G.H. [Virginia Tech. (United States)


    Over the last decade, column flotation has been recognised in the industry to be most efficient and economical means of recovering fine coal while maximizing product grade. When designed properly, flotation columns provide a high combustible recovery while maintaining a low product ash. The paper looks at the benefits of using column flotation for fine coal recovery. 2 refs., 5 figs.


    Paul C.K. Lam; Isaac K. Gamwo; Dimitri Gidaspow


    The objective of this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed and is appended in this report. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The details are presented in the attached paper titled ''CFD Simulation of Flow and Turbulence in a Slurry Bubble Column''. This phase of the work is in press in a referred journal (AIChE Journal, 2002) and was presented at the Fourth International Conference on Multiphase Flow (ICMF 2001) in New Orleans, May 27-June 1, 2001 (Paper No. 909). The computed time averaged particle velocities and concentrations agree with Particle Image Velocimetry (PIV) measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. To better understand turbulence we studied fluidization in a liquid-solid bed. This work was also presented at the Fourth International Conference on Multiphase Flow (ICMF 2001, Paper No. 910). To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV


    Paul Lam; Dimitri Gidaspow


    The objective if this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The computed time averaged particle velocities and concentrations agree with PIV measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. This phase of the work was presented at the Chemical Reaction Engineering VIII: Computational Fluid Dynamics, August 6-11, 2000 in Quebec City, Canada. To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV technique. The results together with simulations will be presented at the annual meeting of AIChE in November 2000.

  16. Fine coal flotation of plant waste: An in-plant comparison---columns vs. sub-a cell

    Ehrlinger, H.P.; Lytle, J.M.; Kohlenberger, L.; Rapp, D.M. (Illinois State Geological Survey, Champaign, IL (USA)); Stephenson, J.; Zipperian, D. (Deister Machine Co., Inc., Fort Wayne, IN (USA)); Sterner, R.; Norris, D. (Kerr-McGee Corp., Oklahoma City, OK (USA))


    The objective of this project is to compare the flotation effectiveness of the column flotation and the sub-aeration technology to clean very fine ({minus}100 mesh) coal in the waste streams of coal washing plants. The recent developments in the flotation of fine coal from the waste streams of coal washing plants has been favorable. Good concentrate grades along with a high recovery of energy content have been achieved while rejecting a large percentage of the ash forming minerals and pyrite. However, comparative data of columns vs. sub-aeration cells is not available from a single plant. This project was developed to install a small commercial size Deister Column beside the existing sub-aeration flotation cells at Kerr-McGee's Galatia Plant so that a comparison of the flotation results can be made. A representative split of the fines which normally goes to sub-aeration cells can be diverted without reagent, to the column for continuous side by side flotation testing over an extended period. This quarter additional tests were conducted with reagent variations including xanthate and sodium silicate. The xanthate is a sulfide collector to float the pyritic sulfur with the coal. This information is a guide as to the degree of liberation of pyrite in the coal. The sulfur content in the concentrate increased during these tests indicating the pyrite is partially liberated in the flotation feed. Sodium silicate was added in two tests. While preliminary in the nature, these tests showed lower ash content for the same Btu recovery. 6 tabs.

  17. Experimental Study on Coal-Breaking Pressure for Compressed Air


    Based on lab model experiments and through the limit analysis, the theoretical formula of calculauoncoal-breaking pressure with compressed air was derived. The experimental result shows that blasting pressure mustexceed 84.0 MPa to break coal with compressive strength of 13.2 MPa. The research provides an important theoretical basis for the design of airshooting mining and industrial tests.

  18. A fine coal circuitry study using column flotation and gravity separation. Technical report, September 1--November 30, 1994

    Honaker, R.Q. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering; Reed, S. [Kerr-McGee Coal Corp., Oklahoma City, OK (United States)


    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. The gravity/flotation circuits will be compared based on their optimum separation performance which will consider ash and total sulfur rejection and energy recovery as well as the probable error (E{sub p}) value obtained from washability analyses. During this reporting period, multi-stage treatment using the Falcon concentrator was conducted on a refuse pond ({minus}100 mesh) coal sample and a {minus}28 mesh run-of-mine coal sample. The results suggest that the Falcon concentrator can make an ideal separation for either sample in a single process. Recleaning was found to improve product grade, however, recovery was reduced sharply. In addition, the groups involved with the in-plant testing of the Floatex Hydrosizer met and organized the test plan which will be conducted at Kerr-McGee`s Galatia preparation plant during the next reporting period. Coal samples for the circuitry tests will be collected during, this time period.

  19. New experimental technique to determine coal self-ignition duration

    Xinhai ZHANG; Guang XI


    An artificial neural network (ANN) model was adopted to simulate the relationship between self-ignition duration and sulfur content, ash content, oxygen con-sumption rate, carbon monoxide as well as carbon dioxide generation rate of coal at different temperatures of self heating process. The data from spontaneous combustion experiments were used for ANN training to obtain the connection strength between nerve cells. An oil-bath pro-grammed temperature experiment device was designed and the experimental condition and the size of the test tube were determined for testing the oxygen consumption and the gases generation rate of coal during self-heating process. The sulfur content, the ash content and the data from the oil-bath experiment were taken as ANN inputs to calculate the experiment self-ignition duration of coal. Compared with spontaneous combustion experiment, less than 1% of coal sample and 10% of time are required with an error of less than 3 days to test self-ignition duration of coal.

  20. A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 December 1994--28 February 1995

    Honaker, R.Q. [Southern Illinois Univ., Carbondale, IL (United States); Reed, S. [Kerr-McGee Coal Corp., Oklahoma City, OK (United States)


    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an in-plant Box-Behnken test program of the Floatex hydrosizer has been conducted at Kerr-McGee`s Galatia preparation plant. The results have shown that the Floatex hydrosizer can be successfully used to reject most of coarser ({plus}100 mesh) pyrite and mineral matter in the coal stream to the plant. With a single operation, ash rejection of 63% and total sulfur rejection of 43% have been achieved while maintaining a combustible recovery as high as 90.5%. A long term duration test under the optimum operating conditions determined from Box-Behnken test results has also been conducted. The feed samples for the following enhanced gravity - column flotation studies, which will be carried out in the next reporting period, have been collected.

  1. Valorization of bituminous coal pulps using column flotation; Valorisation de fines de charbon bitumineux par flottation en colonnes

    Gursu, G.; Hicyilmaz, C. [Universite du Moyen-Orient, Ankara (Turkey); Bilgen, S. [Universite de Mersin (Turkey)


    Washing tests were performed with 5 x 5 x 200 cm{sup 3} laboratory flotation columns on bituminous coal pulps from Zonguldak (Turkey) containing 47.52% of ash. The final product contains 10% of ash with a 73.52% recovery. A re-washing of this concentrate allows to obtain a final product with 5.88% of ash and a 59.27% recovery. Abstract only. (J.S.)

  2. Experimental Study of the Ignition of Single Drops of Coal Suspensions and Coal Particles in the Oxidizer Flow

    Vershinina, K. Yu.; Glushkov, D. O.; Kuznetsov, G. V.; Strizhak, P. A.


    An experimental study has been made of the process of ignition of single drops of water-coal and organic water-coal suspensions and coal particles heated by the oxidizer flow. The low-temperature (400-600°C) regime of the initiation of combustion of commensurate (from 1 to 3 mm) drops of water-coal and organic water-coal suspensions and coal particles has been considered. With the use of a high-speed (up to 105 frames/s) video camera and Tema Automative software, the influence of the oxidizer temperature, the gas flow velocity, the size of suspension fuel drops, and the coal particle size on the conditions and integral characteristics of the induction period has been determined. The ignition delay times and the duration of the combustion process of the investigated fuel samples have been established. The features of the stages of stable low-temperature initiation of combustion have been determined.

  3. Experimental study on influence of coal structural anisotropy to gas permeation

    QIAO Yan-zhen


    Based on "true triaxial coal rock permeability of coal sample test system",the permeability under different gaspressure to coal specimen in bedding plane and the vertical bedding directions are tested.The results show that coal structuralanisotropy has a greater impact on gas permeability properties,differences in experimental coal permeability are roughly oneorder of magnitude.In view of the differences of the gas flow characteristics in the coal bedding plane and vertical bedding,established series and parallel choked flow model of coal sample gas seepage,and made a theoretical analysis to the influencesof the bedding structure to gas permeability properties.

  4. Fine coal flotation of plant waste: An in-plant comparison - columns vs. sub-A cell

    Ehrlinger, H.P. III; Lytle, J.M.; Kohlenberger, L.; Rapp, D.M. (Illinois State Geological Survey, Champaign, IL (United States)); Stephenson, J.; Zipperian, D. (Deister Machine Co., Inc., Fort Wayne, IN (United States)); Sterner, R.M.; Norris, D. (Kerr-McGee Corp., Oklahoma City, OK (United States))


    The objective of this project is to compare the flotation effectiveness of the column flotation and the sub-aeration technology to clean very fine ({minus}100 mesh) coal in the waste streams of coal washing plants. Good concentrate grades along with a high recovery of energy content have been achieved while rejecting a large percentage of the ash forming minerals and pyrite. However, comparative data of columns vs. sub-aeration cells is not available from a single plant. This project was developed to install a small commercial size Deister Column beside the existing sub-aeration flotation cells at Kerr-McGee's Galatia Plant so that a comparison of the flotation results can be made. A representative split of the fines which normally goes to sub-aeration cells can be diverted without reagent, to the column for continuous side by side flotation testing over an extended period. The Deister Column was installed during the quarter along with the sampling system and tailings volume measuring apparatus. Parts of several weeks were spent in assuring that realistic goals could be obtained. During the de-bugging period it was found that water pressure and air pressure within the plant was not constant due to cleanup hoses which were on the same fresh water line to assure constant water and air pressure to the column during testing periods. Most of the shakedown testing was completed in April and May. Preliminary tests have been run in which high grade concentrates have been made but with low Btu recoveries. Additional tests with increased reagent rates are planned to increase Btu recoveries and will be reported at the Contractors Conference and in the final report. 24 figs., 1 tab.

  5. Experimental study on supercritical CO2 adsorption on coals from Upper Silesian coal Basin

    Weishauptová, Zuzana; Přibyl, Oldřich; Sýkorová, Ivana


    of drill cores from exploration boreholes in the Bohemian part of the Upper Silesian Basin, and were characterized by a narrow range of the degree of coalification and extremely different petrographic composition. A positive correlation has been found between the equilibrium moisture in the coal samples and the total abundance of oxygen functional groups determined by FTIR. The experimental isotherm data were fitted partly by the modified Langmuir sorption isotherm, partly by the modified Dubinin-Radushkevich sorption isotherm. The calculated values of sorption capacities were compared. After recalculation to the mineral-matter free basis, a positive trend has been observed in the studied samples in the dependence of the sorption capacity on the micropore volume, as well as a positive trend in the dependence on percentage of vitrinite and collotelinite, which forms a major part of vitrinite. On the contrary, a negative trend has been found in the dependence on inertinite percentage.

  6. Experimental and analytical behavior of strengthened reinforced concrete columns with steel angles and strips

    Khalifa, Essam S.; Al-Tersawy, Sherif H.


    The need of strengthening reinforced concrete columns, due to loss of strength and/or stiffness, is an essential requirement due to variation of the loads and environmental conditions applied on these columns. Steel jackets around the reinforced concrete (RC) columns are usually made by means of steel plates covering all over the column surface area. For the value of engineering purposes, another technique was developed using steel angles at the corners of the RC columns connected with discrete steel strips. In this paper, an experimental program is designed to evaluate the improvement in load-carrying capacity, stiffness and ductility of strengthened RC columns, concomitant with steel angles and strips. Despite of prevailing a substantially increased loading capacity and strength a pronounced enhancement in ductility and stiffness has been reported. A need for experimental test results with low value of concrete strength to mimic the local old-age structures condition that required strengthening in local countries. Seven columns specimens are tested to evaluate the strength improvement provided by steel strengthening of columns. The method of strengthened steel angles with strips is compared with another strengthening technique. This technique includes connected and unconnected steel-casing specimens. The observed experimental results describe load-shortening curves, horizontal strains in stirrups and steel strips, as well as description of failure mode. The extra-confinement pressure, due to existence of steel cage, of the strengthened RC column can be also observed from experimental results. The code provisions that predict the load-carrying capacity of the strengthened RC composite column has a discrepancy in the results. For this reason, an analytical model is developed in this paper to compare the code limit with experimental observed results. The proposed model accounts for the composite action for concrete confinement and enhancement of the local buckling

  7. Buckling and Fracture Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    Berggreen, Christian; Carlsson, Leif A.; Avilés, F.


    An experimental and numerical study of in-plane compression of foam core sandwich columns with implanted trough width face/core debond is presented. Experiments were conducted for columns with two different face thicknesses over different cores and debond lengths. The debonded region was monitore...

  8. Buckling and Fracture Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    Berggreen, Christian; Carlsson, Leif A.; Avilés, F.


    An experimental and numerical study of in-plane compression of foam core sandwich columns with implanted trough width face/core debond is presented. Experiments were conducted for columns with two different face thicknesses over different cores and debond lengths. The debonded region was monitore...

  9. Experimental Study of Hydrogasification of Lignite and Subbituminous Coal Chars

    Stanisław Gil


    Full Text Available The experimental facility for pressure hydrogasification research was adapted to the pressure of 10 MPa and temperature of 1300 K, which ensured repeatability of results and hydrogen heating to the process temperature. A hydrogasification reaction of chars produced from two rank coals was investigated at temperatures up to 1173 K, pressures up to 8 MPa, and the gas flow rates of 0.5–5 dmn3/min. Reactivity of the “Szczerców” lignite char was found to be slightly higher than that of the subbituminous “Janina” coal char produced under the same conditions. A high value of the char reactivity was observed to a certain carbon conversion degree, above which a sharp drop took place. It was shown that, to achieve proper carbon conversion, the hydrogasification reaction must proceed at a temperature above 1200 K.

  10. Experimental study on the variation law of coal temperature during excavation in coal mines

    Yi-Shan PAN; Lian-Man XU; Zhong-Hua LI; Guo-Zhen LI


    By testing the temperature of the coal and the stress of the working surface,we got the variation law of coal temperature and coal stress during the excavation.The result shows that the activities of mining affect the coal temperature,the fluctuation of coal temperature and the coal stress is synchronous.During the smooth change of crustal stress,the coal temperature basically keeps unchanged,when the dynamic phenomenon appears,the coal temperature changes,as well the coal stress.Therefore,we can use the online coal temperature monitoring system to test the coal temperature of the working surface continuously,and it can provide basic information for forecasting coal mine power disaster before it happens.

  11. Experimental Research and Mathematical Modelling for Coal Reburning in Furnace

    XIANG Jun; SU Sheng; SUN Lu-shi; SUN Xue-xin; ZHANG Zhong-xiao; ZHU Ji-mu


    Reburning technology is one of the most cost-effective NOx reduction strategies for coal combustion systems. In this paper, a nitric oxide submodel incorporated into a comprehensive coal combustion model was developed for predicting NOx reduction in a 93 kW laboratory-scale coal combustion furnace by reburning. This NO submodel, including reburning mechanism, requires the solution of only two transport equations to model the behavior of NO reduction in the reburning process. A number of experiments have been performed in the same furnace, and the experimental data obtained from the optimized reburn configuration was used to validate the model. Measurements and predictions both show above 50% reduction of NO emissions for the optimized reburning process. Profile comparisons show that the predicted temperature and oxygen concentration match well with the measurements, and the general trend of predicted NO concentration is very similar to that measured. The results of this study show that the present nitric oxide submodel depicts quite well the observed behaviour of NO annihilation in the reburning process. It is expected that this usable and computationally economic model represents a useful tool to simulate the gaseous fuel reburning process for the researchers concerned with practical combustors.


    姜志伟; 黄波; 曹炅


    Emission of large amount of SO2 from combustion of high sulfur coal causes serious envjsonmental pollution. Pre-combustion desulfurization of bigh sulfur coal has become a necessity. This paper reports test results of fine coal desuifurtzation with different flotation technology and the effect of pyrite depressant. Test work showed that when the coal sample from Zhong Liang Shah was processed with a Free Jet Flotation Column its pyritic sultur content was reduced from 3.08% to 0. 84%, with 72.22% recovery ofcombustible matter in clean coal. The concept of Desulfurlzatlon Efficiency Index Eofor comprehensive evaluation of dcsuifurlzation process is proposed, which is defined as the product of the ratio of sulfur content reduction of clean coal and the recovery of combustible matters.

  13. Experimental study on the angle of repose of pulverized coal

    Wei Wang; Jiansheng Zhang; Shi Yang; Hai Zhang; Hairui Yang; Guangxi Yue


    An experimental study on the angle of repose(AoR)of pulverized coal with different particle sizes and different moisture contents(MC)was conducted.Three different measurement methods,free-base piling,fixed-base piling and sliding,were used.The data were analyzed by one-way and two-way analysis of variance.The results showed that the AoRs of pulverized coal with particle sizes smaller than 150 μm were in the range of 30-50°.The characterization of the flowability of pulverized coal was some cohesiveness or true cohesiveness.The increase of MC will increase AoR and thus decrease the flowability of the powder.However,the particle size effect is bifurcated.Below a critical size,the decrease of particle size decreases the flowability; while above the critical size,the decrease of particle size increases the flowability.It was found that the value of the critical size strongly depends on the powder density.Moreover,the AoR dependence on particle size could be linked with the Geldart's particle classification.The critical size at the turning point is on the boundary between Group A and Group B in Geldart's classification diagram.Based on the experimental results,there is no significant cross interaction between particle size and MC.The AoRs measured by free-base method and fixed-base method are close,but both remarkably smaller than that measured by the sliding method.

  14. Experimental simulation and numerical analysis of coal spontaneous combustion process at low temperature

    文虎; 徐精彩; 葛岭梅


    The characteristic of coal spontaneous, combustion includes oxidative property and exothermic capacity. It can really simulate the process of coal spontaneous combustion to use the large-scale experimental unit loading coal ! 000 kg. According to the field change of gas concentration and coal temperature determined through experiment of coal self-ignite at low temperature stage, and on the basis of hydromechanics and heat-transfer theory, some parameters can be calculated at different low temperature stage, such as, oxygen consumption rate, heat liberation intensity. It offers a theoretic criterion for quantitatively analyzing characteristic of coal self-ignite and forecasting coal spontaneous combustion. According to coal exothermic capability and its thermal storage surroundings, thermal equilibrium is applied to deduce the computational method of limit parameter of coal self-ignite. It offers a quantitative theoretic criterion for coal self-ignite forecasting and preventing. According to the measurement and test of spontaneous combustion of Haibei coal, some token parameter of Haibei coal,spontaneous combustion is quantitatively analyzed, such as, spontaneous combustion period of coal, critical temperature, oxygen consumption rate, heat liberation intensity, and limit parameter of coal self-ignite.

  15. Experimental simulation and numerical analysis of coal spontaneous combustion process at low temperature*

    WEN Hu; XU Jing-cai; GE Ling-mei


    The characteristic of coal spontaneous combustion includes oxidative p roperty and exothermic capacity. It can really simulate the process of coal spon taneous combustion to use the large-scale experimental unit loading coal 1 000 kg. According to the field change of gas concentration and coal temperature determi ned through experiment of coal self-ignite at low temperature stage, and on the basis of hydromechanics and heat-transfer theory, some parameters can be calcul at ed at different low temperature stage, such as, oxygen consumption rate, heat li beration intensity. It offers a theoretic criterion for quantitatively analyzing characteristic of coal self-ignite and forecasting coal spontaneous combustion . According to coal exothermic capability and its thermal storage surroundings, t hermal equilibrium is applied to deduce the computational method of limit parame ter of coal self-ignite. It offers a quantitative theoretic criterion for coal s elf-ignite forecasting and preventing. According to the measurement and test of spontaneous combustion of Haibei coal, some token parameter of Haibei coal spont aneous combustion is quantitatively analyzed, such as, spontaneous combustion pe riod of coal, critical temperature, oxygen consumption rate, heat liberation int ensity, and limit parameter of coal self-ignite.

  16. Coal miner's pneumoconiosis: epidemiological and experimental approaches

    Amoudru, C.


    A historical review is presented showing the belated recognition of coal miner's pneumoconiosis as a discrete pathological state, a fact due to a lack of experimental pathological research. The distribution of the disease in France was studied. Its incidence has decreased among active miners, but the number of cases has increased as a result of increased longevity of miners. Physiological and pathological concepts of the disease are discussed, which has become a post-professional disease with delayed radiological symptoms, which frequently entails chronic cor pulmonale, and which varies in incidence from one mining region to another. Lines of ongoing experimental research, which take account of new work in epidemiology and in dust analysis as well as recent biological studies on man are summarized. 29 references.

  17. Experimental engineering section off-gas decontamination facility's fractionator column: installation and performance

    Gilliam, T. M.; Fowler, V. L.; Inman, D. J.


    A detailed description of the third column recently installed in the Experimental Engineering Section Off-Gas Decontamination Facility (EES-ODF) is presented. The EES-ODF is being used to provide engineering-scale experiments (nominal gas and liquid flows of 5 scfm and 0.5 gpm, respectively) in the development of the Krypton Absorption in Liquid CO/sub 2/ (KALC) process. A detailed discussion of the column's construction is provided. This discussion includes the peripherals associated with the column, such as refrigeration, heat exchangers, instrumentation, etc. The compressibility of Goodloe packing (the packing in the other columns) and the possible reduced throughput due to this compression have revealed the desirablility of a random (i.e., noncompressible) packing. Toward this end, the third column is packed with a new random packing (PRO-PAK). A preliminary comparison between this packing and the woven wire mesh packing (Goodloe) used in the other two columns has been made. Experiments comparing the throughput capacity indicate that the PRO-PAK packing has approximately 60% the capacity of Goodloe for a CO/sub 2/ system. When used as a fractionator or stripper with the basic O/sub 2/-Kr-CO/sub 2/ KALC system, the PRO-PAK column produced HTU values less than or equal to the GOODLOE columns under similar operating conditions.

  18. Experimental study on ignition characteristics of pulverized coal under high-temperature oxygen condition

    Liu, G. W.; Liu, Y. H.; Dong, P.


    The high-temperature oxygen ignition technology of pulverized coal, which can replace the oil gun and achieve oil-free pulverized coal ignition by mixing the high- temperature oxygen and the pulverized coal stream directly, was proposed and a relevant ignition experimental system was built. The ignition characteristics of pulverized coal under high-temperature oxygen condition were investigated: the ignition process was described and analyzed, the influence of relevant parameters on the pulverized coal stream ignition were obtained and analyzed. The results showed: when the oxygen heating temperature is over 750 °C, the pulverized coal stream could be ignited successfully by high-temperature oxygen; increasing the pulverized coal concentration, primary air temperature and oxygen volume flow rate or decreasing the primary air velocity is helpful for the ignition and combustion of the pulverized coal stream.

  19. Experimental study of a rotating packed bed distillation column

    J. V. S. Nascimento


    Full Text Available The purpose of this work was to study the mass transfer performance of rotating packed beds applying the "Higee" process. The operations were carried out with the n-hexane/n-heptane distilling system at atmospheric pressure and under total reflux conditions. The rotating speed could be varied between 300 and 2500 rpm, which provided centrifugal forces from 5 to 316 times the Earth's gravity. The effects of concentration, vapor velocity, rotating speed and packing type (two different Raschig ring sizes and structured wire mesh packing on mass transfer behavior were analyzed. Experimental results showed that the mass transfer coefficient depends on the liquid flow rates and rotating speed. The equipment had high separation efficiency in a reduced bed volume.

  20. The principle analysis of methane explosion suppressed by water column curtain in coal mining

    ZHOU Tong-ling(周同龄); HE Xue-qiu(何学秋); YANG Yi(杨艺)


    The principles of fine water mist explosion-extinguishing system was introduced. The defects of current systems were analyzed. The concept of a new water column curtain and the explosion-extinguishing mechanism were given. Using water column curtain to suppress methane explosion in experiment pipes was conducted. The photos were written with schlieren photograph system. The results of experiment show that the effect is perfect.

  1. Prevention of spontaneous combustion in coal stockpiles : Experimental results in coal storage yard

    Fierro, V.; Miranda, J.L.; Romero, C.; Andrés, J.M.; Arriaga, A.; Schmal, D.; Visser, G.H.


    The spontaneous ignition of coal stockpiles is a serious economic and safety problem. This paper deals with oxidation and spontaneous combustion of coal piles laid in coal storage yard and the measures to avoid the heat losses produced. Investigations on self heating were carried out with five test

  2. Prevention of spontaneous combustion in coal stockpiles : Experimental results in coal storage yard

    Fierro, V.; Miranda, J.L.; Romero, C.; Andrés, J.M.; Arriaga, A.; Schmal, D.; Visser, G.H.


    The spontaneous ignition of coal stockpiles is a serious economic and safety problem. This paper deals with oxidation and spontaneous combustion of coal piles laid in coal storage yard and the measures to avoid the heat losses produced. Investigations on self heating were carried out with five test

  3. Experimental Confirmation of Water Column Natural Resonance Migration in a BBDB Device

    Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gunawan, Budi [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Holmes, Brian [HMRC Univ. of Cork (Ireland)


    Experiments were conducted with a Backward Bent Duct Buoy (BBDB) oscillating water column wave energy conversion device with a scaling factor of 50 at HMRC at University College Cork, Ireland. Results were compared to numerical performance models. This work experimentally verified the migration of the natural resonance location of the water column due to hydrodynamic coupling for a floating non- axisymmetric device without a power conversion chain PCC present. In addition, the experimental results verified the performance model with a PCC of the same non- axisymmetric device when both floating and grounded.

  4. Development and design of a multi-column experimental setup for Kr/Xe separation

    Garn, Troy G. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    As a precursor to FY-15 Kr/Xe separation testing, design modifications to an existing experimental setup are warranted. The modifications would allow for multi-column testing to facilitate a Xe separation followed by a Kr separation using engineered form sorbents prepared using an INL patented process. A new cooling apparatus capable of achieving test temperatures to -40° C and able to house a newly designed Xe column was acquired. Modifications to the existing setup are being installed to allow for multi-column testing and gas constituent analyses using evacuated sample bombs. The new modifications will allow for independent temperature control for each column enabling a plethora of test conditions to be implemented. Sample analyses will be used to evaluate the Xe/Kr selectivity of the AgZ-PAN sorbent and determine the Kr purity of the effluent stream following Kr capture using the HZ-PAN sorbent.

  5. Multi-Column Experimental Test Bed for Xe/Kr Separation

    Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lyon, Kevin Lawrence [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)ry


    Previous research studies have shown that INL-developed engineered form sorbents are capable of capturing both Kr and Xe from various composite gas streams. The previous experimental test bed provided single column testing for capacity evaluations over a broad temperature range. To advance research capabilities, the employment of an additional column to study selective capture of target species to provide a defined final gas composition for waste storage was warranted. The second column addition also allows for compositional analyses of the final gas product to provide for final storage determinations. The INL krypton capture system was modified by adding an additional adsorption column in order to create a multi-column test bed. The purpose of this modification was to investigate the separation of xenon from krypton supplied as a mixed gas feed. The extra column was placed in a Stirling Ultra-low Temperature Cooler, capable of controlling temperatures between 190 and 253K. Additional piping and valves were incorporated into the system to allow for a variety of flow path configurations. The new column was filled with the AgZ-PAN sorbent which was utilized as the capture medium for xenon while allowing the krypton to pass through. The xenon-free gas stream was then routed to the cryostat filled with the HZ-PAN sorbent to capture the krypton at 191K. Selectivities of xenon over krypton were determined using the new column to verify the system performance and to establish the operating conditions required for multi-column testing. Results of these evaluations verified that the system was operating as designed and also demonstrated that AgZ-PAN exhibits excellent selectivity for xenon over krypton in air at or near room temperature. Two separation tests were performed utilizing a feed gas consisting of 1000 ppmv xenon and 150 ppmv krypton with the balance being made up of air. The AgZ-PAN temperature was held at 295 or 253K while the HZ-PAN was held at 191K for both

  6. Hydrocarbon-oil encapsulated bubble flotation of fine coal using 3-in. ID flotation column. Technical progress report for the eleventh quarter, April 1--June 30, 1993

    Peng, F.F.


    There are four modes of the collector dispersion techniques. They are (1) direct liquid additions and stirring, (2) ultrasonic energy collector dispersion, (3) atomized collector dispersion, and (4) gasified collector transported in air stream. Among those collector dispersion techniques, the technique using the gasified collector transported in air phase can be used to enhance the flotation performance with substantial reduction in collector usage and selectivity, compared to the flotation using direct liquid addition (and mechanical agitation) technique. In this phase of study, two modes of collector addition techniques including gasified collector transported in gas phase and direct collector addition techniques were applied in the column flotation to demonstrate the selectivity of utilizing the hydrocarbon-oil encapsulated air bubbles in the fine coal flotation process. The 1-in. ID flotation column was used to scale-up to 3-in. ID flotation column. The initial starting point to operate the 3-in ID flotation column were determined using both 1-in. and 3-in. flotation columns based on the three phases of work plans and experiment design. A 3-in. flotation column was used to evaluate two modes of collector dispersion and addition techniques on the recovery and grade of fine coals using various ranks of coal.

  7. Experimental and modelling investigations of tracer transport in variably saturated agricultural soil of Thailand: Column study

    Tulaya Masipan


    Full Text Available Tracer (Bromide movement through the unsaturated agricultural soil was investigated in soil columns. Two tracer column experiments, with a diameter of 7 cm and a depth of 25 cm, were vertically homogeneous packed with sandy loam and then carried out to investigate bromide (Br− transport under different water contents (at steady flow condition. One soil column (Column 1 represents the unsaturated agricultural soil in dry season (with water content ranging from 0.23 to 0.26 and the other (Column 2 represents the soil in wet season (water content from 0.24 to 0.35. Bromide samples were periodically collected by vacuum tubes inserted at 6.25 cm equally spaced intervals (e.g., 6.25, 12.5, 18.75 and 25 cm along the length of the column and the effluent collected at the end of the column. The observed breakthrough curves (BTCs of bromide in both columns represented a relative smooth and sigmodal curves at different distances (sampling ports. Dispersivity (α, cm for sandy loam at different locations was numerically estimated by curve fitting the experimental data with HYDRUS-1D. The α can be well described by the convection–dispersion equation and these values derived from Column 1 (ranging from 0.37 to 0.98 cm are more than those from Column 2 (0.25–0.59. Moreover, the α in both columns increases with the travel distance due to the scale-dependent effect. Furthermore, the α values were plotted on a log–log scale against travel distances and they yield empirical power law relationships with an excellent correlation (α = 0.102 (L0.697, R2 = 0.999 and α = 0.086 (L0.579, R2 = 0.963 for Column 1 and 2, respectively.

  8. The experimental verification on the shear bearing capacity of exposed steel column foot

    Xijin, LIU


    In terms of the shear bearing capacity of the exposed steel column foot, there are many researches both home and abroad. However, the majority of the researches are limited to the theoretical analysis sector and few of them make the experimental analysis. In accordance with the prototype of an industrial plant in Beijing, this paper designs the experimental model. The experimental model is composed of six steel structural members in two groups, with three members without shear key and three members with shear key. The paper checks the shear bearing capacity of two groups respectively under different axial forces. The experiment shows: The anchor bolt of the exposed steel column foot features relatively large shear bearing capacity which could not be neglected. The results deducted through calculation methods proposed by this paper under two situations match the experimental results in terms of the shear bearing capacity of the steel column foot. Besides, it also proposed suggestions on revising the Code for Design of Steel Structure in the aspect of setting the shear key in the steel column foot.

  9. Experimental and Modeling Investigation of Coal Gasification in a Fluidized Bed Reactor

    CuiLin; ShenYouting; 等


    This paper presents a new approach to study the process of coal gasification.Non-linear programming techniques are used to determine the value of the model parameters that depends on coal species and experimental conditions and thus minimize the difference between experimental results and model predictions.Model predictions being in good agreement with the experimental results show that this method of combining model with experiment is effective for modeling complex processes.

  10. An experimental study on an oscillating loop heat pipe consisting of three interconnected columns

    Özdemir, Mustafa


    This paper presents some experimental results of an extensive research on a novel oscillating heat pipe. The heat pipe is formed of three interconnected columns as different from the pulsating heat pipe designs. The dimensions of the heat pipe considered in this study are large enough to neglect the effect of capillary forces. Thus, the self-oscillation of the system is driven by the gravitational force and the phase lag between the evaporation and condensation processes. The overall heat transfer coefficient is found to be approximately constant irrespective of heat load for the experimental cases considered. The results are also compared with the previously published data by other investigators for water as the working fluid and for the same heat input range. The experimental data for the time variation of the liquid column heights and the vapor pressure are correlated algebraically, convenient for practical uses.

  11. Experimental study of the stress effect on attenuation of normally incident P-wave through coal

    Feng, Junjun; Wang, Enyuan; Chen, Liang; Li, Xuelong; Xu, Zhaoyong; Li, Guoai


    The purpose of this study is to experimentally investigate the stress effect on normally incident P-wave attenuation through coal specimens. Laboratory tests were carried out using a Split Hopkinson pressure bar (SHPB) system, and a modified method was proposed to determine the quality factor (Q) of P-waves through coal specimens. Larger quality factor denotes less energy attenuated during P-wave propagating through coal. Experimental results indicate that the quality factor and stress (σ) within coal specimens are positively correlated. The P-wave propagation through coal specimens causes crack closure at the beginning of the coal fracture process in SHPB tests, an innovative model was thus proposed to describe the relationship between the crack closure length and the dynamic stress induced by P-wave. Finally, the stress effect on P-wave attenuation through coal was quantitatively represented by a power function Q = a(c-bσ)- 6, and the material constants a, b, and c were determined as 1.227, 1.314, and 0.005, respectively. The results obtained in this study would be helpful for engineers to estimate seismic energy attenuation and coal mass instability in coal mines.

  12. Experimental Investigation of Modified Polypropylene Shell-Tube Column Using Humidification-Dehumidification Desalination Process


    The polypropylene tubes with surface modification were installed in a baffled shell-tube column to conduct the thermally coupled humidification and dehumidification desalination process. The effects of several operating parameters (feed water temperature, water flow rate, carrier air flow rate, and external steam flow rate) on the productivity and thermal efficiency of this column were investigated experimentally. The results show that the feed water temperature has a positive effect on the productivity and thermal efficiency, while the flow rates of external steam, feed water, and carrier air should be optimized within the ranges of 0.006-0.020 kg· m-2· s-1, 0.005-0.015 kg· m-1· s-1, and 0.7-1.3 kg· m-2· s-1,respectively; the flow rates of feed water and carrier air are greatly controlled by the wetting state of the tubes. In comparison with the previous desalination column installing the coppery tubes, the present column can reach nearly the same production capacity of distilled water, which demonstrates the feasibility of applying such a plastic column to the humidification and dehumidification desalination process.

  13. Simulation and Experimental Study of Arc Column Expansion After Ignition in Low-Voltage Circuit Breakers

    MA Qiang; RONG Mingzhe; WU Yi; XU Tiejun; SUN Zhiqiang


    The dynamicprocess of arc pressure and corresponding arc column expansion, which is the main feature after arc ignition and has a significant effect on the breaking behaviour of low -voltage circuit breakers, is studied. By constructing a three dimensional mathematical model of air arc plasma and adopting the Control Volume Method, the parameters of arc plasma including temperature and pressure axe obtained. The variations of pressure field and temperature field with time are simulated. The result indicates that there are six stages for the process of arc column expansion according to the variation of pressure in arc chamber. In the first stage, the maximal pressure locates in the region close to cathode, and in the second stage the maximal pressure shifts to the region close to the anode. In the third stage, the pressure difference between the middle of arc column and the ambient gas is very large, so the arc column begins to expand apparently. In the fourth stage, the pressure wave propagates towards both ends and the maximal pressure appears at the two ends when the pressure wave reaches both sidewalls. In the fifth stage, the pressure wave is reflected and collides in the middle of the arc chamber. In the last stage, the propagation and reflection of pressure wave will repeat several times until a steady burning state is reached. In addition, the experimental results of arc column expansion, corresponding to the arc pressure variation, are presented to verify the simulation results.

  14. Nitrogen Injection To Flush Coal Seam Gas Out Of Coal: An Experimental Study

    Zhang, Lei; Aziz, Naj; Ren, Ting; Nemcik, Jan; Tu, Shihao


    Several mines operating in the Bulli seam of the Sydney Basin in NSW, Australia are experiencing difficulties in reducing gas content within the available drainage lead time in various sections of the coal deposit. Increased density of drainage boreholes has proven to be ineffective, particularly in sections of the coal seam rich in CO2. Plus with the increasing worldwide concern on green house gas reduction and clean energy utilisation, significant attention is paid to develop a more practical and economical method of enhancing the gas recovery from coal seams. A technology based on N2 injection was proposed to flush the Coal Seam Gas (CSG) out of coal and enhance the gas drainage process. In this study, laboratory tests on CO2 and CH4 gas recovery from coal by N2 injection are described and results show that N2 flushing has a significant impact on the CO2 and CH4 desorption and removal from coal. During the flushing stage, it was found that N2 flushing plays a more effective role in reducing adsorbed CH4 than CO2. Comparatively, during the desorption stage, the study shows gas desorption after N2 flushing plays a more effective role in reducing adsorbed CO2 than CH4.

  15. Experimental research on fire resistance of circular steel tube column filled with steel-reinforced high-strength concrete


    Circular steel tube filled with steel-reinforced high-strength concrete is a new model of composite column design.The fire resistance of this composite column was investigated experimentally.One circular steel tube column filled with steel-reinforced high-strength concrete and one circular steel tube column filled with high- strength concrete were tested under axial load and fire.The test results show that the axial deformations of both kinds of the composite columns under the same load level...


    路春美; 程世庆; 邵延玲; 张晔


    Through a lot of experiments, a new kind of stove using horizontal combustion technique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and efficiency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0.5R and dust concentration is below 90mg/m3 . The stove's combustion efficiency reaches 90%, sulfur fixing efficiency is 60%, and CO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.

  17. Experimental study of hollow rectangular bridge column performance under vertical and cyclically bilateral loads

    Han, Qiang; Du, Xiuli; Zhou, Yihui; Lee, George C.


    To investigate the seismic performance of hollow reinforced concrete (RC) bridge columns of rectangular cross section under constant axial load and cyclically biaxial bending, five specimens were tested. A parametric study is carried out for different axial load ratios, longitudinal reinforcement ratios and lateral reinforcement ratios. The experimental results showed that all tested specimens failed in the flexural failure mode and their ultimate performance was dominated by flexural capacity, which is represented by the rupture/buckling of tensile longitudinal rebars at the bottom of the bridge columns. Biaxial force and displacement hysteresis loops showed significant stiffness and strength degradations, and the pinching effect and coupling interaction effect of both directions severely decrease the structural seismic resistance. However, the measured ductility coefficient varying from 3.5 to 5.7 and the equivalent viscous damping ratio varying from 0.19 and 0.26 can meet the requirements of the seismic design. The hollow RC rectangular bridge columns with configurations of lateral reinforcement in this study have excellent performance under bidirectional earthquake excitations, and may be considered as a substitute for current hollow RC rectangular section configurations described in the Guideline for Seismic Design of Highway Bridges (JTG/T B02-01-2008). The length of the plastic hinge region was found to approach one sixth of the hollow RC rectangular bridge column height for all specimen columns, and it was much less than those specified in the current JTG/T. Thus, the length of the plastic hinge region is more concentrated for RC rectangular hollow bridge columns.

  18. Experimental Study of Coal and Gas Outbursts Related to Gas-Enriched Areas

    Tu, Qingyi; Cheng, Yuanping; Guo, Pinkun; Jiang, Jingyu; Wang, Liang; Zhang, Rong


    A coal and gas outburst can lead to a catastrophic failure in a coal mine. These outbursts usually occur where the distribution of coal seam gas is abnormal, commonly in tectonic belts. To study the effects of the abnormal distribution of this gas on outbursts, an experimental apparatus to collect data on simulated coal seam outbursts was constructed. Experiments on specimens containing discrete gas-enriched areas were run to induce artificial gas outbursts and further study of these outbursts using data from the experiment was conducted. The results suggest that more gas and outburst energy are contained in gas-enriched areas and this permits these areas to cause an outburst easily, even though the gas pressure in them is lower. During mining, the disappearance of the sealing effect of a coal pillar establishes the occurrence conditions for an outburst. When the enriched gas and outburst energy in the gas-enriched area is released suddenly, a reverse unloading wave and a high gas pressure gradient are formed, which have tension effects on the coal. Under these effects, the fragmentation degree of the coal intensifies and the intensity of the outburst increases. Because a high gas pressure gradient is maintained near the exposed surface and the enriched energy release reduces the coal strength, the existence of a gas-enriched area in coal leads to a faster outburst and the average thickness of the spall is smaller than where is no gas-enriched area.

  19. Experimental uses of short pulse radar in coal seams

    Coon, J.B.; Fowler, J.C.; Schafers, C.J.


    Radar tests in coal mines conducted by the Mining Research Division of Conoco and Ensco, Inc. are presented. The purpose was to determine penetration distances and reflection ranges which are obtainable with currently available short pulse radar. The tests were conducted in mines operated by Consolidation Coal Co. during 1977 and 1978. The first test examined penetration distances, velocity of propagation, and attenuation versus frequency for a large coal pillar. These tests also showed the definite polarization effects which had previously been measured in coal. The second series of tests was designed to show maximum reflection distances for a radar with a centre frequency of 100 MHz. Using common-depth-point reflection techniques, a ten-fold CDP line obtained reflections from distances in excess of 50 ft. This was the first time such techniques have been used with short pulse radar. The final series of tests was conducted to locate a six-inch borehole within a coal pillar. The radar system located the hole quickly and easily even though it was 20 ft into the pillar. These tests show it is possible to use short pulse radar as a hazard detection device in coal mines. The major limitations with a current equipment are that it cannot be used in return air and it is not easily transported in the mine. As a result of these tests, Conoco and Ensco have started a development program to build and test a truly portable mine radar system capable of operation in return air.

  20. Experimental investigation of axially loaded steel fiber reinforced high strength concrete-filled steel tube columns

    卢亦焱; 李娜; 李杉; 梁鸿骏


    An experimental study on the compressive behavior of steel fiber reinforced concrete-filled steel tube columns is presented. Specimens were tested to investigate the effects of the concrete strength, the thickness of steel tube and the steel fiber volume fraction on the ultimate strength and the ductility. The experimental results indicate that the addition of steel fibers in concrete can significantly improve the ductility and the energy dissipation capacity of the concrete-filled steel tube columns and delay the local buckling of the steel tube, but has no obvious effect on the failure mode. It has also been found that the addition of steel fibers is a more effective method than using thicker steel tube in enhancing the ductility, and more advantageous in the case of higher strength concrete. An analytical model to estimate the load capacity is proposed for steel tube columns filled with both plain concrete and steel fiber reinforced concrete. The predicted results are in good agreement with the experimental ones obtained in this work and literatures.

  1. Experimental research on combustion fluorine retention using calcium-based sorbets during coal combustion (Ⅰ)

    QI Qing-jie; LIN Zhi-yan; LIU Jian-zhong; WU Xian; ZHOU Jun-hu; CEN Ke-fa


    In order to provide experimental guide to commercial use of fluorine pollution control during coal combustion, with fluorine pollution control during coal combustion in mind, this paper proposed the theory of combustion fluorine retention technology. Feasibility of fluorine retention reaction with calcium-based fluorine retention agent was analyzed through thermo-dynamic calculation during coal combustion. By simulating the restraining and retention effects and influential factors of calcium-based sorbets on vaporized fluoride during experimental combustion using fixed bed tube furnace, the paper systematically explored the influential law of such factors as combustion temperature, retention time, and added quantities of calcium-based sorbets on effects of fluorine retention. The research result shows that adding calcium-based fluorine retention agent in coal combustion has double effects of fluorine retention and sulfur retention, it lays an experimental foundation for commercial test of combustion fluorine retention.

  2. Experimental 3-D Vector Velocity Estimation with Row-Column Addressed Arrays

    Holbek, Simon; Stuart, Matthias Bo; Jensen, Jørgen Arendt


    Experimental 3-D vector flow estimates obtained with a 62+62 2-D row-column (RC) array with integrated apodization are presented. A transverse oscillation (TO) velocity estimator is implemented on a 3.0 MHz RC array, to yield realtime 3-D vector flow in a cross-sectional scan plane at 750 frames...... rates. The flow rate measured from five cycles is 2.3 mL/stroke ± 0.1 mL/stroke giving a negative 9.7% bias compared to the pump settings. It is concluded that 124 elements are sufficient to estimate 3-D vector flow, if they are positioned in a row-column wise manner....

  3. Experimental Study on the Feasibility of Methane Drainage in Coal Seams with Compound Technique of Perforating and Fracturing

    Luo Yong; Shen Zhaowu


    Compound technique of perforating and fracturing can effectively control the perforating direction and the fracturing expansion. The feasibility of this technique used in fracturing coal seams is analyzed. In this paper, the experiments of perforating and fracturing are carried out on samples of coal and the experimental effects are satisfactory. Compound technique of perforating and fracturing is promising in coal seams.


    Zhou Ze-xuan; Tan Soon Keat


    A new kind of governing equations for water hammer based on the elastic column theory was proposed and adopted to analyse water hammer phenomenon in the pipe system with a vertical column surge chamber and water level fluctuation in the surge chamber during pressure transient. The wrongness existing in the classical governing equations for water hammer was analysed. A typical reservoir-valve pipe system was chosen as an example to verify the new governing equations numerically and experimentally. The finite difference method based on the method of characteristics was used to solve numerically the nonlinear characteristic equations. The temporal evolutions of transient volume flux and head and of water level fluctuation for various surge chamber configurations were worked out, assuming that the air in the surge chamber are compressible. The relevant experiment was conducted to verify the new governing equations and numerical method. The numerical and experimental results show that the new governing equations are valid and the conventional assumption that the pressure head at the base of a surge chamber equals that of the static head above it during pressure transient is not always valid. The surge chamber generally reises the period of transient pressure wave in pipe system, reduces the maximum pressure envelope and lifts the minimum envelope substantially. The water level fluctuation in the surge chamber was numerically and experimentally observed. Increasing the size of the surge chamber and/or decreasing the initial air pressure in the surge chamber enhance the effectiveness of the surge chamber in suppressing pressure wave.

  5. Experimental study on the seismic response of braced reinforced concrete frame with irregular columns

    Xiao, Jianzhuang; Li, Jie; Chen, Jun


    A 15-storey K-braced reinforced concrete model frame with irregular columns, i.e., T-shaped, L-shaped, as well as +-shaped columns, was constructed and tested on the six-degree-of-freedom shaking table at the State Key Laboratory for Disaster Reduction in Civil Engineering in Tongji, China. Two types of earthquake records, El-Centro wave (south-north direction) and Shanghai artifi cial wave (SHAW) with various peak accelerations and principal-secondary sequences, were input and experimentally studied. Based on the shaking table tests and theoretical analysis, several observations can be made. The failure sequence of the model structure is brace→beam→column→joints, so that the design philosophy for several lines of defense has been achieved. Earthquake waves with different spectrums not only infl uence the magnitude and distribution of the earthquake force and the storey shear force, but also obviously affect the magnitude of the displacement response. The aftershock seismic response of previously damaged reinforced concrete braced frames with irregular columns possesses the equivalent elastic performance characteristic. Generally speaking, from the aspects of failure features and drift ratio, this type of reinforced concrete structure provides adequate earthquake resistance and can be promoted for use in China.

  6. Numerical Simulation and Experimental Research on Coal Ash Collecting and Grading System

    Yuanhua Xie


    Full Text Available The grading separation of coal ash can not only increase its economic value but also decrease its pollution to environment. Based on the jet-attracting flow technology and the gas-solid two-phase flow theory, the force and motion of coal ash particles in airflow were studied firstly. Focused on single coal ash particle, Matlab software was used to simulate the force conditions and separation parameters of various diameter coal ash particles in airflow. Fluent software was used to simulate the nozzle fluidization domain shape and to determine optimal jet flux. According to the theoretical results, a coal ash collecting and grading system was developed. Using the separation efficiency as the evaluation index, the optimal experiment parameters of jet flux, attracting flux, and separation time were obtained. At last, the calculated results and experimental results of coal ash particles median diameter from the first grading separation exit under various attracting fluxes were compared. The reasons that could cause the errors were discussed. This study has significant practical meaning and application value on coal ash collecting and grading separation.

  7. Experimental investigation of liquid chromatography columns by means of computed tomography

    Astrath, D.U.; Lottes, F.; Vu, Duc Thuong;


    dispersive model (EDM) and varying the so called apparent axial dispersion coefficient. The additivity of the first and second central moments was exploited to estimate column efficiency in different regions of the column. The results showed that the columns under investigation offered a higher column...

  8. Fine coal flotation plant waste comparison--column vs. sub-a cells. Final technical report, September 1, 1990--August 31, 1991

    Ehrlinger, H.P. III


    The objective of this project was to compare results from a small commercially sized Deister Flotaire column flotation cell with the subaeration cells at Kerr-McGee`s Galatia plant during side by side testing of feed splits from the same sources. Typical cell criteria for both cells are included in the appendix. The project involved the activities of three organizations: the Kerr-McGee Coal Corporation, the Deister Concentrator Company, and the Illinois State Geological Survey. Their roles were as follows: Kerr-McGee installed the Deister column with sample splitter and tailings volume measuring cell in the Galatia Coal Preparation Plant to treat a representative split of their flotation feed; Deister provided a 30 inch diameter {times} 35{prime} high Deister Flotaire Column Flotation Cell capable of treating nominally one ton per hour or slightly over 1% of the plant feed. Deister additionally provided the sample splitter and the tailings volume measuring cell. ISGS personnel worked with both companies on the installation, conducted laboratory tests to direct the early plant test reagent practice, attended all of the plant runs cutting representative samples of feed, measuring slurry and reagent flows, preparing samples and writing reports.

  9. Co-gasification of Colombian coal and biomass in fluidized bed: An experimental study

    Jhon F. Velez; Farid Chejne; Carlos F. Valdes; Eder J. Emery; Carlos A. Londono [Universidad Nacional de Colombia, Antioquia (Colombia). Grupo de Termodinamica Aplicada y Energias Alternativas


    The main results of an experimental work on co-gasification of Colombian biomass/coal blends in a fluidized bed working at atmospheric pressure are reported in this paper. Several samples of blends were prepared by mixing 6-15wt% biomass (sawdust, rice or coffee husk) with coal. Experimental assays were carried out by using mixtures of different steams/blends (Rvc) and air/blend (Rac) ratios showing the feasibility to implement co-gasification as energetic alternative to produce fuel gas to heat and to generate electricity and the possibility of converting clean and efficiently the refuse coal to a low-heating value gas. 29 refs., 5 figs., 4 tabs.

  10. Pathways in coal thermolysis: a theoretical and experimental study with model compounds

    Ekpenyong, I.A.; Virk, P.S.


    Fundamental aspects of coal thermolysis were investigated, including how the chemical structures of aromatics, hydroaromatics, and alcohols affect their reactivities as hydrogen donors and acceptors in coal processing. The susceptibilities of substructural entities in coals to fragmentation via a number of thermal pericyclic and free radical mechanisms were probed, as were the factors governing relative reactivities within series of such coal model compounds. The theoretical part of the work applied perturbation molecular orbital (PMO) and frontier orbital theories, in conjunction with ..pi..- and pseudo-..pi.. MO's, to the study of model compound reactivity. This enabled prediction of reactivity patterns of H-donors, H-acceptors and coal-like structures as functions of their ..pi..- and sigma-bond configurations, including heteroatomic effects. Experimentally, the liquid phase reactions of the coal model compound PhOCH/sub 2/Ph (Benzyl phenyl ether, BPE) were detailed for the first time in each of four hydronaphthalene H-donor solvents in the temperature range 220/sup 0/ to 300/sup 0/C. The thermolysis of BPE exhibited a pronounced dependence on solvent structure, both with respect to product selectivities and reaction kinetics. BPE thermolysis pathways were delineated as involving (a) rearrangement, leading to isomerization, (b) hydrogenations, leading ultimately to PhOH and PhCH/sub 3/ products, and (c) addition reactions, engendering heavy products. Pathways (b) and (c) are competitive and, in each, self-reactions of BPE-derivatives vie against reactions between these and the donor solvent. Of the detailed free radical and pericyclic reaction mechanisms postulated, the latter rationalized many more facets of the BPE results than the former. The theoretical and experimental results were appraised against previous coal thermolysis literature.

  11. An experimentally constrained MHD model for a collisional, rotating plasma column

    Wright, A. M.; Qu, Z. S.; Caneses, J. F.; Hole, M. J.


    A steady-state single fluid MHD model which describes the equilibrium of plasma parameters in a collisional, rotating plasma column with temperature gradients and a non-uniform externally applied magnetic field is developed. Two novel methods of simplifying the governing equations are introduced. Specifically, a ‘radial transport constraint’ and an ordering argument are applied. The reduced system is subsequently solved to yield the equilibrium of macroscopic plasma parameters in the bulk region of the plasma. The model is benchmarked by comparing these solutions to experimental measurements of axial velocity and density for a hydrogen plasma in the converging-field experiment MAGPIE and overall a good agreement is observed. The plasma equilibrium is determined by the interaction of a density gradient, due to a temperature gradient, with an electric field. The magnetic field and temperature gradient are identified as key parameters in determining the flow profile, which may be important considerations in other applications.

  12. Experimental Investigation of the Hysteretic Behavior of Wide-Flange Steel Columns under High Axial Load and Lateral Drift Demands

    Lignos, Dimitrios; Cravero, Julien; Elkady, Ahmed Mohamed Ahmed


    This paper discusses the findings from a large-scale experimental program that characterized the hysteretic behavior of typical steel wide-flange columns in steel moment-resisting frames (MRFs). The test specimens were tested in a cantilever configuration with a fixed point of inflection. The main testing parameters included various lateral and axial loading histories, the applied axial compressive load and the local slenderness of the cross-section. It is shown that (a) steel columns subject...

  13. Influence of liquid water on coalbed methane adsorption: An experimental research on coal reservoirs in the south of Qinshui Basin

    SANG Shuxun; ZHU Yanming; ZHANG Jing; ZHANG Xiaodong; ZHANG Shiyin


    Using Isothermal Adsorption/Desorption System Model IS-100 and Electrohydraulic Servo Rock System Model MTS815 as the main apparatuses and collecting samples from the major coal reservoirs in the south of Qinshui Basin, a hot point region of coalbed methane exploration, the paper carries out systematical comparisons of the isothermal adsorption experimental data for injection water coal sampies, equilibrium moisture samples and dry coal samples,probes and establishes an experimental method of injection water coal sample preparation and isothermal experiment to simulate real reservoir conditions, and then summaries the experimental regulations and discusses the mechanism of liquid water influencing coal methane adsorption. Results of the experiment indicate that: The Langmuir volume of injection water coal samples is notably larger than that of equilibrium moisture samples, as well as larger than or equivalent to that of dry coal samples; the Langmuir pressure of injection water coal samples is the highest, the next is equilibrium moisture samples, while the dry samples is the lowest, of which the experimental results of injection water samples to simulate real reservoir conditions are more close to the fact.Under the conditions of in-position reservoirs, liquid water in coals has evident influence on methane adsorption ability of coal matrix, which can increase the adsorbability of coal and make the adsorption regulation fit to Langmuir model better.Its major reason is the increase of wetting coal matrix adsorbability. The above experimental results overthrow the conventional cognition that liquid water has no influence on coalbed methane adsorption, which may lead to an improvement of the coalbed methane isothermal adsorption experimental method and of the reliability of coalbed methane resource evaluation and prediction.

  14. Experimental Research on Desulfurization of Fine Coal Using an Enhanced Centrifugal Gravity Separator

    TAO You-jun; LUO Zhen-fu; ZHAO Yue-min; TAO Daniel


    A desulphurization experimental study under the effects of compounding physical force fields has been described for < 0.5 mm fine particles of high sulfur coal. A statistical test using the Box-Behnken Design of experiments was conducted to evaluate the effects of individual operating variables and their interactions on desulfurization of fine coal using an enhanced centrifugal gravity separator. A model describing the relation between desulphurization efficiency of pyrite sulfur and different operating variables has been designed. The interactions between different factors on the pyrite sulfur desulphurization efficiency have been analysed. The optimal test conditions for desulfarization are extracted from the Design-Expert 6.0 software. Finally, the advantage of centrifugal gravity separation for fine coal is pointed out.

  15. Uncertainty Analysis using Experimental Design Methods for Assessing CO2 Sequestration and Coal Bed Methane Production Potential of Subbituminous Coals of the Nenana Basin, Interior Alaska

    Dixit, N.; Ahmadi, M.; Hanks, C.; Awoleke, O.


    Naturally fractured, unmineable coal seam reservoirs are attractive targets for geological sequestration of CO2 because of their high CO2-adsorption capacities and possible cost offsets from enhanced coal bed methane production (ECBM). In this study, we have investigated CO2 sequestration and CH4 production potential of the subbituminous Healy Creek Formation coals through preliminary sensitivity analyses, experimental design methods and fluid flow simulations. Our primary sensitivity analyses indicated that the total cumulative volumes of CO2 sequestered and CH4 produced from the Healy Creek coals are mostly sensitive to bottomhole injection pressure, coal matrix porosity, fracture porosity and permeability, and coal volumetric strain. The results of Plackett-Burman experimental design were used to further constrain the most influential reservoir parameters and generate proxy models for probabilistic reservoir forecasts. Our probabilistic estimates for the mature, subbituminous Healy Creek coals in the entire Nenana basin indicate that it is possible to sequestrate between 0.87 TCF (P10) and 0.2 TCF (P90) of CO2 while producing between 0.29 TCF (P10) and 0.1 TCF (P90) of CH4 at the end of 20-year forecast. Our study demonstrated application of experimental design methods and Monte Carlo analysis in reducing these uncertainties in reservoir properties and quantifying their effect on reservoir performance. In addition, the results of fluid flow scenarios show that the CO2 sequestration through a primary reservoir depletion method is the most effective way to inject CO2 in the coals of the Nenana basin. Including a horizontal well instead of the vertical well resulted in relatively high average gas production rates and subsequent faster production decline. Our CO2 buoyancy scenario suggested that the effect of CO2 buoyancy and the nature of the caprock should be considered when identifying potential geologic sites for CO2 sequestration and in CO2 storage capacity

  16. The ZECOMIX experimental facility for hydrogen and power generation from coal

    A. Calabro; P. Deiana; P. Fiorini; S. Stendardo; G. Girardi [ENEA - Italian Agency for New Technologies, Rome (Italy). Energy and Environment Energy and Plants Division


    The Zecomix project, conceived by ENEA in the framework of Italian National Hydrogen Project, is aimed at studying an integrated process that produces both hydrogen and electricity from coal, with zero emissions and very high efficiency. The Zero Emission Coal Mixed technology concept combines two different systems: the Zero Emission Coal gasification and the Zero Emission Combustion Technology based on Hydrogen-fuelled internal combustion turbine cycle. The key element is the integration of a gasification process, characterized by coal hydrogasification technology and carbon dioxide sequestration, with the power island, where an oxy-combustion occurs. The experimental facility will be realized at the ENEA Research Centre of Casaccia at about thirty kilometres from the centre of Rome. It consists of a very flexible plant, in which more components can be tested separately or connected together. The plant is provided with an atmospheric fixed bed gasifier coal and a carbonator/calcinator reactor; moreover a pressurized hydrogasifier reactor and a 100 kWe microturbine test bench are present. Other auxiliary components are a gas mixing system, for hydrogen-based syngas production, and a 200 kW steam generator. 5 refs., 5 figs., 1 tab.

  17. Experimental Investigation of CFRP Confined Columns Damaged by Alkali Aggregate Reaction

    Siti Radziah Abdullah


    Full Text Available Fiber reinforced polymer is the most effective repair material in use to enhance the strength and ductility of deteriorated reinforced concrete columns. Often, fiber reinforced polymer (FRP provides passive confinement to columns until the dilation and cracking of concrete occurs. In the case of concrete suspected of Alkali Aggregate Reaction (AAR where concrete undergoes expansion, FRP wrap provides active confinement to the expanded concrete. In this study, the performance of carbon fiber reinforced polymer (CFRP wrapped columns damaged by AAR is evaluated based on the number of FRP layers and the time of the polymer application which provides two types of confinement: active or passive. The columns were tested under axial compression to evaluate the residual strength of the columns in comparison with unwrapped columns. The results reveal that the strength of the wrapped columns is enhanced with an increase in the number of CFRP layers. The strength of the columns under passive confinement is higher than the columns under active confinement. Under active confinement, early CFRP wrapping leads to improvement in the strength of the columns.

  18. Experimental analysis of reinforced concrete columns strengthened with Self-Compacting concrete

    M. Y. M. Omar

    Full Text Available This paper presents the results of reinforced concrete columns strengthened by addition of a self-compacting concrete overlay at the compressed and at the tensioned face of the member, with and without addition of longitudinal steel bars. Eight columns were submit- ted to loading with an initial eccentricity of 60 mm . These columns had 120 mm x 250 mm of rectangular cross section, 2000 mm in length and four longitudinal reinforcement steel bars with 10 mm in diameter. Reference columns P1 and P2 were tested to failure without any type of rehabilitation. Columns P3 to P8 were loaded to a predefined load (close to the initial yield point of tension reinforce- ment, then unloaded and strengthened for a subsequent test until failure. Results showed that the method of rehabilitation used was effective, increasing the loading capacity of the strengthened pieces by 2 to 5 times the ultimate load of the reference column.

  19. Methods for determining the CO2 sorption capacity of coal: Experimental and theoretical high pressure isotherms

    Weishauptová, Zuzana; Přibyl, Oldřich


    One way to reduce CO2 emissions discharged into the atmosphere is by trapping it and storing it in suitable repositories, including coal-bearing strata. The history of coal mining in the Czech Republic is very rich but most of the mines have been closed down in recent years. However, the unmined coal seams are interesting for the purposes of CO2 storage, especially due the opportunities they offer for recovering coal-bed methane. Mine structures of this kind can be found in large parts of the Upper Silesian Basin, where the total storage capacity has been estimated at about 380 Mt CO2. This is an interesting storage potential. In order to identify a suitable high-capacity locality for CO2 storage within a coal seam, it is necessary to study not only the geological conditions within the seam, but also the textural properties of the coal, which control the mechanism and the extent of the storage. The major storage mechanism is by sorption processes that take place in the coal porous system (adsorption in micropores and on the surface of meso/macropores, and absorption in the macromolecular structure). The CO2 sorption capacity is generally indirectly determined in a laboratory by measuring the amount of carbon dioxide captured in a coal sample at a pressure and temperature corresponding to the in situ conditions, using high pressure sorption techniques. The low pressure sorption technique can be used, by setting the partial volumes of CO2 according to its binding and storage mode. The sorption capacity is determined by extrapolation to the saturation pressure as the sum of the individual partially sorbed volumes. The aim of the study was to determine the partial volumes of CO2 bound by different mechanisms in the individual parts of the porous system of the coal, and to compare the sum with the results obtained by the high pressure isotherm. The study was carried out with 3 samples from a borehole survey in the Czech part of the Upper Silesian Basin. A high pressure

  20. Theoretical and experimental studies of fixed-bed coal gasification reactors. Final report

    Joseph, B.; Bhattacharya, A.; Salam, L.; Dudukovic, M.P.


    A laboratory fixed-bed gasification reactor was designed and built with the objective of collecting operational data for model validation and parameter estimation. The reactor consists of a 4 inch stainless steel tube filled with coal or char. Air and steam is fed at one end of the reactor and the dynamic progress of gasification in the coal or char bed is observed through thermocouples mounted at various radial and axial locations. Product gas compositions are also monitored as a function of time. Results of gasification runs using Wyoming coal are included in this report. In parallel with the experimental study, a two-dimensional model of moving bed gasifiers was developed, coded into a computer program and tested. This model was used to study the laboratory gasifier by setting the coal feed rate equal to zero. The model is based on prior work on steady state and dynamic modeling done at Washington University and published elsewhere in the literature. Comparisons are made between model predictions and experimental results. These are also included in this report. 23 references, 18 figures, 6 tables.

  1. Experimental investigation of the effect of liquid viscosity on slug flow in small diameter bubble column

    Azzopardi Barry John


    Full Text Available The effect of liquid viscosity on slug flow in a 50 mm diameter bubble column was investigated experimentally using air-silicone oil as operating fluid with silicone oil of viscosities 5, 100, 1000 and 5000 mPa.s. Data was collected using Electrical Capacitance Tomography (ECT, a non-intrusive advanced instrumentation measuring technique and the high Speed Video Camera, through which the slug parameters such as length of Taylor bubbles and liquid slug, void fraction in Taylor bubbles and liquid slug, slug frequency, film thickness and pressure gradient in the slug, were measured and analyzed. The analysis was done using the void fraction time series, probability density function and power spectral density plots. Superficial gas velocities of 0.02≤Ugs≤0.361 m/s were used in the experiment. It was also observed that as viscosity increases, slug frequency, structure velocity, length of liquid slug, void fraction in liquid slug and void fraction in Taylor bubbles decreases; while the length of Taylor bubble, film thickness and pressure gradient in the slug increases.

  2. Experimental study on the rheological behaviour of coal ash slurries

    Assefa K.M.


    Full Text Available Extensive experimental investigations were carried out to evaluate the rheological behaviour of fly ash (FA slurry without and with the addition of bottom ash (BA and BA slurry without and with the addition of FA. The FA slurries exhibited Bingham behaviour at solid mass concentrations ranging from 60–65% and mixing proportions from 10– 40%. A substantial reduction in yield stress was observed except for mixing proportion of 40% on which the yield stress and viscosity were increased drastically for all solid concentrations. Hence, it can be concluded that the yield stress and viscosity of FA slurry were very much influenced by adding BA up to the mixing proportion of 30%. The rheological behaviour of BA slurries with and without the addition of FA in proportions of 10–50% was investigated and exhibited Newtonian behaviours for solid mass concentrations ranging from 30–50% without and with the addition of FA. The viscosity increases with increasing the solid concentrations and proportion of FA. Based on these experimental data, a correlation was developed to predict the relative viscosity of BA slurries as a function of solid volume fraction and FA mass proportion of 0–50% and the RMSE and R2 values showed good agreement between the experimental and the predicted data.

  3. Failure Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    Moslemian, Ramin; Berggreen, Christian; Carlsson, Leif A.


    Failure of compression loaded sandwich columns with an implanted through-width face/core debond is examined. Compression tests were conducted on sandwich columns containing implemented face/core debonds. The strains and out-of-plane displacements of the debonded region were monitored using the di...

  4. Failure Investigation of Debonded Sandwich Columns: An Experimental and Numerical Study

    Moslemian, Ramin; Berggreen, Christian; Carlsson, Leif A.


    Failure of compression loaded sandwich columns with an implanted through-width face/core debond is examined. Compression tests were conducted on sandwich columns containing implemented face/core debonds. The strains and out-of-plane displacements of the debonded region were monitored using the di...

  5. CO2 sequestration in deep coal seams: experimental characterization of the fundamental underlying mechanisms

    Pini, R.; Mazzotti, M.


    The process of injecting and storing carbon dioxide (CO2) into suitable deep geological formations, such as saline aquifers, (depleted) oil or gas reservoirs, and unmineable coal seams, is referred to as CO2 sequestration. In little more than a decade, this technology has emerged as one of the most important options for reducing CO2 emissions. Among the different options, unmineable coal seams are not as broadly distributed as saline aquifers or oil/gas reservoirs, but their peculiarity resides in the proven capacity of retaining significant amount of gas (mainly methane, CH4) for a very long time. Additionally, the injection of CO2 into the coal reservoir would enhance the recovery of this natural gas, a source of energy that will most likely play a key role in the power sector over the next 20 years from now. This process is called Enhanced Coal Bed Methane (ECBM) recovery and, as for enhanced oil recovery, it allows in principle offsetting the costs associated to the storage operation. A study was undertaken aimed at the experimental characterization of the fundamental mechanisms that take place during the process of injection and storage in coal reservoirs, namely adsorption and swelling (Pini et al 2010), and of their effects on the coal's permeability (Pini et al. 2009), the property that plays a dominant role in controlling fluid transport in a porous rock. An apparatus has been built that allows measuring the permeability of rock cores under typical reservoir conditions (high pressure and temperature) by the so-called transient step method. For this study, a coal core from the Sulcis coal mine in Sardinia (Italy) has been used. In the experiments, an inert gas (helium) was used to investigate the effects of the effective pressure on the permeability of the coal sample, whereas two adsorbing gases (CO2 and N2) to quantify those of adsorption and swelling. The experiments have been interpreted by a one-dimensional model that describes the fluid transport

  6. An Experimental Study on Solidifying Municipal Sewage Sludge through Skeleton Building Using Cement and Coal Gangue

    Jiankang Yang


    Full Text Available The municipal sewage sludge typically has very high water content and low shear strength. Conventional methods of lime and cement solidification of municipal sewage sludge often suffer high cost, significant drying shrinkage, frequent cracking, high hydraulic conductivity, and low strength. To overcome these shortcomings, in this paper a skeleton-building method was used to solidify municipal sewage sludge in which coal gangue, cement and clay, and fiber were used as skeleton materials, cementation materials, and filling materials, respectively. Comprehensive laboratory tests including cracking, nitrogen adsorption, triaxial shearing, and permeability tests were performed to determine cracking, pore structure, shear strength, and hydraulic conductivity of municipal sewage sludge solidified with different proportions of coal gangue, cement, fiber, and clay. Based upon the experimental results, the mechanisms of the skeleton building using cement and coal gangue were discussed and factors controlling the mechanical and hydraulic behavior of the solidified soils were analyzed at both microscopic and macroscopic levels. Based upon the test results and analyses, recommendations were made for solidifying municipal sewage sludge through skeleton building using cement and coal gangue. The solidified soils have high soil strength, high resistance to cracking, and low hydraulic conductivity which are sufficient for being used as landfill liner.

  7. Multi-Column Experimental Test Bed Using CaSDB MOF for Xe/Kr Separation

    Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Processing of spent nuclear fuel produces off-gas from which several volatile radioactive components must be separated for further treatment or storage. As part of the Off-gas Sigma Team, parallel research at INL and PNNL has produced several promising sorbents for the selective capture of xenon and krypton from these off-gas streams. In order to design full-scale treatment systems, sorbents that are promising on a laboratory scale must be proven under process conditions to be considered for pilot and then full-scale use. To that end, a bench-scale multi-column system with capability to test multiple sorbents was designed and constructed at INL. This report details bench-scale testing of CaSDB MOF, produced at PNNL, and compares the results to those reported last year using INL engineered sorbents. Two multi-column tests were performed with the CaSDB MOF installed in the first column, followed with HZ-PAN installed in the second column. The CaSDB MOF column was placed in a Stirling cryocooler while the cryostat was employed for the HZ-PAN column. Test temperatures of 253 K and 191 K were selected for the first column while the second column was held at 191 K for both tests. Calibrated volume sample bombs were utilized for gas stream analyses. At the conclusion of each test, samples were collected from each column and analyzed for gas composition. While CaSDB MOF does appear to have good capacity for Xe, the short time to initial breakthrough would make design of a continuous adsorption/desorption cycle difficult, requiring either very large columns or a large number of smaller columns. Because of the tenacity with which Xe and Kr adhere to the material once adsorbed, this CaSDB MOF may be more suitable for use as a long-term storage solution. Further testing is recommended to determine if CaSDB MOF is suitable for this purpose.

  8. Water table fluctuations and soil biogeochemistry: An experimental approach using an automated soil column system

    Rezanezhad, F.; Couture, R.-M.; Kovac, R.; O'Connell, D.; Van Cappellen, P.


    Water table fluctuations significantly affect the biological and geochemical functioning of soils. Here, we introduce an automated soil column system in which the water table regime is imposed using a computer-controlled, multi-channel pump connected to a hydrostatic equilibrium reservoir and a water storage reservoir. The potential of this new system is illustrated by comparing results from two columns filled with 45 cm of the same homogenized riparian soil. In one soil column the water table remained constant at -20 cm below the soil surface, while in the other the water table oscillated between the soil surface and the bottom of the column, at a rate of 4.8 cm d-1. The experiment ran for 75 days at room temperature (25 ± 2 °C). Micro-sensors installed at -10 and -30 cm below the soil surface in the stable water table column recorded constant redox potentials on the order of 600 and -200 mV, respectively. In the fluctuating water table column, redox potentials at the same depths oscillated between oxidizing (∼700 mV) and reducing (∼-100 mV) conditions. Pore waters collected periodically and solid-phase analyses on core material obtained at the end of the experiment highlighted striking geochemical differences between the two columns, especially in the time series and depth distributions of Fe, Mn, K, P and S. Soil CO2 emissions derived from headspace gas analysis exhibited periodic variations in the fluctuating water table column, with peak values during water table drawdown. Transient redox conditions caused by the water table fluctuations enhanced microbial oxidation of soil organic matter, resulting in a pronounced depletion of particulate organic carbon in the midsection of the fluctuating water table column. Denaturing Gradient Gel Electrophoresis (DGGE) revealed the onset of differentiation of the bacterial communities in the upper (oxidizing) and lower (reducing) soil sections, although no systematic differences in microbial community structure

  9. Experimental Study of Imbibition Characteristics of Silica Sol in Coal-Measure Mudstone Matrix

    Dongjiang Pan


    Full Text Available Coal-measure mudstone is a typical dual-porosity media, and grouting in a matrix system is dominantly controlled by the imbibition effect for silica sol. This paper studies the imbibition effect using mudstone in the Huaibei mining area and silica sol as grouting material as an example. Groutability, driving force, and diffusion difficulty affecting the imbibition effect were tested by a mercury porosimeter, nanoparticle size analyzer, optical contact-angle measuring device, surface tension meter, and rotary viscosity meter. After finely grinding a mudstone sample, a pressureless imbibition process was conducted through nuclear magnetic resonance equipment for 216 h to study colloid spontaneous migration and phase characteristics. Results show that silica sol absorption rate follows a power function and that the spectrograms of T2 are distributed in a triple peak pattern, with a tendency to move to the right of vertex time. The paper lays a theoretical and experimental foundation for field grouting in the coal mine.

  10. A Planning Experimental Investigation on Tobacco Leaves Dryer Using Paddy Husk and Coal

    Huy Bich Nguyen


    Full Text Available In Viet Nam, the drying technology and techniques for tobacco leaves is one of the most difficulties and plays as key point to get high economic efficiency in tobacco production. To drying for tobacco leaves of 3,500 hectare, for example in Gia Lai province, there needs about 3000 dryers and there is more than 100,000 cubic meter of wood have been burned for drying which equivalent to more than 300 hectare of forest is deforested annually. A designing and manufacturing study for new tobacco dryer to replace the wood fuel by paddy-husk or coal-wood has been implemented. The results indicate that the new dryer using rice-husk or coal can be replaced for the actual drying system used fire wood with the high quality of tobacco leaves and high efficiency. The planning experimental investigation has found the function of the rate of energy consumption and the quality of drying products successful

  11. Semi-industrial experimental study on bauxite separation using a cell-column integration process

    Zhang, Ning-ning; Zhou, Chang-chun; Cong, Long-fei; Cao, Wen-long; Zhou, You


    The cyclonic-static micro-bubble flotation column (FCSMC) is a highly efficient mineral processing equipment. In this study, a cell-column (FCSMC) integration process was investigated for the separation of bauxite and its feasibility was analyzed on a theoretical basis. The properties of low-grade bauxite ore from Henan Province, China were analyzed. Parameters such as reagent dosage, scraping bubble time, and pressure of the circulating pump during the sorting process were investigated and optimized to improve the flotation efficiency. On the basis of these parameters, continuous separation experiments were conducted. Bauxite concentrate with an aluminum-to-silicon (A/S) mass ratio of 6.37 and a 77.63wt% recovery rate were achieved via a flow sheet consisting of "fast flotation using a flotation cell, one roughing flotation and one cleaning flotation using flotation columns". Compared with the full-flotation-cells process, the cell-column integration process resulted in an increase of the A/S ratio by 0.41 and the recovery rate by 17.58wt%. Cell-column integration separation technology represents a new approach for the separation of middle-to-low-grade bauxite ore.

  12. Experimental evaluation of the prevention methods for the interface between masonry infill walls and concrete columns

    A. P. Tramontin

    Full Text Available Cracks that form at the interfaces between masonry structures are common uncontrolled occurrences in buildings. Numerous methods have been proposed by the construction industry to address this problem. Cracks continuously form in the joints between concrete columns and masonry infill walls. In this study, the most common methods for preventing these types of cracks were evaluated in laboratory experiments. Column masonry models were constructed using different types of joints between concrete columns and masonry infill walls, such as steel bars and steel mesh. The efficiency of each type of joint method was evaluated by performing direct tensile tests (pullout tests on the models and monitoring the evolution of the crack opening in the joint between the column and wall, as a function of load applied to the model. The results from this study indicate that the model composed of "electrowelded wire mesh without steel angles" is the best model for controlling cracking in the joints between concrete columns and masonry infill walls.

  13. 煤泥的浮选试验研究%Flotation experimental study of the coal slime

    缪长勇; 郭喜民


    That article illustrates the advantages, and takes the coal slime from some company as an example, a research is conducted that makes coMParison between flotation column and flotation machine. Eventually the results show that the flotation column is more predominant in reducing the ash in clean coal and improving the efficiency of sizing coMParing to the flotation machines.%该文阐述了浮选柱的优点,并以某选煤厂煤泥为例,分别进行了浮选柱与浮选机的对比试验研究。结果表明:浮选柱在降低精煤灰分、提高分选效率方面,浮选柱比浮选机具有显著的优越性。

  14. Modelling and experimental verification on concrete-filled steel tubular columns with L or T section

    LU Xilin; LI Xueping; WANG Dan


    Concrete-filled steel tubular columns with L or T sections were analyzed in this paper. According to the confin- ing mechanism, the stress-strain constitutive model was put forward, and calculated results were compared with experi- mental records. After that, the hysteretic rules for the in-filled concrete were constructed, aiming at the analysis on the seis- mic behavior of composite members. The simulation analysis was performed by programming it in Fortran. The models in this paper can be applied in the program of time history analysis on tall buildings with concrete-filled steel tubular columns with L or T sections.

  15. Experimental Investigation of Thermal Characteristics of Kiwira Coal Waste with Rice Husk Blends for Gasification

    Deodatus Kazawadi


    Full Text Available Eminent depletion of fossil fuels and environmental pollution are the key forces driving the implementation cofiring of fossil fuels and biomass. Cogasification as a technology is known to have advantages of low cost, high energy recovery, and environmental friendliness. The performance/efficiency of this energy recovery process substantially depends on thermal properties of the fuel. This paper presents experimental study of thermal behavior of Kiwira coal waste/rice husks blends. Compositions of 0, 20, 40, 60, 80, and 100% weight percentage rice husk were studied using thermogravimetric analyzer at the heating rate of 10 K/min to 1273 K. Specifically, degradation rate, conversion rate, and kinetic parameters have been studied. Thermal stability of coal waste was found to be higher than that of rice husks. In addition, thermal stability of coal waste/rice husk blend was found to decrease with an increase of rice husks. In contrast, both the degradation and devolatilization rates increased with the amount of rice husk. On the other hand, the activation energy dramatically reduced from 131 kJ/mol at 0% rice husks to 75 kJ/mol at 100% rice husks. The reduction of activation energy is advantageous as it can be used to design efficient performance and cost effective cogasification process.

  16. Semi-industrial experimental study on bauxite separation using a cellcolumn integration process

    Ning-ning Zhang; Chang-chun Zhou; Long-fei Cong; Wen-long Cao; You Zhou


    The cyclonic-static micro-bubble flotation column (FCSMC) is a highly efficient mineral processing equipment. In this study, a cell-column (FCSMC) integration process was investigated for the separation of bauxite and its feasibility was analyzed on a theoretical basis. The properties of low-grade bauxite ore from Henan Province, China were analyzed. Parameters such as reagent dosage, scraping bubble time, and pressure of the circulating pump during the sorting process were investigated and optimized to improve the flotation efficiency. On the basis of these parameters, continuous separation experiments were conducted. Bauxite concentrate with an aluminum-to-silicon (A/S) mass ratio of 6.37 and a 77.63wt% recovery rate were achieved via a flow sheet consisting of “fast flotation using a flotation cell, one roughing flotation and one cleaning flotation using flotation columns”. Compared with the full-flotation-cells process, the cell-column integration process resulted in an increase of the A/S ratio by 0.41 and the recovery rate by 17.58wt%. Cell-column integration separation technology represents a new approach for the separation of middle-to-low-grade bauxite ore.

  17. Experimental Study on Mechanical Property of Steel Reinforced Concrete L-Shaped Short Columns

    Li, Zhe; Qin, Hao; Dang, Hui; Li, Hui; Zhang, Jian-Shan

    The horizontal press performance of column is deteriorated because of its special-shaped section. Moreover, because the antiseismic performance of column is worse, special-shaped column is only used in regions where seismic intensity is lower. So the main problem is to enhance the ductility and shear capacity. This test study on mechanical performance has been carried out through 14 SRCLSSC and 2 RCLSSC. The study focuses on the impacts of test axial load ratio (nt), hooped reinforcement ratio (ρv), shear span ratio (λ) and steel ratio (ρss) on the shear strength and the antiseismic performance of SRCLSSC. It can be concluded that the shear strength of SRCLSSC is increasing with the increasing of nt and ρss, but the degree of increasing is small when nt is a certainty value, and that the shear strength of SRCLSSC is decreasing with increasing of λ The shear resistance formula of L-shaped column is derived through tests, the calculated results are in correspondence with those of the tests. It also can be concluded that the hysteretic loops of the SRCLSSC are full and the hysteretic behaviors are improved; the displacement ductility is increasing with increasing of ρv and ρss, but decreasing with the increasing of nt; the degree of variety in high axial load ratio is larger than that in low axial load ratio. If steel bars are added, the shear strength and displacement ductility of SRCLSSC are increased in a large degree.

  18. Experimental study on the seismic behavior of high strength concrete filled double-tube columns

    Qian, Jiaru; Li, Ningbo; Ji, Xiaodong; Zhao, Zuozhou


    To study the seismic behavior of high strength concrete filled double-tube (CFDT) columns, each consisting of an external square steel tube and an internal circular steel tube, quasi-static tests on eight CFDT column specimens were conducted. The test variables included the width-to-thickness ratio ( β 1) and the area ratio ( β 2) of the square steel tube, the wall thickness of the circular steel tube, and the axial force (or the axial force ratio) applied to the CFDT columns. The test results indicate that for CFDT columns with a square steel tube with β 1 of 50.1 and 24.5, local buckling of the specimen was found at a drift ratio of 1/150 and 1/50, respectively. The lateral force-displacement hysteretic loops of all specimens were plump and stable. Reducing the width-to-thickness ratio of the square steel tube, increasing its area ratio, or increasing the wall thickness of the internal circular steel tube, led to an increased flexural strength and deformation capacity of the specimens. Increasing the design value of the axial force ratio from 0.8 to 1.0 may increase the flexural strength of the specimens, while it may also decrease the ultimate deformation capacity of the specimen with β 1 of 50.1.

  19. Modeling of Crystalline Silicotitanate Ion Exchange Columns Using Experimental Data from SRS Simulated Waste

    Walker, D.D.


    Non-elutable ion exchange using crystalline silicotitanate is being considered for removing cesium from Savannah River Site radioactive waste. The construction cost of this process depends strongly on the size of the ion exchange column required to meet product specifications.

  20. Experimental research of sewage sludge with coal and biomass co-combustion, in pellet form.

    Kijo-Kleczkowska, Agnieszka; Środa, Katarzyna; Kosowska-Golachowska, Monika; Musiał, Tomasz; Wolski, Krzysztof


    Increased sewage sludge production and disposal, as well as the properties of sewage sludge, are currently affecting the environment, which has resulted in legislation changes in Poland. Based on the Economy Minister Regulation of 16 July 2015 (Regulation of the Economy Minister, 2015) regarding the criteria and procedures for releasing wastes for landfilling, the thermal disposal of sewage sludge is important due to its gross calorific value, which is greater than 6MJ/kg, and the problems that result from its use and application. Consequently, increasingly restrictive legislation that began on 1 January 2016 was introduced for sewage sludge storage in Poland. Sewage sludge thermal utilisation is an attractive option because it minimizes odours, significantly reduces the volume of starting material and thermally destroys the organic and toxic components of the off pads. Additionally, it is possible that the ash produced could be used in different ways. Currently, as many as 11 plants use sewage sludge as fuel in Poland; thus, this technology must be further developed in Poland while considering the benefits of co-combustion with other fuels. This paper presents the results of experimental studies of the mechanisms and kinetics of sewage sludge, coal and biomass combustion and their co-combustion in spherical-pellet form. Compared with biomass, a higher temperature is required to ignite sewage sludge by flame. The properties of biomass and sewage sludge result in the intensification of the combustion process (by fast ignition of volatile matter). In contrast to coal, a combustion of sewage sludge is determined not only burning the char, but also the combustion of volatiles. The addition of sewage sludge to hard coal and lignite shortens combustion times compared with coal, and the addition of sewage sludge to willow Salix viminalis produces an increase in combustion time compared with willow alone. Copyright © 2016 Elsevier Ltd. All rights reserved.


    Isaac K. Gamwo; Dimitri Gidaspow


    Considerable progress has been achieved in understanding three-phase reactors from the point of view of kinetic theory. In a paper in press for publication in Chemical Engineering Science (Wu and Gidaspow, 1999) we have obtained a complete numerical solution of bubble column reactors. In view of the complexity of the simulation a better understanding of the processes using simplified analytical solutions is required. Such analytical solutions are presented in the attached paper, Large Scale Oscillations or Gravity Waves in Risers and Bubbling Beds. This paper presents analytical solutions for bubbling frequencies and standing wave flow patterns. The flow patterns in operating slurry bubble column reactors are not optimum. They involve upflow in the center and downflow at the walls. It may be possible to control flow patterns by proper redistribution of heat exchangers in slurry bubble column reactors. We also believe that the catalyst size in operating slurry bubble column reactors is not optimum. To obtain an optimum size we are following up on the observation of George Cody of Exxon who reported a maximum granular temperature (random particle kinetic energy) for a particle size of 90 microns. The attached paper, Turbulence of Particles in a CFB and Slurry Bubble Columns Using Kinetic Theory, supports George Cody's observations. However, our explanation for the existence of the maximum in granular temperature differs from that proposed by George Cody. Further computer simulations and experiments involving measurements of granular temperature are needed to obtain a sound theoretical explanation for the possible existence of an optimum catalyst size.

  2. Coal Recycling from Tailings using Flotation with 2-Level Experimental Design Techniques

    Sajjad Jannesar Malakooti


    Full Text Available In this study, the possibility of producing coal with less than 11% ash from tailings of flotation process was investigated. The effect of six flotation parameters: collector type, collector consumption, frother type, frother consumption, pulp density and mixing rate were studied on a sample from a tailing dam. A software based experimental design approach (DX7 was applied to determine and model effective parameters as well as flotation optimization through fractional factorial. It was shown that collector type and flotation machine mixing rate were the most effective parameters on ash content of concentrate. The results indicated that the production of a desired ash content concentrate, i.e.

  3. Experimental Investigation of Flow Resistance in a Coal Mine Ventilation Air Methane Preheated Catalytic Oxidation Reactor

    Bin Zheng


    Full Text Available This paper reports the results of experimental investigation of flow resistance in a coal mine ventilation air methane preheated catalytic oxidation reactor. The experimental system was installed at the Energy Research Institute of Shandong University of Technology. The system has been used to investigate the effects of flow rate (200 Nm3/h to 1000 Nm3/h and catalytic oxidation bed average temperature (20°C to 560°C within the preheated catalytic oxidation reactor. The pressure drop and resistance proportion of catalytic oxidation bed, the heat exchanger preheating section, and the heat exchanger flue gas section were measured. In addition, based on a large number of experimental data, the empirical equations of flow resistance are obtained by the least square method. It can also be used in deriving much needed data for preheated catalytic oxidation designs when employed in industry.

  4. Column chromatography with almecega resin: a project for experimental organic chemistry; Cromatografando em coluna com resina de almecega: um projeto para quimica organica experimental

    Vieira Junior, Gerardo Magela; Carvalho, Adonias Almeida; Gonzaga, Wellington de Abreu; Chaves, Mariana H. [Universidade Federal do Piaui, Teresina, PI (Brazil). Dept. de Quimica]. E-mail:


    The use of natural products to demonstrate the silica gel column chromatography technique is proposed in the present article. It describes the separation of the triterpenes {alpha}- and {beta}-amirin from the diol breine and maniladiol, obtained from almecega resin (Protium heptaphyllum March.). The experiment uses an accessible material, was accomplished in 4 h, and can be applied with success an the experimental course of organic chemistry for undergraduate students. (author)

  5. Experimental and Theoretical Analysis of Hollow Steel Columns Strengthening by CFRP

    Keykha A.H.


    Full Text Available The need for strengthening and retrofitting is well known and extensive research is progressing in this field. The reasons for strengthening and retrofitting are numerous: increased loads, changes in use, deterioration, and so on. In recent years, the use of carbon fiber reinforced polymer (CFRP for strengthening has shown to be a competitive method, both regarding structural performance, and economical aspects. Extensive research has been carried out in this field. However, most of the research has been undertaken on concrete structures and for confinement, flexural, and shear strengthening. Limited research has been carried out on steel structures strengthened with CFRP. This paper presents axially loaded steel columns strengthened for increased load. The topic is studied theoretically and through laboratory tests. The theory covers analytical methods. Carbon fiber reinforced polymers has been used to strengthen the columns. The tests have been undertaken on full scale specimens, non-strengthened for reference, partially strengthened and fully strengthened

  6. Experimental Ion Exchange Column With SuperLig 639 And Simulant Formulation

    Morse, Megan; Nash, C.


    SuperLig®639 ion exchange resin was tested as a retrieval mechanism for pertechnetate, through decontamination of a perrhenate spiked 5M Simple Average Na{sup +} Mass Based Simulant. Testing included batch contacts and a three-column ion exchange campaign. A decontamination of perrhenate exceeding 99% from the liquid feed was demonstrated. Analysis of the first formulation of a SBS/WESP simulant found unexpectedly low concentrations of soluble aluminum. Follow-on work will complete the formulation.

  7. Experimental design and statistical analysis in Rotating Disc Contactor (RDC) column

    Ismail, Wan Nurul Aiffah; Zakaria, Siti Aisyah; Noor, Nor Fashihah Mohd; Ariffin, Wan Nor Munirah


    The purpose of this paper is to examine the performance of the liquid-liquid extraction in Rotating Disc Contactor (RDC) Column that being used in industries. In this study, the performance of small diameter column RDC using the chemical system involving cumene/isobutryric asid/water are analyzed by the method of design of the experiments (DOE) and also Multiple Linear Regression (MLR). The DOE method are used to estimated the effect of four independent. Otherwise, by using Multiple Linear Regression (MLR) is to justify the relationship between the input variables and output variables and also to determine which variable are more influence for both output variable. The input variables for both method include rotor speed (Nr); ratio of flow (Fd); concentration of continuous inlet (Ccin); concentration of dispersed inlet (Cdin); interaction between Nr with Fd; interaction between Nr with Ccin; interaction Nr with Cdin. Meanwhile the output variables are concentration of continuous outlet (Ccout) and concentration of dispersed outlet (Cdout) on RDC column performance. By using this two method, we have two linear model represent two output of Ccout and Cdout for MLR. Lastly, the researcher want to determine which input variable that give more influence to output variable by using this two method. Based on the result, we obtained that rotor speed (Nr) more influence to dependent variable, Ccout and concentration of continuous inlet (Ccin) more influence to dependent variable, Cdout according the two method that was used.

  8. Experimental study of the stability and flow characteristics of floating liquid columns confined between rotating disks

    Fowle, A. A.; Soto, L.; Strong, P. F.; Wang, C. A.


    A low Bond number simulation technique was used to establish the stability limits of cylindrical and conical floating liquid columns under conditions of isorotation, equal counter rotation, rotation of one end only, and parallel axis offset. The conditions for resonance in cylindrical liquid columns perturbed by axial, sinusoidal vibration of one end face are also reported. All tests were carried out under isothermal conditions with water and silicone fluids of various viscosities. A technique for the quantitative measurement of stream velocity within a floating, isothermal, liquid column confined between rotatable disks was developed. In the measurement, small, light scattering particles were used as streamline markers in common arrangement, but the capability of the measurement was extended by use of stereopair photography system to provide quantitative data. Results of velocity measurements made under a few selected conditions, which established the precision and accuracy of the technique, are given. The general qualitative features of the isothermal flow patterns under various conditions of end face rotation resulting from both still photography and motion pictures are presented.

  9. Chemical analysis of soil and leachate from experimental wetland mesocosms lined with coal combustion products

    Ahn, C.; Mitsch, W.J. [Ohio State University, Columbus, OH (USA). Environmental Science Graduate Program and School of Natural Resources


    Small-scale (1 m{sup 2}) wetland mesocosm experiments were conducted over two consecutive growing seasons to investigate the effects on soil and leachate chemistry of using a recycled coal combustion product as a liner. The coal combustion product used as a liner consisted of flue gas desulfurization (FGD) by-products and fly ash. This paper provides the chemical characteristics of mesocosm soil and leachate after 2 yr of experimentation. Arsenic, Ca and pH were higher in FGD-lined mesocosm surface soil relative to unlined mesocosms. Aluminium was higher in the soils of unlined mesocosms relative to FGD-lined mesocosms. No significant difference of potentially phytotoxic B was observed between lined and unlined mesocosms in the soil. Higher pH, conductivity and concentrations of Al, B, Ca, K and S (SO{sub 4}-S) were observed in leachate from lined mesocosms compared with unlined controls while Fe, Mg and Mn were higher in leachate from unlined mesocosms. Concentrations of most elements analyzed in the leachate were below national primary and secondary drinking water standards after 2 yr of experimentation. Initially high pH and soluble salt concentrations measured in the leachate from the lined mesocosms may indicate the reason for early effects noted on the development of wetland vegetation in the mesocosms. 32 refs., 2 figs., 3 tabs.

  10. Assessment of in-furnace dry sorbent injection experimental results burning low sulphur content coals

    Collado, F.J. [Univ. de Zaragoza (Spain)


    In an effort to adjust the SO{sub 2} emissions of coal power stations to the current air pollutant standards, established by the EC, flue gas desulfurization tests with in-furnace dry sorbent injection technology in the Spanish coal power station ``Litoral`` (tangentially-fired) were performed. The measured retentions were lower than predicted through a one-dimensional model. Then, it was thought that a CFD 3D simulation of the injection would help to understand the complex relationships of the process. The simulation was divided in two stages: in the first one, the turbulent velocity and the temperature field were solved. In the second one, representative sorbent particles were injected in the turbulent field previously solved, the focus of this work being the global sulphur capture modeling and its validation through the experimental measurements obtained. After a revision of the models proposed in the specialized literature, a global sulfation model is chosen, being compared with the experimental data obtained in the power station. Because of the main results of this work, the authors can highlight the testing of the laboratory-scale correlations against full-scale results, and can mitigate the difficulty of estimating the actual temperature profile by experimenting with the particle and its residence time without the aid of a CFD code.

  11. 旋流微泡浮选柱在涡北选煤厂的应用%Application of cyclon micro bubble flotation column in Wobei coal preparation plant

    冯立品; 周孟颖; 徐晓琦


    According to analysis of the size composition of coal slime, find that coal gangue pelitization, high content of high-ash fine mud are bad for Rotating. Single facter flotation tests of flotation machine, two factors and three levels orthogonal tests, substep releasing tests with the optimal mixture of flotation reagents have been taken. The results show that,while the mass concentration of coal slime pulp is 45 g/L and mixture flotation reagents is 1. 10 kg/t,clean coal ash could reaches 10. 97% productivity of clean coal is 72. 62% ,improved flotation index is up to 53. 43% and the flotation machine works best. The flotation column could separate all kinds of fine coal,fine coal ash could be adjusted in wide range in order to meet the requirements. The comprehensive contrast tests of flotation machine and flotation column are taken at last, disposing the same clean coal ash, the results show that flotation column could highly improve clean coal recovery and flotation index compared with the flotation machine.%分析了涡北选煤厂煤泥粒度组成,发现煤样矸石存在泥化现象,高灰细泥含量较高,对浮选不利.进行了浮选机的单因素浮选试验、两因素三水平正交试验以及最优药剂条件下的分步释放试验,同时进行了浮选柱的煤泥浮选试验.结果表明,当煤泥矿浆质量浓度为45 g/L,复合药剂为1.10 kg/t时,精煤灰分为10.97%,精煤产率为72.62%,浮选完善指标最高为53.43%,浮选机煤泥浮选效果最好;浮选柱可以分选出各种质量的精煤,精煤灰分可调性大,可以适应市场变化.最后进行了浮选机和浮选柱的综合对比试验,在精煤灰分相近的情况下,浮选柱不同程度地提高了精煤回收率和浮选完善指标,具有明显优势.

  12. Experimental Study on the Changing Rules of Coal Fire Indictor Gases of the Whole Combustion Phases in Confined Space

    Baiwei Lei

    Full Text Available ABSTRACT When the coal mine fire occurs, it is crucial to judge the fire combustion state by analyzing indicator gases concentration and changing trends of various gas ratios in order to formulate proper rescue measures. It's an effective methodology to estimate the changes of combustion state in coal mine fire accurately by the trends analysis of indicator gases and gas ratios independent of the external environment disturbs, such as air leakage and inner gases injection. However, there are few experimental researches about the changing rules of indicator gases and gas ratios at different combustion phases at present. Therefore, this paper has established a small-sized coal combustion experimental platform in confined space, on which the experimental studies on variation trends about indicator gases and gas ratios of the whole combustion phases are conducted. The experiment results have shown that the coal combustion trends could be accurately estimated by analyzing the relationship between indicator gases and gas ratios among different combustion phases. In the end of this paper, the conclusions are verified by a real coal mine fire disaster relief case, and the practical results are in agreement with the experimental analysis.


    Lambert, D.; Choi, A.


    This report summarizes the results of both experimental and modeling studies performed using Sludge Batch 10 (SB10) simulants and FBSR product from Tank 48 simulant testing in order to develop higher levels of coal-carbon that can be managed by DWPF. Once the Fluidized Bed Steam Reforming (FBSR) process starts up for treatment of Tank 48 legacy waste, the FBSR product stream will contribute higher levels of coal-carbon in the sludge batch for processing at DWPF. Coal-carbon is added into the FBSR process as a reductant and some of it will be present in the FBSR product as unreacted coal. The FBSR product will be slurried in water, transferred to Tank Farm and will be combined with sludge and washed to produce the sludge batch that DWPF will process. The FBSR product is high in both water soluble sodium carbonate and unreacted coal-carbon. Most of the sodium carbonate is removed during washing but all of the coal-carbon will remain and become part of the DWPF sludge batch. A paper study was performed earlier to assess the impact of FBSR coal-carbon on the DWPF Chemical Processing Cell (CPC) operation and melter off-gas flammability by combining it with SB10-SB13. The results of the paper study are documented in Ref. 7 and the key findings included that SB10 would be the most difficult batch to process with the FBSR coal present and up to 5,000 mg/kg of coal-carbon could be fed to the melter without exceeding the off-gas flammability safety basis limits. In the present study, a bench-scale demonstration of the DWPF CPC processing was performed using SB10 simulants spiked with varying amounts of coal, and the resulting seven CPC products were fed to the DWPF melter cold cap and off-gas dynamics models to determine the maximum coal that can be processed through the melter without exceeding the off-gas flammability safety basis limits. Based on the results of these experimental and modeling studies, the presence of coal-carbon in the sludge feed to DWPF is found to have

  14. Experimental Study on Elastic-Plastic Behavior of SRC Columns with High Strength Steel


    The demand to use high strength and high performance material because of large span and high rise of building in recent years. As to use of high-strength steel in composite steel and reinforced concrete structures, it remains to be clarified whether the ductile behavior can be ensured, especially when the high-strength steel is used in combination with High-strength concrete. This paper describes the test results on the elasto-plastic behavior of SRC column using high strength steel, and disc...

  15. Dynamic performance of angle-steel concrete columns under low cyclic loading-I: Experimental study

    Zheng, Wenzhong; Ji, Jing


    This paper describes low cyclic loading testing of nine angle-steel concrete column (ASCC) specimens. In the tests, the influence of the shear-span ratio, axial compression ratio and shear steel plate ratio on the hysteretic behavior, energy dissipation, strength degradation, stiffness degradation, skeleton curve and ductility of the ASCCs is studied. Based on the test results, some conclusions are presented. The P- Δ and sectional M — ϕ hysteretic models for the ASCCs are presented in a companion paper (Zheng and Ji, 2008).

  16. Dynamic performance of angle-steel concrete columns under low cyclic loading-I: Experimental study

    Zheng Wenzhong; Ji Jing


    This paper describes low cyclic loading testing of nine angle-steel concrete column (ASCC) specimens. In the tests, the influence of the shear-span ratio, axial compression ratio and shear steel plate ratio on the hysteretic behavior, energy dissipation, strength degradation, stiffness degradation, skeleton curve and ductility of the ASCCs is studied. Based on the test results, some conclusions are presented. The P-Δ and sectional M-(Φ) hysteretic models for the ASCCs are presented in a companion paper (Zheng and Ji, 2008).

  17. Experimental study on NOx emission and unburnt carbon of a radial biased swirl burner for coal combustion

    Shan Xue; Shi' en Hui; Qulan Zhou; Tongmo Xu [Xi' an Jiaotong University, Xi' an (China). State Key Laboratory of Multiphase Flow in Power Engineering


    Pilot tests were carried out on a 1 MW thermal pulverized coal fired testing furnace. Symmetrical combustion was implemented by use of two whirl burners with dual air adjustment. The burnout air device was installed in various places at the top of the main burner, which consists of a primary air pipe with a varying cross-section and an impact ring. In the primary air pipe, the air pulverized coal (PC) stream was separated into a whirling stream that was thick inside and thin outside, thus realizing the thin-thick distribution at the burner nozzle in the radial direction. From the comparative combustion tests of three coals with relatively great characteristic differences, Shaanbei Shenhua high rank bituminous coal (SH coal), Shanxi Hejin low rank bituminous coal (HJ coal), and Shanxi Changzhi meager coal (CZ coal), were obtained such test results as the primary air ratio, inner secondary air ratio, outer secondary air ratio, impact of the change of outer secondary air, change of the relative position for the layout of burnout air, change of the swirling intensity of the primary air and secondary air, etc., on the NOx emission, and unburnt carbon content in fly ash (CFA). At the same time, the relationship between the NOx emission and burnout ratio and affecting factors of the corresponding test items on the combustion stability and economic results were also acquired. The results may provide a vital guiding significance to engineering designs and practical applications. According to the experimental results, the influence of each individual parameter on NOx formation and unburned carbon in fly ash agrees well with the existing literature. In this study, the influences of various combinations of these parameters are also examined, thus providing some reference for the design of the radial biased swirl burner, the configuration of the furnace, and the distribution of the air. 23 refs., 14 figs., 2 tabs.

  18. Behavior of wet precast beam column connections under progressive collapse scenario: an experimental study

    Nimse, Rohit B.; Joshi, Digesh D.; Patel, Paresh V.


    Progressive collapse denotes a failure of a major portion of a structure that has been initiated by failure of a relatively small part of the structure such as failure of any vertical load carrying element (typically columns). Failure of large part of any structure will results into substantial loss of human lives and natural resources. Therefore, it is important to prevent progressive collapse which is also known as disproportionate collapse. Nowadays, there is an increasing trend toward construction of buildings using precast concrete. In precast concrete construction, all the components of structures are produced in controlled environment and they are being transported to the site. At site such individual components are connected appropriately. Connections are the most critical elements of any precast structure, because in past major collapse of precast structure took place because of connection failure. In this study, behavior of three different 1/3rd scaled wet precast beam column connections under progressive collapse scenario are studied and its performance is compared with monolithic connection. Precast connections are constructed by adopting different connection detailing at the junction by considering reinforced concrete corbel for two specimens and steel billet for one specimen. Performance of specimen is evaluated on the basis of ultimate load carrying capacity, maximum deflection and deflection measured along the span of the beam. From the results, it is observed that load carrying capacity and ductility of precast connections considered in this study are more than that of monolithic connections.

  19. Experimental study on seismic behavior of circular RC columns strengthened with pre-stressed FRP strips

    Zhou, Changdong; Lu, Xilin; Li, Hui; Tian, Teng


    Bonding fiber reinforced polymer (FRP) has been commonly used to improve the seismic behavior of circular reinforced concrete (RC) columns in engineering practice. However, FRP jackets have a significant stress hysteresis effect in this strengthening method, and pre-tensioning the FRP can overcome this problem. This paper presents test results of 25 circular RC columns strengthened with pre-stressed FRP strips under low cyclic loading. The pre-stressing of the FRP strips, types of FRP strips and longitudinal reinforcement, axial load ratio, pre-damage degree and surface treatments of the specimens are considered as the primary factors in the tests. According to the failure modes and hysteresis curves of the specimens, these factors are analyzed to investigate their effect on bearing capacity, ductility, hysteretic behavior, energy dissipation capacity and other important seismic behaviors. The results show that the initial lateral confined stress provided by pre-stressed FRP strips can effectively inhibit the emergence and development of diagonal shear cracks, and change the failure modes of specimens from brittle shear failure to bending or bending-shear failure with better ductility. As a result, the bearing capacity, ductility, energy dissipation capacity and deformation capacity of the strengthened specimens are all significantly improved.

  20. Experimental analysis of a combustion reactor under co-firing coal with biomass

    Pereira, Fabyo Luiz; Bazzo, Edson; Oliveira Junior, Amir Antonio Martins de [Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil). LabCET], e-mail:; Bzuneck, Marcelo [Tractebel Energia S.A., Complexo Termeletrico Jorge Lacerda, Capivari de Baixo, SC (Brazil)], e-mail:


    Mitigation of greenhouse gases emission is one of the most important issues in energy engineering. Biomass is a potential renewable source but with limited use in large scale energy production because of the relative smaller availability as compared to fossil fuels, mainly to coal. Besides, the costs concerning transportation must be well analysed to determine its economic viability. An alternative for the use of biomass as a primary source of energy is the co-firing, that is the possibility of using two or more types of fuels combined in the combustion process. Biomass can be co-fired with coal in a fraction between 10 to 25% in mass basis (or 4 to 10% in heat-input basis) without seriously impacting the heat release characteristics of most boilers. Another advantage of cofiring, besides the significant reductions in fossil CO{sub 2} emissions, is the reduced emissions of NO{sub x} and SO{sub x}. As a result, co-firing is becoming attractive for power companies worldwide. This paper presents results of some experimental analysis on co-firing coal with rice straw in a combustion reactor. The influence of biomass thermal share in ash composition is also discussed, showing that alkali and earth alkaline compounds play the most important role on the fouling and slagging behavior when co-firing. Some fusibility correlations that can assist in the elucidation of these behavior are presented and discussed, and then applied to the present study. Results show that for a biomass thermal share up to 20%, significant changes are not expected in fouling and slagging behavior of ash. (author)

  1. Preliminary results of field mapping of methane plumes offshore of Coal Oil Point, California with a RESON 7125 multibeam sonar in water-column mode

    Finlayson, D. P.; Hatcher, G.; Lorenson, T. D.; Greinert, J.; Maillard, E.; Weirathmueller, M.; Leifer, I.


    From June 17 - 23 2010, the U. S. Geological Survey (USGS) in collaboration with the Bureau of Ocean Energy Management Regulation and Enforcement(BOEMRE), the Royal Netherlands Institute for Sea Research (NIOZ) , RESON Inc. and the University of California, Santa Barbara(UCSB) conducted a comprehensive marine-seep gas-plume mapping study offshore of Coal Oil Point, California. The ultimate goal of the experiment is to quantify the amount of methane emitted from natural seeps using multibeam sonar, with results calibrated using field measurements of aqueous and atmospheric methane in the seep fields. Success will lead to better estimates of natural marine methane contributions to the global methane budget. We mapped selected seeps, some twice, with a pole-mounted RESON 7125 multibeam with a 10-degree forward rake. Other equipment included a Benthos Stingray ROV equipped with high-definition video cameras and in situ gas sampling apparatus, Niskin bottles for water column sampling of dissolved methane, and a Picarro G1301 cavity ringdown spectrometer for mapping atmospheric methane concentrations. This paper focuses primarily on the data reduction and data visualization strategies employed while processing the more than 1.2 TB of raw water column data collected by the multibeam system over several high-output oil and gas seep areas. Water depths ranged from about 30 to 80m. Turnkey software solutions for processing these data are currently unavailable so most of the processing code was developed in-house by the USGS. The main challenge in processing the sonar water-column data is ray-tracing the large volume of data, with each ping containing more than 4500 times as many samples as a conventional multibeam ping. We employed two strategies to make processing tractable on conventional workstations: (1) decimate the raw data based on desired output resolution before ray-tracing; and (2) design the ray-tracing program to run in parallel on multi-core workstations

  2. Experimental and theoretical investigation on unburned coal char burnout in a pilot-scale rotary kiln

    Federico Cangialosi; Francesco Di Canio; Gianluca Intini; Michele Notarnicola; Lorenzo Liberti; Giulio Belz; Pompilio Caramuscio [Technical University of Bari, Taranto (Italy). Department of Environmental Engineering and Sustainable Development


    Oxidation reactivity studies are imperative for improving carbon re-burn technologies and valuing the heat content of unburned carbon within coal combustion ashes. Non-isothermal, thermal gravimetric analysis (TGA) was used to examine the oxidation kinetics of unburned carbon in coal combustion fly ashes having different particle size distributions; TGA results were related to combustion efficiencies as measured in a bench-scale rotary kiln. The activation energy and pre-exponential factor were determined for the chemically-controlled reaction regime; the transition temperatures between chemically-controlled and partially diffusion-controlled combustion regimes were obtained for unburned carbon particles of different sizes. After the oxidation reaction rates were evaluated, the residence time distribution (RTD) of fly ashes in the rotary kiln were experimentally measured and the mean residence times related to process parameters, including the rotating velocity and kiln inclination. By comparing these results with an advective-dispersive model, the axial dispersion coefficient of fly ashes was determined. The reaction rates obtained by thermal analyses and the RTDs were used to predict combustion efficiencies within the kiln and oxidation conditions of unburned carbon using various processing options. 21 refs., 6 figs., 4 tabs.

  3. Experimental study on cement clinker co-generation in pulverized coal combustion boilers of power plants.

    Wang, Wenlong; Luo, Zhongyang; Shi, Zhenglun; Cen, Kefa


    The idea to co-generate cement clinker in pulverized coal combustion (PCC) boilers of power plants is introduced and discussed. An experimental study and theoretical analysis showed this idea to be feasible and promising. By adding quick lime as well as other mineralizers to the coal and grinding the mixture before combustion, sulfoaluminate cement clinker with a high content of silicate (SCCHS) could be generated. The main mineral phases in SCCHS are 2CaO x SiO2 (dicalcium-silicate), 3CaO x 3Al2O3 x CaSO4 (calcium-sulfoaluminate) and 2CaO x A12O3 SiO2 (gehlenite). Performance tests showed that the SCCHS met the requirements for utilization in common construction. Based on this idea, zero solid waste generation from PCC would be realized. Furthermore, thermal power production and cement production could be combined, and this would have a significant effect on both environmental protection and natural resource saving.

  4. Wall heat transfer coefficient in a molten salt bubble column: testing the experimental setup

    Skosana, PJ


    Full Text Available reactors that are highly exothermic or endothermic. This paper presents the design and operation of experimental setup used for measurement of the heat transfer coefficient in molten salt media. The experimental setup was operated with tap water, heat...

  5. Three-dimensional experimental study of loose top-coal drawing law for longwall top-coal caving mining technology

    Jiachen Wang; Jinwang Zhang; Zhengyang Song; Zhaolong Li


    Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving (LTCC) mining technology is studied by using self-developed three-dimensional (3D) test device. The loose top-coal drawing test with shields and the controlled test without shields are performed in the condition without any boundary effect. Test results show that shields will cause reduction in drawing volume of coal in the LTCC mining. The deflection phenomenon of drawing body is also observed in the controlled test, which is verified that the deflection of drawing body is caused by shield. It is found that the deflection angle decreases with increasing caving height, with the maximum value of atail and the minimum value of 0. In addition, the formula to calculate the drawing volume is proposed subsequently. The deflection of drawing body is numerically simulated using particle flow code PFC3D and the proposed formula to calculate drawing volume in LTCC is also verified.

  6. Reactive transport of gentisic acid in a hematite-coated sand column: Experimental study and modeling

    Hanna, K.; Rusch, B.; Lassabatere, L.; Hofmann, A.; Humbert, B.


    The adsorption of gentisic acid (GA) by hematite nano-particles was examined under static and dynamic conditions by conducting batch and column tests. To simulate natural sediments, the iron oxide was deposited on 10 μm quartz particles. The GA adsorption was described by a surface complexation model fitted to pH-adsorption curves with GA concentrations of 0.1-1 mM in a pH range of 3-10. The surface was described with one type of site ( tbnd FeOH°), while gentisic acid at the surface was described by two surface complexes ( tbnd FeLH 2°, log Kint = 8.9 and tbnd FeLH -, log Kint = -8.2). Modeling was conducted with PHREEQC-2 using the MINTEQ database. From a kinetic point of view, the intrinsic chemical reactions were likely to be the rate-limiting step of sorption (˜10 -3 s -1) while external and internal mass transfer rates (˜10 2 s -1) were much faster. Under flow through conditions (column), adsorption of GA to hematite-coated sand was about 7-times lower than under turbulent mixing (batch). This difference could not be explained by chemical adsorption kinetics as shown by test calculations run with HYDRUS-1D software. Surface complexation model simulations however successfully described the data when the surface area was adjusted, suggesting that under flow conditions the accessibility to the reactive surface sites was reduced. The exact mechanism responsible for the increased mobility of GA could not be determined but some parameters suggested that decreased external mass transfer between solution and surface may play a significant role under flow through conditions.

  7. Experimental investigation on NO{sub x} emission and carbon burnout from a radially biased pulverized coal whirl burner

    Xue, Shan; Hui, Shi' en; Zhou, Qulan; Xu, Tongmo; Hu, Hongli [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Taisheng [Dongfang Boiler Group Co., Ltd., Zigong, Sichuan 643001 (China)


    Experiments have been performed on 1 MW pulverized coal (pc) furnace in order to investigate the characteristics of coal combustion and NO{sub x} emission from a new type of radially biased dual register whirl burner. The burner is characterized by a primary air pipe with a continuously changing cross-section and an impact ring. The mixture of pulverized coal and air inside the primary pipe is split into two streams, which are the outer pc rich annular jet and the inner pc lean annular jet respectively. Three Chinese coals, which are high rank bituminous coal, low rank bituminous coal and meager coal respectively, are used in the experiments. We examine the influences of various parameters such as the relative position of the over-fire air (OFA) nozzle, over-fire air ratio (19.1%), primary air ratio, inner secondary air ratio, outer secondary air ratio, inner secondary air swirling intensity, and outer secondary air swirling intensity on NO{sub x} formation and unburned carbon in fly ash. With the primary air ratio increasing from 13.4% to 23.4%, the value of the NO{sub x} emission of the SH coal decreases by 26.7% at first, and then increases by 21.7%. In contrast, the value of the carbon in fly ash (C{sub FA}) increases by 40.1% at first, and then decreases by 58.3%. According to the experimental results, the influence of each individual parameter on NO{sub x} formation and unburned carbon in fly ash agrees well with the existing literature. In this study, the influences of various combinations of these parameters are also examined, thus providing some reference for the design of the radial biased whirl burner, the configuration of the furnace and the distribution of the air. (author)

  8. Macro- and microscopic mechanical behaviour of flow of coal samples experimentally deformed at high temperatures and pressures

    LIU Junlai; YANG Guang; MA Rui


    Coal samples from Qinshui Basin, Shanxi,China are experimentally deformed at temperatures and confining pressures of 200-500 ℃ and 200-500 Mpa,strain rate of 0.5×10-5/s and total strain of 10%. The vitrinite reflectance of the coal samples varies from 3.04 to 1.79. It is shown that the strengths of the deformed samples change obviously with coeval increasing temperatures and pressures (T/P). At the experimental range of T/P, the effects of increasing temperature predominate over that of increasing pressure. Microstructural analysis indicates a brittle to ductile transition under experimental T/P conditions from 200 to 300℃, and 200 to 300Mpa. Brittle deformation microstructures include macroscopic fracture zones and penetrative fracture associations. Elongation, undulose or irregular extinction, deformation lamellae and dynamic recrystallization of grains are the main ductile deformation microstructures.The variation of deformation mechanisms of the experimentally deformed coal samples is related to both the components of coals and T/P conditions. At low T/P, fractures occur in both inertinite and vitrinite of the samples. At higher T/P,crystalline plastic deformations are observed in the inertinite only.

  9. Prediction of oxygen concentration and temperature distribution in loose coal based on B P neural network

    ZHANG Yong-jian; WU Guo-guang; XU Hong-feng; MENG Xian-liang; WANG Guang-you


    An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we de-signed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal (13-25 ram) covered with fine coal (0-3 mm). A BP artificial neural network (ANN) with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal-6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the predic-tion of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 ~C, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles.

  10. Experimental Study on the Residual Strength of Coal Under Low Confinement

    Gao, Fuqiang; Kang, Hongpu


    In underground coal mining, coal rib failure of longwall entries is almost certain due to the relative weakness of coal and the presence of high mining-induced stresses. To maintain the coal's capability of sustaining large loads after failure and substantial deformation, it is crucial to understand its post-peak behavior and subsequently, its residual strength. In this study, triaxial compression tests were performed on a total of 51 coal specimens that were classified into two groups based on the existence of calcite grains. Particular emphasis was given to evaluating the residual strength of the coal specimens. It was found that the presence of calcite grains has significant effect on the brittleness of the coal. Coal specimens containing calcite grains have lower frictional strength than specimens without calcite grains. The tests demonstrated that splitting is completely suppressed when the confinement exceeds 10 % of the coal's unconfined compressive strength. The Coulomb and Hoek-Brown failure criteria satisfactorily fit the coals' the peak strength data over the entire confining stress range. The Hoek-Brown failure criterion satisfactorily fits the residual strength data. The parameter m for residual strength is significantly greater than that of the peak strength for both groups of coal. It was also found that as the confinement increases, the increase in residual strength is greater than the increase in peak strength.


    Lambert, D.; Choi, A.


    This report summarizes the results of both experimental and modeling studies performed using Sludge Batch 10 (SB10) simulants and FBSR product from Tank 48 simulant testing in order to develop higher levels of coal-carbon that can be managed by DWPF. Once the Fluidized Bed Steam Reforming (FBSR) process starts up for treatment of Tank 48 legacy waste, the FBSR product stream will contribute higher levels of coal-carbon in the sludge batch for processing at DWPF. Coal-carbon is added into the FBSR process as a reductant and some of it will be present in the FBSR product as unreacted coal. The FBSR product will be slurried in water, transferred to Tank Farm and will be combined with sludge and washed to produce the sludge batch that DWPF will process. The FBSR product is high in both water soluble sodium carbonate and unreacted coal-carbon. Most of the sodium carbonate is removed during washing but all of the coal-carbon will remain and become part of the DWPF sludge batch. A paper study was performed earlier to assess the impact of FBSR coal-carbon on the DWPF Chemical Processing Cell (CPC) operation and melter off-gas flammability by combining it with SB10-SB13. The results of the paper study are documented in Ref. 7 and the key findings included that SB10 would be the most difficult batch to process with the FBSR coal present and up to 5,000 mg/kg of coal-carbon could be fed to the melter without exceeding the off-gas flammability safety basis limits. In the present study, a bench-scale demonstration of the DWPF CPC processing was performed using SB10 simulants spiked with varying amounts of coal, and the resulting seven CPC products were fed to the DWPF melter cold cap and off-gas dynamics models to determine the maximum coal that can be processed through the melter without exceeding the off-gas flammability safety basis limits. Based on the results of these experimental and modeling studies, the presence of coal-carbon in the sludge feed to DWPF is found to have

  12. Experimental and computational study and development of the bituminous coal entrained-flow air-blown gasifier for IGCC

    Abaimov, N. A.; Osipov, P. V.; Ryzhkov, A. F.


    In the paper the development of the advanced bituminous coal entrained-flow air- blown gasifier for the high power integrated gasification combined cycle is considered. The computational fluid dynamics technique is used as the basic development tool. The experiment on the pressurized entrained-flow gasifier was performed by “NPO CKTI” JSC for the thermochemical processes submodel verification. The kinetic constants for Kuznetsk bituminous coal (flame coal), obtained by thermal gravimetric analysis method, are used in the model. The calculation results obtained by the CFD model are in satisfactory agreements with experimental data. On the basis of the verified model the advanced gasifier structure was suggested which permits to increase the hydrogen content in the synthesis gas and consequently to improve the gas turbine efficiency. In order to meet the specified requirements vapor is added on the second stage of MHI type gasifier and heat necessary for air gasification is compensated by supplemental heating of the blasting air.

  13. Experimental investigations on combustion and emission behaviour during oxy-coal combustion

    Dhungel, Bhupesh


    As the most abundant non-renewable energy source available, coal has traditionally played a major role in ensuring the security of energy, and will continue to play a key role in the world energy mix. The burning of coal has however always been a subject of environmental concern. In recent years, the emission of green house gases and global climate change has emerged as the largest environmental challenge. As coal fired power plants are categorised among the least carbon efficient energy prod...


    Donna Post Guillen; Daniel S. Wendt


    The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.


    Donna Post Guillen; Daniel S. Wendt; Steven P. Antal; Michael Z. Podowski


    The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.

  16. Effects of intermittent traction therapy in an experimental spinal column model.

    Shin, Jeong-Hun; Jun, Seung-lyul; Lee, Young-Jun; Kim, Jae-Hyo; Hwang, Sung-Yeoun; Ahn, Seong-Hun


    Traction therapy, which is known to be a treatment method for scoliosis, one of many muscles disease, has been used since Hippocrates introduced it. However, the effects of traction therapy are still not clear. In addition, the meridian sinew theory, which is related to muscle treatment and is mentioned in the book on meridian sinews in the Miraculous Pivot of Huangdi's Internal Classic, has not been the subject of much study. For these reasons, experimental spinal models were made for this study to observe and analyze the lengths of vertebral interspaces after intermittent traction therapy, which is known to be excellent among muscle treatment methods, with various tensile forces. The results showed that the effects of intermittent traction therapy were unclear and that it might be harmful, especially when the pain was induced by muscle weakness. Because the results of this study on intermittent traction therapy were different from those expected from osteopathy or craniosacral theory, better studies of the subject are necessary.

  17. Experimental and modeling study of the effect of CH(4) and pulverized coal on selective non-catalytic reduction process.

    Zhang, Yanwen; Cai, Ningsheng; Yang, Jingbiao; Xu, Bo


    The reduction of nitric oxide using ammonia combined with methane and pulverized coal additives has been studied in a drop tube furnace reactor. Simulated flue gas with 1000 ppm NO(x) and 3.4% excess oxygen was generated by cylinder gas. Experiments were performed in the temperature range of 700-1200 degrees C to investigate the effects of additives on the DeNO(x) performance. Subsequently, a kinetic mechanism was modified and validated based on experimental results, and a computational kinetic modeling with CHEMKIN was conducted to analyze the secondary pollutants. For both methane and pulverized coal additives, the temperature window is shifted towards lower temperatures. The appropriate reaction temperature is shifted to about 900 and 800 degrees C, respectively with 1000 ppm methane and 0.051 g min(-1) pulverized lignite coal. The addition of methane and pulverized coal widens the temperature window towards lower temperature suggesting a low temperature application of the process. Furthermore, selective non-catalytic reduction (SNCR) reaction rate is accelerated evidently with additives and the residence time to complete the reaction is shortened distinctly. NO(x) reduction efficiency with 80% is achieved in about 0.3s without additive at 1000 degrees C. However, it is achieved in only about 0.2s with 100 ppm methane as additive, and only 0.07 and 0.05s are needed respectively for the cases of 500 and 1000 ppm methane. The modified kinetic modeling agrees well with the experimental results and reveals additional information about the process. Investigation on the byproducts where NO(2) and N(2)O were analyzed by modeling and the others were investigated by experimental means indicates that emissions would not increase with methane and pulverized coal additions in SNCR process and the efficacious temperature range of SNCR reaction is widened approximately with 100 degrees C.


    Subha K. Kumpaty; Kannikeswaran Subramanian; Victor P. Nokku; Tyrus L. Hodges; Adel Hassouneh; Ansumana Darboe; Sravan K. Kumpati


    In this work, both computer simulation and experimental studies were conducted to investigate several strategies for NO{sub x} reduction under pulverized coal combustion conditions with an aim to meet the stringent environmental standards for NO{sub x} control. Both computer predictions and reburning experiments yielded favorable results in terms of NO{sub x} control by reburning with a combination of methane and acetylene as well as non-selective catalytic reduction of NO{sub x} with ammonia following reburning with methane. The greatest reduction was achieved at the reburning stoichiometric ratio of 0.9; the reduction was very significant, as clearly shown in Chapters III and V. Both the experimental and computational results favored mixing gases: methane and acetylene (90% and 10% respectively) and methane and ammonia (98% and 2%) in order to get optimum reduction levels which can not be achieved by individual gases at any amounts. Also, the above gaseous compositions as reburning fuels seemed to have a larger window of stoichiometric ratio (SR2 < 0.9) as opposed to just methane (SR2=0.9) so as to reduce and keep NO{sub x} at low ppm levels. From the various computational runs, it has been observed that although there are several pathways that contribute to NO{sub x} reduction, the key pathway is NO {r_arrow} HCN {r_arrow} NH{sub 3} {r_arrow} N{sub 2} + H{sub 2}. With the trends established in this work, it is possible to scale the experimental results to real time industrial applications using computational calculations.

  19. Experimental study of the cultivation and application of fungus for transformation and biodegradation of coal

    Wang Long-qui; Zhang Ming-xu; Ou Ze-shen; Shen Guo-juan [Anhui University of Science and Technology, Huainan (China). Departmental of Material Science & Engineering


    By microoganic fungus cultivation, three kinds of epiphyte were selected for the experiments of coal biodegradation and transformation. The influences of key factors, such as fungus type, size and rank of coal, and pretreatment, on coal degradation were studied. Results show that the best degradation result of 38.13% within 10 days is achieved under co-cultivation of the three kinds of epiphyte for Yima lignite. The finer the coal particle is, the higher the percentage of degradation is, the lower the degree of metamorphism of the coal is, the easier the coal is degraded by the fungus, and the pretreated coal generally tended to be more easily degraded. The degradation products were analysed using XRD and FTIR, and the results show that the degree of the polymerigation of the aromatic nucleus and the molecular weights of products as well are decreased obviously, and remarkable changes also take place in the content of functional groups compared with the coal. 11 refs., 7 figs., 6 tabs.

  20. Organic Matter Transformation in the Peat Column at Marcell Experimental Forest: Humification and Vertical Stratification

    Tfaily, Malak [Florida State University, Tallahassee; Cooper, Bill [Florida State University, Tallahassee; Kostka, [Georgia Institute of Technology, Atlanta; Chanton, Patrick R [ORNL; Schadt, Christopher Warren [ORNL; Hanson, Paul J [ORNL; Iversen, Colleen M [ORNL; Chanton, Jeff P [ORNL


    A large-scale ecosystem manipulation (Spruce and Peatland Responses under Climatic and Environmental Change, SPRUCE) is being constructed in the Marcell Experimental Forest, Minnesota, USA, to determine the effects of climatic forcing on ecosystem processes in northern peatlands. Prior to the initiation of the manipulation, we characterized the solid-phase peat to a depth of 2 meters using a variety of techniques, including peat C:N ratios, 13C and 15N isotopic composition, Fourier Transform Infrared (FT IR), and 13C Nuclear Magnetic Resonance spectroscopy (13C NMR). FT IR determined peat humification-levels increased rapidly between and 75 cm, indicating a highly reactive zone. We observed a rapid drop in the abundance of O-alkyl-C, carboxyl-C, and other oxygenated functionalities within this zone and a concomitant increase in the abundance of alkyl- and nitrogen-containing compounds. Below 75-cm, minimal change was observed except that aromatic functionalities accumulated with depth. Incubation studies revealed the highest methane production rates and greatest CH4:CO2 ratios within this and 75 cm zone. Hydrology and surface vegetation played a role in belowground carbon cycling. Radiocarbon signatures of microbial respiration products in deeper porewaters resembled the signatures of dissolved organic carbon rather than solid phase peat, indicating that more recently photosynthesized organic matter fueled the bulk of subsurface microbial respiration. Oxygen-containing functionalities, especially O-alkyl-C, appear to serve as an excellent proxy for soil decomposition rate, and in addition should be a sensitive indicator of the response of the solid phase peat to the climatic manipulation.

  1. Experimental Study on a Self-Centering Earthquake-Resistant Masonry Pier with a Structural Concrete Column

    Lijun Niu


    Full Text Available This paper proposes a slotting construction strategy to avoid shear behavior of multistory masonry buildings. The aspect ratio of masonry piers increases via slotting between spandrels and piers, so that the limit state of piers under an earthquake may be altered from shear to rocking. Rocking piers with a structural concrete column (SCC form a self-centering earthquake-resistant system. The in-plane lateral rocking behavior of masonry piers subjected to an axial force is predicted, and an experimental study is conducted on two full-scale masonry piers with an SCC, which consist of a slotting pier and an original pier. Meanwhile, a comparison of the rocking modes of masonry piers with an SCC and without an SCC was conducted in the paper. Experimental verification indicates that the slotting strategy achieves a change of failure modes from shear to rocking, and this resistant system with an SCC incorporates the self-centering and high energy dissipation properties. For the slotting pier, a lateral story drift ratio of 2.5% and a high displacement ductility of approximately 9.7 are obtained in the test, although the lateral strength decreased by 22.3% after slotting. The predicted lateral strength of the rocking pier with an SCC has a margin of error of 5.3%.

  2. Experimental and numerical studies of the chromatofocusing of dilute proteins using retained pH gradients formed on a strong-base anion-exchange column.

    Strong, J C; Frey, D D


    The separation of dilute protein mixtures was achieved using simple monovalent buffering species to form retained, internally produced pH gradients on a strong-basic anion-exchange column. Highly focused proteins bands localized on stepwise pH transitions were produced experimentally under trace and volume overloaded feed conditions. Numerical simulations were performed that accurately predict the pH profile and protein band shapes in the column effluent. Experimental results were combined with numerical investigations to explore strategies for designing efficient preparative-scale chromatofocusing systems using simple, inexpensive buffers and adsorbents.

  3. Three-column intermittent simulated moving bed chromatography: 2. Experimental implementation for the separation of Tröger's Base.

    Jermann, Simon; Alberti, Andreas; Mazzotti, Marco


    The three-column intermittent simulated moving bed (3C-ISMB) process has been presented in the first part of this series [1]. A theoretical comparative analysis of the new process to intermittent simulated moving bed (I-SMB) demonstrated successfully the potential of the 3C-ISMB technology. Particularly, 3C-ISMB was shown to substantially outperform I-SMB in terms of productivity whilst maintaining high purity specifications and without significantly sacrificing solvent consumption. Moreover, we demonstrated the applicability of Triangle Theory for 3C-ISMB design, which is an important advantage compared to other modified SMB schemes. In the present work we report on the experimental implementation of the 3C-ISMB technology demonstrating the simplicity of retrofitting an existing SMB or I-SMB plant. Moreover, we perform an experimental comparative analysis studying the well-known separation of Tröger's Base enantiomers in pure ethanol on Chiralpak AD™. In a comprehensive series of experimental runs, each examining three different modes of operation, applying total feed concentrations ranging from 5 g/l to 17.4 g/l, we assess and compare the separation performances of both conventional I-SMB and 3C-ISMB. This series of experiments successfully demonstrates that 3C-ISMB delivers the same high purity levels as conventional I-SMB whilst significantly outperforming the conventional process in terms of productivity; in fact an increase of more than 80% is achieved. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Experimental study on the type change of liquid flow in broken coal samples

    Lu-zhen WANG; Zhan-qing CHEN; Hai-de SHEN


    A test system of the permeability of broken coal samples mainly consists of a CMT5305 electronic universal test machine,crushed rock compaction containing cylinder and a self-designed seepage circuit,which is composed of a gear pump,a reversing valve,a relief valve and other components.By using the steady penetration method,the permeability and non-Darcy flow β factor of broken coal samples under five different porosity levels were measured,the grain diameters of the coal samples were selected as 2.5-5 mm,5-10 mm,10-15 mm,15-20 mm,20-25 mm and 2.5-25 mm,respectively.After measuring the permeability under each porosity,the overfall pressure of the relief valve continuously increased until the coal sample was broken down.In this way,the flow type of liquid inside the broken coal samples changed from seepage to pipe flow.The correlation between breakdown pressure gradient (BPG) and porosity was analyzed,and the BPG was compared with the pressure gradient when seepage instability occurred.The results show that,① the non-Darcy flow β factor was negative before broken coal samples with six kinds of diameters were broken down; ② the BPG of coal samples with a grain size of 2.5-25 mm was lower than that of the others; ③ the BPG of coal samples with a single diameter under the same porosity increased as the grain size increased; ④ the BPG could be fitted by an exponential function with porosity,and the exponent decreased as the grain size increased for coal samples with a single diameter; ⑤ the BPG was slightly less than the seepage instability pressure gradient.The change in liquid flow type from seepage to pipe flow could be regarded as the performance of the seepage instability.

  5. Evaluation of Biomass and Coal Briquettes for a Spreader Stoker Boiler Using an Experimental Furnace --- Modeling and Test

    Wiggins, Gavin Memminger

    The compliance of coal-fired boilers with emissions regulations is a concern for many facilities. The introduction of biomass briquettes in industrial boilers can help to reduce greenhouse gas emissions and coal usage. In this research project, a thermodynamic chemical equilibrium model was derived and analytical simulations performed for a coal boiler system for several types of biomass fuels such as beech, hickory, maple, poplar, white oak, willow, sawdust, torrefied willow, and switchgrass. The biomass emissions were compared to coal and charcoal emissions. The chemical equilibrium analysis numerically estimated the emissions of CO, CO2, NO, NO2, N 2O, SO2, and SO3. When examining the computer results, coal and charcoal emitted the highest CO, CO2, and SO x levels while the lowest (especially for SOx) were reached by the biomass fuels. Similarly, NOx levels were highest for the biomass and lowest for coal and charcoal. To validate these analytical results, a custom traveling grate furnace was designed and fabricated to evaluate different types of biofuels in the laboratory for operation temperatures and emissions. The furnace fuels tested included coal, charcoal, torrefied wood chips, and wood briquettes. As expected, the coal reached the highest temperature while the torrefied wood chips offered the lowest temperature. For CO and NO x emissions, the charcoal emitted the highest levels while the wood briquettes emitted the lowest levels. The highest SO2 emissions were reached by the coal while the lowest were emitted by the wood briquettes. When compared to the coal fuel, charcoal emissions for CO increased by 103%, NO and NOx decreased by 21% and 20% respectively, and SO2 levels decreased by 92%. For torrefied wood, emissions for CO increased by 17%, NO and NOx decreased by 58% and 57% respectively, and SO 2 decreased by 90%. For wood briquettes, emissions for CO decreased by 27%, NO and NOx decreased by 66%, and SO2 levels decreased by 97%. General trends in

  6. An experimental study on the law of methane outflow in coal face

    WANG Jian; WEI Yin-shang


    Work face 3312 of coal mining in a colliery was taken as an example in whichmethane data in a series of locations was analyzed. For the purpose of data analysis,work face 3312 was divided into sections with 20 powered supports and some measur-ing-points in a section. Through analysis based on the sectional control volume model, thefollowing points are concluded: (1) the location of gob air flow begins flow into coal face in70 m away from the haulage gallery; (2) in the control volumes No.10 and No.30, the ra-tios of methane intensity from coal face into gob to the methane intensity in the corre-sponding control volume are 30% and 22%; (3) in the control volume No.50 to No.110, theratios of methane intensity from gob into coal face to the methane intensity in the corre-sponding control volume are 4%, 17%, 22% and 53%, respectively.

  7. Experimental study on performance that carbon dioxide inhibits coal oxidation and spontaneous combustion

    DENG Jun; LI Shi-rong; ZHANG Yan-ni; MU Ying; ZHANG Yang


    Adopting oil-bath temperature programming experiment and gas chromatography,CO2's inhibitory performance on spontaneous combustion of Tingnan Coal Mine sample was analyzed.Through temperature rise rate test experiment,the accuracy,stability and reliability of the improved oil-bath temperature programming system applied in this experiment was proved to be superior to the traditional system.Spontaneous combustion characters parameters test of coal sample in pure air was carried out with this system and offered comparison standard for research in next stage.Temperature programming to coal sample was further conducted in oil-bath with different concentration of CO2.Testing results are compared with parameters of concentration of CO,O2,temperature,CO generation rate and O2 consumption rate tested and calculated in previous experiment in pure air.Methods of proportioning between concentration of CO and O2,CO concentration and temperature,CO generation rate and O2 consumption rate were applied to eliminate obstructions from certain external factors such as inlet of CO2; meanwhile influences of CO2 of different concentrations to coal oxidation and spontaneous combustion were investigated.Also CO2 inhibition technique was used in spontaneous combustion prevention in workface No.106 of Tingnan Coal Mine,data collected from which indicate that CO2 performs well in inhibiting coal oxidation and spontaneous combustion.

  8. Chemometric Study of the Ex Situ Underground Coal Gasification Wastewater Experimental Data.

    Smoliński, Adam; Stańczyk, Krzysztof; Kapusta, Krzysztof; Howaniec, Natalia


    The main goal of the study was the analysis of the parameters of wastewater generated during the ex situ underground coal gasification (UCG) experiments on lignite from Belchatow, and hard coal from Ziemowit and Bobrek coal mines, simulated in the ex situ reactor. The UCG wastewater may pose a potential threat to the groundwater since it contains high concentrations of inorganic (i.e., ammonia nitrogen, nitrites, chlorides, free and bound cyanides, sulfates and trace elements: As, B, Cr, Zn, Al, Cd, Co, Mn, Cu, Mo, Ni, Pb, Hg, Se, Ti, Fe) and organic (i.e., phenolics, benzene and their alkyl derivatives, and polycyclic aromatic hydrocarbons) contaminants. The principal component analysis and hierarchical clustering analysis enabled to effectively explore the similarities and dissimilarities between the samples generated in lignite and hard coal oxygen gasification process in terms of the amounts and concentrations of particular components. The total amount of wastewater produced in lignite gasification process was higher than the amount generated in hard coal gasification experiments. The lignite gasification wastewater was also characterized by the highest contents of acenaphthene, phenanthrene, anthracene, fluoranthene, and pyrene, whereas hard coal gasification wastewater was characterized by relatively higher concentrations of nitrites, As, Cr, Cu, benzene, toluene, xylene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, and benzo(a)pyrene.

  9. Experimental Study on Formation of Particle Accumulation Structures by a Thermocapillary Flow in a Deformable Liquid Column

    Melnikov, D. E.; Watanabe, T.; Matsugase, T.; Ueno, I.; Shevtsova, V.


    A series of experiments has been performed under earth's gravity to study formation of particle accumulation structures (PAS) in a supercritical flow driven by the combined effects of buoyancy and thermocapillary forces. The test flow was created in a non-isothermal cylindrical column (liquid bridge) made of n-decane and heated from above. The objective of the experiment was to answer two major questions: (1) how strong is the influence of the shape of the interface on the process of formation of PAS; (2) what temperature of the ambient air fits better for PAS to occur. Considering these questions, we developed a method based on changing both the volume of the liquid bridge and temperature at the external walls of the experimental chamber to set and to keep constant the shape of the interface and the temperature inside the setup, respectively. The experimental observations are presented in the form of diagrams in the parameters' space showing ranges of the PAS formation. The findings show that a liquid bridge with an interface as close to the straight cylindrical as possible and surrounded by air at low temperature is the best terrain for PAS formation. The results of the chaos analysis of the recorded temperature time series and their correlation with the obtained diagrams allow for showing that accumulation of particles in coherent structures is possible only in a periodic oscillatory flow characterized by a small value of the translation error not exceeding 0.01. It is demonstrated that presence of either any spectral noise or of several modes with incommensurate frequencies makes formation of a PAS impossible.

  10. Experimental Evaluation of the Failure of a Seismic Design Category - B Precast Concrete Beam-Column Connection System


    specimen to examine the specimen, but not inside the reaction frame . 8. The load will removed from the stub column, and the specimen will be braced to...experiment to test a precast concrete beam-column system to failure. This experiment was designed to evaluate the performance of precast frame ...54  Figure 81. Strains in top lateral steel brace beam

  11. Evaluation of ash deposits during experimental investigation of co-firing of Bosnian coal with wooden biomass

    Smajevic, Izet; Kazagic, Anes [JP Elektroprivreda BiH d.d., Sarajevo (Bosnia and Herzegovina); Sarajevo Univ. (Bosnia and Herzegovina). Faculty of Mechanical Engineering


    The paper is addressed to the development and use different criteria for evaluation of ash deposits collected during experimental co-firing of Bosnian coals with wooden biomass. Spruce saw dust was used for the co-firing tests with the Kakanj brown coal and with a lignite blend consisted of the Dubrave lignite and the Sikulje lignite. The coal/biomass mixtures at 93:7 %w and at 80:20 %w were tested. Experimental lab-scale facility PF entrained flow reactor is used for the co-firing tests. The reactor allows examination of fouling/slagging behaviors and emissions at various and infinitely variable process temperature which can be set at will in the range from ambient to 1560 C. Ash deposits are collected on two non-cooled ceramic probes and one water-cooled metal surface. Six different criteria are developed and used to evaluate behavior of the ash deposits on the probes: ash deposit shape, state and structure, which are analyzed visually - photographically and optically by a microscope, rate of adhesion and ash deposit strength, analyzed by physic acting to the ash deposits, and finally deposition rate, determined as a mass of the deposit divided by the collecting area and the time of collecting. Furthermore, chemical composition analysis and AFT of the ash deposits were also done to provide additional information on the deposits. (orig.)

  12. The industrial practice and development of flotation column in China

    Liu Jiongtian; Zhang Shuangquan [China Univ. of Mining and Technology, Xuzhou (China). Dept. of Energy Utilization and Chemical Engineering


    This paper reviewed the developing course of the flotation column since the 1960`s in China. Based on the practical data from several coal preparation plants, two types of flotation columns (the pressure aerated column and the jetting-cyclone column) were compared by their operation, performance and the reasons why they succeeded in the coal industry in China. The paper points out that the flotation column has come into commercial use and has good application prospects in China.

  13. A Study on the gas productivity by using Experimental Results of Stress-induced Permeability Change in Coal Seam

    Kang, I. O.; Kim, K. H.; Han, J. M.; Lee, S. M.


    Methane Production from coal has become one of the more interesting practices in recent years to produce hydrocarbons. In the United States in 2005, it is estimated that 11% of all gas produced is from coalbed. The permeability is a measure of the capability of a porous medium to transmit fluid thought a network of microscopic channels. The permeability in coal is a direct function of the cleat volume. Since the volume of cleat changes with effect on the effective stress and sorption characteristics for production duration, the permeability also produces the alteration. Thus, to definitely estimate the gas production ability of the coal, it is essential that we especially understand changing aspects of permeability for production duration. Many researchers suggested the empirical equation to describe the effect of matrix shrinkage and effective stress. However, the past research associated with permeability change in coal focused on experimental results at a certain temperature.In this study, we have investigated the change of the sorption-induced permeability in pressure change with depth, an experimental approach considering temperature influence at the certain depth may be followed. Based on the received core from CBM field, we conducted the experiment both sorption and permeability according to the various pressure and temperatures.Firstly, experiment of the CH4 sorption was performed in the temperature ranged from 59℉ to 113℉ in the pressure ranges from 14.7 psia to 1,299 psia. Ot was found that CH3 isotherms display a normal Langmuir-type behavior from experiment ranges. In order to understand the effect of adsorption of CH4 in the change of sorption-induced permeability, we measured the permeability at the various pressures. When the pressure was increased by 100 psia, the results showed that the permeability alteration rate was 9.7% in reduction. Meanwhile, the permeability change rate was higher for a better affinity gas at lower temperature. Based on

  14. Experimental Study on Properties of Methane Diffusion of Coal Block under Triaxial Compressive Stress

    Hong-Bao Zhao


    Full Text Available Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters.

  15. Experimental study on treatment of acetabular anterior column fractures: applyment of a minimally invasive percutaneous lag screw guide apparatus

    Zhang, Li-hai; Zhang, Li-cheng; Si, Qing-hua; Gao, Yuan; Su, Xiu-Yun; Zhao, Zhe; Tang, Pei-Fu


    Background The aim of this study was to design a new minimally invasive percutaneous lag screw guide apparatus and to verify its adjuvant treatment of acetabular anterior column fracture on pelvis specimens. Methods This guide apparatus was self-developed based on the principles of “two points form a line” and “Rectangle”. Using C-arm fluoroscopy, this guide apparatus was used to conduct minimally invasive percutaneous lag screw internal fixation of acetabular anterior column fractures. Ten h...

  16. Experimental study on the response characteristics of coal permeability to pore pressure under loading and unloading conditions

    Ye, Zhiwei; Zhang, Lei; Hao, Dingyi; Zhang, Cun; Wang, Chen


    In order to study the response characteristics of coal permeability to pore pressure, seepage experiments under different simulated in situ stresses on loading and unloading paths are carried out using the self-developed Gas Flow and Displacement Testing Apparatus (GFDTA) system. Based on the analysis of the experimental data, the relationship between average pore pressure and permeability is found to basically obey the function distribution of a two degree polynomial. In this paper, two aspects of the relationship between permeability and pore pressure are explained: the Klinbenberg effect and expansion, and the penetration of the initial fracture. Under low pore pressure, the decrease in the Klinbenberg effect is the main reason for the decrease in permeability with increased pore pressure. Under relatively high pore pressure, the increase in pore pressure leads to the initial fracture expansion and penetration of the coal sample, which causes an increase in permeability. In order to evaluate the sensitivity of the permeability response to pore pressure changes, the permeability dispersion and pore pressure sensitivity coefficients are defined. After the sensitivity analysis, it was concluded that the loading history changed the fracture structure of the original coal sample and reduced its permeability sensitivity to pore pressure. Under low pore pressure, the Klinbenberg effect is the reason for the decrease in pore pressure sensitivity. Lastly, the permeability-pore pressure relationship is divided into three stages to describe the different response characteristics individually.

  17. Experimental study on the removal of ammonia nitrogen and total nitrogen with algae from coal-gasification wastewater%藻类去除煤气化废水氨氮及总氮的实验研究

    刘肃力; 纪钦洪; 于广欣; 卿人韦


    The column photo-bioreactor has been used for algae removing ammonia nitrogen and total nitrogen with algae from coal-gasification wastewater.Experimental results show that under the optimized conditions,Scenedesmus quadricanda,Scnedesmus obliquus and compound algae (Tribonema and Phormidium) can make statistically thorough removal of the ammonia nitrogen from coal-gasification wastewater within 3 d,and the removing efficiency of total nitrogen from coal-gasification wastewater has reached the maximum on the 5th day,which is 86.02% with Scenedesmus quadricanda,83.33% with Senedesmus obliquus,and 71.81% with the compound algae.The results reveal that it is feasible to remove ammonia nitrogen and total nitrogen from coal gasification wastewater by using appropriate algae.Besides,compared with the biological nitrification/denitrification denitrogenation process,the process is also significantly original.%采用柱式光合反应器对藻类去除煤气化废水的氨氮及总氮开展了探索性实验研究.实验结果表明:优化条件下,四尾栅藻、斜生栅藻、混合藻(黄丝藻和席藻)都在3d内完全去除氨氮,同时总氮去除率都在第5天达到最大,分别是四尾栅藻86.02%,斜生栅藻83.33%,混合藻71.81%.说明选用合适的藻类去除煤气化废水的氨氮及总氮可行,同时相比生物硝化/反硝化脱氮工艺该方法具有一定的新颖性.

  18. Fluidised bed gasification of high-ash South African coals: An experimental and modelling study

    Engelbrecht, AS


    Full Text Available The gasification of two high-ash coals were studied using a pilot scale fluidised bed gasifier using oxygen enrich air and steam as the gasification agents. The results of the tests show that the fixed carbon conversion and calorific value increases...

  19. CO2-ECBM and CO2 Sequestration in Polish Coal Seam – Experimental Study

    Paweł Baran


    Originality/value: The results indicate successful sorption of carbon dioxide in each experiment. This provides the rationale to study the application of the coal tested to obtain methane genetic origin genetic methane with the use of the CO2 injection.

  20. Experimental studies on the physico-mechanical properties of jet-grout columns in sandy and silty soils

    Akin, Muge K.


    The term of ground improvement states to the modification of the engineering properties of soils. Jet-grouting is one of the grouting methods among various ground improvement techniques. During jet-grouting, different textures of columns can be obtained depending on the characteristics of surrounding subsoil as well as the adopted jet-grouting system for each site is variable. In addition to textural properties, strength and index parameters of jet-grout columns are highly affected by the adjacent soil. In this study, the physical and mechanical properties of jet-grout columns constructed at two different sites in silty and sandy soil conditions were determined by laboratory tests. A number of statistical relationships between physical and mechanical properties of soilcrete were established in this study in order to investigate the dependency of numerous variables. The relationship between qu and γd is more reliable for sandy soilcrete than that of silty columns considering the determination coefficients. Positive linear relationships between Vp and γd with significantly high determination coefficients were obtained for the jet-grout columns in silt and sand. The regression analyses indicate that the P-wave velocity is a very dominant parameter for the estimation of physical and mechanical properties of jet-grout columns and should be involved during the quality control of soilcrete material despite the intensive use of uniaxial compressive strength test. Besides, it is concluded that the dry unit weight of jet-grout column is a good indicator of the efficiency of employed operational parameters during jet-grouting.

  1. Flat-flame burner studies of pulverized-coal combustion. Experimental results on char reactivity

    Peck, R.E.; Shi, L.


    Structure of laminar, premixed pulverized-coal flames in a 1-D reactor has been studied with emphasis on char reactivity. A 1.1-meter-long tube furnace accommodated high-temperature environments and long residence times for the laminar flames produced by a flat-flame, coal-dust burner. Experiments were conducted at different operating conditions (fuel type/size, fuel-air ratio). Measurements included solid sample composition, major gas species and hydrocarbon species concentrations, and gas- and particle-phase line-of-sight temperatures at different axial locations in flames. Degree of char burnout increased with coal volatiles content and decreased with coal particle size. Combustion in furnace was in oxidizer-deficient environment and higher burnout was achieved as the fuel-air ratio neared stoichiometric. For 0-45 {mu}m particles most of the fixed carbon mass loss occurred within 5 cm of the furnace inlet, and char reaction was slow downstream due to low oxidizer concentrations. Fixed carbon consumption of the 45-90 {mu}m particles generally was slower than for the small particles. About 40%-80% of the fixed carbon was oxidized in the furnace. Primary volatiles mass loss occurred within the first 4.5 cm, and more than 90% of the volatiles were consumed in the flames. The flames stabilized in the furnace produced less CH{sub 4} and H{sub 2} in the burnt gas than similar unconfined flames. NO concentrations were found to decrease along the furnace and to increase with decreasing fuel/air ratio. Temperature measurement results showed that gas-phase temperatures were higher than solid-phase temperatures. Temperatures generally decreased with decreasing volatiles content and increased as the equivalence ratio approached one. The results can be used to interpret thermochemical processes occurring in pulverized-coal combustion. (au) 15 refs.

  2. An experimental investigation of innovative bridge columns with engineered cementitious composites and Cu-Al-Mn super-elastic alloys

    Hosseini, F.; Gencturk, B.; Lahpour, S.; Ibague Gil, D.


    Recent strong earthquakes have shown that reinforced concrete (RC) bridge columns constructed using conventional materials and techniques suffer from major damage and permanent deformations. The yielding of the longitudinal reinforcement as the main source of energy absorption, and cracking and spalling of concrete results in a dysfunctional bridge structure that does not support the post-disaster recovery efforts. This paper investigates the use of engineered cementitious composites (ECCs) and Cu-Al-Mn super-elastic alloys (SEAs) to improve the performance of bridge columns under seismic loads. A new column design is proposed, which is composed of a pre-fabricated ECC tube that encompasses the longitudinal and transverse steel reinforcement (rebar). The rebar in the plastic hinge region of the cantilever columns was totally or partially replaced with Cu-Al-Mn SEA bars. The tube was filled with conventional concrete after it was placed inside the rebar cage of the foundation. ECC exhibits superior tensile ductility, bonding with steel, energy absorption and shear resistance, in addition to lower permeability and reduced crack widths compared to conventional concrete. Cu-Al-Mn SEA bars are capable of recovering large inelastic deformations exceeding 12% strain. The proposed approach capitalizes on the deformability of ECC with reduced damage, and the energy absorption capacity of Cu-Al-Mn SEA bars without permanent deformation. A total of six column specimens were constructed and tested under simulated seismic loading. The number of rebars replaced with Cu-Al-Mn SEA bars, ECC mixture design, and the ratio of the concrete core area to total column cross-sectional area were the variables investigated in the test program. A comparison of the results indicated that the proposed concept with no Cu-Al-Mn SEA bars provides higher lateral strength, similar energy absorption and reduced damage compared to conventional RC columns; however, similar to a conventional column, it

  3. Experimental Study on Seismic Behavior of Exterior Joints of Special-shaped Columns with Different Lengths of Limbs


    Four exterior joints with special-shaped columns which have different lengths of limbs are tested under low cyclic loading. Special-shaped columns adopted are L- and T-shaped in section. It can be concluded that crack pattern, failure mode and shear strength of joints are affected by the length of limb, and that shear strength and ductility increase with the length of limb; the joints with the flexural failure of the beam have better seismic behavior than those with the shear failure of the joint core.

  4. Low—NOx Combustion and Experimental Investigation in a ROtary Type Pulverized Coal Classifier

    WenjunKong; ShangmoCheng; 等


    In order to improve the combustion conditions,maximize the carbon burnout for low-NOx firing systems and meet the requirements for ignition and flame stabilization as low volatile and low quality coal are burned in boilers,finer pulverzed coal should be used is of great practical importance to study the rotary type classifier for the MPS type medium-speed mill.In this pper,we first review the low-NOx combustion technology,then some model tests of rotating classifier are completed.The results show that the classifier performances are very satisfactory,with the fineness of the finished produce being R90f<10%,Rules for designing and controlling rotating classifier are also developed in this paper.

  5. Experimental Study on Roof Structure Characteristics and Its Failure Pattern in Coal Roadway

    薛亚东; 康天合; 黄宏伟


    Based on the investigation and statistics of logs of 211 bole holes and strata data from 79 roadways in 13 coal mines located in Xishan, Jincheng, Lu'an, Fenxi, and Huozhou in China, the roadways' roof structures were classified as multi-thin-layer, thin-thick combined layer, integrated thick layer, thick-coal layer, and cracked layer according to the geometric features and spatial strength distribution of surrounding rock. Then eight sub-categories were defined as different situations. And seven simulation modeling tests were carried out. The strata structures of these models were different from each other. At last, the relationship between roof structure and its failure pattern was discussed.

  6. The experimental study of the coal gangue as gel filling materials

    TIAN Dong-mei; YAO Jian; JIANG Zhong-an; WANG Xin-min; ZHANG Qin-li


    The odd axes resist pressure intensity with large quantity coal gangue was dis-cussed and experimented on fly ash and coal gangue gel filling body between different concentration, proportion and additive dosage. The results show that forepart intensity of new gangue filling body is very low, and anaphase intensity have some increase which still go up after sixty days. The intensity of tao gangue can reach 1.0 MPa in seven days, and anaphase intensity can reach about 2.0 MPa. In the same term, the odd axes resist pres-sure intensity of gel filling body with tao gangue is higher than new gangue No.1 and No.2.To mix into proper additive dosage which occupied the quality point of cement and fly ash not more than 1.5% can improve the fluidity of slurry body and intensity of filling body.

  7. Mercury Speciation in Coal-Fired Power Plant Flue Gas-Experimental Studies and Model Development

    Radisav Vidic; Joseph Flora; Eric Borguet


    The overall goal of the project was to obtain a fundamental understanding of the catalytic reactions that are promoted by solid surfaces present in coal combustion systems and develop a mathematical model that described key phenomena responsible for the fate of mercury in coal-combustion systems. This objective was achieved by carefully combining laboratory studies under realistic process conditions using simulated flue gas with mathematical modeling efforts. Laboratory-scale studies were performed to understand the fundamental aspects of chemical reactions between flue gas constituents and solid surfaces present in the fly ash and their impact on mercury speciation. Process models were developed to account for heterogeneous reactions because of the presence of fly ash as well as the deliberate addition of particles to promote Hg oxidation and adsorption. Quantum modeling was used to obtain estimates of the kinetics of heterogeneous reactions. Based on the initial findings of this study, additional work was performed to ascertain the potential of using inexpensive inorganic sorbents to control mercury emissions from coal-fired power plants without adverse impact on the salability fly ash, which is one of the major drawbacks of current control technologies based on activated carbon.

  8. Experimental Study on Coal Multi-generation in Dual Fluidized Beds

    Fan Xiaoxu; Lu Qinggang; Na Yongjie; Liu Qi


    An atmospheric test system of dual fluidized beds for coal multi-generation was built. One bubbling fluidized bed is for gasification and a circulating fluidized bed for combustion. The two beds are combined with two valves:one valve to send high temperature ash from combustion bed to the gasification bed and another valve to send char and ash from gasification bed to combustion bed. Experiments on Shenhua coal multi-generation were made at temperatures from 1112 K to 1191 K in the dual fluidized beds. The temperatures of the combustor are stable and the char combustion efficiency is about 98%. Increasing air/coal ratio to the fluidized bed leads to the increase of temperature and gasification efficiency. The maximum gasification efficiency is 36.7% and the calorific value of fuel gas is 10.7 MJ/Nm3. The tar yield in this work is 1.5%, much lower than that of pyrolysis.Carbon conversion efficiency to fuel gas and flue gas is about 90%.

  9. Experimental and Particle-Tracking Model Analysis of Anomalous Transport and Sorption of Nickel in Natural Soil Columns

    Edery, Y.; Rubin, S.; Dror, I.; Berkowitz, B.


    Nickel migration measured in laboratory-scale, natural soil column experiments is shown to display anomalous (non-Fickian) transport and non-equilibrium adsorption and desorption patterns. Similar experiments using a conservative tracer also exhibit anomalous behavior. In parallel batch experiments, adsorption and desorption isotherms demonstrate hysteresis, indicating some permanent adsorption. While adsorption is described by the Langmuir isotherm, equilibrium concentrations are higher than those predicted by the same model for desorption. Furthermore, batch and flow-through column experiments show the occurrence of ion exchange of nickel with magnesium and potassium in the soil; aluminum and other ion concentrations are also affected by the presence of nickel. Strong retention of nickel during transport in soil columns leads to delayed initial breakthrough (~40 pore volumes), slow increase in concentration, and extended concentration tailing at long times. Standard models, including two-site non-equilibrium formulations, fail to capture these features quantitatively. We describe the mechanisms of transport and adsorption/desorption in terms of a continuous time random walk (CTRW) model, and use a particle tracking formulation to simulate the nickel migration in the column. This approach allows us to capture the non-Fickian transport and the subtle local effects of adsorption and desorption. The model uses transport parameters estimated from the conservative tracer and, as a starting point, adsorption/desorption parameters based on the batch experiments to account for the reactions. It is shown that the batch parameters under-estimate the actual adsorption in the column. The CTRW particle tracking model is shown to capture both the full evolution of the measured breakthrough curve and the measured spatial concentration profile. Analysis of these results provides further understanding of the interaction and dynamics between transport and sorption mechanisms in

  10. Computational Modeling and Experimental Studies on NO(x) Reduction Under Pulveerized Coal Combustion Conditions. Quarterly technical progress report, July 1 - September 30, 1997

    Kumpaty, S.K.; Subramanian, K.; Darboe, A.; Kumpati, S.K.


    Several experiments were conducted during this quarter to study the NO{sub x} reduction effectiveness of lignite coal, activated carbon and catalytic sites such as calcium sulfide and calcium carbide. While some of the coals/chemicals could be fed easily, some needed the mixing with silica gel to result in a uniform flow through the feeder. Several trial runs were performed to ensure proper feeding of the material before conducting the actual experiment to record NO{sub x} reduction. The experimental approach has been the same as presented in the past two quarterly reports with the coal reburning experiments. Partial reduction is achieved through methane addition for SR2=0.95 conditions and then coal or the catalyst is introduced to see if there is further reduction. Presented below are the results of the experiments conducted during this quarter.

  11. Influence of action of coal dust on metabolism of histamine and serotonin in the body (clinical and experimental study)

    Gridneva, N.V.; Dainega, V.G.; Talakin, Yu.N.


    Because of the role assigned to the destruction of the metabolism of biogenic amines in the pathogenesis of pneumoconiosis in miners and lack of information on metabolism of histamine and serotonin in first contact with coal dust, it was considered expedient to study peculiarities of their metabolism in the development of dust-induced lung pathology. A table shows results of a clinical study of the changes in the indicators of histamine and serotonin metabolism in miners with pneumoconiosis, those with a long period of service and a healthy control group. Miners with various forms of pneumoconiosis all show a significant increase in the histamine level of blood which may be related to the development in the presence of dust-induced lung disease of autoimmune processes accompanied by the liberation of free histamine from cells. With the increase in histamine, an increase of serotonin appears in blood of diseased miners. Long exposure to dust inflow activates metabolism of serotonin. In addition to the clinical study of diseased miners, an experimental investigation was made of the content of serotonin and histamine in organs of white rats. Table 2 shows that after introduction of coal dust over 1-4 months, the accumulation of serotonin in lungs, brain, kidneys, liver, and small intestine increased and the accumulation of histamine in liver, kidneys and brain decreased. Inhalation of dust produces a greater change in content of serotonin in organs; the intratracheal introduction of dust changes content of histamine. Results of experiment confirm destruction of metabolism of histamine and serotonin by coal/rock dust which proves need to use antiserotonins to cure lung disease. High content of histamine in blood determines need for use of antihistamine preparations especially in the presence of bronchospasms caused by effect of histamine on smooth muscle of bronchi.

  12. Experimental investigation of fluidised bed co-combustion of meat and bone meal with coals and olive bagasse

    L. Fryda; K. Panopoulos; P. Vourliotis; E. Pavlidou; E. Kakaras [National Technical University of Athens, Athens (Greece). Laboratory of Steam Boilers and Thermal Plants, School of Mechanical Engineering


    Meat and bone meal (MBM) were co-fired in a laboratory scale fluidised bed combustion (FBC) apparatus together with three different primary fuels: two coal types and olive bagasse residues. Several two component fuel blends were tested under different combustion conditions to study how primary fuel substitution by MBM affects flue gas emissions as well as fluidised bed (FB) agglomeration tendency. MBM, being a highly volatile fuel, caused significant increase of CO emissions and secondary air should be used in industrial scale applications to conform to regulations. The high N-content of MBM is moderately reflected on the increase of nitrogen oxides emissions, which are reduced by MBM derived volatiles. The MBM ash, although containing bone material rich in Ca, did not create any noteworthy desulphurisation effect. The observed slight decrease in SO{sub 2} emissions is predominantly attributed to the lower sulphur content in the coal/MBM fuel mixtures. The experimental work is evaluated with bed agglomeration indices from literature. The SEM/EDS analysis of bed material samples from the coal/MBM tests revealed the formation of conglomerates of bed material debris and ash with sizes that do not greatly exceed the original bed inventory and thus are not problematic. On the contrary, the co-combustion tests of olive bagasse residues with MBM led to a prompt loss of fluidisation, as a consequence of the high potassium and silicon content of the olive bagasse, the chlorine contents in both MBM and olive bagasse, and the high phosphorus content in the MBM also forming eutectics with potassium. 44 refs., 17 figs., 5 tabs.

  13. Analytical and Experimental Assessment of Seismic Vulnerability of Beam-Column Joints without Transverse Reinforcement in Concrete Buildings

    Hassan, Wael Mohammed

    Beam-column joints in concrete buildings are key components to ensure structural integrity of building performance under seismic loading. Earthquake reconnaissance has reported the substantial damage that can result from inadequate beam-column joints. In some cases, failure of older-type corner joints appears to have led to building collapse. Since the 1960s, many advances have been made to improve seismic performance of building components, including beam-column joints. New design and detailing approaches are expected to produce new construction that will perform satisfactorily during strong earthquake shaking. Much less attention has been focused on beam-column joints of older construction that may be seismically vulnerable. Concrete buildings constructed prior to developing details for ductility in the 1970s normally lack joint transverse reinforcement. The available literature concerning the performance of such joints is relatively limited, but concerns about performance exist. The current study aimed to improve understanding and assessment of seismic performance of unconfined exterior and corner beam-column joints in existing buildings. An extensive literature survey was performed, leading to development of a database of about a hundred tests. Study of the data enabled identification of the most important parameters and the effect of each parameter on the seismic performance. The available analytical models and guidelines for strength and deformability assessment of unconfined joints were surveyed and evaluated. In particular, The ASCE 41 existing building document proved to be substantially conservative in joint shear strength estimation. Upon identifying deficiencies in these models, two new joint shear strength models, a bond capacity model, and two axial capacity models designed and tailored specifically for unconfined beam-column joints were developed. The proposed models strongly correlated with previous test results. In the laboratory testing phase of

  14. 煤矸石煅烧实验研究%Coal Gangue Calcined Experimental Study



    This paper discusses the three major factors affecting coal gangue calcined whitening and structure changes before and after calcination,points out that the calcination process selection is the ket section,but the factors is associated,mutual penetration,should not be ignored.%论述了影响煤矸石煅烧增白的三大因素及煅烧前后的结构变化,指出煅烧工艺选择是关键,但各因素又是相关连、互相渗透的,都不应忽视。

  15. Co-firing Bosnian coals with woody biomass: Experimental studies on a laboratory-scale furnace and 110 MWe power unit

    Smajevic Izet


    Full Text Available This paper presents the findings of research into cofiring two Bosnian cola types, brown coal and lignite, with woody biomass, in this case spruce sawdust. The aim of the research was to find the optimal blend of coal and sawdust that may be substituted for 100% coal in large coal-fired power stations in Bosnia and Herzegovina. Two groups of experimental tests were performed in this study: laboratory testing of co-firing and trial runs on a large-scale plant based on the laboratory research results. A laboratory experiment was carried out in an electrically heated and entrained pulverized-fuel flow furnace. Coal-sawdust blends of 93:7% by weight and 80:20% by weight were tested. Co-firing trials were conducted over a range of the following process variables: process temperature, excess air ratio and air distribution. Neither of the two coal-sawdust blends used produced any significant ash-related problems provided the blend volume was 7% by weight sawdust and the process temperature did not exceed 1250ºC. It was observed that in addition to the nitrogen content in the co-fired blend, the volatile content and particle size distribution of the mixture also influenced the level of NOx emissions. The brown coal-sawdust blend generated a further reduction of SO2 due to the higher sulphur capture rate than for coal alone. Based on and following the laboratory research findings, a trial run was carried out in a large-scale utility - the Kakanj power station, Unit 5 (110 MWe, using two mixtures; one in which 5%/wt and one in which 7%/wt of brown coal was replaced with sawdust. Compared to a reference firing process with 100% coal, these co-firing trials produced a more intensive redistribution of the alkaline components in the slag in the melting chamber, with a consequential beneficial effect on the deposition of ash on the superheater surfaces of the boiler. The outcome of the tests confirms the feasibility of using 7%wt of sawdust in combination

  16. Experimental study on stability control technology of surrounding rock of deep roadways in coal mine

    Luo Yong; Yuan Liang; Yang Yang


    In order to solve effectively the problems of deep mining with safety and high efficiency,the multi-ple factors influencing the stability of deep rock roadway and technical problems are analyzed in the light of the severe situation of effective mining for deep coal resource,and the stability control methods for deep rock road-way are provided,which are based on the idea of combined support with separated steps and integral control of surrounding rock of deep rock roadway. The suggested methods were applied to a deep rock roadway with-648 m depth in Gubei coal mine of Huainan area. The field test was carried out and the in-situ monitoring was imple-mented,and the support scheme was optimized and adjusted to improve the stability of the surrounding rock of the roadway based on the feedback analysis. The results showed that the stability can be improved greatly by the provided control methods for deep roadway. The present methods for stability control of deep rock roadway can be used to other deep rock roadways with the similar conditions.

  17. Numerical and experimental study of strata behavior and land subsidence in an underground coal gasification project

    Sirdesai, N. N.; Singh, R.; Singh, T. N.; Ranjith, P. G.


    Underground Coal Gasification, with enhanced knowledge of hydrogeological, geomechanical and environmental aspects, can be an alternative technique to exploit the existing unmineable reserves of coal. During the gasification process, petro-physical and geomechanical properties undergo a drastic change due to heating to elevated temperatures. These changes, caused due to the thermal anisotropy of various minerals, result in the generation of thermal stresses; thereby developing new fracture pattern. These fractures cause the overhead rock strata to cave and fill the gasification chamber thereby causing subsidence. The degree of subsidence, change in fluid transport and geomechanical properties of the rock strata, in and around the subsidence zone, can affect the groundwater flow. This study aims to predict the thermo-geomechanical response of the strata during UCG. Petro-physical and geomechanical properties are incorporated in the numerical modelling software COMSOL Multiphysics and an analytical strength model is developed to validate and further study the mechanical response and heat conduction of the host rock around the gasification chamber. Once the problems are investigated and solved, the enhanced efficiency and the economic exploitation of gasification process would help meet country's energy demand.

  18. Experimental research on inorganic solidified foam for sealing air leakage in coal mines

    Bo tao Qin; Yi Lu


    In order to efficiently seal air leakages and control spontaneous combustion of coal,solidified foam was developed by adding a certain compound additive to fly coal ash and cement as the main materials.It was prepared basing on the foaming characteristic through physical and mechanical system.We studied the effects of the different types of foaming agents,the mass ratio of cement to fly ash,and the mass ratio of solid to water and content of cellulose on the performance of solidified foam.The results show that when adding the composite protein,surfactant and cellulose foaming agents.The cement-fly ash ratio of 0.75:1,the water solid ratio as large as 2:1,and the solidified foam with high properties and density of only 516 kg/m3 and compressive strength of up to 12.68 MPa were prepared.But the initial setting time,identity and compressive strength may be changed by varying the water solid ratio and/or the additives.We theoretically analyzed the influence mechanism of foam density,compressive strength and water solid ratio.The solidified foam is especially suitable for sealing surface leakage channels and filling the goaf with a wide application prospects.

  19. [Experimental study on the size spectra and emission factor of ultrafine particle from coal combustion].

    Sun, Zai; Yang, Wen-jun; Xie, Xiao-fang; Chen, Qiu-fang; Cai, Zhi-liang


    The emission characteristics of ultrafine particles released from pulverized coal combustion were studied, the size spectra of ultrafine particles (5.6-560 nm) were measured with FMPS (fast mobility particle sizer) on a self-built aerosol experiment platform. Meanwhile, a particle dynamic evolution model was established to obtain the particle deposition rate and the emission rate through the optimized algorithm. Finally, the emission factor was calculated. The results showed that at the beginning of particle generation, the size spectra were polydisperse and complex, the initial size spectra was mainly composed of three modes including 10 nm, 30-40 nm and 100-200 nm. Among them, the number concentration of mode around 10 nm was higher than those of other modes, the size spectrum of around 100-200 nm was lognormal distributed, with a CMD (count median diameter) of around 16 nm. Then, as time went on, the total number concentration was decayed by exponential law, the CMD first increased and then tended to be stable gradually. The calculation results showed that the emission factor of particles from coal combustion under laboratory condition was (5.54 x 10(12) ± 2.18 x 10(12)) unit x g(-1).

  20. Experimental studies on the group ignition of a cloud of coal particles: Volume 2, Pyrolysis and ignition modeling

    Annamalai, K.; Ryan, W.


    The primary objectives of this work are to formulate a model to simulate transient coal pyrolysis, ignition, and combustion of a cloud of coal particles and to compare results of the program with those reported in the literature elsewhere.

  1. Beneficiated coals' char morphology

    Diana Vargas


    Full Text Available This work evaluated the char morphology of beneficiated and original coal (without beneficiation from four Colombian coalmines: Cerrejón (La Guajira, La Jagua (Cesar, Guachinte (Valle del Cauca and Nechí (Antioquia. Column flotation was used to obtain beneficiated coal, whereas a drop tube reactor at 1,000°C, 104 °C/s heating rate and 100 ms residence time was used to obtain char. The chars were analysed by image analysis which determined their shape, size, porosity and wall thickness. It was found that char morphology depended on coal rank and maceral composition. Morphological characteristics like high porosity, thinner walls and network-like morphology which are beneficial in improving combustion were present in vitrinite- and liptinite-rich lowest-ranking coals. Beneficiated coals showed that their chars had better performance regarding their morphological characteristics than their original coal chars.

  2. Improving the performance of conventional and column froth flotation cells

    Arnold, B.J. [CQ Inc., Homer City, PA (United States)


    Many existing mining operations hover on the brink of producing competitively priced fuel with marginally acceptable sulfur levels. To remain competitive, these operations need to improve the yield of their coal processing facilities, lower the sulfur content of their clean coal, or lower the ash content of their clean coal. Fine coal cleaning processes offer the best opportunity for coal producers to increase their yield of high quality product. Over 200 coal processing plants in the U.S. already employ some type of conventional or column flotation device to clean fines. an increase in efficiency in these existing circuits could be the margin required to make these coal producers competitive.

  3. CFD simulation and experimental investigation of the copper solvent extraction in a pilot plant pulsed packed column in Sarcheshmeh Copper Complex

    Mirzaie, Maryam; Sarrafi, Amir; Hashemipour, Hasan; Baghaie, Ali; Molaeinasab, Mehdi


    Present work deals with the development of a computational fluid dynamics (CFD) model for investigate the extraction of copper from leach solution with the Lix84-I. The model is based on Eulerian-Eulerian two phase equations in conjunction with the realizable k-ɛ model for turbulence. Population balance modeling (PBM) is used to describe the dynamics of the time and space variation of droplet sizes in the column. The PBM equation is solved using the class method. The mass transfer is the important parameters which can improve the performance of pulsed column and changes widely with the variation in the droplet number density. Valid empirical correlations were implemented to the CFD model for mass transfer coefficients by user defined functions. To validate the model, the results of CFD model and experimental measurements were compared and there was a good agreement between them. The effects of flow rates and intensity of pulsation on the yield of copper extraction and entrainment of the organic phase were studied. The results shown that increasing the phase ratio (the flow rate of organic phase/aqueous phase) from 0.5 to 1.75, caused yield of copper extraction from leach solution increased from 31 to 91%. The organic entrainment increased with increasing the pulse intensity and phase flow rates. Additionally, the results show that the performance of the pulsed packed column for copper extraction is reasonable.

  4. Measurement method and experimental research on flame emissivity in Coal-fired furnaces

    YANG Chao; LOU Chun; JIANG Zhi-wei; ZHOU Huai-chun


    The combustion condition in coal-fired furnaces of the large power station boiler is very complex and the flame emissivity is one of the important combustion parameters.A measurement method of the flame emissivity based on the blackbody furnace calibration of CCD(Charge Coupled Device)cameras and the color image processing techniques of computer was introduced.The experimentaI research on the flame emissivity in a 200 MW boiler furnace and a 300 MW boiler furnace was conducted respectively through the several CCD cameras installed at different height in furnace.The measurement results show:the flame emissivity increases with the increase of the unit load.the flame emissivity of the burner areas in furnace is the highest and the flame emissivity decrease with the increase of height of furnace above the burners area.

  5. Experimental research on behavior of 460 MPa high strength steel I-section columns under cyclic loading

    Wang, Jiaojiao; Shi, Gang; Shi, Yongjiu


    To investigate the seismic behavior of I-section columns made of 460 MPa high strength steel (HSS), six specimens were tested under constant axial load and cyclic horizontal load. The specimens were designed with different width-to-thickness ratios and loaded under different axial load ratios. For each specimen, the failure mode was observed and hysteretic curve was measured. Comparison of different specimens on hysteretic characteristic, energy dissipation capacity and deformation capacity were further investigated. Test results showed that the degradation of bearing capacity was due to local buckling of flange and web. Under the same axial load ratio, as width-to-thickness ratio increased, the deformation area of local buckling became smaller. And also, displacement level at both peak load and failure load became smaller. In addition, the full extent of hysteretic curve, energy dissipation capacity, ultimate story drift angle decreased, and capacity degradation occurred more rapidly with the increase of width-to-thickness ratio or axial load ratio. Based on the capacity of story drift angle, limiting values which shall not be exceeded are suggested respectively for flange and web plate of 460 MPa HSS I-section columns when used in SMFs and in IMFs in the case of axial load ratio no more than 0.2. Such values should be smaller when the axial load ratio increases.

  6. Experimental study of impact-cratering damage on brittle cylindrical column model as a fundamental component of space architecture

    Fujiwara, Akira; Onose, Naomi; Setoh, Masato; Nakamura, Akiko M.; Hiraoka, Kensuke; Hasegawa, Sunao; Okudaira, Kyoko


    The cylindrical column of brittle material processed from soil and rock is a fundamental component of architectures on the surface of solid bodies in the solar system. One of the most hazardous events for the structure is damaging by hypervelocity impacts by meteoroids and debris. In such a background, cylindrical columns made of plaster of Paris and glass-bead-sintered ceramic were impacted by spherical projectiles of nylon, glass, and steel at velocity of about 1-4.5 km/s. Measured crater radii, depth, and excavated mass expressed by a function of the cylinder radius are similar irrespective of the target material, if those parameters are normalized by appropriate parameters of the crater produced on the flat-surface target. The empirical scaling relations of the normalized crater radii and depth are provided. Using them, crater dimensions and excavated mass of crater on cylindrical surface of any radius can be predicted from the existing knowledge of those for flat surface. Recommendation for the minimum diameter of a cylinder so as to resist against a given impact is provided.

  7. Experimental and numerical validation of the effective medium theory for the B-term band broadening in 1st and 2nd generation monolithic silica columns.

    Deridder, Sander; Vanmessen, Alison; Nakanishi, Kazuki; Desmet, Gert; Cabooter, Deirdre


    Effective medium theory (EMT) expressions for the B-term band broadening in monolithic silica columns are presented at the whole-column as well as at the mesoporous skeleton level. Given the bi-continuous nature of the monolithic medium, regular as well as inverse formulations of the EMT-expressions have been established. The established expressions were validated by applying them to a set of experimental effective diffusion (Deff)-data obtained via peak parking on a number of 1st and 2nd generation monolithic silica columns, as well as to a set of numerical diffusion simulations in a simplified monolithic column representation (tetrahedral skeleton model) with different external porosities and internal diffusion coefficients. The numerically simulated diffusion data can be very closely represented over a very broad range of zone retention factors (up to k″=80) using the established EMT-expressions, especially when using the inverse variant. The expressions also allow representing the experimentally measured effective diffusion data very closely. The measured Deff/Dmol-values were found to decrease significantly with increasing retention factor, in general going from about Deff/Dmol=0.55 to 0.65 at low k″ (k″≅1.5-3.8) to Deff/Dmol=0.25 at very high k″ (k″≅40-80). These values are significantly larger than observed in fully-porous and core-shell particles. The intra-skeleton diffusion coefficient (Dpz) was typically found to be of the order of Dpz/Dmol=0.4, compared to Dpz/Dmol=0.2-0.35 observed in most particle-based columns. These higher Dpz/Dmol values are the cause of the higher Deff/Dmol values observed. In addition, it also appears that the higher internal diffusion is linked to the higher porosity of the mesoporous skeleton that has a relatively open structure with relatively wide pores. The observed (weak) relation between Dpz/Dmol and the zone retention factor appears to be in good agreement with that predicted when applying the regular

  8. Cromatografando em coluna com resina de almécega: um projeto para química orgânica experimental Column chromatography with almécega resin: a project for experimental organic chemistry

    Gerardo Magela Vieira Júnior


    Full Text Available The use of natural products to demonstrate the silica gel column chromatography technique is proposed in the present article. It describes the separation of the triterpenes alpha- and beta-amirin from the diol breine and maniladiol, obtained from almécega resin (Protium heptaphyllum March.. The experiment uses an accessible material, was accomplished in 4 h, and can be applied with success an the experimental course of organic chemistry for undergraduate students.

  9. Experimental Study On Lateral Load Capacity of Bamboo RC Beam Column Joints Strengthened By Bamboo Mechanical Anchors

    Sri Umniati B.


    Full Text Available In this paper, the prospective of bamboos which available abundantly especially in Indonesia as rebars and mechanical anchors are studied. And also the endurance of the bamboos mechanical anchors to withstand cyclic loading were observed. Nine classes of bamboos bar were evaluated: consist of 3 different anchors (0, 4 and 8 anchors and 3 different compressive strength (19.19 MPa, 29.61 MPa and 37.96 MPa means 3 × 3 parameters. The results show that the lateral load capacity increased significantly with the present of bamboo anchors specimens: 26.04 % for 4 anchors specimens (C2 and 25 % for the 8 anchors specimens (C3 compared to zero anchor specimens (C1. On the other hand, the compressive strength of concrete have no significant effects to the lateral load capacity. Overall it can be concluded that, bamboo can be used as mechanical anchorage to strengthen beam column joint.

  10. Defluoridation of drinking water using a new flow column-electrocoagulation reactor (FCER) - Experimental, statistical, and economic approach.

    Hashim, Khalid S; Shaw, Andy; Al Khaddar, Rafid; Ortoneda Pedrola, Montserrat; Phipps, David


    A new batch, flow column electrocoagulation reactor (FCER) that utilises a perforated plate flow column as a mixer has been used to remove fluoride from drinking water. A comprehensive study has been carried out to assess its performance. The efficiency of fluoride removal (R%) as a function of key operational parameters such as initial pH, detention time (t), current density (CD), inter-electrode distance (ID) and initial concentration (C0) has been examined and an empirical model has been developed. A scanning electron microscopy (SEM) investigation of the influence of the EC process on morphology of the surface of the aluminium electrodes, showed the erosion caused by aluminium loss. A preliminary estimation of the reactor's operating cost is suggested, allowing for the energy from recycling of hydrogen gas hydrogen gas produced amount. The results obtained showed that 98% of fluoride was removed within 25 min of electrolysis at pH of 6, ID of 5 mm, and CD of 2 mA/cm(2). The general relationship between fluoride removal and operating parameters could be described by a linear model with R(2) of 0.823. The contribution of the operating parameters to the suggested model followed the order: t > CD > C0 > ID > pH. The SEM images obtained showed that, after the EC process, the surface of the anodes, became non-uniform with a large number of irregularities due to the generation of aluminium hydroxides. It is suggested that these do not materially affect the performance. A provisional estimate of the operating cost was 0.379 US $/m(3). Additionally, it has been found that 0.6 kW/m(3) is potentially recoverable from the H2 gas. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  11. Hydrotreating of coal-derived liquids

    Lott, S.E.; Stohl, F.V.; Diegert, K.V. [Sandia National Lab., Albuquerque, NM (United States)] [and others


    To develop a database relating hydrotreating parameters to feed and product quality by experimentally evaluating options for hydrotreating whole coal liquids, distillate cuts of coal liquids, petroleum, and blends of coal liquids with petroleum.

  12. Column chromatographic separation of polycyclic aromatic hydrocarbons in coal tar pitch and its GC/MS analysis%煤焦油沥青中多环芳烃的柱层析分离及其GC—MS分析

    罗道成; 刘俊峰


    Coal tar pitch was extracted with isometric carbon disulfide - acetone mixed solvent under ultrasonic radiation and room temperature. Polycyclic aromatic hydrocarbons (PAHs) in coal tar pitch were extracted by mixed solvent. The extracts were absorbed by silica gel. The silica gel was eluted with petroleum ether, PAHs in coal tar pitch were separated by using column chromatographic method. A white crystal, a white powder and a colorless crystal (marked as M1, M2, M3 respectively) appeared in three eluents, and M1 ,M2 and M3 were analyzed with GC -MS respectively. The results showed that M1 was mainly composed of 3 - ring PAHs and heterocyclic compounds, M2 was mainly composed of 4 - ring PAHs and heterocyclic compounds, and Ms was composed of 4 - ring or 5 - ring PAHs.%室温下用等体积的二硫化碳-丙酮混合溶剂对煤焦油沥青进行超声辐射萃取,煤焦油沥青中多环芳烃(PAHs)被混合溶剂萃取,用硅胶吸附萃取物,以石油醚为洗脱液洗脱硅胶,采用柱层析法对煤焦油沥青中多环芳烃进行了分离.在定量收取的洗脱液中分别析出了白色晶体、白色粉状物质和无色晶体(分别标记为M1,M2,M3),用气相色谱-质谱联用仪(GC/MS)分别对M1,M2,M3进行了分析,结果表明,M1中主要为3个环的多环芳烃和杂环化合物,M2中主要为4个环的多环芳烃和杂环化合物,M3中全部为4~5个环的多环芳烃.

  13. Experimental Study on Low-Strength Similar-Material Proportioning and Properties for Coal Mining

    Shaojie Chen


    Full Text Available Similar-material simulation test is an effective tool to study the practical problems in mining and civil engineering. This paper conducts an orthogonal study on low-strength similar materials comprising sand, fly ash, and plaster and analyses the sensitivity of the materials. The mechanical properties of the similar materials strongly depend on the proportioning ratio, and they can satisfy different similar-material simulation tests. The compression strength and elastic modulus of the similar material decrease as the sand-binder ratio or cement ratio increases. There are approximately linear relations between the compression strength/elastic modulus and sand-binder ratio and approximately power relations between the compression strength/elastic modulus and sand-binder ratio. Sensitivity analysis employing the range method shows that the effects of the cement ratio on the compression strength and elastic modulus are more obvious than the effects of the sand-binder ratio. Finally, one of similar materials is used in a simulation test of coal backfill mining.

  14. Gas/slurry flow in coal-liquefaction processes (fluid dynamics in a three-phase-flow column). Final technical progress report, 1 October 1979-31 March 1982

    Ying, D.H.S.; Sivasubramanian, R.; Moujaes, S.F.; Givens, E.N.


    A commercial coal liquefaction plant will employ vertical tubular reactors feeding slurry and gas concurrently upward through these vessels. In the SRC-I plant design the reactor is essentially an empty vessel with only a distributor plate located near the inlet. Because the commercial plant represents a considerable scale-up over Wilsonville or any pilot plant, this program addressed the need for additional data on behavior of three phase systems in large vessels. Parameters that were investigated in this program were studied at conditions that relate directly to projected plant operating conditions. The fluid dynamic behavior of the three-phase upflow system was studied by measuring gas and slurry holdup, liquid dispersion, solids suspension and solids accumulation. The dependent parameters are gas and liquid velocities, solid particle size, solids concentration, liquid viscosity, liquid surface tension and inlet distributor. Within the range of liquid superficial velocity from 0.0 to 0.5 ft/sec, gas holdup is found to be independent of liquid flow which agrees with other investigators. The results also confirm our previous finding that gas holdup is independent of column diameter when the column diameter is 5 inches or larger. The gas holdup depends strongly on gas flow rate; gas holdup increases with increasing gas velocity. The effect of solids particles on gas holdup depends on the gas flow rate. Increasing liquid viscosity and surface tension reduce gas holdup which agrees with other investigators. Because of the complexity of the system, we could not find a single correlation to best fit all the data. The degree of liquid backmixing markedly affects chemical changes occurring in the dissolver, such as sulfur removal, and oil and distillate formation.

  15. Experimental investigation on the infrared refraction and extinction properties of rock dust in tunneling face of coal mine.

    Wang, Wenzheng; Wang, Yanming; Shi, Guoqing


    Comprehensive experimental research on the fundamental optical properties of dust pollution in a coal mine is presented. Rock dust generated in a tunneling roadway was sampled and the spectral complex refractive index within an infrared range of 2.5-25 μm was obtained by Fourier transform infrared spectroscopy measurement and Kramers-Kronig relation. Experimental results were validated to be consistent with equivalent optical constants simulated by effective medium theory based on component analysis of x-ray fluorescence, which illustrates that the top three mineral components are SiO2 (62.06%), Al2O3 (21.26%), and Fe2O3 (4.27%). The complex refractive index and the spatial distribution tested by a filter dust and particle size analyzer were involved in the simulation of extinction properties of rock dust along the tunneling roadway solved by the discrete ordinates method and Mie scattering model. The compared results illustrate that transmission is obviously enhanced with the increase of height from the floor but weakened with increasing horizontal distance from the air duct.

  16. Full factorial experimental design analysis of Rhodamine B removal from water using organozeolite from coal bottom ash

    Raquel R. Alcântara, Rafael O. R. Muniz, Denise A. Fungaro


    Full Text Available Zeolitic material synthesized using coal bottom ash asraw materialwas modified by cationic surfactant. Raw bottom ash and zeolitic materials were characterized using various techniques to obtain its physical and chemical properties. Surfactant modified zeolite (SMZBA was used as alternative low-cost adsorbent for removal of Rhodamine B (RB dye from aqueous solution. Dye adsorption equilibrium was attained after 40 min of the contact time and adsorption kinetics were described by the pseudo second order kinetic model. Equilibrium adsorption data were adjusted using non-linear equations of the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R models. Error analysis showed that D-R was the most appropriate for fitting the experimental data.The reuse of the remaining solution generated from the synthesis of zeolite was effective. To optimize the operating conditions, the temperature, pH, adsorbent dosage and initial concentration of the dye were investigated by full factorial experimental design method; adsorbent dosage, initial concentration and interaction of the two were found as the most significant factors with P = 0.02 lower than 95% confidence level. The results showed that SMZBA is a good adsorbent for the removal of RB from aqueous effluent.

  17. PAHs and organic matter partitioning and mass transfer from coal tar particles to water.

    Benhabib, Karim; Simonnot, Marie-Odile; Sardin, Michel


    The coal tar found in contaminated soils of former manufactured gas plants and coking plants acts as a long-term source of PAHs. Organic carbon and PAH transfer from coal tar particles to water was investigated with closed-looped laboratory column experiments run at various particle sizes and temperatures. Two models were derived. The first one represented the extraction process at equilibrium and was based on a linear partitioning of TOC and PAHs between coal tar and water. The partition coefficient was derived as well as the mass of extractable organic matter in the particles. The second model dealt with mass transfer. Particle diffusion was the limiting step; organic matter diffusivity in the coal tar was then computed in the different conditions. A good consistency was obtained between experimental and computed results. Hence, the modeling of PAH migration in contaminated soils at the field scale requires taking into account coal tar as the source-term for PAH release.

  18. Reading Columns

    Coutts, Marion


    Reading Columns are twin permanent public sculptures commissioned as part of a £245m scheme for the redevelopment of the Chatham Place area in Reading. Dimensions: 3.5m high x 1.3m diameter each Field of knowledge: The work consists of twin bespoke columns of stainless steel and glass over digital colour transparencies. The piece revisits and reworks the idea of the Morris Column, a 19th C feature characteristic of major European metropolitan centres. A wraparound image on each of ...

  19. 应用隔壁式精馏塔分离煤制烯烃设计%Design of Separation Process with Dividing-Wall Column for Light Olefins Based Coal

    李俊龙; 陈超; 倪欣怡; 王丹丹; 孙强; 郭绪强


    利用 Aspen HYSYS 流程模拟软件完成隔壁式精馏塔的设计,设计过程中引用逻辑操作单元将隔壁式精馏塔的预分离塔与主精馏塔进行了耦合,逻辑操作单元的引入可以减少隔壁式精馏塔的自由度,从而降低了精馏塔模拟达到稳态时的难度。在完成精馏塔设计并得到结果的基础上,对稳态工艺过程模拟结果进行灵敏度分析,考察了隔壁式精馏塔侧线抽出流量、回流比、进料温度、气相回流流量和液相回流流量对隔壁式精馏塔塔顶、中间以及塔底组成的影响,得到优化后的工艺操作参数。同时根据隔壁式精馏塔分离产物的组成提出并联分离顺序,与原有的顺序分离相比流程更加紧凑,对实际的烯烃分离流程的设计工作具有参考意义。%A design about application of dividing-wall to separate light olefins based coal was accomplished in software Aspen HYSYS.The logic recycle operation units coupled the pre-fractionator with main fractionator,which could reduce the number of column freedom.The sensitivity analyses were made on the base of stable process design,which included the relationship between middle stream mole flow rate drown out of main column,reflex ratio,feed stream temperature,vapor mole flow rate recycle back to pre-fractionator,liquid recycle back to pre-fractionator and main column top,middle and bottom composition, then optimized operation parameters were obtained.And a novel separation process was addressed according to the mole fraction of three production stream,which was more compact than traditional separation process.

  20. Simulation Optimization and Experimental Study of Cross-Wall Adiabatic Dividing Wall Column Used to Separate Hexane-Heptane-Octane System

    Hu Yuqi; Fang Jing; Li Chunli


    Through separation of the hexane-heptane–octane system in a cross-wall adiabatic dividing wall column, the ef-fects of feed position, side-draw position, liquid split ratio, vapor split ratio and their interactions on the energy consumption were analyzed by Aspen Plus under the constant product purity, and the response surface model for the energy consumption was regressed. Based on the restriction on the optimal operating zone, the comparison of different combinations of surrogate models and optimization methods showed that, the combination of the Kriging model and multi-island genetic algorithm (Kriging-MIGA) had better prediction ability than the combination of the response surface model and partial derivative method (RSM-PD), and RSM-PD had better optimization effect than Kriging-MIGA. With a self-made cross-wall adiabatic dividing wall column, the temperature at measuring points and the energy consumption were measured during experiments, the comparison between measured values and simulated ones demonstrated that the optimized values of variables searched by RSM-PD and Kriging-MIGA could be both used as the optimum technological conditions since the experimental reli-ability was ensured, with the optimum technological conditions shown below: The feed position is 6, the side-draw position is 7, the combinations of liquid split ratio and vapor split ratio are [0.14, 0.5] and [0.16, 0.52], respectively. RSM-PD and Kriging-MIGA can provide the appropriate optimization methods for the dividing wall column.

  1. Energy efficient electrocoagulation using a new flow column reactor to remove nitrate from drinking water - Experimental, statistical, and economic approach.

    Hashim, Khalid S; Shaw, Andy; Al Khaddar, Rafid; Pedrola, Montserrat Ortoneda; Phipps, David


    In this investigation, a new bench-scale electrocoagulation reactor (FCER) has been applied for drinking water denitrification. FCER utilises the concepts of flow column to mix and aerate the water. The water being treated flows through the perforated aluminium disks electrodes, thereby efficiently mixing and aerating the water. As a result, FCER reduces the need for external stirring and aerating devices, which until now have been widely used in the electrocoagulation reactors. Therefore, FCER could be a promising cost-effective alternative to the traditional lab-scale EC reactors. A comprehensive study has been commenced to investigate the performance of the new reactor. This includes the application of FCER to remove nitrate from drinking water. Estimation of the produced amount of H2 gas and the yieldable energy from it, an estimation of its preliminary operating cost, and a SEM (scanning electron microscope) investigation of the influence of the EC process on the morphology of the surface of electrodes. Additionally, an empirical model was developed to reproduce the nitrate removal performance of the FCER. The results obtained indicated that the FCER reduced the nitrate concentration from 100 to 15 mg/L (World Health Organization limitations for infants) after 55 min of electrolysing at initial pH of 7, GBE of 5 mm, CD of 2 mA/cm(2), and at operating cost of 0.455 US $/m(3). Additionally, it was found that FCER emits H2 gas enough to generate a power of 1.36 kW/m(3). Statistically, the relationship between the operating parameters and nitrate removal could be modelled with R(2) of 0.848. The obtained SEM images showed a large number dents on anode's surface due to the production of aluminium hydroxides.

  2. Coal char fragmentation during pulverized coal combustion

    Baxter, L.L.


    A series of investigations of coal and char fragmentation during pulverized coal combustion is reported for a suite of coals ranging in rank from lignite to low-volatile (lv) bituminous coal under combustion conditions similar to those found in commercial-scale boilers. Experimental measurements are described that utilize identical particle sizing characteristics to determine initial and final size distributions. Mechanistic interpretation of the data suggest that coal fragmentation is an insignificant event and that char fragmentation is controlled by char structure. Chars forming cenospheres fragment more extensively than solid chars. Among the chars that fragment, large particles produce more fine material than small particles. In all cases, coal and char fragmentation are seen to be sufficiently minor as to be relatively insignificant factors influencing fly ash size distribution, particle loading, and char burnout.

  3. Synthesis of zeolites coal ash in surfactant modified in application and removal of orange 8 acid solution: study in batch, fixed bed column and evaluation ecotoxicological; Sintese de zeolitas de cinzas de carvao modificada por surfactante e aplicacao na remocao de acido laranja 8 de solucao aquosa: estudo em leito movel, coluna de leito fixo e avaliacao ecotoxicologica

    Magdalena, Carina Pitwak


    In this study, synthesized zeolitic material from coal ash and modified cationic surfactant was used for removing the acid dye Orange 8 (AL8) by adsorption process using moving bed and fixed-bed column. The raw material and adsorbents were characterized by different techniques, such as X-ray diffraction, X-ray fluorescence spectroscopy, among others. The adsorption of AL8 was performed by moving bed in order to optimize the results when they are launched in a fixed bed. The effects of adsorption on zeolite AL8 were compared: (1) Effect of counterions Br{sup -} and Cl{sup -} surfactant used in the modification of the zeolite; (2) effect of type of coal ash used as raw material in the synthesis of zeolites (fly and bottom). The following adsorbents were used in the study: fly and bottom zeolite modified by surfactant hexadecyltrimethylammonium bromide (ZLMS-Br-Br and ZPMS-Br) and fly zeolite modified by surfactant hexadecyltrimethylammonium chloride (ZLMS-Cl). The pseudo-second-order kinetic described the adsorption of the dye on all adsorbents. The equilibrium time was reached 40, 60 and 120 min for ZLMS-Br, ZLMS-Cl and ZPMS-Br, respectively. The adsorption equilibrium was analyzed by the equations of the models of linear and nonlinear isotherms of Langmuir, Freundlich, Temkin and Dubinin- Radushkevivh (DR) and the criterion of best fit was evaluated using the error functions.The DR model was adjusted better to the experimental data for the system AL8 / ZLMS-Br, the Freundlich model for AL8 / ZLMS-Cl and Langmuir for AL8 / ZPMS. According to the Langmuir maximum adsorption capacity was 4.67, 1.48 and 1.38 mg g{sup -1} for ZLMS-Br, ZLMS-Cl and ZPMS-Br, in order. In studies employing fixed bed columns, the effects of inlet concentration (20- 30 mg L{sup -1}), flow rate (4.0 -5.3 mL min{sup -1}) and the bed height (5, 5 - 6.5 cm) above the breakthrough curves characteristics in the adsorption system were determined. The Adams-Bohart, Thomas, Yoon-Nelson models were

  4. Ultrasonic coal-wash for de-ashing and de-sulfurization. Experimental investigation and mechanistic modeling

    Ambedkar, B. [Indian Institute of Technology Madras, Chennai (India). Dept. of Chemical Engineering


    This study focuses on the physical aspects of ultrasonic de-ashing and de-sulfurization, such as cavitation, streaming and their combined effects. Ambedkar Balraj proposes an ultrasound-assisted coal particle breakage mechanism and explores aqueous and solvent-based ultrasonic techniques for de-ashing and de-sulfurization. Ambedkar designs a Taguchi L-27 fractional-factorial matrix to assess the individual effects of key process variables. In this volume he also describes process optimization and scale-up strategies. The author provides a mechanism-based model for ultrasonic reagent-based coal de-sulfurization, proposes a flow diagram for ultrasonic methods of high-throughput coal-wash and discusses the benefits of ultrasonic coal-wash. Coal will continue to be a major fuel source for the foreseeable future and this study helps improve its use by minimising ash and sulfur impurities.

  5. Experimental Study of the Influence of the Concentration of Organic Water-Coal Fuel Components on the Integral Ignition Characteristics

    Vershinina, K. Yu.; Kuznetsov, G. V.; Strizhak, P. A.


    To enlarge the power raw material base, the processes of stable initiation of combustion of drops of organic watercoal fuels have been investigated. For the main components, we used filter cakes (coal processing waste), anthracite, bituminous and brown coals of brands D and B2, water, and spent machine, turbine, and transformer oils. We have established the influence of concentrations of components on the minimum (limiting) ignition temperatures of organic water-coal fuels and the ignition delay times of drops of fuel components with initial sizes of 0.25-1.5 mm. Investigations were carried out for oxidizer temperatures of 600-1100 K and its velocities of 0.5-5 m/s characteristic of units, aggregates, and large and small power plants. We have determined the characteristic differences of organic water-coal fuel from water-coal fuel and the close laws of the investigated processes for these fuels.

  6. A comparison study of commercially-available column flotation technologies

    Honaker, R.Q.; Mohanty, M.K.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering; Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)


    A direct comparison of three commercially-available column flotation technologies, i.e., Jameson Cell, Microcel, and Packed-Column, has been conducted using a {minus}100 mesh Illinois No. 5 flotation feed coal sample. The separation performance of each flotation technology was optimized and their performance levels compared on the basis of both ash rejection, sulfur rejection, and throughput capacities. A parametric study using a statistically-designed experimental program was conducted to optimize the critical operating parameter values of each column. The ultimate performance curves for each column were generated by conducting additional tests using the optimized operating parameter values. The throughput capacity of each flotation cell was determined by conducting tests over a range of feed rates at the maximum superficial gas rate while maintaining the other parameters at their optimum values. The separation performance achieved by each of the three flotation cells was found to be comparable to the idealistic flotation performance predicted by release analysis. However, the fraction of wash water reporting to tailings (bias factor) was found to be critical in achieving the near idealistic performance. The bias factor required for the Packed-Column was found to be less than that required by the other two flotation cells. The sulfur rejection achieved by the Microcel and the Packed-Column were found to be greater than that achieved by the Jameson Cell and all three produced sulfur rejections exceeding the values obtained from release analysis. The throughput capacity, on the other hand, differed among the three flotation columns. The Jameson Cell and the Microcel were found to have comparable throughput capacities while the Packed-Column was found to have a lower capacity.

  7. Experimental Study of Kinetic Properties of Pyrolysis for Conveyor Belt in Coal Mine

    SONG Zheng-chang


    The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire.

  8. Calculation procedure to determine average mass transfer coefficients in packed columns from experimental data for ammonia-water absorption refrigeration systems

    Sieres, Jaime; Fernandez-Seara, Jose [University of Vigo, Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, Vigo (Spain)


    The ammonia purification process is critical in ammonia-water absorption refrigeration systems. In this paper, a detailed and a simplified analytical model are presented to characterize the performance of the ammonia rectification process in packed columns. The detailed model is based on mass and energy balances and simultaneous heat and mass transfer equations. The simplified model is derived and compared with the detailed model. The range of applicability of the simplified model is determined. A calculation procedure based on the simplified model is developed to determine the volumetric mass transfer coefficients in the vapour phase from experimental data. Finally, the proposed model and other simple calculation methods found in the general literature are compared. (orig.)

  9. Experimental Study on Anisotropic Strength and Deformation Behavior of a Coal Measure Shale under Room Dried and Water Saturated Conditions

    Jingyi Cheng


    Full Text Available This paper presents an experimental investigation of anisotropic strength and deformation behavior of coal measure shale. The effect of two factors (i.e., anisotropy and water content on shale strength and deformation behavior was studied. A series of uniaxial and triaxial compression tests were conducted on both room dried and water saturated samples for different lamination angles. The test results indicate that (1 the compressive strength, cohesion, internal friction angle, tangent Young’s modulus, and axial strain corresponding to the peak and residual strengths of room dried specimens exhibit anisotropic behavior that strongly depends on the orientation angle (β; (2 in comparison to the room dried samples, the compressive strength and Young’s modulus as well as the anisotropy are all reduced for water saturated specimens; and (3 the failure mechanism of the samples can be summarized into two categories: sliding along lamination and shearing of rock material, with the type occurring in a particular situation depending strongly on the lamination orientation angles with respect to the major principal stress. According to the findings, it is strongly recommended that the effect of anisotropy and water content on the strength and deformation behavior of the rock must be considered in ground control designs.


    Grimmett, E.S.


    This patent covers a continuous countercurrent liquidsolids contactor column having a number of contactor states each comprising a perforated plate, a layer of balls, and a downcomer tube; a liquid-pulsing piston; and a solids discharger formed of a conical section at the bottom of the column, and a tubular extension on the lowest downcomer terminating in the conical section. Between the conical section and the downcomer extension is formed a small annular opening, through which solids fall coming through the perforated plate of the lowest contactor stage. This annular opening is small enough that the pressure drop thereacross is greater than the pressure drop upward through the lowest contactor stage. (AEC)

  11. Experimental Investigation into the Combustion Characteristics on the Co-firing of Biomass with Coal as a Function of Particle Size and Blending Ratio

    Lkhagvadorj, Sh; Kim, Sang In; Lim, Ho; Kim, Seung Mo; Jeon, Chung Hwan [Pusan National Univ., Busan (Korea, Republic of); Lee, Byoung Hwa [Doosan Heavy Industries and Construction, Ltd., Changwon (Korea, Republic of)


    Co-firing of biomass with coal is a promising combustion technology in a coal-fired power plant. However, it still requires verifications to apply co-firing in an actual boiler. In this study, data from the Thermogravimetric analyzer(TGA) and Drop tube furnace(DTF) were used to obtain the combustion characteristics of biomass when co-firing with coal. The combustion characteristics were verified using experimental results including reactivity from the TGA and Unburned carbon(UBC) data from the DTF. The experiment also analyzed with the variation of the biomass blending ratio and biomass particle size. It was determined that increasing the biomass blending ratio resulted in incomplete chemical reactions due to insufficient oxygen levels because of the rapid initial combustion characteristics of the biomass. Thus, the optimum blending condition of the biomass based on the results of this study was found to be 5 while oxygen enrichment reduced the increase of UBC that occurred during combustion of blended biomass and coal.

  12. Recovery of clean coal from polymer flocculated raw coal slurry

    Parekh, B.K.; Chen, Z. [Center for Applied Energy Research, Lexington, KY (US)


    The recovery of fine clean coal from waste streams using column flotation is recognized as an efficient and economical technique. However, due to the low percent solids (around 3% by weight) found in these fine waste slurries, the flotation columns have low capacities and are, thus, underutilized. In this study, a 3% (by weight) solids suspension of Upper Freeport coal was flocculated with polymers and concentrated to 10% (by weight) solids. The flocculated slurry was then floated using 250 g/t No. 2 fuel oil and 250 g/t MIBC, which provided a clean coal with 12% ash at an 80% yield. The results showed that flocculated coal could be floated effectively. Zeta potential and contact-angle data showed that the presence of polymer on the surface of the coal did not affect its hydrophobicity, and in some cases it improved the hydrophobicity as indicated by larger contact angles.

  13. Column: lef

    Reep, Frans van der


    1e alinea column: Ook in je beleggingsbeslissingen is het voor echte performance wellicht tijd om eens voorbij best practices (dan word je namelijk hoogstens tweede) te kijken naar next practices. Als je op zeker speelt, verdien je weinig geld. Want anderen gingen je al voor. Maar kun je nog meer op

  14. Co-firing straw with coal in a swirl-stabilized dual-feed burner: modelling and experimental validation

    Yin, Chungen; Kær, Søren Knudsen; Rosendahl, Lasse


    This paper presents a comprehensive computational fluid dynamics (CFD) modelling study of co-firing wheat straw with coal in a 150 kW swirl-stabilized dual-feed burner flow reactor, in which the pulverized straw particles (mean diameter of 451μm) and coal particles (mean diameter of 110.4μm......-lean core zone; whilst the coal particles are significantly affected by secondary air jet and swirled into the oxygen-rich outer radius with increased residence time (in average, 8.1s for coal particles vs. 5.2s for straw particles in the 3m high reactor). Therefore, a remarkable difference in the overall...

  15. Experimental Evaluation of Permeability of Coal in Supercritical CO2 and N2 Injection Under Stress and Strain Restricted Conditions

    KIYAMA, Tamotsu; NISHIMOTO, Soshi; FUJIOKA, Masaji; XUE, Zique; MIYAZAWA, Daisuke; ISHIJIMA, Yoji


    .... In this study, the strain and stress constraint conditions were created in-laboratory and N2 and supercritical CO2 were injected repeatedly in a coal specimen for observation of the permeability, Vp...

  16. Selective detachment process in column flotation froth

    Honaker, R.Q.; Ozsever, A.V.; Parekh, B.K. [University of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering


    The selectivity in flotation columns involving the separation of particles of varying degrees of floatability is based on differential flotation rates in the collection zone, reflux action between the froth and collection zones, and differential detachment rates in the froth zone. Using well-known theoretical models describing the separation process and experimental data, froth zone and overall flotation recovery values were quantified for particles in an anthracite coal that have a wide range of floatability potential. For highly floatable particles, froth recovery had a very minimal impact on overall recovery while the recovery of weakly floatable material was decreased substantially by reductions in froth recovery values. In addition, under carrying-capacity limiting conditions, selectivity was enhanced by the preferential detachment of the weakly floatable material. Based on this concept, highly floatable material was added directly into the froth zone when treating the anthracite coal. The enriched froth phase reduced the product ash content of the anthracite product by five absolute percentage points while maintaining a constant recovery value.

  17. Latent methane in fossil coals

    A.D. Alexeev; E.V. Ulyanova; G.P. Starikov; N.N. Kovriga [Academy of Sciences of Ukraine, Donetsk (Ukraine). Institute for Physics of Mining Processes


    It is established experimentally using 1H NMR wide line spectroscopy that methane can exist in coals not only in open or closed porosity and fracture systems but also in solid solutions in coal substance, in particular, under methane pressure 2 MPa or higher. Methane dissolved in coal minerals reversibly modifies their lattice parameters as determined from X-ray diffraction analysis. Co-existence of these methane forms in fossil coals causes multi-step desorption kinetics. It is shown experimentally that the long-term latent methane desorption is effected mainly by closed porosity, which in turn is determined by coal rank. 21 refs., 3 figs., 2 tabs.

  18. Eruption column physics

    Valentine, G.A.


    In this paper the author focuses on the fluid dynamics of large-scale eruption columns. The dynamics of these columns are rooted in multiphase flow phenomena, so a major part of the paper sets up a foundation on that topic that allows one to quickly assess the inherent assumptions made in various theoretical and experimental approaches. The first part is centered on a set of complex differential equations that describe eruption columns, but the focus is on a general understanding of important physical processes rather than on the mathematics. The author discusses briefly the relative merits and weaknesses of different approaches, emphasizing that the largest advances in understanding are made by combining them. He then focuses on dynamics of steady eruption columns and then on transient phenomena. Finally he briefly reviews the effects of varying behavior of the ambient medium through which an eruption column moves. These final sections will emphasize concepts and a qualitative understanding of eruption dynamics. This paper relies on principles of continuum mechanics and transport processes but does not go into detail on the development of those principles. 36 refs., 36 figs., 3 tabs.

  19. Experimental Determination of Heat Transfer Coefficient in Stirred Vessel for Coal-Water Slurry Based on the Taguchi Method

    C. M. Raguraman


    Full Text Available Heat transfer in stirred vessels is important because process fluid temperature in the vessel is one of the most significant factors for controlling the outcome of process. In this study, the effects of some important design parameters for coal-water slurry in agitated vessel used in coal gasification such as stirrer speed, location of stirrer, D/d ratio, and coal-water ratio were investigated and optimized using the Taguchi method. The experiments were planned based on Taguchi’s orthogonal array with each trial performed under different levels of design parameter. Signal-to-noise (S/N analysis and analysis of variance (ANOVA were carried out in order to determine the effects of process parameter and optimal factor’s level settings. Finally, confirmation tests verified that the Taguchi method achieved optimization of heat transfer coefficient in agitated vessel.

  20. Improvements of the Computerized Data Acquisition System for 25MWt Experimental Facility of Coal-fired MHD Generator


    This paper introduces the design and development of a new computerized data acquisition system for the coal-fired magnetohydrodynamical (MHD) electrical power generation experiments. Compared to the previous system, it has a higher sampling rate and an improved simultaneity performance. It also improves the data collection method and sensor design for the measurement of Faraday voltages and Faraday currents. The system has been successfully used in many regular MHD generator tests. It provides an excellent base for the future research and development of the Coal-fired MHD electrical power generation.

  1. Underground Coal Thermal Treatment

    Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Deo, M. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Sarofim, A. [Univ. of Utah, Salt Lake City, UT (United States); Gueishen, K. [Univ. of Utah, Salt Lake City, UT (United States); Hradisky, M. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States); Mandalaparty, P. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, H. [Univ. of Utah, Salt Lake City, UT (United States)


    The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal's carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO2 sequestration.

  2. Experimental study on temperature distribution of membrane water wall in an ultra-supercritical pressure once-through boiler burning zhundong coal

    He, Honghao; Li, Wenjun; Zeng, Jun; Xie, Guohong; Peng, Min; Duan, Xuenong


    Taking an ultra-supercritical pressure once-through boiler as an example, the temperature distribution of the lower membrane water wall is investigated experimentally, the conclusion reveals that increasing the proportion of Zhundong coal can effectively reduce the district heat load, which benefits the temperature uniformity in the lower membrane water wall. When the boiler being operated at middle load, the temperature deviation in lower membrane water wall increase simultaneously, one of the reasons is that the restriction orifice could not adjust the flow rate of working fluid as expected. By adjusting boiler performance, the temperature uniformity of lower membrane water wall can be improved to a certain degree.

  3. Investigation of Effect of Influent Concentration and Flow Rate on Nickel Biosorption using Protonated Cystoseira indica Brown Alga in a Packed Bed Column and Modeling the Experimental Data

    Ali Reza Keshtkar


    Conclusion: The results of this study are complementary of the batch equilibrium sorption experiments. Therefore, from process viewpoint, this biomass can be proposed in the sorption columns as a sorbent for nickel ions.

  4. Crossing point temperature of coal

    Qi Xuyao; Deming Wang; James A. Milke; Xiaoxing Zhong


    A further understanding of the self-heating of coal was obtained by investigating the crossing point temperature (CPT) of different ranks of coal. The tests were carried out using a self-designed experimental system for coal self-heating. 50 g (±0.01 g) of coal particles ranging from 0.18 mm to 0.38 mm in size were put into a pure copper reaction vessel attached to the center of a temperature programmed enclosure. The temperature program increased the temperature at a rate of 0.8 ℃/min. Dry air was permitted to flow into the coal reaction vessel at different rates. The surrounding temperature and the coal temperature were monitored by a temperature logger. The results indicate that CPT is affected by coal rank, moisture, sulfur,and the experimental conditions. Higher ranked coals show higher CPT values. A high moisture content causes a delay phenomenon during the self-heating of the coal. Drying at 40 ℃ decreases the effects of moisture. The reactivity of sulfur components in the coal is low under dry and low-temperature conditions.These components form a film that covers the coal surface and slightly inhibits the self-heating of the coal.The flow rate of dry air, and the heating rate of the surroundings, also affect the self-heating of the coal. The most appropriate experimental conditions for coal samples of a given weight and particle size were determined through contrastive analysis. Based on this analysis we propose that CPTs be determined under the same, or nearly the same conditions, for evaluation of the spontaneous combustion of coal.

  5. Experimental studies on Gas—Particle Flows and Coal Combustion in New Generation Spouting—Cyclone COmbustor

    D.X.Wang; Z.H.Ma; 等


    Besed on previous studies,an improved non-slagging spouting-cyclone combustor with two-stage combustion,organized in perpendicularly vortexing flows,is developed for clean coal combustion applied is small-size industrial furnaces and domestic furnaces.The isothermal model test and the combustion test give some encouraging results.In this study,further improvement of the gemoetrical configuration was made,a visualization method and a LDA system were used to study the gas-particle flow behavior and the temperature and gas composition in combustion experiments were measured by using thermocouples and a COSA-6000-CD Portable Stack Analyzer.Stronger recirculation in the sopouting zone and the strongly swirling efect in the cyclone zone were obtained in the improved combustor.The combustion temperature distribution is uniform.These results indicate that the improved geometrical configuration of the combustor is favorable to the stabilization of coal flame and the intensification of coal combustion.and is provides a basis for the practical application of this technique.

  6. 不同因素对煤吸氧量、热焓影响的试验研究%Experimental Study on Effects of Different Factors on Coal Oxygen Absorption and Enthalpy

    朱红青; 屈丽娜; 沈静; 和超楠


    In order to study effects of different factors ( heating rate, granularity, oxygen concentration) on coal oxygen absorption, coal enthalpy, based on the experimental of TG-DSC to research their variations on the TG curves of quality weight gain (that is coal oxygen absorption) and DSC curves of coal enthalpy size by the coal samples of temperature-programmed from No. 1 to No. 5. The experimental results showed that: with heating rate increases, the coal oxygen absorption is decreased gradually, and it exists exponential relationship with the coal oxygen absorption, but the trend of thermal enthalpy is first decreased and then increased; With the oxygen concentration increased, the coal oxygen absorption is first decreased and then increased, but the thermal enthalpy is first increased and then decreased, when the oxygen volume fraction is 12% ,the coal oxygen absorption is minimum but the thermal enthalpy is maximum; The larger granularity,the greater coal oxygen absorption, however, the thermal enthalpy is increased first and then decreased, when the granularity is 140—160 mesh, the thermal enthalpy is maximum. The experimental results reveal the influence of different factors on coal oxygen absorption and enthalpy value.%为研究升温速率、氧气浓度、粒度等因素对煤吸氧量、热焓值的影响规律,基于热重-差示扫描量热法(TG-DSC)试验,考察1-5号煤样在程序升温过程中,其TG曲线的质量增重情况(即煤吸氧量)及DSC曲线中煤热焓值的变化规律.试验结果表明:随着升温速率增大,煤吸氧量逐渐减小并与之呈指数关系,而热焓值则呈先减小后增大的趋势;氧气浓度越大,煤吸氧量先减小后增大,而热焓值则先增大后减小,在氧气体积分数为12%时吸氧量最小而热焓值最大;粒度越大,煤吸氧量越大,而热焓值则先增大后减小且在140 ~160目时达到最大.

  7. 白银含铜废石生物柱浸试验研究%Experimental Research on Column Bioleaching of Copper-containing Waste Rock in Baiyin

    刘厚明; 舒荣波; 王晓慧; 程蓉; 梁友伟


    Research on leaching experiment by adopting bioleaching method was carried on the copper-containing waste rock in Baiyin. According to the ore properties and bioleaching characteristic, the influence of grain size,types of leaching bacteria, leaching temperature and leaching time on leaching results was studied. The results showed that the bioleaching of copper-containing waste rock using moderate thermoacidophile BioMetal SM-3 was feasible. And the relatively high leaching rate ofcopper( >60% ) was obtained for size of ?5mm after being bioleached for 190 days. The influence of ore size on metal leaching rate and column stability was also researched. When it was applied to industry, the ore should be crushed to -20mm before ore stacking to ensure the stability of ore heap and metal leaching rate. The obtained experimental parameter revealed the rule and process-controlled factors of the copper-containing waste rock in Baiyin, which can guide the industrial production of the copper-containing waste rock in Baiyin by adopting the method of bioleaching.%以白银矿区存有的大量含铜废石为研究对象,采用生物柱浸法对其进行浸出试验研究.结合白银废石铜矿特点与细菌浸出特性,分别研究不同矿样粒度,浸矿菌种,浸矿温度以及浸出时间等对浸出结果的影响.研究结果表明,采用BioMetal SM-3中等嗜热嗜酸菌浸出白银废石堆矿样是可行的,可在较短的浸出时间(190d)内获得较高的铜浸出率(-15mm粒级Cu浸出率>60%).通过对比不同矿样粒度对金属浸出率与矿柱稳定性的影响,在工业应用时,为保证矿堆的稳定性和金属浸出速率,建议将矿石破碎到-20 mm粒级然后筑堆..本试验研究所取得的试验参数揭示了白银含铜废石生物浸出规律及过程控制因素,对白银含铜废石采用生物堆浸工业生产具有指导意义.

  8. Experimental investigation on NOx emission characteristics of a new solid fuel made from sewage sludge mixed with coal in combustion.

    Zhai, Yunbo; Zhu, Lu; Chen, Hongmei; Xu, Bibo; Li, Caiting; Zeng, Guangming


    In this article, a new briquette fuel (SC), which was produced by the mixture of coal fines (25.9%), sewage sludge (60.6%), lignin (4.5%), tannic acid (4.5%) and elemental silicon (4.5%), was provided. Then, in a high temperature electric resistance tubular furnace, the total emissions of NO2 and NO, effects of combustion temperature, air flow rate and heating rate on NOx (NO, NO2) emissions of SC were studied during the combustion of SC; furthermore, effects of additives on hardness were also analysed, and the X-ray photoelectron spectroscopy was applied to investigate the reduced NOx emission mechanism. The research results showed that, compared with the characteristics of briquette fuel (SC0) produced only by the mixture of coal and sewage sludge (the ratio of coal to sewage sludge was the same as that of SC), the Meyer hardness of SC was 12.6% higher than that of SC0 and the emissions of NOx were 27.83% less than that of SC0 under the same combustion conditions. The NOx emissions of SC decreased with the adding of heating rate and increased with the rise of air flow rate. When the temperature was below 1000 °C, the emissions of NOx increased with the elevated temperature, however, further temperature extension will result in a decreasing in emissions of NOx. Furthermore, the X-ray photoelectron spectroscopy results proposed that the possible mechanism for the reduction of NOx emissions was nitrogen and silicon in SC to form the compounds of silicon and nitrogen at high temperatures.

  9. Experimental Study on Mining Influence in Coal Mining Area with Loose Sand Bed%松散沙层煤矿区采动影响试验

    刘立忠; 李虎民; 姜升


    The development and sustainability of intensive coal mines are restricted seriously by the coal mining under villages,which needed to be addressed. The current method is to relocate the involved villages,but there are some disadvanta-ges such as high cost,lack of land and the residents′reluctance to move. Therefore,reconstruction of the villagers′houses be-fore mining in the would-be subsidence area serves as a new way to prevent the coal mining under villages. In Xiaojihan Coal Mine,the observation of building anti-deformation and surface movement are made respectively in the testing building and the observation stations in order to make experimental study on the mining effect and mining without relocation. The result shows that the villagers′houses with anti-deformation structure could be resistant to the mining influence. It is feasible to make mining without relocation in the mining area with good application value.%村庄压煤问题严重制约着村庄密集型煤矿的发展和生产接续,亟待解决。目前的解决方法是对涉及到的村庄进行搬迁,但这样做有成本高、用地指标紧张和农民不愿搬离原址等弊端。因此,充分利用拟沉陷区进行村庄采前就地重建为村庄压煤问题的解决提供了新思路。通过小纪汗煤矿抗变形结构试验房和地表移动变形观测站,进行建筑物变形观测和地表移动变形观测,开展采动区影响和不搬迁开采试验研究。结果表明:采取相应抗变形结构的民房可以抵抗该矿的采动影响,可以进行该地区的不搬迁开采推广,具有很好的应用价值。

  10. Redesign of Industrial Column Flotation Circuits Based on a Simple Residence Time Distribution Model


    The potential for improved selectivity has made column flotation cells a popular choice for upgrading fine coal. Unfortunately, recent production data from full-scale column plants indicate that many industrial installations have failed to meet original expectations in terms of clean coal recovery. Theoretical studies performed using a simple dispersion model showed that this inherent shortcoming could be largely minimized by reconfiguring the columns to operate in series as a cell-to-cell ci...

  11. Experimental studies on the group ignition of a cloud of coal particles: Volume 2, Pyrolysis and ignition modeling. Final report, August 15, 1988--October 15, 1991

    Annamalai, K.; Ryan, W.


    The primary objectives of this work are to formulate a model to simulate transient coal pyrolysis, ignition, and combustion of a cloud of coal particles and to compare results of the program with those reported in the literature elsewhere.

  12. The utilization of coal mining wastes as filling materials in reinforced earth structures. III. Construction of a full scale experimental structure; Utilizacion de los esteriles del carbon como material de relleno en estructuras de tierra reforzada. II. Construccion de una estructura experimental

    CaNibano Gonzalez, J.; Martinez, C.; Gonzalez, M.R. [HUNOSA. Programa Desarrollo Esteriles. Oviedo (Spain); Pardo, F.; SopeNa, L. [CEDEX. Laboratorio Geotecnia, Madrid (Spain); Torres, M. [Escuela Tecnica Superior de Ingenieros de Minas, Oviedo (Spain); Perez, J.J. [MOPTMA. Demarcacion Carreteras del Estado, Oviedo (Spain)


    This article describes the construction of a full scale experimental structure in which coal mining wastes (mine stones) were utilized as a filling material. In such structure, which was 20 m long and 2 high coal mining wastes from two different tips were tested together with different types of reinforcing frames such as metal bands, geomeshes and Paraweb (Freyssisol) bands. Also, thermocouples were placed at different heights. On the other hand, the said structure was subjected to 3.085 passes of a truck having a ballast of 10.5 tons on its rear axle. The performance of the coal mining wastes was completely satisfactory. (Author) 3 refs.

  13. Experimental research on influencing factors of wet removal of NO from coal-fired flue gas by UV/H2O2 advanced oxidation process


    Wet removal of NO from coal-fired flue gas by UV/H2O2 Advanced Oxidation Process (AOP) were investigated in a self-designed UV-bubble reactor. Several main influencing factors (UV intensity, H2O2 initial concentration, initial pH value, solution temperature, NO initial concentration, liquid-gas ratio and O2 percentage content) on the NO removal efficiency were studied. The results showed that UV intensity, H2O2 initial concentration, NO initial concentration and liquid-gas ratio are the main influencing factors. In the best conditions, the highest NO removal efficiency by UV/H2O2 advanced oxidation process could reach 82.9%. Based on the experimental study, the influencing mechanism of the relevant influencing factors were discussed in depth.

  14. Slurry bubble column hydrodynamics

    Rados, Novica

    Slurry bubble column reactors are presently used for a wide range of reactions in both chemical and biochemical industry. The successful design and scale up of slurry bubble column reactors require a complete understanding of multiphase fluid dynamics, i.e. phase mixing, heat and mass transport characteristics. The primary objective of this thesis is to improve presently limited understanding of the gas-liquid-solid slurry bubble column hydrodynamics. The effect of superficial gas velocity (8 to 45 cm/s), pressure (0.1 to 1.0 MPa) and solids loading (20 and 35 wt.%) on the time-averaged solids velocity and turbulent parameter profiles has been studied using Computer Automated Radioactive Particle Tracking (CARPT). To accomplish this, CARPT technique has been significantly improved for the measurements in highly attenuating systems, such as high pressure, high solids loading stainless steel slurry bubble column. At a similar set of operational conditions time-averaged gas and solids holdup profiles have been evaluated using the developed Computed Tomography (CT)/Overall gas holdup procedure. This procedure is based on the combination of the CT scans and the overall gas holdup measurements. The procedure assumes constant solids loading in the radial direction and axially invariant cross-sectionally averaged gas holdup. The obtained experimental holdup, velocity and turbulent parameters data are correlated and compared with the existing low superficial gas velocities and atmospheric pressure CARPT/CT gas-liquid and gas-liquid-solid slurry data. The obtained solids axial velocity radial profiles are compared with the predictions of the one dimensional (1-D) liquid/slurry recirculation phenomenological model. The obtained solids loading axial profiles are compared with the predictions of the Sedimentation and Dispersion Model (SDM). The overall gas holdup values, gas holdup radial profiles, solids loading axial profiles, solids axial velocity radial profiles and solids

  15. 钢筋混凝土T形柱斜撑框架抗震性能试验研究%Experimental Study on Earthquake Resistant Behaviour of R. C. T-shaped Column Braced Frame

    李晓轩; 严士超


    对1/2缩尺比例、单层单跨的3榀钢筋混凝土T形柱斜撑框架和1榀钢筋混凝土T形柱框架在低周反复水平荷载作用下进行了试验研究,分析了钢筋混凝土异形柱斜撑框架的承载力、刚度、延性、恢复力特性、耗能能力及破坏机制等。研究结果表明,钢筋混凝土T形柱斜撑框架结构具有良好的抗震性能。%Based on the experimental study of 3 R. C. T-shaped column bracedframe models and 1 R. C. T-shaped column frame model of 1/2 scale single storey and single span under low frequency cyclic and reversed lateral loads, the strength, stiff ness, ductility, restoring force characteristics, energy consumption ability as well as the failure mechanism of R. C. T-shaped column braced frame structure have been carried out. It was shown by the experimental results that the earthquake resistant behaviour of R. C. T-shaped olumn braced frame structure is satisfactory.

  16. Environmental impact assessment and selenium transformation in coal mine spoils

    Atalay, A.; Koll, K.J.


    This quarterly report addresses the continued field investigation of a selected coal mining site in Oklahoma. Table 1 (appendix) portrays all the data (field measurements) taken at the Henryetta experimental site. An analysis of this data would be useful in providing information for potential Se migration from a coal mining site and the distribution of Se in a soil profile of land reclaimed to its pristine state. Also addressed is the methodology developed (1) for SeO{sub 4}{sup 2{minus}} and SeO{sub 3}{sup 2{minus}} adsorption on selected soils, (2) leachate migration through a cell column using soil samples from the Henryetta reclamation site, and (3) chemical transformation of SeO{sub 4}{sup 2{minus}} under harsh chemical and conditions.

  17. Experimental study on seismic behavior of latticed system columns with RC bracing structure%带RC支撑格构化体系柱的抗震性能试验研究

    黄靓; 王鹏; 易楚军; 易宏伟


    In order to explore the "strong column weak beam" seismic design principles of reinforced concrete frames, two lattice system columns with V-braces and X-braces and a test specimen without brace were designed for cyclic tests. Based on the test results, the cracking load, ultimate bearing capacity and failure modes were obtained. Hysteretic curves, skeleton curves, deformation and Ductility coefficient ability of seismic performance of the latticed system columns with RC braces were analyzed and compared with the specimens without braces. Experimental results indicate that good seismic performance can be obtained for the Latticed System Columns with RC braces, and its resistant lateral stiffness increases obviously. For lattice system columns with RC braces,the plastic hinges of braces and beams unusually appeare in advance, which makes the structure easy to realize the target of seismic design of " strong column weak beam" , however, the lattice system columns without the RC braces do not show such trend.%为探索实现钢筋混凝土框架中的“强柱弱梁”的抗震设计原则,该文设计两个支撑形式分别为人字形、交叉形的格构化体系柱和一个无支撑的格构化体系柱试件,并对其进行低周期反复荷载试验.得出格构化体系柱的开裂荷载、极限承载力和破坏形态,分析带RC支撑的格构化体系柱的滞回曲线、骨架曲线、变形能力、延性等抗震性能,并和无支撑的格构化体系柱进行对比分析.分析结果表明:带RC支撑的格构化体系柱的极限承载力、抗侧刚度等抗震性能较无支撑格构化体系柱有明显的提高.在带RC支撑的格构化体系柱中,支撑和梁往往先于柱子出现塑性铰,使结构容易实现“强柱弱梁”的抗震设计目标,而不带RC支撑的格构化体系柱却很难实现.

  18. The production of high load coal-water mixtures on the base of Kansk-Achinsk Coal Basin

    Demidov, Y.; Bruer, G.; Kolesnikova, S. [Research and Design Institute for Problems of Development of Kansk-Achinsk Coal Basin (KATEKNilugol), Krasnoyarsk (Russian Federation)


    The results of the {open_quotes}KATEKNIIugol{close_quotes} work on the problems of high load coal-water mixtures are given in this article. General principles of the mixture production, short characteristics of Kansk-Achinsk coals, the experimental results of the coal mixture production on a test-industrial scale, the suspension preparation on the base of coal mixtures, technical-economical indexes of tested coal pipeline variants based on Kansk-Achinsk coals are described.

  19. Experimental Analysis on Seismic Performance of Steel Bracing Bound-Column Component%钢支撑束柱抗震性能试验研究

    陆烨; 刘青; 李国强; 刘玉姝


    通过试验和有限元理论对比研究了钢支撑束柱的抗震性能和破坏特性。试验模型采用2层钢支撑束柱构件,其中钢支撑为长肢相并的双角钢支撑。试验共分为3组,1组为单调加载试验,另外2组为滞回性能试验。另对钢支撑束柱的抗震性能进行了有限元理论分析,经试验结果验证,得到了钢支撑束柱试件的抗侧承载力、刚度及滞回性能。研究表明,钢支撑束柱的承载力、刚度主要来自钢支撑,而束柱外框架部分的贡献很小。钢支撑束柱的破坏只发生在钢支撑中,外框架部分没有任何损坏。%The seismic resistant performance and failure mechanism of the steel bracing Bound-Column were analyzed with tests and the finite element method .Two-story steel bracing Bound-Column test specimen was selected .The braces adopt long leg back-back double angle .Tests were divided into three groups , including one monotonic loading test and two cyclic tests . Lateral load-bearing capacity , stiffness and hysteretic behavior of the steel bracing Bound-Column were obtained by the comparison of test results and the finite element method .Results show that the steel brace of Bound-Column contributes a lot to its load capacity and stiffness ,while the external frame provides little lateral rigidity and capacity .Bound-Column failure occurs only in the steel braces ,while the external frame is with no damage .


    杨远龙; 杨华; 张素梅


    异形柱结构较传统框架结构能有效地改善建筑内部的使用空间,但目前应用较多的钢筋混凝土异形柱存在高轴压比下抗震性能不足,对水平荷载的方向性非常敏感等问题,其房屋高度和抗震设防烈度受到严格限制,制约了其在高设防烈度地区进一步的推广和应用.型钢混凝土异形柱相对于钢筋混凝土异形柱,其抗震性能有所改善,为此,该文提出了内部设置格构式圆钢管的T形型钢混凝土柱.进行了格构式型钢混凝土柱轴压、偏压和压弯滞回性能的三组系列试验,研究了上述试件的破坏模式与力学性能,分析了格构式型钢骨架的作用机理和对混凝土破坏模式的影响.试验结果表明,内部格构式型钢骨架能够保持整体工作,同时限制了型钢混凝土的粘结滑移,一定程度上延缓了混凝土的破坏.相对于钢筋混凝土试件,在轴压和偏压荷载工况下,型钢混凝土的承载力和延性显著提高;在压弯滞回荷载工况下,型钢混凝土的承载力和耗能性能得到改善.%Special-shaped column structures might improve residential architectural space effectively, compared with traditional frame structures. However, the widespread special-shaped reinforced concrete (RC) columns present insufficient aseismic behavior with a high axial load ratio and sensitivity to the horizontal loading direction, and have strict limitations in aseismic behaviors, in respect to applicable building height and aseismic fortification intensity, which hampers further generalization and application of special-shaped columns in a high aseismic fortification zone. Special-shaped steel reinforced concrete (SRC) columns behave advantages on the aseismic behaviors over special-shaped RC columns. A kind of T-shaped steel reinforced concrete column with latticed steel tubes in the sectional branch components is introduced. Three series of experimental investigations on the axial, eccentric

  1. Automated Composite Column Wrapping

    ECT Team, Purdue


    The Automated Composite Column Wrapping is performed by a patented machine known as Robo-Wrapper. Currently there are three versions of the machine available for bridge retrofit work depending on the size of the columns being wrapped. Composite column retrofit jacket systems can be structurally just as effective as conventional steel jacketing in improving the seismic response characteristics of substandard reinforced concrete columns.

  2. Novel techniques for slurry bubble column hydrodynamics

    Dudukovic, M.P.


    The objective of this cooperative research effort between Washington University, Ohio State University and Exxon Research Engineering Company was to improve the knowledge base for scale-up and operation of slurry bubble column reactors for syngas conversion and other coal conversion processes by increased reliance on experimentally verified hydrodynamic models. During the first year (July 1, 1995--June 30, 1996) of this three year program novel experimental tools (computer aided radioactive particle tracking (CARPT), particle image velocimetry (PIV), heat probe, optical fiber probe and gamma ray tomography) were developed and tuned for measurement of pertinent hydrodynamic quantities, such as velocity field, holdup distribution, heat transfer and bubble size. The accomplishments were delineated in the First Technical Annual Report. The second year (July, 1996--June 30, 1997) was spent on further development and tuning of the novel experimental tools (e.g., development of Monte Carlo calibration for CARPT, optical probe development), building up the hydrodynamic data base using these tools and comparison of the two techniques (PIV and CARPT) for determination of liquid velocities. A phenomenological model for gas and liquid backmixing was also developed. All accomplishments were summarized in the Second Annual Technical Report. During the third and final year of the program (July 1, 1997--June 30, 1998) and during the nine months no cost extension, the high pressure facility was completed and a set of data was taken at high pressure conditions. Both PIV, CT and CARPT were used. More fundamental hydrodynamic modeling was also undertaken and model predictions were compared to data. The accomplishments for this period are summarized in this report.

  3. Grouting Treatment for Water Gushing of Collapsing Columns with Centralized Auxiliary Transportation for Lower Group Coal in Wulihou Mine%五里堠煤矿下组煤集中辅助运输下山陷落柱出水的注浆治理



    为治理五里堠煤矿下组煤集中辅助运输下山陷落柱涌水问题,综合地面三维地震勘探、井下钻探、注浆加固技术,提出了陷落柱出水的治理方案和施工措施。经过治理实践,表明涌水量明显减小,注浆效果良好,取得显著效益。%To solve water gushing of collapsing columns with centralized auxiliary transportation for lower group coal in Wulihou Mine, ground three -dimensional seismic exploration, drilling, and grouting reinforcement technology were synthesized to propose a treatment plan and detailed construction measures. The practice showed that water gushing reduced dramatically with ideal grouting effect and obvious economic benefits.

  4. Experimental investigation of mobile small-scale liquefier for 10000 NM3/D of coal bed methane gas

    Sun, Zhaohu; Wu, J. F.; Gong, Maoqiong; Guo, Ping


    There is a growing recognition that unconventional sources of gas, such as shale gas, coal bed methane (CBM) and deep tight gas will contribute a significant component of future gas supplies as technologies evolve. In recent years, the interest in such source of gas utilization technologies based on small-scale LNG production has been rising steeply. In this paper, a mobile liquefier prototype for 10000 Nm3/d of CBM has been designed, constructed and tested. It has two cascade refrigeration systems. The high-temperature refrigeration system will pre-cool the resource gas to 5oC, and the low-temperature refrigeration system will continue to cool the resource gas to the liquefied point with a Mixed Refrigerant Cycle (MRC). The kernel compressor is a conventional oil-lubricated air-conditioning compressor with the discharge pressure of 2.0 MPa. The main heat exchanger is plate-fin heat exchanger with four passages. A series of experiments have been done on the prototype liquefier at different resource gas pressures and environmental temperatures. It is less than one hour from the start of the equipment to the existence of LNG. The maximum production of LNG is about 20 m3/d when a stream of about 12500 Nm3/d of pure CBM at a process pressure of 1.3 MPa is liquefied. The energy consumption of liquefying 1 Nm3 methane is 0.612 kWh.

  5. Comparison of the Experimental and Numerical Results of Modelling a 32-Oscillating Water Column (OWC, V-Shaped Floating Wave Energy Converter

    John V. Ringwood


    Full Text Available Combining offshore wind and wave energy converting apparatuses presents a number of potentially advantageous synergies. To facilitate the development of a proposed floating platform combining these two technologies, proof of concept scale model testing on the wave energy converting component of this platform has been conducted. The wave energy component is based on the well-established concept of the oscillating water column. A numerical model of this component has been developed in the frequency domain, and the work presented here concerns the results of this modelling and testing. The results of both are compared to assess the validity and usefulness of the numerical model.

  6. Experimental Study on the Waste Heat Utilization of Air Compressor in Coal Mine%煤矿空压机废热利用实验研究

    王建学; 牛永胜; 袁静


    针对目前空压机排风废热的回收利用存在的问题,设计了采用热泵技术对空压机废热的回收方案。分析了空压机废热源热泵系统的工作原理,并建立了实验台进行实验研究,测试了不同的空压机排风温度、热水出水温度等因素对空压机废热源热泵系统性能的影响。通过对空压机废热源热泵系统在山西某煤矿的应用的举例,分析了煤矿空压机废热利用可收获的经济效益和社会效益。%Aiming at the current problems for the recycling and utilization of air compressor exhaust waste heat,it designed the recycling plan of air compressor waste heat with heat pump technology.The working principle of the heat pump system of air compressor waste heat source was analyzed,and the experiment table was established to do experimental research,test factors such as different air compressor exhaust temperature,outlet temperature of hot water which influence on the performance of the heat pump system.Through the exemplifying of the air compressor waste heat source heat pump system application to a coal mine in Shanxi province,it analyzed the economic benefit and social benefit which could be obtained by the air compressor waste heat utilization in the coal mine.

  7. 不同再生骨料取代率混凝土柱耐火性能试验研究%Experimental Study on Fire Resistant Performance of Recycled Concrete Columns with Different Replacement Rate of Recycled Aggregate

    曹万林; 边建辉; 董宏英; 张建伟


    为研究不同再生骨料取代率混凝土柱的耐火性能,进行了3个足尺再生混凝土柱在竖向荷载和温度场耦合作用下的升温耐火试验.其中,2个试件再生粗骨料取代率为100%,细骨料为天然砂的半再生混凝土柱;1个试件为再生粗、细骨料取代率均为100%的全再生混凝土柱.在试验基础上,比较分析了各试件的截面温度变化、耐火极限、轴向变形、侧向挠度和破坏形态.研究表明:相同轴压比条件下,半再生混凝土柱的耐火极限随着混凝土强度的提高而降低;混凝土强度变化对温度场分布规律影响较小;半再生混凝土柱与全再生混凝土柱相比,混凝土材料性能退化较慢,耐火性能较好.%In order to investigate the fire resistant performance of the recycled concrete columns with different replacement rate of recycled aggregate;three full-sized recycled concrete columns were designed and tested under high temperature and unchanged vertical load. Two of the specimens were made from recycled concrete with 100% of recycled coarse aggregate and 100% of natural fine aggregate;which was called 50% recycled aggregate concrete. The other one was made from recycled concrete with 100% of recycled coarse aggregate and 100% of recycled fine aggregate;which was called 100% recycled aggregate concrete here. Based on the experimental study;several parameters were comparatively analyzed;including the temperature variation at the cross section;fire endurance;vertical displacement;lateral deflection;and failure modes of specimens. Results show that the fire resistant endurance for recycled coarse aggregate concrete column decreases with the concrete strength increases. The concrete compressive strength has little infuence on the temperature field of columns. Compared to the column with 100% recycled aggregate concrete;the column with 50% recycled aggregate concrete has better fire resistant performance and its material property

  8. Effects of coal rank on the chemical composition and toxicological activity of coal liquefaction materials

    Wright, C.W.; Dauble, D.D.


    This report presents data from the chemical analysis and toxicological testing of coal liquefaction materials from the EDS and H-Coal processes operated using different ranks of coal. Samples of recycle solvent from the bottoms recycle mode of the EDS direct coal liquefaction process derived from bituminous, sub-bituminous, and lignite coals were analyzed. In addition, the H-Coal heavy fuel oils derived from bituminous and sub-bituminous coals were analyzed. Chemical methods of analysis included adsoprtion column chromatography, high-resolution gas chromatography, gas chromatography/mass spectrometry, and low-voltage probe-inlet mass spectrometry. The toxicological activity of selected samples was evaluated using the standard microbial mutagenicity assay, an initiation/promotion assay for mouse-skin tumorigenicity, and a static bioassy with Daphnia magna for aquatic toxicity of the water-soluble fractions. 22 refs., 16 figs., 14 tabs.

  9. Experimental study on ultimate bearing capacity of axially compressed high strength steel columns%高强钢焊接箱形柱轴心受压极限承载力试验研究

    李国强; 王彦博,; 陈素文


    An experimental and theoretical study was presented on ultimate bearing capacity of axially compressed high strength steel columns. The experimental program included 7 welded box columns of 3 different cross sections which were welded with 11 mm-thick Q460 high strength steel plates made in China. The FEA models were built up according to measured sizes of members and tension coupon test results. And initial geometric imperfections and residual stress were taken into account in the FEA models. The experimental result shows that the stability coefficients of welded box columns of high strength steel are higher than the values of type c column curve in GB 50017--2003, and even higher than the values of type b curve for most of the specimens. However, due to the limited test result, the adoption of type b curve needs further verification. The FEA result agrees well with experimental result and could be a valid supplement of test data.%为了研究高强钢中厚板焊接箱形柱的极限承载力,以11 mm厚国产Q460高强钢中厚板制作了7个焊接箱形柱进行轴心受压试验。试件共包含宽厚比8、12、18三种截面,长细比分别为35、50、70。根据试件的实测尺寸、钢材的力学性能建立有限元模型,以初始缺陷的形式考虑了试件的初始挠度、初始偏心及焊接残余应力,分析预测了试件的极限承载力。试验结果表明,高强钢焊接箱形柱稳定系数采用GB 50017—2003《钢结构设计规范》中的c类截面柱子曲线偏保守,试验结果平均曲线更接近b类截面曲线,但仍需进一步验证。分析结果表明,考虑了初始缺陷的有限元模型可准确预测柱的极限承载力,可以作为试验数据的补充。

  10. Internal thermal origin mechanism of Karstic collapse column with no smoothly extrinsic cycle

    LI Yong-jun; PENG Su-ping; LI Pei-quan; LIU Deng-xian; LIAN Hui-qing


    Huainan coal field as main object, investigation of Karstic hydrogeological conditions were developed in Huainan structureal unit, and the basic conditions, features and rules of Karstic growth were summarized. Geology background and causes of Karstic collapse columns were analyzed. Combined with ancient physiognomy, environment and litho-facies features. After studying synthetically Karstic collapse columns, shape of collapse body, filling feature, hydrodynamic condition and agglutinate material in Huainan area, considering mine hydrogeological conditions of Xuhuai coal field and referenced Karstic collapse columns characters of other mines in North China, the internal thermal origin theory is elementarily formed for Karstic collapse columns extrinsic cycle can not operate smoothly. Finaly, three aspects including distributing features of different kinds of Karstic collapse columns in north China type coal field, conditions of Karstic collapse columns origined from internal thermal with no smoothly extrinsic cycle, mechanics of causes were analyzed and demonstrated.

  11. Experimental study on cleaning concentration of scheelite by flotation column%利用浮选柱进行自钨精选的

    辛亚淘; 邓双丽; 张兆金; 孔令同


    利用小型浮选柱进行白钨精选的探索试验,在粗精矿品位1.2%左右的情况下,获得了精矿品位41.25%、回收率81.24%的指标,与精选采用BF型浮选机的选厂相比,精矿品位提高近10%。%The exploratory experiment about cleaning concentration of scheelite by using small flotation column was carried out, and scheelite concentrates with grade of 41.25% and recovery rate of 81.24% was ob- tained from rough concentrate with grade of 1.2%. Concentrate grade was higher by 10% than the one produced from BF flotator.

  12. The CGILS experimental design to investigate low cloud feedbacks in general circulation models by using single-column and large-eddy simulation models

    Zhang, Minghua; Bretherton, Christopher S.; Blossey, Peter N.; Bony, Sandrine; Brient, Florent; Golaz, Jean-Christophe


    A surrogate climate change is designed to investigate low cloud feedbacks in the northeastern Pacific by using Single Column Models (SCMs), Cloud Resolving Models (CRMs), and Large Eddy Simulation models (LES), as part of the CGILS study (CFMIP-GASS Intercomparison of LES and SCM models). The constructed large-scale forcing fields, including subsidence and advective tendencies, and their perturbations in the warmer climate are shown to compare well with conditions in General Circulation Models (GCMs), but they are free from the impact of any GCM parameterizations. The forcing fields in the control climate are also shown to resemble the mean conditions in the ECMWF-Interim Reanalysis. Applications of the forcing fields in SCMs are presented. It is shown that the idealized design can offer considerable insight into the mechanisms of cloud feedbacks in the models. Caveats and advantages of the design are also discussed.

  13. Influence of tray hydraulics on tray column

    Betlem, Bernardus H.L.; Rijnsdorp, J.E.; Rijnsdorp, J.E.; Azink, R.F.


    To column control, in contrast to column design, tray hold-up and dependencies of tray hold-up on the operating conditions play an important role. The essence of this article is the development of an improved model of tray hydraulics over a broad operating range and its experimental validation by



    <正>20141574 Chen Hao(Exploration and Development Research Institute,Daqing Oilfield Company,Daqing 163712,China)High-Resolution Sequences and Coal Accumulating Laws in Nantun Formation of Huhe Lake Sag(Petroleum Geology&Oilfield Development in Daqing,ISSN1000-3754,CN23-1286/TQ,32(4),2013,p.15-19,5 illus.,15 refs.)Key words:coal accumulation regularity,coal



    <正>20091159 Gao Yan(No.3 Prospecting Team of Anhui Bureau of Coal Geology,Suzhou 234000,China) Effect of Depositional Environment of Coal-Bearing Stratum on Major Coal Seams in Suntan Coalmine,Anhui Province(Geology of Anhui,ISSN 1005- 6157,CN34-1111/P,18(2),2008,p.114 -117,5 illus.,1 ref.,with English abstract)

  16. Modeling Stone Columns

    Jorge Castro


    Full Text Available This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the “unit cell”, longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns.

  17. Modeling Stone Columns


    This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the “unit cell”, longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns. PMID:28773146

  18. Pelletization of fine coals. Final report

    Sastry, K.V.S.


    Coal is one of the most abundant energy resources in the US with nearly 800 million tons of it being mined annually. Process and environmental demands for low-ash, low-sulfur coals and economic constraints for high productivity are leading the coal industry to use such modern mining methods as longwall mining and such newer coal processing techniques as froth flotation, oil agglomeration, chemical cleaning and synthetic fuel production. All these processes are faced with one common problem area--fine coals. Dealing effectively with these fine coals during handling, storage, transportation, and/or processing continues to be a challenge facing the industry. Agglomeration by the unit operation of pelletization consists of tumbling moist fines in drums or discs. Past experimental work and limited commercial practice have shown that pelletization can alleviate the problems associated with fine coals. However, it was recognized that there exists a serious need for delineating the fundamental principles of fine coal pelletization. Accordingly, a research program has been carried involving four specific topics: (i) experimental investigation of coal pelletization kinetics, (ii) understanding the surface principles of coal pelletization, (iii) modeling of coal pelletization processes, and (iv) simulation of fine coal pelletization circuits. This report summarizes the major findings and provides relevant details of the research effort.

  19. The growth regularity and detective technique of collapse column

    Liu, Z. [Xingtai Coal Mining Bureau (China)


    The paper summarizes the growth regularity and the related factors of collapse column in Duongpang Coal Mine, introduces the applicability of roadway explorations, drillings and geophysical prospecting methods, expounds how to select an economic and quick exploration method according to the characteristics of each method and difference geological conditions for detecting the place, shape, size and water-bearing property of collapse column. 4 figs.

  20. Column Liquid Chromatography.

    Majors, Ronald E.; And Others


    Reviews literature covering developments of column liquid chromatography during 1982-83. Areas considered include: books and reviews; general theory; columns; instrumentation; detectors; automation and data handling; multidimensional chromatographic and column switching techniques; liquid-solid chromatography; normal bonded-phase, reversed-phase,…

  1. Electroosmotic Driving Liquid Using Nanosilica Packed Column

    Ling Xin CHEN; Guo An LUO; Tao WEN


    The electroosmotic pump (EOP) using nanosilica particles packed-bed column was experimentally studied. The relationship between flowrate, pressure and applied voltage of the pump, and pressure-flowrate (P-Q) characteristic were investigated.

  2. Simulation analysis on geological structure detection of collapse column in coal roadway excavation%煤巷掘进中陷落柱地质构造探测仿真及结果分析



    To detect the collapse column geological structure hidden behind the excavation face, dual-frequency induced polarization ahead-detecting technology ( DIPAT ) is applied, physical model of collapse column is built, which is simplified into equivalent circuit, according to the electrical parameters. The induced polarization model of collapse column is established based on Simulink, obtaining the resistivity and the PFE value curves. According to the consistency of the simulation detection results and the preinstalled parameters of the induced polarization model, the correctness of the simulation detection model is proved.%为了探测掘进面前方隐伏的陷落柱地质构造,采用双频激电法煤巷综掘超前探测技术,建立了陷落柱地质构造物理模型,根据其电性参数将物理模型简化为相应的等效电路,通过Simulink平台构建了陷落柱地质构造的激电模型并进行模拟测试,得出了该激电模型的视电阻率值和视频散率PFE值的变化曲线。仿真探测结果与激电模型预设的电性参数基本一致,验证了该仿真探测模型对陷落柱地质异常预报的有效性,为下一步开发该技术的配套探测仪器提供了必要的参考依据。



    <正>20131668 Chang Huizhen(Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process,CUMT,Ministry of Edu-cation,School of Resource and Earth Science,China University of Mining and Technology,Xuzhou 221008,China);Qin Yong Differences in of Pore Structure of Coals and Their Impact on the Permeability of Coals from the

  4. Hydrodynamics and Mass Transfer Performance in Supercritical Fluid Extraction Columns

    石冰洁; 张泽廷; 等


    New models for describing hydrodynamics and mass transfer performance in supercritical fluid extraction columns were proposed.Those models were proved by experimental data,which were obtained in supercritical fluid extraction packed column,spray column and sieve tray column respectively.The inner diameter of those columns areΦ25mm,These experimental systems include supercritical carbon dioxideisopropanol-water and supercritical carbon dioxide-ethanol-water,in which supercritical carbon dioxide was dispersed phase,and another was continuous phase.The extraction processes were operated with continuous countercurrent flow.The predicted values are agreed well with experimental data.

  5. 煤自燃倾向性鉴定实验方法探讨%Discussion on experimental method of coal spontaneous combustion tendency identiifcation

    张腾腾; 李丽; 张帅


    目前国内煤炭自燃分类等级的鉴定基础研究还较为片面,现有的煤自燃倾向性色谱吸氧法反映出煤表面对氧的物理吸附特性,煤自燃倾向性氧化动力学测定法反映煤氧化的内在动力学特性。为此,该论文对AQ/T 1068-2008《煤自燃倾向性的氧化动力学测定方法》[1]和GB/T 20104-2006《煤自燃倾向性色谱吸氧鉴定法》[2]进行了研究分析。%At present domestic coal spontaneous combustion classiifcation identiifcation of the basic research is still relatively one-sided, existing oxygen coal self-ignition orientation chromatographic method reflects the physical adsorption characteristics of coal surface to oxygen, coal spontaneous combustion propensity to oxidation kinetics measurement relfects the inherent dynamic characteristics of coal oxidation. To this end, the paper to AQ/T 1068-2008 the self-ignition orientation of coal oxidation kinetics determination method and GB/T 20104-2006 \\"oxygen coal self-ignition orientation chromatography assay method\\" are analyzed.

  6. 隔板塔气体调配装置数值模拟及实验研究%CFD simulation and experimental research on vapour splitter in divided wall column

    陈文义; 孙姣; 葛化强; 陈楠; 陈祥武


    针对隔板塔中隔板两侧气体分配比难以调节的问题,提出了一种新型隔板塔气体调配装置。利用计算流体力学软件 STAR-CCM+对该装置的性能进行了模拟分析,并经实验研究对模拟结果进行验证;对不同塔径下升气槽个数进行了模拟研究。结果表明:该气体调配装置能够有效地调节气体在隔板两侧的分配,并且气体通过该装置后分布较均匀,成功实现了气相在隔板塔内的分配控制,实验结果和模型模拟值符合良好。%In order to resolve the problem of controling the vapour split in the divided wall column (DWC), a new vapour splitter was put forward. The study was carried out by using the computational fluid dynamics (CFD) software STAR-CCM+ withk-ε turbulence model and SIMPLE method. The split and the nonuniformity of the vapour were researched and compared against experimental data. The relationship between vapour tubes and internal diameter of the column was examined by simulations. Model results and experimental data obtained in this study have revealed that the device can accurately adjust the vapour split and achieve a uniform vapour distribution. The model results were in good agreement with experimental data.


    薛志成; 姜博文; 张林; 裴强


    The modal analysis of a column-supported concrete bunker structure was carried out,the characteristics of the mode shapes and frequencies were obtained. At the same time, based on the soil-structure interaction,the time history analysis of earthquake response of the concrete bunker structure was also done; through the input of three kinds of earthquake waves (El Centro, Taft wave and artificial wave),a time history of the displacement of coal bunker structure node and its maximum displacement were got,and the weak parts of the structure were determined, which provided a reference to the seismic design and identification of such sort of coal bunker structure.%对柱承式混凝土煤仓结构进行模态分析,得到其振型和频率的特点。同时,基于土-结构相互作用,进行柱承式混凝土煤仓结构的地震反应时程分析,通过输入3种地震波( El Centro波、Taft波和人工波),分析得到不同工况下煤仓结构节点的位移时程和最大位移值,确定出结构的薄弱部位,为柱承式混凝土煤仓结构的抗震设计和鉴定提供参考。

  8. Dewatering studies of fine clean coal

    Parekh, B.K.


    The main objective of the present research program is to study and understand dewatering characteristics of ultrafine clean coal obtained using the advanced column flotation technique from the Kerr-McGee's Galatia preparation plant fine coal waste stream. It is also the objective of the research program to utilize the basic study results, i.e., surface chemical, particle shape particle size distribution, etc., in developing a cost-effective dewatering method. The ultimate objective is to develop process criteria to obtain a dewatered clean coal product containing less that 20 percent moisture, using the conventional vacuum dewatering equipment. (VC)

  9. Experimental Research on Seismic Behavior of Mega-Frame with Multi-Cell CFST Columns%多腔钢管混凝土柱巨型框架抗震性能试验研究

    彭斌; 曹万林; 王智慧; 董宏英; 张建伟


    The experimental research on seismic behavior of a 1/25 scaled mega-frame model with 3 mega-storey from the bottom has been carried out according to a supper high-rise mega-frame structure building. The multi-cell special-shaped CFST columns are used for mega-columns. The steel truss beams are used for mega-beams. The K-shaped steel brace with box section is set at the bottom mega-storey. The X-shaped steel braces with box section are set at the second and the third mega-storey. The hysteretic properties, load-bearing capacity , stiffness and its degeneration, ductility and yielding mechanism of the mega-frame have been analyzed based on the experiment. The results show that the brace in the mega-frame yields as the first line of defense. Then the upper and the lower chord members of mega truss beam yield. At last, the plastic hinges appear at the bottom of mega-column. The ductile yielding mechanism has been achieved for the multi-frame structure with multi-cell CFST columns with good seismic behavior.%结合某超高层巨型框架结构工程实际,进行了一榀巨型框架结构底部三个巨型层1/25缩尺模型抗震性能试验研究.该巨型框架的巨型柱为多腔钢管混凝土异形截面柱,巨型梁为钢桁架梁,底部巨型层加设人字形箱形截面钢支撑,二、三巨型层加设X形箱形截面钢支撑.通过试验,分析了该巨型框架的滞回特性、承载力、刚度及退化过程、延性和屈服机制.试验表明,该巨型框架的支撑作为第一道防线首先屈服,之后巨型桁架梁上下弦杆进入屈服,最后巨型柱柱底出现塑性铰,实现了多腔钢管混凝土柱巨型框架结构延性屈服机制,抗震性能良好.



    <正>20111053 Chen Jian(School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001,China);Liu Wenzhong Organic Affinity of Trace Elements in Coal from No.10 Coal-Bed at Western Huagou,Guoyang(Coal Geology & Exploration,ISSN1001-1986,CN61-1155/P,38(4),2010,p.16-20,24,3 illus.,3 tables,19 refs.)Key words:coal,minor elements,Anhui Province In order to study the organic affinity of trace elements in coal from No.10 coal-bed at western Huagou,Guoyang,10 borehole samples were collected at exploration area of Huaibei mining area.The contents of 12 kinds of trace elements were determined by the inductively coupled plasma mass spectrometry(ICP-MS),the total organic carbon(TOC)of coal was determined by LECO carbon and sulfur analyzer,and the organic affinity of trace elements were deduced from the correlations between contents and TOCs.The results showed that the contents of V,Cr,Co,Ni,Mo,Cd,Sb,Pb and Zn were lower than

  11. Experimental Study of Integrated Ebullated-bed and Fixed-bed for Hydrotreating Mid-Low Temperature Coal Tar to Clean Fuel

    Meng Zhaohui; Yang Tao; Fang Xiangchen


    A new hydrotreating technology integrating the ebullated-bed (EB) and the fixed-bed (FB) hydrogenation was proposed to investigate the efficiency for hydrotreating mid- low-temperature coal tar to clean fuel, and multiple tests at the bench scale were carried out. The results showed that the distillates obtained from EB reactors were greatly upgraded and could meet the requirements of FB unit without discarding any tail oil. The naphtha produced from FB reactors could be fed to the catalytic reforming unit, while a high quality diesel was also obtained. The unconverted oil (UCO) could be fur-ther hydrocracked to clean fuel. It is found that the removal of impurities from the coal tar oil is related with the molecular aggregation structure and composition of the coal tar. Application of the integrated hydrotreating technology to the high-temperature coal tar processing demonstrated that more than half of heavy components could be effectively upgraded.

  12. Beam Studies with Electron Columns

    Shiltsev, V.; Valishev, A.; Kuznetsov, G.; /Fermilab; Kamerdzhiev, V.; /Julich, Forschungszentrum; Romanov, A.; /Novosibirsk, IYF


    We report preliminary results of experimental studies of 'electron columns' in the Tevatron and in a specialized test setup. In the Tevatron, a beam of 150 GeV protons ionizes residual gas and ionization electrons are stored in an electrostatic trap immersed into strong longitudinal magnetic field. Shifts of proton betatron frequencies are observed. In the test setup, we observe effects pointing to accumulation and escape of ionization electrons.

  13. Major elements distribution during liquefaction of beneficated coal fractions from hydrocyclone and flotation

    Barraza, J. [Universitaria Melendez (Colombia). Dept. de Procesos Quimicos; Cloke, M.; Belghazi, A. [Nottingham Univ. (United Kingdom). Dept. of Chemical Engineering


    Beneficiated coal fractions obtained by hydrocyclone and column flotation separation were liquefied in order to determine their effect on the reduction of the major element content in the coal extract liquid prior to hydroprocessing. Results showed that some major elements, mainly Ca, Mn and Ti, were reduced using these beneficiated coal fractions. In general, all the elements exhibit higher reduction using overflow from the cyclone separation compared to the concentrate from the column flotation. (orig.)

  14. 新疆阜康矿区煤层孔隙结构特征的氮吸附实验研究%Nitrogen adsorption experimental study on pore structure characteristics of coal seams in Xinjiang Fukang mining area

    林海飞; 程博; 李树刚; 曾强; 张雪涛; 成连华


    为研究新疆阜康矿区主采煤层吸附孔孔隙结构特征,选取该矿区四个典型煤样,基于低温氮吸附实验绘制了煤样的吸附解吸等温线,得到煤的孔隙直径,采用BET模型和BJH模型计算了孔隙比表面积和体积等参数,分析了煤样孔隙比表面积及体积分布规律.结果表明:新疆阜康矿区煤的吸附解吸等温线回滞环很小,吸附孔以一段开口的均匀圆筒形孔为主.煤样吸附孔发育程度差别明显,导致各煤层对瓦斯吸附储存能力有所不同.各煤样孔径分布较为均衡,比表面积以过渡孔占比最大,其次为微孔及中孔;过渡孔和中孔的孔隙体积占比较大,微孔较小.煤样孔隙体积分布规律基本一致,比表面积在过渡孔和中孔范围内分布规律相同,微孔范围内分布差异较大.%To study the adsorption pore structure characteristics of main coal seam in Xinjiang Fukang mining area,four typical coal samples were selected in this mining area. Based on the experimental re-sults of low temperature nitrogen adsorption,the adsorption and desorption isotherms of coal samples were drawn,and the pore diameter is obtained. Using the BET theory and BJH theory,pore specific surface area and volume of coal samples are calculated. The distributions of pore specific surface and volume of coal samples were analyzed. The experimental results show that the adsorption and desorption isotherms of coal in Fukang mining area have very small hysteresis loop ,and most of the pores are cylin-drical with one end open. The difference of adsorption pore development degree of coal sample is obvi-ous,which causes different storage capacity of gas adsorption of coal seam. The average pore sizes of each coal sample are approximately the same. The specific surface area of transition pores accounted for the largest surface area of adsorption pore ,followed by micropore and mesopore;the volume of transition pore and mesopore accounted for the largest

  15. Experimental study on modified recycled aggregate concrete-filled steel tube columns under axial compression%改性钢管全再生粗骨料混凝土短柱的轴压试验

    陈娟; 许成祥; 邓曦


    In order to make full use of recycled aggregate, 20 specimens with circular and square cross sections were designed to be tested, and the dosage of silica powder and content of steel fiber were regarded as the major variable parameters. Through the experiment, the entire compress process and failure modes of all specimens were observed, and load-strain curves of the specimens were obtained. The test results indicate that the ultimate axial load and corresponding strain of the concrete-filled steel tube columns would decrease after the replacement of natural coarse aggregate with 100% recycled coarse aggregate. The filling effect and pozzolanic action of silica powder and the confinement effect of steel fiber could be used to improve the performance of concrete-filled steel tube columns with 100% recycled coarse aggregate, and the performance of modified columns was i- dentical to that of common columns. The column with 10% cement replaced by silica powder and 1. 5%volume fraction of steel fiber has a higher ultimate axial load than that of common columns. In addition, the applicability of present theory and formula from different codes to calculate the bearing capacity of the specimens was obtained based on the comparison of calculated results. The results obtained by EC4 are more close to the experimental results.%为了最大化利用再生骨料,以硅粉和钢纤维掺量为主要变化参数设计了20个圆形和方形截面钢管全再生粗骨料混凝土短柱构件进行轴压试验,观察了短柱的受力全过程和破坏形态,获取了构件的荷载―变形全过程曲线,分析了硅粉和钢纤维掺量对其承载性能的影响,试验结果表明:混凝土中的粗骨料全部采用再生骨料会降低钢管再生混凝土柱的峰值承载力及峰值应变,可以采用硅粉的填充效应及活性和钢纤维对裂缝的内部约束来改善钢管全再生骨料混凝土柱的性能,经改性后的钢管全再生骨料混

  16. Ukrainian experience of oil agglomeration of coals

    Biletskyi, V.S. [Donetsk State Technical University, Donetsk (Ukraine). Dept. of Coal Preparation


    During the years 1980-1996 a series of investigations related to the applied and theoretical aspects of the coal oil agglomeration processing were carried out in the Ukraine at the Donetsk State Technical University and Coal Chemistry National Academy of Sciences (NAN) of Ukraine, institutes UralVTI, VNIIPIHidrotruboprovod, LenNIlkhimmash, Kharkiv polytechnical Institute, Institute of Biocolloide Chemistry NAN of Ukraine and also at coal preparation plants and thermoelectric power stations in the Donbas. Theoretical bases of the process of selective oil agglomeration are developed on the basis of modern physical chemistry, physical-chemical hydrodynamics, adhesion theory, and solid fuel chemistry. The necessary sufficient conditions for aggregate forming coal and oil components in water have been formulated. The central problem of `coal-reagent` interaction during coal aggregation has been solved, and a mathematical description of processes for forming coal-oil aggregates including kinetics has been made. Analysis of factors which influence the process and its mathematical models have been realized. Rational conditions of pelletising of energetic and coking coal, coal raw material and products of coal preparation plants, electric power stations, and hydrotransport systems have been determined. Results of the complex study of technological properties of coal aggregates as objects of dewatering, hydrotransportation, consumption, coking, pyrolysis and carriers at gold adhesive preparation are presented. The theoretical principles and experimental data served as a basis for creating about 40 new methods and devices for the process of coal selective oil agglomeration. 14 refs., 7 figs., 1 tab.

  17. Behavior of high strength concrete columns under eccentric loads

    Hany A. Kottb


    Full Text Available In recent decades, high strength concrete (HSC has been widely accepted by designers and contractors to be used in concrete structures, especially in high compressive stress elements. The research aims to study the behavior of high strength concrete columns under eccentric compression using experimental and analytical programs. The research is divided into two main parts; the first part is an experimental investigation for ten square columns tested at the Cairo University Concrete Research Laboratory. The main studied parameters were eccentricity of the applied load, column slenderness ratio; and ratios of longitudinal and transverse reinforcement. The second part is analytical analysis using nonlinear finite element program ANSYS11 on nineteen columns (ten tested square columns and nine rectangular section columns to study the effect of the previous parameters on the column ultimate load, mid-height displacement, and column cracking patterns. The analyzed columns revealed a good agreement with the experimental results with an average difference of 16% and 17% for column ultimate load and mid-height displacement respectively. Results showed an excellent agreement for cracking patterns. Predictions of columns capacities using the interaction diagrams based on ACI 318-08 stress block parameters indicated a safe design procedure of HSC columns under eccentric compression, with ACI 318-08 being more conservative for moderate reinforced HSC columns.

  18. Experimental Investigation into Axial Compressive Behavior of Cold Formed Thin-Walled Steel Columns with Lipped Channel and Openings%开孔冷弯薄壁卷边槽钢柱轴压性能的试验研究

    姚永红; 武振宇; 成博; 邓君宝


    为研究腹板开孔具中间加劲肋的冷弯薄壁卷边槽钢构件的受压性能,对两种截面形式的短柱和中长柱共计16根轴压构件的承载力和屈曲模式进行了试验分析.结果表明:所有试件均发生畸变屈曲失效,中长柱试件还伴随有绕弱轴的整体弯曲;腹板孔洞导致构件屈曲模式发生变化,孔洞周边板件有局部屈曲产生;孔洞的存在使试件承载力降低,短柱试件承载力的减小幅度比中长柱试件的大;同组试件中畸变初始缺陷大的,一般承载力较小,畸变变形偏大;极限承载力下开孔构件的畸变变形一般大于未开孔构件.文中还对所有试件进行了有限元模拟,发现有限元分析结果与试验值吻合较好.%In order to investigate the compression behavior of the cold-formed thin-walled steel columns with lipped channel, intermediate stiffener and openings in the web, 16 axial compressive members, including the short and the medium-length columns in two section forms, were experimentally analyzed in the aspects of bearing capacity and buckling mode. The results show that all of the specimens fail due to the distortional buckling and the medium-length columns have additional overall bending around the weak axis, that the openings in the web result in the changes of buckling modes of the members and the local bucklings of the plates occur around the openings, and that, due to the effects of the openings, the bearing capacities of the specimens decrease and the decrement of the bearing capacity of the short column is greater than that of the medium-length one. Moreover, it is found that, for the specimens in the same test group, the columns with larger initial distortional imperfections are of lower bearing capacities and greater deformations induced by the distortional bucklings, and that the openings generally enhance the deformations corresponding to the ultimate bearing capacity. In addition, all of the tested specimens

  19. Experimental Study on Response Features of Acoustic Emission to Coal Samples During Loading Process%煤样加载过程声发射响应特征试验研究

    贾炳; 倪小明; 苏承东


    In order to research the response rule of acoustic emission about coal and rock with different fissures and heterogeneity in the loading process,original permeability and acoustic emission parameters in the loading process about the coal samples with different fissures and heterogeneity in Sihe Coal Mine were tested by the RMT-150B rock mechanics test system and acoustic emission system. The results showed that acoustic emission energy increased quickly to maximum in the late stage of plastic deformation or in the early stage of elastic deformation when the fractures of coal samples were uniform,then the energy decreased slightly and maintained at a level. Acoustic emission energy was high at the beginning of the elastic deformation,then the energy increased to the maximum,finally the energy maintained at a certain value when the fractures of coal samples were non-uniform and developed.The experimental results had a good prediction on the deformation of coal and rock in the process of coal mining.%为了探究不同裂隙发育程度、分布非均匀程度的煤样在加载过程中声发射响应规律,利用RMT-150B岩石力学伺服试验系统和声发射监测系统对寺河矿不同裂隙发育程度、分布非均匀程度的煤样进行原始渗透率和加载过程中声发射参数测试。结果表明:裂隙分布较均匀的煤样加载时,声发射能量在塑性变形阶段前期或弹性变形阶段后期快速增至最大值,后略有减小并维持在一定水平;裂隙分布非均匀性强且裂隙发育的煤样加载时,声发射能量在弹性变形初期就达较高值,后逐渐增加至最大值,随后稳定在一定值。试验结果对采煤过程中煤岩变形规律具有较好的预测作用。

  20. Spiral multicapillary columns

    Efimenko, A. P.; Naumenko, I. I.; Soboleva, V. K.


    It was shown in a theoretical study and confirmed by experiment that a spiral multicapillary column had maximum efficiency if the bunch of capillaries was additionally coiled around its longitudinal axis to produce an integral number of coils. This technique made it possible to manufacture gas-chromatographic columns with performance as high as 12 to 16 thousand theoretical plates. These columns can find various applications, especially if quick separation is required.

  1. British coal

    Forrest, M.


    The paper describes a visit to UK's Daw Mill in north Warwickshire to find out about a planned expansion of the coal mine. Daw Mill, 10 km west of Coventry is the UK's largest underground coal mine. The coal is extracted by an Eckhoff Sl500 coal shearer that traverses the coalface. Overarching the shearer is a series of electro-hydraulically operated powered roof supports (PRS) over the roof and coalface that are advanced forward after each pass of the shearer. The void behind the PRS is then allowed to collapse. The coalface is currently 295 m long, but there are plans to extend the replacement coalface to 357 m. Under the shearer is an armored face conveyor (AFC) that receives and transports the coal along the coalface and deposits it onto the beam stage loader, which sits at 90{sup o} to the AFC. The coal is turned by a deflector plough on the AFC headframe and is transferred to the belt conveyor to begin its journey out of the mine. Last year two significant records were broken at Daw Mill - the fastest million tonnes achieved and the European record for a single face of 3.2 Mt. The 300s area of the mine has already been mapped out and development teams are constructing roadways to facilitate more mining. To maintain annual production in excess of three million tonnes will require at least 5,000 m of roadways to access the coal, and install equipment. These investments are supported by proven reserves. Seismic surveys and borehole drilling has shown approximately 20 Mt of extractable coal in the 300s area which extends over 15 km{sup 2}. These panels will be the next to be mined in a sequence that extends to 2014. 2 photos.

  2. Coal mining: coal in Spain

    Garcia-Arguelles Martinez, A.; Lugue Cabal, V.


    The Survey of Spanish Coal Resources published by the Centre for Energy Studies in 1979 is without doubt the most serious and full study on this subject. The coal boom of the last few years and the important role it will play in the future, as well as the wealth of new information which has come to light in the research carried out in Spanish coalfields by both the public and private sector, prompted the General Mine Management of the Ministry of Industry and Energy to commission IGME to review and update the previous Survey of Spanish Coal Resources of November 1981.

  3. Transformation of coals at the heat treatment

    S.A. Aipshtein; V.I. Minaev; O.V. Barabanova; V.A. Novikova [Moscow State University of Mining (MSMU), Moscow (Russian Federation)


    The coals (from Kuznetsk and Donetsk basins) were selected with the following criteria: a) different rank; b) different genetic types. The substantial and chemical compositions of the coals were determined. Experimental works on coal heat treatment were carried out at temperatures 423K, 473K, 523K, 573K and different times of processing in the conditions excluding oxidation of coals. It was shown, that the prevailing contribution of destruction or cross-linking in the general process of coal transformation at the heat treatment depends on temperature and time of thermal treatment. It was shown that the depth and direction of coals transformations at the heat treatment essentially depended on the genetic type of coals. 7 refs., 3 figs., 1 tab.

  4. Numerical Simulations of Settlement of Jet Grouting Columns

    Juzwa Anna


    Full Text Available The paper presents the comparison of results of numerical analyses of interaction between group of jet grouting columns and subsoil. The analyses were conducted for single column and groups of three, seven and nine columns. The simulations are based on experimental research in real scale which were carried out by authors. The final goal for the research is an estimation of an influence of interaction between columns working in a group.

  5. Anchoring FRP laminates for the seismic strengthening of RC columns

    Sadone, Raphaëlle; Quiertant, Marc; FERRIER, Emmanuel; Chataigner, Sylvain; Mercier, Julien


    This paper aims to examine the effectiveness of seismic strengthening of reinforced concrete (RC) columns by externally bonded Fibre Reinforced Polymer (FRP). Particularly, a novel strengthening system, designed for the flexural strengthening of columns is studied. This flexural strengthening is achieved by FRP plates bonded longitudinally and anchored at the column-stub junction. The proposed system is validated through an experimental campaign carried out on full-scale RC columns. Different...

  6. Blended coals for improved coal water slurries

    GU Tian-ye; WU Guo-guang; LI Qi-hui; SUN Zhi-qiang; ZENG Fang; WANG Guang-you; MENG Xian-liang


    Three coal samples of different ranks were used to study the effect of coal blending on the preparation of Coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentration in slurry made from hard-to-pulp coal can be effectively improved and increased by 3%-5% generally. DLT coal (DaLiuTa coal mine) is very poor in slurryability and the stability and rheology of the resulting slurry are not very good. When the amount of easily slurried coal is more than 30%, all properties of the CWS improve and the CWS meets the requirements for use as fuel. Coalification, porosity, surface oxygenic functional groups, zeta potential and grindability have a great effect on the performance of blended coal CWS. This leads to some differences in performance between the slurry made from a single coal and slurry made from blended coal.

  7. Pulverized-coal-firing small-size boiler for coal-cartridge system


    Kawasaki Heavy Industries, Ltd. supplied a test boiler plant to the Iwakuni Experimental Station of the Coal Cartridge System (CCS) Promotion Association in September 1985; this was the first pulverized-coal-fired small industrial boiler in Japan. Tests will be performed for two years, until fiscal 1987, at the CCS Iwakuni Experimental Station to establish a method of coal-firing with a performance comparable to heavy oil firing. The boiler plant has been operating satisfactorily.

  8. 热成型不锈钢圆管混凝土轴压短柱受力性能试验研究%Experimental study on axial compressive behavior of concrete-filled thermoforming stainless steel tubular stub columns

    陈誉; 李凤霞; 王江


    This paper presents an experimental study on axial compressive behavior of concrete-filled thermoforming stainless steel tubular ( CFTSST) stub columns. Seventeen specimens of CFTSST stub columns with different parameters were tested under axial compression. The parameters in the study included the compressive strength of concrete ( C30 and C40) ,wall thickness of thermoforming stainless steel t (0. 9 mm,l. 0 mm,l. 2 mm) and height-diameter ratio of specimens A (3.0, 3.5 and 4.0). This paper presents test procedure, specimens failure phenomena, load-axial displacement curves, load-circular strain curves and load-axial strain curves. Based on the failure phenomena, all specimens were divided into 5 failure modes. The effects of t and A on compressive ultimate capacity, ductility and stiffness were investigated. The results of tests show that the stress of specimens increases greatly at the end of the yield stage; as value of t increases, compressive ultimate capacity, ductility and stiffness of specimens increase; as value of A increases, ductility increases, stiffness decreases; the value of compressive ultimate capacity gets maximum when the value of λ is 3. 5, it is lower when A is 4. 0,gets minimum when A is 3. 0; according to the comparisons between CFTSS tubular stub columns and concrete-filled steel tubular stub columns, the results show that the restraint amplification coefficient of CFTSS tubular stub columns is higher.%对热成型不锈钢圆管混凝土短柱在轴向压力作用下的承载性能进行试验研究,试验主要参数为混凝土强度(C30和C40)、不锈钢管壁厚t(0.9 mm、1.0 mm和1.2mm)和试件的高径比λ(3.0、3.5、4.0),试验观测了不锈钢圆管混凝土短柱在轴向压力作用下的破坏现象、试件荷载-轴向变形曲线、荷载-环向应变曲线、荷载-轴向应变曲线等.根据试验的破坏现象,将试件分为5种破坏模式,并分析了不锈钢管壁厚t和试件的高径比λ对试件的承载

  9. Novel Fuel Cells for Coal Based Systems

    Thomas Tao


    The goal of this project was to acquire experimental data required to assess the feasibility of a Direct Coal power plant based upon an Electrochemical Looping (ECL) of Liquid Tin Anode Solid Oxide Fuel Cell (LTA-SOFC). The objective of Phase 1 was to experimentally characterize the interaction between the tin anode, coal fuel and cell component electrolyte, the fate of coal contaminants in a molten tin reactor (via chemistry) and their impact upon the YSZ electrolyte (via electrochemistry). The results of this work will provided the basis for further study in Phase 2. The objective of Phase 2 was to extend the study of coal impurities impact on fuel cell components other than electrolyte, more specifically to the anode current collector which is made of an electrically conducting ceramic jacket and broad based coal tin reduction. This work provided a basic proof-of-concept feasibility demonstration of the direct coal concept.

  10. Flow in Coal Seams: An Unconventional Challenge

    Armstrong, R. T.; Mostaghimi, P.; Jing, Y.; Gerami, A.


    A significant unconventional resource for energy is the methane gas stored in shallow coal beds, known as coal seam gas. An integrated imaging and modelling framework is developed for analysing petrophysical behaviour of coals. X-ray micro-computed tomography (micro-CT) is applied using a novel contrast agent method for visualising micrometer-sized fractures in coal. The technique allows for the visualisation of coal features not visible with conventional imaging methods. A Late Permian medium volatile bituminous coal from Moura Coal Mine (Queensland, Australia) is imaged and the resulting three-dimensional coal fracture system is extracted for fluid flow simulations. The results demonstrate a direct relationship between coal lithotype and permeability. Scanning electron microscope and energy dispersive spectrometry (SEM-EDS) together with X-ray diffraction (XRD) methods are used for identifying mineral matters at high resolution. SEM high-resolution images are also used to calibrate the micro-CT images and measure the exact aperture size of fractures. This leads to a more accurate estimation of permeability using micro-CT images. To study the significance of geometry and topology of the fracture system, a fracture reconstruction method based on statistical properties of coal is also developed. The network properties including the frequency, aperture size distribution, length, and spacing of the imaged coal fracture system. This allows for a sensitivity analysis on the effects that coal fracture topology and geometry has on coal petrophysical properties. Furthermore, we generate microfluidic chips based on coal fracture observations. The chip is used for flow experiments to visualise multi-fluid processes and measure recovery of gas. A combined numerical and experimental approach is applied to obtain relative permeability curves for different regions of interest. A number of challenges associated with coal samples are discussed and insights are provided for better

  11. Chemical Fixation of CO2 in Coal Combustion Products and Recycling through Biosystems

    C. Henry Copeland; Paul Pier; Samantha Whitehead; David Behel


    This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented.

  12. Chemical Fixation of CO2 in Coal Combustion Products and Recycling through Biosystems

    C. Henry Copeland; Paul Pier; Samantha Whitehead; David Behel


    This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented.

  13. Studies and research concerning BNFP pilot-scale pulsed columns: column profile and holdup studies

    Cermak, A. F.


    Experimental studies were conducted on pilot-scaled pulsed columns for the purpose of obtaining data for verification of contactor computer programs. This work is in support of safeguards programs related to determination of near real-time inventories in pulsed columns. Holdup tests were performed resulting in the derivation of an empirical equation for estimation of the dispersed phase holdup in a column. Uranium solvent extraction mass-transfer tests were conducted in which all four process cycles were simulated under coprocessing flowsheet conditions. Extensive data were obtained during these tests on uranium profiles and inventories within the columns. Transient profile data were also determined between selected runs under the tested operating conditions. No concentration peaks could be observed during the transient period. Based on the extensive inventory data taken, empirical equations were developed for relating uranium inventory in a column to the test parameters. These equations were found useful for predicting and estimating the column inventory under the known run conditions.

  14. JCE Feature Columns

    Holmes, Jon L.


    The Features area of JCE Online is now readily accessible through a single click from our home page. In the Features area each column is linked to its own home page. These column home pages also have links to them from the online Journal Table of Contents pages or from any article published as part of that feature column. Using these links you can easily find abstracts of additional articles that are related by topic. Of course, JCE Online+ subscribers are then just one click away from the entire article. Finding related articles is easy because each feature column "site" contains links to the online abstracts of all the articles that have appeared in the column. In addition, you can find the mission statement for the column and the email link to the column editor that I mentioned above. At the discretion of its editor, a feature column site may contain additional resources. As an example, the Chemical Information Instructor column edited by Arleen Somerville will have a periodically updated bibliography of resources for teaching and using chemical information. Due to the increase in the number of these resources available on the WWW, it only makes sense to publish this information online so that you can get to these resources with a simple click of the mouse. We expect that there will soon be additional information and resources at several other feature column sites. Following in the footsteps of the Chemical Information Instructor, up-to-date bibliographies and links to related online resources can be made available. We hope to extend the online component of our feature columns with moderated online discussion forums. If you have a suggestion for an online resource you would like to see included, let the feature editor or JCE Online ( know about it. JCE Internet Features JCE Internet also has several feature columns: Chemical Education Resource Shelf, Conceptual Questions and Challenge Problems, Equipment Buyers Guide, Hal's Picks, Mathcad

  15. Glass-silicon column

    Yu, Conrad M.


    A glass-silicon column that can operate in temperature variations between room temperature and about C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  16. Rational design method for mixed structure with steel beams and reinforced concrete column. Part 1. Experimental study on beam-column joint; Hashira RC hari S kongo kozo no goriteki sekkeiho ni kansuru kenkyu. 1. Hari kantsu keishiki no setsugobu jikken

    Takami, S.; Masuda, Y.; Yoshioka, K. [Obayashi Corp., Tokyo (Japan)


    Mixed structural systems of steel beams and a reinforced concrete column have been used in practical application. Several joint types have been developed, one of which is the standard steel beams passing through a reinforced concrete column. Local compressive failure (bearing failure) often occurs in this type of joint. A loading test was carried out on a beam-column joint to develop methods for reinforcing the bending strength of columns. The results are summarized as follows; (1) Bearing behavior can be improved by constructing Pre-Columns. (2) Maximum load can be increased and ductility can be improved by covering the top and bottom of columns with steel plates. 2 refs., 6 figs., 4 tabs.

  17. Reactivity of North Bohemian coals in coprocessing of coal/oil mixtures

    Sebor, G.; Cerny, J.; Maxa, D.; Blazek, J. [Inst. of Chemical Technology, Prague (Czechoslovakia); Sykorova, I. [Inst. of Rock Structure and Mechanics, Prague (Czechoslovakia)


    Autoclave experiments with North Bohemian coal were done in order to evaluate their reactivity in coprocessing with petroleum vacuum residue, Selected coals were comprehensively characterized by using a number of analytical methods. While the coals were of similar geological origin, some of their characteristics differed largely from one coal to another. Despite the differences in physical and chemical structure, the coals provided very similar yields of desired reaction products. The yields of a heavy non- distillable fraction and/or an insoluble solid residue were, under experimental conditions, largely affected by retrogressive reactions (coking). The insoluble solid fractions were examined microscopically under polarized light.

  18. Experimental Study on Seismic Performance of Steel -reinforced Ultra-high-strength Concrete Column%钢骨超高强混凝土柱抗震性能试验研究

    郑林; 贾金青; 朱伟庆; 叶浩


    为研究钢骨超高强混凝土柱的抗震性能,对6根钢骨超高强混凝土柱(λ=2.6)在低周反复荷载下进行试验,并且分析了试件的破坏过程和破坏方式,以及轴压比、配箍率及型钢形式对延性的影响。试验结果表明:钢骨超高强混凝土柱主要破坏形态为弯曲破坏和弯剪破坏,发生弯曲破坏的试件荷载-位移滞回曲线饱满,下降段较为平缓,表现出良好的抗震性能,发生弯剪破坏的试件荷载-位移滞回曲线狭窄,下降迅速,抗震性能较差;配箍率高、轴压比小、配置 H 型钢试件抗震性能好。%To study the seismic performance of steel-reinforced ultra-high-strength concrete columns ,the test research of 6 steel-reinforced ultra-high-strength concrete columns (λ = 2 .6) subjected to low-cyclic repetitional loads was carried out .Then ,the specimens’ failure process and modes as well as the effects of the axial compression ratio ,reinforcement ratio and section steel shape on the ductility of the steel-reinforced ultra-high-strength concrete columns were discussed . The experimental results show that the main failure patterns of the specimens are bending failure and shear failure .The hysteretic curves of bending failure specimens are plump with relatively slow descending branches ,showing excellent seis-mic behavior .However ,the hysteretic curves of shear failure specimens are slim with relatively quick descending branch -es ,showing bad seismic behavior .The specimens with the high reinforcement ratio ,high axial compression ratio and H-shaped section steel show excellent seismic behavior .


    刘祖强; 薛建阳; 赵鸿铁; 高亮


    Based on the experimental study on a lattice steel reinforced concrete frame with special -shaped columns under low cyclic reversed loading , the mechanical process and failure patterns were observed .The load-displacement hysteretic loops and skeleton curves and the load and displacement at different stages were obtained .The seismic behaviors such as inter-story drift ratio, ductility, energy dissipation and stiffness degradation were analyzed .Test results show that the failure mechanism of the structure is the beam-hinged mechanism , and it is a typical strong-column and weak-beam structure .The hysteretic loops are plump , and the stiffness degradation is unconspicuous . The ultimate elastic-plastic story drift rotation is larger than the limit value specified by the code , demonstrating the high capacity of collapse resistance .The ductility and energy dissipation of the structure are better than that of the reinforced concrete frame with special-shaped columns .%通过对空腹式型钢混凝土( SRC)异形柱框架进行低周反复加载试验,观察结构的受力过程和破坏形态,获得结构的荷载-位移滞回曲线和骨架曲线以及主要阶段的荷载和位移值,并分析结构的层间位移角、延性、耗能性能及刚度退化等抗震性能指标。试验结果表明:空腹式SRC异形柱框架破坏时形成梁铰机制,属于“强柱弱梁”型结构;滞回曲线较为饱满,刚度退化小;弹塑性极限层间位移角超过规范规定的限值,抗倒塌能力强;延性和耗能能力均优于钢筋混凝土异形柱框架。


    Kyriacos Zygourakis


    We report the development of a novel experimental technique that combines video microscopy and thermogravimetric analysis to optimize the detection of coal and char particle ignitions. This technique is particularly effective for detecting ignitions occurring in coal or char samples containing multiple particles, where other commonly used techniques fail. The new approach also allows for visualization of ignition mechanism. Devolatilized char particles appear to ignite heterogeneously, while coal particles may ignite homogeneously, heterogeneously or through a combination of both mechanisms.

  1. Advanced froth flotation techniques for fine coal cleaning

    Yoon, R.H.; Luttrell, G.H. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)


    Advanced column flotation cells offer many potential advantages for the treatment of fine coal. The most important of these is the ability to achieve high separation efficiencies using only a single stage of processing. Unfortunately, industrial flotation columns often suffer from poor recovery, low throughput and high maintenance requirements as compared to mechanically-agitated conventional cells. These problems can usually be attributed to poorly-designed air sparging systems. This article examines the problems of air sparging in greater detail and offers useful guidelines for designing bubble generators for industrial flotation columns. The application of these principles in the design of a successful advanced fine coal flotation circuit is also presented.

  2. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    Smit, F.J.; Jha, M.C.; Phillips, D.I.; Yoon, R.H.


    The goal of this project is engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. Its scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by design and construction of a 2 t/h process development unit (PDU). Large lots of clean coal are to be produced in the PDU from three project coals. Investigation of the near-term applicability of the two advanced fine coal cleaning processes in an existing coal preparation plant is another goal of the project and is the subject of this report.

  3. Environmental impact assessment and selenium transformation in coal mine spoils. Seventh quarterly report

    Atalay, A.; Koll, K.J.


    This quarterly report addresses the continued field investigation of a selected coal mining site in Oklahoma. Table 1 (appendix) portrays all the data (field measurements) taken at the Henryetta experimental site. An analysis of this data would be useful in providing information for potential Se migration from a coal mining site and the distribution of Se in a soil profile of land reclaimed to its pristine state. Also addressed is the methodology developed (1) for SeO{sub 4}{sup 2{minus}} and SeO{sub 3}{sup 2{minus}} adsorption on selected soils, (2) leachate migration through a cell column using soil samples from the Henryetta reclamation site, and (3) chemical transformation of SeO{sub 4}{sup 2{minus}} under harsh chemical and conditions.

  4. Mechanisms and kinetics of coal hydrogenation

    Baldwin, R M; Furlong, M W


    Colorado School of Mines is engaged in an experimental program to develop comprehensive models for the effects of coal composition upon the kinetics and mechanisms of coal hydrogenation, for the effects of mineral matter additives (disposable catalysts) upon kinetics and mechanisms of coal hydrogenation, and for the kinetics and mechanisms of the hydrogenation of coal derived products such as preasphaltenes, and asphaltenes. Experimental work was completed on a suite of bituminous coals, thus completing the initial phase of the coal reactivity study. Eleven of the 14 coals of the suite were successfully run in duplicate. Conversion to THF solubles was correlated well by pseudo-second order kinetics. The resulting kinetic rate constants correlated with H/C ratio, mean-max vitrinite reflectance, and a specially-defined fraction of reactive macerals. The data did not correlate well with O/C ratios of the parent coals. Computer-derived statistical fits of various kinetic models were limited in their effectiveness at fitting the experimental data. Experimental work on the first phase of the disposal catalyst studies was completed. Statistical significance testing of the experimental data showed: fractional conversion and yield of light hydrocarbon products increased with time; and mineral properties of the additives were more significant in increasing overall conversion than the additive surface areas. The relative effects of the additives are given.

  5. Controlling air toxics through advanced coal preparation

    Straszheim, W.E.; Buttermore, W.H.; Pollard, J.L. [Iowa State Univ., Ames, IA (United States)


    This project involves the assessment of advanced coal preparation methods for removing trace elements from coal to reduce the potential for air toxic emissions upon combustion. Scanning electron microscopy-based automated image analysis (SEM-AIA) and advanced washability analyses are being applied with state-of-the-art analytical procedures to predict the removal of elements of concern by advanced column flotation and to confirm the effectiveness of preparation on the quality of quantity of clean coal produced. Specific objectives are to maintain an acceptable recovery of combustible product, while improving the rejection of mineral-associated trace elements. Current work has focused on determining conditions for controlling column flotation system across its operating range and on selection and analysis of samples for determining trace element cleanability.

  6. Kinetics of coal pyrolysis

    Seery, D.J.; Freihaut, J.D.; Proscia, W.M. (United Technologies Research Center, East Hartford, CT (USA)); Howard, J.B.; Peters, W.; Hsu, J.; Hajaligol, M.; Sarofim, A. (Massachusetts Inst. of Tech., Cambridge, MA (USA)); Jenkins, R.; Mallin, J.; Espindola-Merin, B. (Pennsylvania State Univ., University Park, PA (USA)); Essenhigh, R.; Misra, M.K. (Ohio State Univ., Columbus, OH (USA))


    This report contains results of a coordinated, multi-laboratory investigation of coal devolatilization. Data is reported pertaining to the devolatilization for bituminous coals over three orders of magnitude in apparent heating rate (100 to 100,000 + {degree}C/sec), over two orders of magnitude in particle size (20 to 700 microns), final particle temperatures from 400 to 1600{degree}C, heat transfer modes ranging from convection to radiative, ambient pressure ranging from near vacuum to one atmosphere pressure. The heat transfer characteristics of the reactors are reported in detail. It is assumed the experimental results are to form the basis of a devolatilization data base. Empirical rate expressions are developed for each phase of devolatilization which, when coupled to an awareness of the heat transfer rate potential of a particular devolatilization reactor, indicate the kinetics emphasized by a particular system reactor plus coal sample. The analysis indicates the particular phase of devolatilization that will be emphasized by a particular reactor type and, thereby, the kinetic expressions appropriate to that devolatilization system. Engineering rate expressions are developed from the empirical rate expressions in the context of a fundamental understanding of coal devolatilization developed in the course of the investigation. 164 refs., 223 figs., 44 tabs.

  7. Distillation Column Flooding Predictor

    George E. Dzyacky


    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid



    <正>20091749 Cai Hou’an(College of Energy Geology,China University of Geosciences,Beijing 100083,China);Xu Debin SHRIMP U-Pb Isotope Age of Volcanic Rocks Distributed in the Badaohao Area,Liaoning Province and Its Significance(Coal Geology & Exploration,ISSN1001-1986,CN61-1155/P,36(4),2008,p.17-20,2 illus.,1 table,16 refs.)Key words:coal measures,volcanic rocks,U-Pb dating,LiaoningA set of andesite volcanic rocks distributes in the Badaohao area in Heishan County,Liaoning Province.It’s geological age and stratigraphy sequence relationship between the Lower Cretaceous Badaohao Formation and the volcanic rocks can not make sure till now and is influencing the further prospect for coals.Zircon

  9. A Novel Method for Borehole Blockage Removal and Experimental Study on a Hydraulic Self-Propelled Nozzle in Underground Coal Mines

    Zhaolong Ge


    Full Text Available When coal bed methane (CBM drainage boreholes cross fractured, soft, or water-swelling strata, they collapse and block frequently. Borehole blockages result in a rapid decrease in CBM extraction ability, which leads to a reduction in CBM output and threatens coal mine safety production. To solve these problems, a novel method that uses a self-propelled water-jet nozzle to dredge blocked boreholes in coal seams has been proposed on the basis of the existing technology. Based on a theoretical analysis of the reason for borehole caving and the theory of blockage removal, we optimized the nozzle inlet pressure and selected an appropriate high-pressure resin pipe. A field experiment on the blockage removal of blocked CBM drainage boreholes using the proposed method was run in the Fengchun coal mine, Qijiang, Chongqing, southwest China. In this field trial, the time spent to unblock a borehole varied between 18.52 and 34.98 min, which is much shorter than using a drilling rig. After blockage removal, the average pure volume of the methane drainage of a single borehole was increased from 0.03 L/min to ~1.91–7.30 L/min, and the methane drainage concentration of a single borehole increased from 5% to ~44%–85%. The extraction effect increased significantly.

  10. Fate of sulphate removed during the treatment of circumneutral mine water and acid mine drainage with coal fly ash: Modelling and experimental approach

    Madzivire, G


    Full Text Available The treatment of acid mine drainage (AMD) and circumneutral mine water (CMW) with South African coal fly ash (FA) provides a low cost and alternative technique for treating mine wastes waters. The sulphate concentration in AMD can be reduced...

  11. CFD simulation and experimental validation of co-combustion of chicken litter and MBM with pulverized coal in a flow reactor

    Heikkinen, J.M.; Venneker, B.C.H.; di Nola, G.; de Jong, W.; Spliethoff, H. [Energy Technology section, Delft University of Technology, Leeghwaterstraat 44, NL-2628 CA Delft (Netherlands)


    The influence of co-combustion of solid biomass fuels with pulverized coal on burnout and CO emissions was studied using a flow reactor. The thermal input on a fuel feeding basis of the test rig was approximately 7 kW. Accompanied with the measurements, a reactor model using the CFD code AIOLOS was set up and first applied for two pure coal flames (with and without air staging). Reasonable agreement between measurements and simulations was found. An exception was the prediction of the CO concentration under sub-stoichiometric conditions (primary zone). As model input for the volatile matter release, the HTVM (high temperature volatile matter as defined by IFRF [IFRF, ]) was used. Furthermore, a relatively slow CO oxidation rate obtained from the literature and the ERE (Extended Resistance Equation) model for char combustion were selected. Furthermore, the model was used for simulating co-firing of coal with chicken litter (CL) and meat and bone meal (MBM). The conditions applied are relevant for future co-firing practice with high thermal shares of secondary fuels (larger than 20%). The major flue gas concentrations were quite well described, however, CO emission predictions were only qualitatively following the measured trends when O{sub 2} is available and severely under-predicted under substoichiometric conditions. However, on an engineering level of accuracy, and concerning burnout, this work shows that co-combustion of the fuels can reasonably well be described with coal combustion sub-models. (author)

  12. Experimental study on the mechanical behavior of lightweight concrete filled steel tubular short columns after fire%轻骨料钢管混凝土短柱受火后力学性能的试验研究

    王新堂; 周明; 王万祯; 仇心金


    Ceramsite concrete filled steel tube (CCFST) has not only the advantage of lightweight, but also good ductility that the ordinary concrete-filled steel tube structure has. However, study on the performance of CCFST structure after fire is still on the exploration stage. The mechanical behavior of twelve unprotected short columns of CCFST after fire was experimentally investigated. Effects of the parameters, such as the maximum value of fire temperature, fire duration, and slenderness ratio of the specimen and steel proportion on the strength and ductility of CCFST were discussed. The test results show that the CCFST short columns after fire had higher bearing capacity and better ductility, there was no descent segment in the load-displacement curves for most of the specimens after fire, and the bearing load increased again after the descent segment. It was concluded that effect of the maximum value of fire temperature and fire duration on the behavior of CCFST short columns after fire is related to geometrical parameters, and the degree of variation of the maximum value of fire temperature on the bearing capacity of the CCFST short columns increase with the slenderness ratio of the specimen.%钢管陶粒混凝土不仅具有陶粒混凝土轻质的特点,也拥有一般钢管混凝土结构的良好延性,但日的对火灾后钢管陶粒混凝土结构的性能还缺乏研究。通过对3组12根钢管陶粒混凝土短柱受火后力学性能的对比试验研究,讨论小同参数的钢管陶粒混凝土短柱受火后的剩余承载力和破坏形态的变化,重点讨论火灾最高保持温度、最高炉温持续时问、试件长细比、含钢率等参数对钢管陶粒混凝土短柱承载力和延性的影响。试验结果表明,钢管陶卡证混凝土短柱受火后仍然具有较高的承载力和良好的延性,火灾后多数试件的荷载一位移曲线并没有出现下降段,甚至出现承载力部分下降后又重新上升

  13. Oxy-coal Combustion Studies

    Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)


    The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

  14. Experimental Research on Coal Gangue Argillization of Different Minaral Composition%不同矿物组成煤的矸石泥化试验研究

    卢军; 夏云腾; 赵林盛; 沙杰


    通过对枣庄、榆林、淮北3个不同地区的煤矸石进行泥化试验,结果表明,枣庄矸石泥化现象最为严重,榆林矸石泥化次之,淮北矸石泥化较轻。经XRD分析发现,枣庄煤矸石含有大量高岭土,榆林煤矸石含有高岭土、方解石、石英等矿物,而淮北煤矸石主要矿物为石英,得出含有大量高岭石和蒙脱石是枣庄矸石泥化程度高的重要原因。经过 XRF 分析发现,煤矸石中的硅铝比分别为1.49、1.77、1.96,依次增加,并从烧失量的变化进一步验证了3种煤矸石中石英或类石英矿物的含量依次增加,从而推断出矿物组成的差异是造成矸石泥化程度不同的主要原因。在选煤厂实际生产过程中,可以预先对煤矸石的矿物组成进行测定,得出矸石泥化程度,通过采用各种手段,降低其对煤泥水的影响,保证选煤厂正常生产。%The coal gangue argillization tests are conducted from ZaoZhuang,YuLin and HuaiBei coal mine are-as,and the results show that the argillization degree of coal samples from the three places is list in a decreasing order:ZaoZhuang,YuLin and HuaiBei.According to the XRD results,there is a large content of kaolin mineral in the sam-ple from ZaoZhuang,and kaolin,calcite and quartz mineral in that from YuLin,and the primary mineral of coal gangue from Huaibei is quartz.It concludes that the important reason of high degree argillization for Zaozhuang coal gangue is contains a lot of kaolin and montmorillonite,The silica-alumina ratio obtained by XRF test is 1.49,1.77, 1 .96 for the three samples,which is an increasing order.It is also confirmed by the Ignition loss test which indicates an increasing order of quartz or similar minerals.From the above tests,it deduces that the difference in mineral com-position is the primary cause for the difference in argillization degree.In actual production process of coal preparation plant,the mineral

  15. Improved Supercritical-Solvent Extraction of Coal

    Compton, L.


    Raw coal upgraded by supercritical-solvent extraction system that uses two materials instead of one. System achieved extraction yields of 20 to 49 weight percent. Single-solvent yields are about 25 weight percent. Experimental results show extraction yields may be timedependent. Observed decreases in weight of coal agreed well with increases in ash content of residue.

  16. Water Column Methylation in Estuaries

    Schartup, A. T.; Calder, R.; Soerensen, A. L.; Mason, R. P.; Balcom, P. H.; Sunderland, E. M.


    Methylmercury (MeHg) is a neurotoxin that bioaccumulates in aquatic food webs and affects humans and wildlife through fish consumption. Many studies have measured active methylation/demethylation in ocean margin sediments but few have reported similar rates for the marine water column. This presentation will review available evidence for water column methylation in estuaries, including new experimental measurements of methylation/demethylation rates from a deep subarctic fjord in Labrador Canada collected in Spring and Fall of 2012-2013. We used these and other data to construct a mass budget for MeHg in the estuary and show that water column methylation (with rates ranging from 1.5 to 2.8 % day-1), is the largest contributor, followed by inputs from rivers (4.9 mol year-1), to the in situ pool of MeHg available for uptake by biota. By contrast, the sediment in this system is a net sink for MeHg (-1.5 mol year-1). We discuss the relationship between observed MeHg and other ancillary environmental factors (organic carbon, sulfur and nutrients) as well as implications for the response time of fish to future changes in mercury inputs.


    Herring, James R.; Rich, Fredrick J.


    Spontaneous ignition and combustion of coal is a major problem to the coal mining, shipping, and use industries; unintentional combustion causes loss of the resource as well as jeopardy to life and property. The hazard to life is especially acute in the case of underground coal mine fires that start by spontaneous ignition. It is the intention of this research to examine previously suggested causes of spontaneous ignition, to consider new evidence, and to suggest an experimental approach to determine which of these suggested causes is relevant to western U. S. coal. This discussion focuses only on causes and mechanism of spontaneous ignition.

  18. Model of coupled gas flow and deformation process in heterogeneous coal seams and its application

    ZHANG Chun-hui; ZHAO Quan-sheng; YU Yong-jiang


    The heterogeneity of coal was studied by mechanical tests. Probability plots of experimental data show that the mechanical parameters of heterogeneous coal follow a Weibull distribution. Based on elasto-plastic mechanics and gas dynamics, the model of coupled gas flow and deformation process of heterogeneous coal was presented and the effects of heterogeneity of coal on gas flow and failure of coal were investigated. Major findings include: The effect of the heterogeneity of coal on gas flow and mechanical failure of coal can be considered by the model in this paper. Failure of coal has a great effect on gas flow.

  19. Experimental study on delayed coking process with coal tar pitch%煤焦油沥青延迟焦化工艺试验研究

    王洪彬; 黄新龙; 李节; 刘淑芳


    在选定的条件下,对煤焦油沥青进行了延迟焦化工艺试验,结果表明:以煤沥青直接作为焦化进料时,可以获得质量分数为10% ~ 20%的液体产品;以煤沥青混兑蒽油为延迟焦化进料时,其液体收率大幅提高,达到28.89%,同时改善了加热炉进料性质,从而可延长装置的运行周期.由于以煤沥青作为焦化的进料,其所产的焦炭符合石油焦1B的标准,可在炼铝工业中使用,从而提高了煤沥青的附加值,增加了煤焦油加工企业的经济效益.针对煤沥青焦化液体产品性质差的特点,应采用较高氢分压、较高反应温度和较低空速对其进行加氢处理.%The experiment of delayed coking of coal tar pitch has been performed at the selected conditions. The results showed that the liquid product yield of 10% to 20% could be achieved with the feed of coal tar pitch, and it could be greatly increased to 28. 89% with the coal tar pitch feed mixed with anthracene oil. The feed properties of heaters were improved and operating cycle of the unit was extended. As the coal tar pitch was used as the feed of delayed coker, the coke product met the 1B standard for petroleum coke, which could be used in aluminum industry. As the result, the added value of coal tar pitch was raised and the economic benefits of the company were improved. The liquid products from coal tar pitch coking should be hydro-treated at a higher hydrogen partial pressure, higher reactor temperature and lower space velocity because of the low quality.

  20. Coal desulfurization through reverse micelle biocatalysis process

    Lee, K.; Yen, T.F.


    A novel bioprocess using micelle biocatalysis has been attempted to minimize several disadvantages of conventional microbial coal desulfurization scale-up processes. The reverse micelle biocatalysis process consists of a water-immiscible organic medium, a surfactant, an aqueous phase and sulfur-oxidizing bacteria or enzymes. This process has been successful for removing sulfur from bituminous coal (Illinois coal 5). The preliminary results showed that coal desulfurization through the use of cell-free enzyme extracts of Thiobacillus ferrooxidans ATCC 19859 was better than that of bacteria itself. The use of enzymes has shown potential for commercial coal desulfurization process as well. This same process is being applied to the thermophillic bacteria Sulfolobus acidocaldarius ATCC 33909. The implications of these experimental results are discussed, including a hypothetical mechanism using reverse micelle biocatalytical process for coal desulfurization.

  1. Activity and Structure of Calcined Coal Gangue


    Coal gangue was activated by means of calcination in seven temperature ranges. Systematic research was made about activation mechanism and structural evolution. Glycerin-ethanol method, SEM, MIP and XRD were used to determine the variation of structure and activation of coal gangue during the calcination.The experimental results show that because of heat treatment in the range of calcination temperature, mineral composition and microstructure of coal gangue are changed. In addition, its activity is improved evidently. The amount of lime absorbed by the sample calcined at 700 C is 2-4 times that by uncalcined coal gangue in the course of hydration. When NaOH is added to coal gangue-lime system, hydration reaction of the system is sped up and the microstructure of hydrating samples of coal gangue is improved.

  2. Separation and analysis of aromatic hydrocarbons from two Chinese coals

    DING Ming-jie; LI Wen-dian; XIE Rui-lun; ZONG Ying; CAI Ke-ying; PENG Yao-li; ZONG Zhi-min; XIE Rui-lun; WEI Xian-yong


    Separation and analysis of aromatic hydrocarbons (AHs) from coals is of considerable significance for both fuel and non-fuel use of the coals. In present work two Chinese bituminous coals were selected for separation of AHs by ultrasonic extraction with CS2 followed by column chromatography using hexane as eluent. A series of AHs were separated from the two coals and analyzed by GC/MS. FTIR was employed to characterize the raw coals and the extracted residues. The results of GC/MS analysis show that the separated AHs are mono- to tetracyclic arenes, among which the principle AHs are alkyl naphthalenes and phenanthrenes. Obvious differences in the composition and the structure of AHs exist between the two coals, i.e., the AHs from Tongting coal tend to be higher rings compared to those from Pingshuo coal both from the variety and from the abundance of the AHs. FFIR analysis shows that the raw and extracted coals are similar in terms of functional groups, suggesting that the composition and structure of CS extract, especially the AHs, from coals can be used to interpret the coal structure to some extent.

  3. Coal industry annual 1997



    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs.

  4. Coal Industry Annual 1995



    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 21 million short tons for 1995.

  5. Coal industry annual 1996



    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States.This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 24 million short tons for 1996. 14 figs., 145 tabs.

  6. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    Shields, G.L.; Smit, F.J.; Jha, M.C.


    The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction and operation of 2 t/hr process development unit (PDU). This report represents the findings of the PDU Advanced Column Flotation Testing and Evaluation phase of the program and includes a discussion of the design and construction of the PDU. Three compliance steam coals, Taggart, Indiana VII and Hiawatha, were processed in the PDU to determine performance and design parameters for commercial production of premium fuel by advanced flotation. Consistent, reliable performance of the PDU was demonstrated by 72-hr production runs on each of the test coals. Its capacity generally was limited by the dewatering capacity of the clean coal filters during the production runs rather than by the flotation capacity of the Microcel column. The residual concentrations of As, Pb, and Cl were reduced by at least 25% on a heating value basis from their concentrations in the test coals. The reduction in the concentrations of Be, Cd, Cr, Co, Mn, Hg, Ni and Se varied from coal to coal but the concentrations of most were greatly reduced from the concentrations in the ROM parent coals. The ash fusion temperatures of the Taggart and Indiana VII coals, and to a much lesser extent the Hiawatha coal, were decreased by the cleaning.

  7. 充碳塑料管壳式增湿-去湿淡化装置及过程:模拟和实验研究%Modelling and Experimental Investigation of Humidification Dehumidification Desalination Using a Carbon-Filled-Plastic Shell-Tube Column

    成怀刚; 王世昌


    The modelling and experimental investigation of a thermally coupled humidification-dehumidification desalination process using a carbon-filled-polypropylene shell-tube column are presented. A heat/mass transfer model is established to study the correlation among productivity, thermal efficiency, physicochemical parameters (gas/liquid phase temperature, heat/mass transfer coefficient, Reynolds number etc.), and operating conditions (the temperature of feed water, the flow rates of external steam, feed water, and carrier air); at the same time, the effects of operating conditions on the productivity and thermal eficiency of the column are investigated both theoretically and experimentally, which indicate that the optimum flow rates of external steam, feed water, and carrier gas are 0.18, 60, and 10kg·h-1, respectively, and the higher the feed water temperature (≤95℃) is, the greater the productivity and the thermal efficiency will be. Furthermore, performance comparison with the previous study shows that the condensate productivity of this carbon-filled-plastic column is not lower than that of the copper column, which demonstrates the practicability and feasibility of applying such a plastic column to the humidification-dehumidification desalination process.

  8. The experimental modeling of gas percolation mechanisms in a coal-measure tight sandstone reservoir: A case study on the coal-measure tight sandstone gas in the Upper Triassic Xujiahe Formation, Sichuan Basin, China

    Shizhen Tao


    Full Text Available Tight sandstone gas from coal-measure source rock is widespread in China, and it is represented by the Xujiahe Formation of the Sichuan Basin and the Upper Paleozoic of the Ordos Basin. It is affected by planar evaporative hydrocarbon expulsion of coal-measure source rock and the gentle structural background; hydrodynamics and buoyancy play a limited role in the gas migration-accumulation in tight sandstone. Under the conditions of low permeability and speed, non-Darcy flow is quite apparent, it gives rise to gas-water mixed gas zone. In the gas displacing water experiment, the shape of percolation flow curve is mainly influenced by core permeability. The lower the permeability, the higher the starting pressure gradient as well as the more evident the non-Darcy phenomenon will be. In the gas displacing water experiment of tight sandstone, the maximum gas saturation of the core is generally less than 50% (ranging from 30% to 40% and averaging at 38%; it is similar to the actual gas saturation of the gas zone in the subsurface core. The gas saturation and permeability of the core have a logarithm correlation with a correlation coefficient of 0.8915. In the single-phase flow of tight sandstone gas, low-velocity non-Darcy percolation is apparent; the initial flow velocity (Vd exists due to the slippage effect of gas flow. The shape of percolation flow curve of a single-phase gas is primarily controlled by core permeability and confining pressure; the lower the permeability or the higher the confining pressure, the higher the starting pressure (0.02–0.08 MPa/cm, whereas, the higher the quasi-initial flow speed, the longer the nonlinear section and the more obvious the non-Darcy flow will be. The tight sandstone gas seepage mechanism study shows that the lower the reservoir permeability, the higher the starting pressure and the slower the flow velocity will be, this results in the low efficiency of natural gas migration and accumulation as well as

  9. Fire response of composite columns subject to sway

    Virdi, Kuldeep

    conditions is adequately covered in the relevant standard, Eurocode 4, simplified design of unbraced composite columns for the fire limit state has not been included. Recognising this, a collaborative research project was undertaken with funding from the Research Fund for Coal and Steel. The paper describes......Composite columns, using profiled steel sections encased in concrete or steel tubes filled with concrete, are increasingly used in practice taking advantage of speed of erection as well as offering cost-effective solutions. While the design of braced and unbraced composite columns under ambient...... the scope of the project which covered control tests under ambient conditions, carried out by the author while at City University London. Other aspects covered in the project included fire tests carried out by CTICM in France, on isolated columns and on two frames designed by Leibniz Universität Hannover...

  10. Influence of Coal Particle Size on Coal Adsorption and Desorption Characteristics

    Zhang, Lei; Aziz, Naj; Ren, Ting; Nemcik, Jan; Tu, Shihao


    Accurate testing coal isotherm can play a significant role in the areas of coal seam gas drainage, outburst control, CO2 geo-sequestration, coalbed methane (CBM) and enhanced coalbed methane recovery (ECBM) etc. The effect of particle size on the CO2 and CH4 sorption capacity of bituminous coal from Illawarra, Australia was investigated at 35°C and at pressure up to 4 MPa. A unique indirect gravimetric apparatus was used to measure the gas adsorption and desorption isotherms of coal of different particle sizes ranging from around 150 urn to 16 mm. Langmuir model was used to analysis the experimental results of all gases. Coal particle size was found to have an apparent effect on the coal ash content and helium density results. Coal with larger particle size had higher ash content and higher helium density. The sorption isotherm was found to be highly sensitive with helium density of coal which was determined in the procedure of testing the void volume of sample cell. Hence, coal particle size had a significant influence on the coal sorption characteristics including sorption capacity and desorption hysteresis for CO2 and CH4, especially calculated with dry basis of coal. In this study, the 150-212 um (150 um) coal samples achieved higher sorption capacity and followed by 2.36-3.35 mm (2.4 mm), 8-9.5 mm (8 mm) and 16-19 mm (16 mm) particle size samples. However, the differences between different coal particles were getting smaller when the sorption isotherms are calculated with dry ash free basis. Test with 150 um coal samples were also found to have relatively smaller desorption hysteresis compared with the other larger particle size samples. The different results including adsorption/desorption isotherm, Langmuir parameters and coal hysteresis were all analysed with the CO2 and CH4 gases.

  11. Vitrinite-rich coal concentrate intrinsic reactivity index

    Andrés Felipe Rojas González


    Full Text Available This work defines a new reactivity coal combustion parameter called intrinsic reactivity index (IRI, combining reactive maceral fraction (vitrinite/liptinite, non-reactive maceral fraction (inertinite/intrinsic mineral matter and vitirinite reflectance averages. Coal samples from La Yolanda and Guachinte (Valle del Cauca collieries were used to evaluate the IRI; samples consisted of original and vitrinite concentrated fractions obtained from froth flotation column. This new parameter was compared to three conventional parameters: weighted mean activation energy (WMAE, peak temperature (PT and final temperature (FT. Results revealed that vitrinite concentrated fractions had higher IRI figures than original coal. This meant that vitrinite concentrated fractions presented higher reactivity to combustion than original coal. Results also showed that EAMP, TP and TF decreased with an increase in IRI, suggesting that coal combustion reactivity becomes improved when vitirinite concentration in coal is increased.

  12. Production of premium fuels from coal refuse pond material

    Honaker, R.Q.; Patil, D.P.; Sirkeci, A.; Patwardhan, A. [University of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering


    Because of increasing production of fine coal during mining over the past century and because of inefficient fine-coal recovery technologies, a vast reserve of high-quality coal now exists in refuse ponds. A novel fine-coal circuit, consisting of a hindered-bed classifier, an enhanced gravity concentrator and a flotation column, was evaluated for the recovery of fine coal from refuse ponds. The treatment of a pond derived from Pittsburgh No. 8 seam coal resulted in the production of a premium fuel containing less than 5 % ash and a calorific value of about 30,170 kJ/kg with 60% mass yield. Results from the treatment of two refuse pond materials are presented.

  13. Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

    Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.


    By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

  14. Dehalogenation of chlorinated ethenes and immobilization of nickel in anaerobic sediment columns under sulfidogenic conditions

    Drzyzga, O; EL Mamouni, R; Agathos, SN; Gottschal, JC


    A sediment column study was carried out to demonstrate the bioremediation of chloroethene- and nickel-contaminated sediment in a single anaerobic step under sulfate-reducing conditions. Four columns (one untreated control column and three experimental columns) with sediment from a chloroethene- and

  15. 煤储层水力压裂支撑剂的优选实验研究%Experimental optimization of proppant for hydraulic fracturing in coal reservoir

    张双斌; 苏现波; 郭红玉


    Aiming at the present situation that it is hard to have a yield of coalbed methane (CBM) with commercial values in more than 600 meters deep CBM wells by adopting quartz sand as proppant and active water as fracturing liquid, by means of FCES-100 fracture flow conductometer, this paper respectively tested the conductivities of quartz sand, ceramic and coated spina date seed under various closure pressures, meanwhile counted the crushed rates and observed the roundness and sphericity of proppants by using SEM. The experimental results show that all the conductivities of the three proppants are fairly good when the closure pressure is less than 15MPa. When the closure pressure is between 15 and 25 MPa, the conductivities of ceramic and coated spina date seed are relatively superior. When the closure pressure is higher than 25 MPa, only ceramic remains a relatively good conductivity. The optimization principle of the usage of proppants and fracturing liquid can be made according to the depths of coal seams for the fracturing design of CBM wells. Quartz sand should be considered when the depth is less than 600 meters. When the depth is between 600 and 1000 meters, either coated spina date seed or ceramic is usable. When the depth is more than 1000 meters, ceramic is mainly recommended.%针对我国600 m以深煤层气井采用石英砂支撑剂和活性水压裂液,难以取得商业化开发价值产气量的现状,运用FCES-100裂缝导流能力评价仪,分别测试了石英砂、陶粒和覆膜酸枣仁在不同闭合压力下的导流能力,统计了支撑剂的破碎率,并通过扫描电镜观测支撑剂的圆度和球度。实验结果表明:闭合压力小于15 MPa时,陶粒、石英砂和覆膜酸枣仁均有良好的导流能力;当闭合压力为15~25 MPa时,陶粒和覆膜酸枣仁的导流能力相对较高;当闭合压力大于25 MPa时,只有陶粒保持相对较高的导流能力。在煤层气井水力压裂设计时,可根

  16. Experimental study on seismic behavior of recycled aggregate concrete filled square steel tube columns%方钢管再生混凝土柱抗震性能试验研究

    张继承; 吕行; 范启峰; 吴胜; 王静峰


    为研究方钢管再生混凝土柱的抗震性能,采用正交设计方法设计并制作了9个试件,并对其进行拟静力试验。考虑钢管壁厚、再生骨料取代率和轴压比3个变化参数,观察试件加载全过程和破坏形态,分析试件的滞回曲线、骨架曲线、延性、耗能性能和刚度退化。结果表明:方钢管再生混凝土柱试件破坏过程及破坏形态与普通钢管混凝土柱类似,主要表现为柱底钢管的鼓曲破坏;试件的滞回曲线均比较饱满,没有明显的捏缩现象,试件的变形性能良好;再生骨料取代率对钢管再生混凝土柱的位移延性系数影响较小,主要受钢管壁厚及轴压比的影响;加载完成后,各试件的等效黏滞阻尼系数达到0.2以上,表现出良好的耗能能力;试件刚度主要受钢管壁厚和轴压比的影响,再生骨料置换率对试件刚度的影响不大;三线型的P-Δ骨架曲线模型无量纲化后,试验数据有较好的规律。%To study the seismic behavior of recycled aggregate concrete filled steel tubular(RACFST)columns,nine specimens with different thickness of steel pipe,replacement rates of recycled coarse aggregate and axial compression ratios were tested under the cyclic reversed loading.The entire loading process and failure mode were observed,the hysteretic curve,skeleton curve,ductility,dissipation ca-pacity and stiffness degradation were analyzed.It is shown that the failure process and failure mode of RACFST columns are similar to those of concrete filled steel tubular columns,in which the circular steel tube at the bottom is buckled.All the hysteretic curves which have no obvious pinching phenomenon are plump,the stability and the deformation properties of the specimens is good.The influence of re-placement rate on displacement ductility coefficient is little,while thickness of steel pipe and axial compression ratios are mainly.The e-quivalent viscous damping

  17. Research of Heating Rates Influence on Layer Coal Gasification of Krasnogorsky And Borodinsky Coal Deposit

    Jankovskiy Stanislav


    Full Text Available Experimental research of heating rate influence on coal samples gasification process of Krasnogorsky and Borodinsky coal deposit ranks A and 2B was done to define optimal heating mode in high intensification of dispersal of inflammable gases conditions. Abundance ratio of carbon monoxide and nitrogen monoxide, water vapor, carbon dioxide at four values of heating rate within the range of 5 to 30 K/min. with further definition of optimal heating rate of coals was stated.

  18. Experimental Study on Blasting Crack Propogation Velocity in Coal%煤体爆破裂纹扩展速度试验研究

    杨小林; 孙博; 褚怀保


    In order to further study the blasting crack propogation law in coal,this paper studied on its propaga tion velocity. The paint package copper wire of 0.14 mm in diameter and pencil core of 0.7 mm in diameter as the probe sensor material were selected, the blasting crack propagation velocity in internal and surface of coal was meas ured using the crack propagation test system with the detonation velocity meter. The test results show that the blasting crack propagation velocity law in coal is related to the mechanical properties of coal,wave impedance,the number of initial crack and so on. Under the guiding effect of initial crack,the blasting crack propagation velocity in coal experi ences three stages:the first rapid attenuate,approximately uniform speed stage and the final slow attenuate.%为了进一步研究煤体爆破裂纹扩展规律,以煤体爆破裂纹扩展速度为研究内容,选取φ0.14 mm漆包铜线和0.7mm铅笔芯作为探针传感器材料,利用爆速仪改进的裂纹扩展测试系统对煤体内部和表面裂纹扩展速度进行测试.试验结果表明:煤体爆破裂纹扩展速度变化规律与煤体的力学性质、波阻抗及初始裂纹数量等因素有关.在初始裂纹的导向作用下,煤体中的爆破裂纹扩展速度大致经历先迅速衰减、然后近似匀速、最后缓慢衰减3个阶段.

  19. Coal industry annual 1993


    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993.

  20. Coal - proximate analysis



    This Standard establishes a practice for the proximate analysis of coal, that is, the coal is analysed for the content of moisture, ash and volatile matter; fixed carbon is calculated. The standard provides a basis for the comparison of coals.

  1. Seepage characteristics of collapse column fillings

    Zhang Boyang; Bai Haibo; Zhang Kai


    With concealment and hysteresis, water-inrush from Karst collapse column has become an important security hazard of lower group coal mining in North China. Based on the MTS815.02 seepage test system, we analyzed the impact of consolidation pressure, initial moisture content and confining pressure on the permeability of fillings in order to study the seepage characteristics of collapse column fillings. The results show that:(1) The permeability of collapse column fillings is of the order of 10?16–10?15 magni-tude and decreases with an increase in consolidation pressure and decrease in initial moisture content. (2) The essence of filling seepage law change is the change in porosity, and a power function relationship exists between the permeability ratio and porosity ratio. (3) With increasing confining pressure, the per-meability of fillings decreases. However, under low confining pressure (1.2–4 MPa), the change of confin-ing pressure has no obvious influence on the permeability.

  2. Effect of axial mixing on RDC and PSE columns performance

    Bastani, D


    Using the experimental data obtained from two RDC columns at two different sizes (7.62 and 21.9 cm) and one PSE column with 21.5 cm size, the effect of axial mixing on the performance of these columns was studied. Comparison between the experimental and theoretical (neglecting the axial mixing) number of transfer units indicates that, this effect in PSE columns is more than RDC columns (400% and 200% respectively). These results show that this effect can increase the height of the PSE column up to 4 times for a specific efficiency. Also the results show that this effect is more in law interfacial tension systems, which shows no need of application of agitation facilities when these systems are used.

  3. Parametric study and simulation of microbubble column flotation


    A study based on a statistically designed set of experiments (Box-Behnken design) has been conducted to determine the optimum conditions for advanced physical fine coal cleaning using microbubble column flotation. The dependent variables in these experiments were mass yield and product quality (ash, sulfur and btu), while the independent variables were feed solids content, collector dosage, frother dosage, feed rate, aeration rate, and wash water rate. The most important operating parameters ...

  4. CFRP布修复震损高强混凝土柱抗震性能试验研究%Experimental investigation on seismic behavior of damaged high strength concrete columns repaired with CFRP sheets

    王苏岩; 曹怀超; 刘毅


    In order to investigate the seismic behavior of high strength concrete square columns repaired with CFRP sheets, four high strength concrete square columns were tested under low reversed cyclic loading. The test included one reference column, one undamaged column strengthened with wrapped jacketing, two damaged columns repaired with wrapped jacketing and L - shaped jacketing combined with wrapped jacketing separately. Based on the test data, the ductility, bearing capacity, energy dissipation, stiffness degradation, and CFRP sheets strain for different columns were compared systematically. The results show that the seismic behavior of two repaired columns are significantly improved. The ductility of these two columns become much better than that of reference column, but are slightly worse than the undamaged column strengthened with wrapped jacketing. Compared with the wrapped jacketing method, the method of L - shaped jacketing combined with wrapped jacketing is more effective in repairing the damaged column.%为了研究CFRP(碳纤维)布修复震损高强混凝土方柱的抗震性能,共进行了4个高强混凝土方柱试件模型的低周反复荷载试验,分别研究横向CFRP布方式加固试件和修复震损试件、横向结合L型CFRP布方式修复震损试件的抗震性能.在试验数据的基础上分析对比了试件的延性性能、承载力、能量耗散、刚度退化以及CFRP应变.研究结果表明:经过2种不同方式修复的震损破坏试件的抗震性能得到了明显改善,廷性性能远远比对比试件的好,但是仍然比未经震损直接加固的试件的延性略低,其中采用横向结合L型CFRP布方式修复的试件所表现的抗震性能较好.

  5. Columns in Clay

    Leenhouts, Robin


    This article describes a clay project for students studying Greece and Rome. It provides a wonderful way to learn slab construction techniques by making small clay column capitols. With this lesson, students learn architectural vocabulary and history, understand the importance of classical architectural forms and their influence on today's…

  6. Slender CRC Columns

    Aarup, Bendt; Jensen, Lars Rom; Ellegaard, Peter


    CRC is a high-performance steel fibre reinforced concrete with a typical compressive strength of 150 MPa. Design methods for a number of structural elements have been developed since CRC was invented in 1986, but the current project set out to further investigate the range of columns for which...

  7. Micro-CT experimental of the thermal cracking of brown coal%褐煤热破裂的显微CT实验

    孟巧荣; 赵阳升; 胡耀青; 冯增朝; 徐素国


    Using μCT225kVFCB high precision micro-CT system and a small moveable argon furnace, thermal cracking of brown coal from Pingzhuang mining in Inner Mongolia municipality was studied under different temperature.The results show that for brown coal,the big cracks( >800 μm) occupy leading position at about 100 ℃ ,the medium cracks ( 100 ~ 400 μm) are more important than others at about 200 ℃, the micro-cracks ( < 100 μm)become dominant above 300 ℃ ;threshold temperature of thermal cracking is 300 ℃, more or less;when temperature is lower than 300 ℃, the formation and evolution of crack and pore result mostly from thermal cracking, above 300 ℃, micro-cracks and pores produce mainly because coal pyrolysis produce and release oil gas, and turn coal skeleton into char gradually with temperature.%采用μCT25kVFCB型高精度显微CT试验系统并配以微型气氛炉,研究了内蒙古平庄褐煤热破裂随温度的变化关系.研究结果表明,褐煤在l00℃左右时,大裂隙(>800μm)占主导地位;200℃左右时,中等裂隙(100~400μm)占主导地位;300℃之后微裂隙(<100μm)占主导地位;热破裂的阈值为300℃左右;在300℃之前孔隙裂隙的产生发展主要是因为热破裂,300℃之后,微裂隙和孔隙的产生主要是因为煤体发生热解化学反应,油气逸出,固体骨架逐渐转变为半焦体.

  8. Research of Mechanical Treatment Influence on Rheological Properties of Coal-Water Fuel Based on Low-Grade 3B Coal

    Tolokolnikov A. A.


    Full Text Available Experimental study of mechanical treatment effect of rotary flow modulation device on coal-water fuel rheological properties were conducted. The slurry was prepared on the basis of low-grade 3B coal from Balakhtinskoe deposit.

  9. Queensland coal inventory



    Australia's black coal resources rank in the top five globally, around 50% of which are located in the sedimentary basins of Queensland. The Bowen Basin is the most prolific coal repository, hosting over 60% of the currently established resource inventory. Large volumes of thermal coal are present in the Surat and Galilee basins as well as small extensional and pull apart basins such as Blair Athol and Tarong. The article examines Queensland's coal industry from a government perspective. It first discusses the current coal market, then introduces the concept of inventory coal and explains the Australia Joint Ore Reserves Committee (JORC) code - a resource evaluation system. The stratigraphy of each of Queensland's coal basins is then discussed in sections headed Permian coals, Triassic coals, Jurassic and Cretaceous coals, and Tertiary coals. 3 figs.

  10. Coal liquefaction technology: studies of coal liquefaction, and of product upgrading and utilization


    Experimental liquefaction is reported of subbituminous Taiheiyo coal with tetralin solvent and a red mud-sulfur catalyst, at 440 C and 85 kg/cm/sup 2/ initial hydrogen pressure. A study was made of the dependence of production composition and liquids yield on residence time. The results obtained were compared with corresponding results for Miike coal and Yallourn brown coal. Studies were also made of the influence of hydrotreating conditions on the properties of the hydrotreated oil, and of the hydrotreating of Taiheiyo coal SRC liquids. Possible uses for the hydrotreated product are diesel fuel, gas oil, hydrotreated oil with cetane number 45-60, and kerosene. 22 figs., 2 tabs.

  11. Strengthening of Steel Columns under Load: Torsional-Flexural Buckling

    Martin Vild


    Full Text Available The paper presents experimental and numerical research into the strengthening of steel columns under load using welded plates. So far, the experimental research in this field has been limited mostly to flexural buckling of columns and the preload had low effect on the column load resistance. This paper focuses on the local buckling and torsional-flexural buckling of columns. Three sets of three columns each were tested. Two sets corresponding to the base section (D and strengthened section (E were tested without preloading and were used for comparison. Columns from set (F were first preloaded to the load corresponding to the half of the load resistance of the base section (D. Then the columns were strengthened and after they cooled, they were loaded to failure. The columns strengthened under load (F had similar average resistance as the columns welded without preloading (E, meaning the preload affects even members susceptible to local buckling and torsional-flexural buckling only slightly. This is the same behaviour as of the tested columns from previous research into flexural buckling. The study includes results gained from finite element models of the problem created in ANSYS software. The results obtained from the experiments and numerical simulations were compared.

  12. 煤岩蠕变-渗流耦合规律实验研究%Experimental study on creep-seepage coupling law of coal (rock)

    何峰; 王来贵; 王振伟; 姚再兴


    Based on the coal (rock) method of transient penetration, triaxial creep-seepage coupling experiment were carried out in different confining and pore pressure condition. By the creep rupture process of permeability experience, the curve of creep-permeability was fitted out, which revealed consistency between the sample of coal ( rock) permea-bility changes and creep damage. According to Issac Newton' s all differential method, a certain number of points was given on sites of creep-permeability coupled curve and interpolating, the permeability-creep equation was got.%基于煤岩瞬态渗透法,对煤岩试件进行蠕变-渗流耦合试验;对于不同的围压、孔压条件下,通过蠕变破裂过程中的渗透性试验,拟合出相应蠕变-渗透率曲线,揭示渗透率的变化和煤岩试样的蠕变损伤的一致性;据Issac Newton提出的均差法,在蠕变-渗透率耦合曲线上给出一定数量的关键点和试验点上进行插值,获得渗透率-蠕变拟合方程.

  13. Enhanced coal and mineral flotation by selective clay agglomeration

    Tao, D.; Chen, G.L.; Fan, M.M.; Zhou, X.H.; Zhao, C.; Aron, M.; Wright, J. [University of Kentucky, Lexington, KY (United States)


    The purpose is to evaluate the performance of clay binding agents for enhancing coal and mineral flotation. Mechanical and column flotation tests were conducted on coal and potash samples. Several process parameters were examined, e.g. impeller rotation speed, binder dosage, slurry solids content, and collector dosage. The results show that the Georgia-Pacific reagents improved flotation efficiency under some process conditions, especially at higher solids percentage and higher impeller rotation speed. 26 refs., 9 figs., 3 tabs.

  14. Experiment study on the propagation laws of gas and coal dust explosion in coal mine

    Rong-jun Si; Run-zhi Li; Lei Wang; Zi-ke Wu [China Coal Research Institute, Chongqing (China). Chongqing Research Institute


    An experiment of gas and coal dust explosion propagation in a single laneway was carried out in a large experimental roadway that is nearly the same with actual environment and geometry conditions. In the experiment, the time when the gas and coal dust explosion flame reaches test points has a logarithmic function relation with the test point distances. The explosion flame propagation velocity rises rapidly in the foreside of the coal dust segment and then decreases. The length of the flame area is about 2 times that of the original coal dust accumulation area. Shock wave pressure comes down to the rock bottom in the coal dust segment, then reaches a maximum peak rapidly and decreases. The theoretical basis of the research and assemble of across or explosion is supplied by the experiment conclusion. Compared with gas explosion, the force and destruction degree of a gas and coal dust explosion is much larger. 3 refs., 6 figs., 3 tabs.

  15. Experiment study on the propagation laws of gas and coal dust explosion in coal mine

    SI Rong-jun; LI Run-zhi; WANG Lei; WU Zi-ke


    The experiment of gas and coal dust explosion propagation in a single laneway was carried out in a large experimental roadway that is nearly the same with actual envi-ronment and geometry conditions. In the experiment, the time when the gas and coal dust explosion flame reaches test points has a logarithmic function relation with the test point distances. The explosion flame propagation velocity rises rapidly in the foreside of the coal dust segment and comes down after that. The length of the flame area is about 2 times that of the original coal dust accumulation area. Shock wave pressure comes down to the rock bottom in the coal dust segment, then reaches the maximum peak rapidly and comes down. The theoretical basis of the research and assemble of across or explosion is sup-plied by the experiment conclusion. Compared with gas explosion, the force and destruc-tion degree of gas and coal dust explosion is much larger.

  16. Comparison of coal separation characteristics based on different separating approaches in dry coal beneficiation flowsheet

    HE Jing-feng; ZHAO Yue-min; HE Ya-qun; LUO Zhen-fu; DUAN Chen-long


    The separation characteristic of raw coal from Luoyang mining area, China, was investigated by applying a dry coal beneficiation flowsheet with the dense medium gas-solid fluidized bed as main separating equipment. The experimental and simulation results indicate that the dense medium gas-solid fluidized bed can provide uniform distribution and stable fluctuation of bed densities at various heights. Two types of different separating approaches were compared using the dry coal beneficiation flowsheet. Compared with obtaining cleaning coal in the first stage of the flowsheet, a higher yield of the cleaning coal and better separation efficiency can be achieved when discharging gangue in the first stage. Finally, the results indicate that 64.86% pure cleaning coal with an ash content of 11.77% and 13.53% middlings were obtained, and 21.61% gangue was removed in two successive separation stages with the probable errors of 0.05 and 0.07 g/cm3, respectively.

  17. Removal of pyrite and trace elements from waste coal by dissolved-CO{sub 2} flotation and chelating agents. Final technical report, September 1, 1993--August 31, 1994

    Shiao, S.Y. [Babcock and Wilcox Co., New Orleans, LA (United States); Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)


    The overall objective of this project was to use ultrafine bubbles generated by dissolved C0{sub 2} to recover useable fuel, and reject pyrite and other minerals from a waste coal in flotation. In addition, a chelating agent was used to remove trace metals from the froth products. Illinois No. 6 waste coal obtained from a refuse thickener of a coal cleaning circuit was used as the feed in flotation. The as-received waste coal had a top size of 2400 microns. The waste coal was ground to {minus}75 microns ({minus}200 mesh) and {minus}44 microns ({minus}325 mesh). The as-received and the ground waste coal samples were subjected to flotation. Dissolved-CO{sub 2} flotation tests were performed mainly in a 3-inch diameter by 8 feet high packed column under various test conditions. Some tests were also performed in a 2-inch diameter microbubble column for comparison. The flotation performance of the waste coal in the microbubble column was higher than that for the packed column. The packing in the packed column hindered the coal flotation. The separation efficiency of the ground coal was less than that for the asreceived coal. Flotation of the waste coal was also performed in the packed column using coarser bubbles generated by dispersed C0{sub 2} and air. The separation efficiency of the ground waste coal of 44 microns top size was higher than that for dissolved-CO{sub 2} flotation. Additives were used to modify the waste coal surfaces. Triton-X 100, a nonionic surfactant and EDTA, a chelating agent, increased the separation efficiency of the waste coal.Most of the trace metals in coal were reduced in different degrees by flotation. Triton X-100 or EDTA enhanced removal of chromium, nickel, and selenium. Applying EDTA to the froth products further removed lead significantly.

  18. Fine coal circuitry using advanced physical cleaning processes

    Honaker, R.Q.; Mohanty, M.K.; Wang, D. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering; Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)


    Recent investigations have found that enhanced gravity separators (EGS) and flotation columns are highly efficient for cleaning fine coal. The test results presented in this publication show that a circuit comprised of two advanced gravity separators, i.e., a hindered-bed classifier and an EGS, and a flotation column provides an enhanced cleaning efficiency for the treatment of {minus}16 mesh coal. From in-plant experiments, the hindered-bed classifier was found to be a more efficient separation device (E{sub p} = 0.12) than coal spirals (E{sub p} = 0.18) for the treatment of a nominally 16 x 100 mesh coal. Since its efficiency declines for particle sizes less than 48 mesh, the hindered-bed classifier overflow was screened to produce a final +48 mesh concentrate and a {minus}48 mesh fraction that was subsequently treated by circuits incorporating the EGS and flotation column in combination and separately. The best overall circuits in terms of both ash and total sulfur reductions for treating the -16 mesh coal was found to be the Hindered Bed-EGS-EGS and Hindered Bed-EGS-Column circuits. Both circuits rejected over 70% of the ash and over 60% of the pyritic sulfur while recovering over 85% of the combustible material.

  19. Applied coal petrology: the role of petrology in coal utilization

    Isabel Suarez-Ruiz; John Crelling [Instituto Nacional del Carbon (INCAR-CSIC), Oviedo (Spain)


    This book is an integrated approach towards the applications of coal (organic) petrology and discusses the role of this science in the field of coal and coal-related topics. Contents are: Introduction 2. Basic factors controlling coal quality and technological behaviour of coal 3. Mining and benefication 4. Coal combustion 5. Coal gasification 6. Coal liquefaction 7. Coal carbonisation 8. Coal-derived carbons 9. Coal as a Petroleum source rock and reservoir rock 10. Environmental and health aspects 11. Other applications of coal petrology.

  20. Simulation research on the influence of eroded primary key strata on dynamic strata pressure of shallow coal seams in gully terrain

    Zhang Zhiqiang; Xu Jialin; Zhu Weibing; Shan Zhenjun


    In Huojitu Coal Mine of Shendong mining area,the dynamic strata pressure (DSP) accidents occurred when the working faces passed the gully terrain,Focusing on this problem,we used physical simulation experimental method to thoroughly study the influence of eroded overlying primary key strata (PKS) in the gully terrain on DSP of shallow coal seams in this paper.The result show that when mining activities took place in the uphill section of shallow coal seams in gully terrain and the PKS were eroded,the blocks could not form stable bond-beam structures since the horizontal force of PKS blocks in adjacent sloping surfaces were relatively small.The sliding instability of blocks caused rapid increase of the load on the sub-key strata (SKS) blocks,which resulted into coal slide and roof fall as well as sharp drop of active columns.This led to DSP phenomenon.When the PKS blocks were intact,there was no DSP phenomenon to enable blocks provide certain horizontal force to maintain stable bond-beam structure.The simulation results were verified by the mining practices of working face 21306 crossing the gully terrain in the Huojitu Coal Mine.

  1. Microwave plasma combustion of coal

    P.M. Kanilo; V.I. Kazantsev; N.I. Rasyuk; K. Schuenemann; D.M. Vavriv [Institute of Machine Building Problems of the National Academy of Sciences of Ukraine, Kharkov (Ukraine)


    Microwave plasma is studied as an alternative to oil or gas fuel for ignition and stabilisation of burning of lean coal. The study is performed on an experimental set-up, which includes a burner with a microwave plasma generator, coal and air supply systems, and measurement equipment. Power and thermochemical characteristics of the coal-plasma interaction have been measured and analysed. The obtained results indicate an essential intensification of ignition and combustion processes in the microwave burner compared to those in conventional burners. In particular, it has been demonstrated that the microwave energy consumption is only about 10% of the required expenditure of oil or gas, measured in heat equivalent. A design of an industrial microwave-plasma burner is proposed. Prospects of such burner for applications at industrial boilers of power plants are discussed. 6 refs., 4 figs., 2 tabs.

  2. Clean Coal Program Research Activities

    Larry Baxter; Eric Eddings; Thomas Fletcher; Kerry Kelly; JoAnn Lighty; Ronald Pugmire; Adel Sarofim; Geoffrey Silcox; Phillip Smith; Jeremy Thornock; Jost Wendt; Kevin Whitty


    Although remarkable progress has been made in developing technologies for the clean and efficient utilization of coal, the biggest challenge in the utilization of coal is still the protection of the environment. Specifically, electric utilities face increasingly stringent restriction on the emissions of NO{sub x} and SO{sub x}, new mercury emission standards, and mounting pressure for the mitigation of CO{sub 2} emissions, an environmental challenge that is greater than any they have previously faced. The Utah Clean Coal Program addressed issues related to innovations for existing power plants including retrofit technologies for carbon capture and sequestration (CCS) or green field plants with CCS. The Program focused on the following areas: simulation, mercury control, oxycoal combustion, gasification, sequestration, chemical looping combustion, materials investigations and student research experiences. The goal of this program was to begin to integrate the experimental and simulation activities and to partner with NETL researchers to integrate the Program's results with those at NETL, using simulation as the vehicle for integration and innovation. The investigators also committed to training students in coal utilization technology tuned to the environmental constraints that we face in the future; to this end the Program supported approximately 12 graduate students toward the completion of their graduate degree in addition to numerous undergraduate students. With the increased importance of coal for energy independence, training of graduate and undergraduate students in the development of new technologies is critical.

  3. 煤气化过程痕量元素迁移实验研究%Experimental Study of Trace Elements Release From Coal Gasification Process

    蔡铭; 许世森; 郜时旺; 吴龙; 刘练波; D.Dugwell; R.Kandiyoti


    煤气化过程痕量元素排放引起的环境问题是成为关注的热点之一.为了研究和掌握气流床气化炉中的痕量元素排放规律,利用高温高压金属丝网(wire-mesh reactor,WMR)反应器模拟气流床气化不同的气化和热解条件,对煤样及反应器产生的煤焦样中的As、Se、Pb、V、Co、Ba、Cr、Mn.痕量元素进行电感耦合等离子体-质谱(inductively coupled plasma-mass spectrometry,ICP-MS)分析.WMR实验结果与气化炉中试装置试验煤、灰、渣样品中数据及热力学模型模拟结果进行对比分析.结果表明,中试试验与热力学模拟结果比较吻合,中试试验条件下痕量元素反应达到了平衡状态;WMR试验中Pb、V、Ba、Mn及Co的排放规律与热力学模拟结果比较一致,而As和Se的试验结果与热力学模拟结果相差较大,可能是WMR试验中反应时间较短,受动力学因素影响较大的原因.%The release of toxic trace elements from coal gasification is a matter of environmental concern.A laboratory scale wire-mesh reactor (WMR) was used to simulate trace element releases from coal particles in an entrained flow gasifier.Char samples were produced from WMR under various gasification and pyrolysis conditions,within the operating window of the gasifier.The samples of char as well as raw coal were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) for the contents of an array of mostly toxic trace elements: As,Se,Pb,V,Co,Ba,Cr and Mn.Coal and slag samples from a pilot scale,entrained flow gasifier were also analyzed for comparison with the WMR data.There is good agreement between the thermodynamic predictions and the pilot scale data,showing that equilibrium with respect to trace element partitioning is reached in the pilot scale gasifier.Agreement with the WMR data is less consistent.There is agreement for the elements Pb,V,Ba,Mn and possibly Co.It is inconsistent for As and Se,which may be due to a kinetic limitation

  4. Experimental study on seismic performance of concrete columns reinforced by steel-FRP composite bars%钢-连续纤维复合筋增强混凝土柱抗震性能试验研究

    孙泽阳; 吴刚; 吴智深; 张敏


    The seismic performance of concrete columns reinforced by Steel-FRP(Fiber Reinforced Polymer) Composite Bar(SFCB) is quite different from that of ordinary RC(Reinforced Concrete) columns.Horizontal cyclic loading tests were conducted on concrete columns reinforced by SFCB and ordinary steel bars,separately,with an axial compression ratio of 0.12.Fiber types(basalt and carbon fibers) and steel/fiber ratio of SFCB were the main variable parameters.Test results showed that: ①compared with ordinary RC column,concrete columns reinforced by SFCB had stable post-yield stiffness,and the load could increase significantly after the yielding of SFCB inner steel bar;②due to the post-yield stiffness of SFCB,SFCB reinforced concrete column had less column base curvature demand than ordinary RC column at the same column cap lateral deformation level,and therefore smaller unloading residual deformation could be achieved;③the outer FRP type of SFCB significantly influenced the performance of SFCB reinforced concrete columns,and steel-BFRP(basalt FRP) composite bar reinforced concrete columns had better ductility(longer effective length of post-yield stiffness) and smaller unloading residual deformation than steel-CFRP(carbon FRP) composite bar columns under the same unloading displacement.%具有稳定二次刚度和良好震后可修复性的钢-连续纤维复合筋(SFCB)增强混凝土柱的抗震性能与普通RC柱有较大差别,本文对在水平往复荷载作用下,轴压比为0.12的4个SFCB增强混凝土柱及1个RC对比柱的抗震性能进行试验研究。SFCB增强混凝土柱主要变化参数为SFCB中的纤维种类(玄武岩纤维和碳纤维)和钢/纤维比例。研究结果表明:①SFCB增强混凝土柱相对普通RC柱具有稳定的二次刚度,在复合筋内芯钢筋屈服后,SFCB增强混凝土柱承载力仍可稳定提高;②SFCB增强混凝土柱由于复合筋的二次刚度,实现了在与普通RC柱

  5. Mini-columns for Conducting Breakthrough Experiments. Design and Construction

    Dittrich, Timothy M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ware, Stuart Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    Experiments with moderately and strongly sorbing radionuclides (i.e., U, Cs, Am) have shown that sorption between experimental solutions and traditional column materials must be accounted for to accurately determine stationary phase or porous media sorption properties (i.e., sorption site density, sorption site reaction rate coefficients, and partition coefficients or Kd values). This report details the materials and construction of mini-columns for use in breakthrough columns to allow for accurate measurement and modeling of sorption parameters. Material selection, construction techniques, wet packing of columns, tubing connections, and lessons learned are addressed.

  6. Biogenic Methane from Coal: The Oxidation Factor

    Gallagher, L. K.; Glossner, A. W.; Landkamer, L.; Figueroa, L. A.; Mandernack, K. W.; Munakata Marr, J.


    Vast reserves of coal represent an untapped resource that can be used to produce methane gas, a cleaner energy alternative compared to standard fossil fuels. Microorganisms have demonstrated the ability to utilize coal as a carbon source, producing biogenic methane. With increasing demand for cleaner energy resources, understanding and enhancing biogenic methane production has become an area of active research. The conversion of coal to methane by microorganisms has been demonstrated experimentally by a number of research groups, but the state of the coal used as a substrate has not always been reported and may impact biogenic methane production. Microcosm experiments were designed in order to assess how the oxidation state of coal might influence methane production (e.g. as in a dewatered coal-bed natural gas system). Oxidized and un-oxidized coal samples from the Powder River Basin were incubated in microcosms inoculated with an enrichment culture that was derived from coal. Microcosms were characterized by headspace gas analysis, organic acid production, functional gene abundance (qPCR), and pyrosequencing of the 16S rRNA gene. Although the microbial consortium demonstrated the ability to utilize both oxidized and un-oxidized coal as a sole carbon source to generate methane, it was produced in higher quantities from the un-oxidized coal. This microbial community was dominated by Methanobacteriaceae (45%), epsilon-Proteobacteria (32%) and delta-Proteobacteria (13%). The results of this study provide a basis to develop strategies to enhance biogenic methane production from coal, as well as demonstrate the need for careful substrate preparation for inter-study comparisons.

  7. Thiophenic Sulfur Compounds Released During Coal Pyrolysis

    Xing, Mengwen; Kong, Jiao; Dong, Jie; Jiao, Haili; Li, Fan


    Abstract Thiophenic sulfur compounds are released during coal gasification, carbonization, and combustion. Previous studies indicate that thiophenic sulfur compounds degrade very slowly in the environment, and are more carcinogenic than polycyclic aromatic hydrocarbons and nitrogenous compounds. Therefore, it is very important to study the principle of thiophenic sulfur compounds during coal conversion, in order to control their emission and promote clean coal utilization. To realize this goal and understand the formation mechanism of thiophenic sulfur compounds, this study focused on the release behavior of thiophenic sulfur compounds during coal pyrolysis, which is an important phase for all coal thermal conversion processes. The pyrolyzer (CDS-5250) and gas chromatography–mass spectrometry (Focus GC-DSQII) were used to analyze thiophenic sulfur compounds in situ. Several coals with different coal ranks and sulfur contents were chosen as experimental samples, and thiophenic sulfur compounds of the gas produced during pyrolysis under different temperatures and heating rates were investigated. Levels of benzothiophene and dibenzothiophene were obtained during pyrolysis at temperatures ranging from 200°C to 1300°C, and heating rates ranging from 6°C/ms to 14°C/ms and 6°C/s to 14°C/s. Moreover, the relationship between the total amount of benzothiophene and dibenzothiophene released during coal pyrolysis and the organic sulfur content in coal was also discussed. This study is beneficial for understanding the formation and control of thiophenic sulfur compounds, since it provides a series of significant results that show the impact that operation conditions and organic sulfur content in coal have on the amount and species of thiophenic sulfur compounds produced during coal pyrolysis. PMID:23781126

  8. Assessing coal burnout

    Lowe, A. [Pacific Power, Sydney, NSW (Australia)


    Recent research has allowed a quantitative description of the basic process of burnout for pulverized coals to be made. The Cooperative Research Centre for Black Coal Utilization has built on this work to develop a coal combustion model which will allow plant engineers and coal company representatives to assess their coals for combustion performance. The paper describes the model and its validation and outlines how it is run. 2 figs.

  9. Colombian coal focus

    Warden-Fernandez, J.; Rodriguez, L.E. [University of Dundee, Dundee (United Kingdom)


    The paper reviews the development of Colombia's coal industry over recent years. Colombia has recently modernised its mining code, Law 685 of 2001 concerning mineral rights and including the concept of sustainable development. The article discusses the legislation, analyses trends in Columbia's income from the coal and mineral industries (nickel, gold, emerald), and briefly discusses coal reserves, mining projects, coal exports and markets for Colombian coal. 7 refs., 7 figs., 4 tabs.

  10. Coal markets in transition

    Romer, R.


    Describes Colorado's coal industry, and the implementation of a nine point mining plan announced in 1988. This plan includes an environmental regulatory review, coal royalty reform, production and marketing incentives, clean coal and clean air issues, and promotion of the coal industry. Other issues to be addressed are abandoned mine reclamation, abandoned mine safety and land reclamation after surface mining. International markets for Colorado coal are also discussed.

  11. Coal combustion products

    Kalyoncu, R.S.; Olson, D.W.


    Coal-burning powerplants, which supply more than half of U.S. electricity, also generate coal combustion products, which can be both a resource and a disposal problem. The U.S. Geological Survey collaborates with the American Coal Ash Association in preparing its annual report on coal combustion products. This Fact Sheet answers questions about present and potential uses of coal combustion products.

  12. Buckling driven debonding in sandwich columns

    Østergaard, Rasmus Christian


    A compression loaded sandwich column that contains a debond is analyzed using a geometrically non-linear finite element model. The model includes a cohesive zone along one face sheet/core interface whereby the debond can extend by interface crack growth. Two geometrical imperfections are introduced......; a global imperfection of the sandwich column axis and a local imperfection of the debonded face sheet axis. The model predicts the sandwich column to be very sensitive to the initial debond length and the local face sheet imperfection. The study shows that the sensitivity to the face sheet imperfection...... results from two mechanisms: (a) interaction of local debond buckling and global buckling and (b) the development of a damaged zone at the debond crack tip. Based on the pronounced imperfection sensitivity, the author predicts that an experimental measurement of the strength of sandwich structures may...

  13. Computational analysis of ozonation in bubble columns

    Quinones-Bolanos, E. [Univ. of Guelph, School of Engineering, Guelph, Ontario (Canada)]|[Univ. de Cartagena, Facultad de Ciencias e Ingenieria, Cartagena de Indias (Colombia); Zhou, H.; Otten, L. [Univ. of Guelph, School of Engineering, Guelph, Ontario (Canada)]. E-mail:


    This paper presents a new computational ozonation model based on the principle of computational fluid dynamics along with the kinetics of ozone decay and microbial inactivation to predict the performance of ozone disinfection in fine bubble columns. The model can be represented using a mixture two-phase flow model to simulate the hydrodynamics of the water flow and using two transport equations to track the concentration profiles of ozone and microorganisms along the height of the column, respectively. The applicability of this model was then demonstrated by comparing the simulated ozone concentrations with experimental measurements obtained from a pilot scale fine bubble column. One distinct advantage of this approach is that it does not require the prerequisite assumptions such as plug flow condition, perfect mixing, tanks-in-series, uniform radial or longitudinal dispersion in predicting the performance of disinfection contactors without carrying out expensive and tedious tracer studies. (author)

  14. Behavior of Columns During Earthquakes

    National Oceanic and Atmospheric Administration, Department of Commerce — The behavior of columns during earthquakes is very important since column failures may lead to additional structural failures and result in total building collapses....

  15. Determination of Two Columns Performance


    When protein is analyzed by high performance liquid chromatography (HPLC), the selection of column is one of the most important factors. There are four quality control parameters for the column, which are theoretical plates n, capacity facto

  16. NMFS Water Column Sonar Database

    National Oceanic and Atmospheric Administration, Department of Commerce — Water column sonar data are an important component of fishery independent surveys, habitat studies and other research. NMFS water column sonar data are archived here.


    李青宁; 何迪; 王鹏; 姜维山


    A new kind of precast concrete segmental columns has been put forward in this paper .Its core concrete is constrainted by high-strength compound spiral stirrups and the exterior steel plate hoop penetrated by the bolt bar used for the connection area .It is compared the three assembled long columns under different width of the exterior steel plate hoop and axial pressure ratio to the one cast-in-place long column .It is proved that the new kind of precast concrete segmental columns is better for the anti-seismic capacity and safe in the node connection area so that the cast-in-place long column can be replaced .ANSYS FEM software is used to take contrastive analysis for the column of hysteretic behavior based on the width of the exterior steel plate hoop and axial pressure ratio , the results show that numerical simulation meets well with the experiment , the ANSYS numerical analysis model of precast concrete segmental columns is feasible and correct .The ANSYS FEM can be used for the numerical simulation and the analysis of mechanical performance study of the assembled column structures .%提出一种高强复合螺旋箍筋约束混凝土、外包钢板箍和横穿栓筋连接的新型装配整体式柱。通过对不同钢板箍厚度和轴压比下的3个装配式长柱与1个现浇长柱进行拟静力对比试验,证明这种装配整体式柱抗震性能良好,节点连接安全可靠,可以代替现浇整体柱。以钢板箍厚度与轴压比为研究变量,利用ANSYS对柱的滞回性能进行对比分析,研究结果表明:数值模拟与试验吻合较好,提出的装配整体式柱ANSYS数值分析模型合理可行,可运用ANSYS程序对装配整体式柱结构进行有限元数值模拟和受力性能研究分析。

  18. Coal data: A reference


    This report, Coal Data: A Reference, summarizes basic information on the mining and use of coal, an important source of energy in the US. This report is written for a general audience. The goal is to cover basic material and strike a reasonable compromise between overly generalized statements and detailed analyses. The section ``Supplemental Figures and Tables`` contains statistics, graphs, maps, and other illustrations that show trends, patterns, geographic locations, and similar coal-related information. The section ``Coal Terminology and Related Information`` provides additional information about terms mentioned in the text and introduces some new terms. The last edition of Coal Data: A Reference was published in 1991. The present edition contains updated data as well as expanded reviews and additional information. Added to the text are discussions of coal quality, coal prices, unions, and strikes. The appendix has been expanded to provide statistics on a variety of additional topics, such as: trends in coal production and royalties from Federal and Indian coal leases, hours worked and earnings for coal mine employment, railroad coal shipments and revenues, waterborne coal traffic, coal export loading terminals, utility coal combustion byproducts, and trace elements in coal. The information in this report has been gleaned mainly from the sources in the bibliography. The reader interested in going beyond the scope of this report should consult these sources. The statistics are largely from reports published by the Energy Information Administration.

  19. Investigation of polycyclic aromatic hydrocarbons from coal gasification.

    Zhou, Hong-cang; Jin, Bao-sheng; Zhong, Zhao-ping; Huang, Ya-ji; Xiao, Rui; Li, Da-ji


    The hazardous organic pollutants generated from coal gasification, such as polycyclic aromatic hydrocarbons(PAHs), are highly mutagenic and carcinogenic. More researchers have paid particular attention to them. Using air and steam as gasification medium, the experiments of three kinds of coals were carried out in a bench-scale atmospheric fluidized bed gasifier. The contents of the 16 PAHs specified by US EPA in raw coal, slag, bag house coke, cyclone coke and gas were measured by HPLC to study the contents of PAHs in raw coal and the effects of the inherent characters of coals on the formation and release of PAHs in coal gasification. The experimental results showed that the distributions of PAHs in the gasified products are similar to raw coals and the total-PAHs content in coal gasification is higher than in raw coal(except Coal C). The total-PAHs contents increase and then decrease with the rise of fixed carbon and sulfur of coal while there has an opposite variation when volatile matters content increase. The quantities of PAHs reduce with the increase of ash content or the drop of heating value during coal gasification.

  20. Investigation of polycyclic aromatic hydrocarbons from coal gasification

    ZHOU Hong-cang; JIN Bao-sheng; ZHONG Zhao-ping; HUANG Ya-ji; XIAO Rui; LI Da-ji


    The hazardous organic pollutants generated from coal gasification, such as polycyclic aromatic hydrocarbons(PAHs), are highly mutagenic and carcinogenic. More researchers have paid particular attention to them. Using air and steam as gasification medium, the experiments of three kinds of coals were carried out in a bench-scale atmospheric fluidized bed gasifier. The contents of the 16 PAHs specified by US EPA in raw coal, slag, bag house coke, cyclone coke and gas were measured by HPLC to study the contents of PAHs in raw coal and the effects of the inherent characters of coals on the formation and release of PAHs in coal gasification. The experimental results showed that the distributions of PAHs in the gasified products are similar to raw coals and the total-PAHs content in coal gasification is higher than in raw coal(except Coal C). The total-PAHs contents increase and then decrease with the rise of fixed carbon and sulfur of coal while there has an opposite variation when volatile matters content increase. The quantities of PAHs reduce with the increase of ash content or the drop of heating value during coal gasification.

  1. 76 FR 35968 - Maintenance of Incombustible Content of Rock Dust in Underground Coal Mines


    ... relaxation for lower volatile coal. In its experimental studies of the effect of particle size on explosion... approximately 415 active underground bituminous coal mines employing 47,119 miners. Table 1 presents the 415...

  2. 强约束轴心受压钢管柱耐火性能试验研究%Experimental study on the fire-resistance of steel tube columns with axial compression and strong constraints

    屈立军; 潘翀; 李焕群


    为正确评估强约束钢管柱的耐火性能,利用自行研制的杆系结构构件温度轴力测量装置,采用恒载升温试验方法,设5级初应力水平,6种长细比,对30根Q345钢管柱进行试验研究,揭示轴心受压钢管柱在强约束下的耐火性能。试验结果表明:强约束钢管柱在温升作用下的温度应力相当大,对钢管柱破坏有决定性作用,在耐火设计与评估中必须考虑。钢管柱在高温作用下,破坏前其弹塑性性质较为明显。相同长细比的构件,在较高的初始应力水平作用下,极限承载力大、温度应力小、临界温度低;反之相反。在相同初应力水平下,长细比对强约束钢管柱的极限承载力和温度应力的影响并不敏感,但长细比大的试件为失稳破坏,破坏后变形很大;长细比较小的试件为强度破坏,破坏后变形较小。以试验数据为基础给出两端固定Q345钢管柱的下限临界温度回归计算公式,可用于火灾中约束刚度不变的钢结构耐火设计与评估。%In order to evaluate the fire resistance of steel tube columns with strong constraints, a self-developed thermal internal force measurement device for frame structure members was employed. Test under elevated temperature and constant loading was conducted for 30 steel tube columns of Q345 with 5 grades of initial stress levels and 6 slenderness ratios, to reveal the fire resistance of such columns. The results show that under elevated temperature the thermal stress of the steel tube columns is great, and should be considered in the fire resistance design and evaluation. Under elevated temperature, the steel tube columns exhibite obvious elasto-plastic properties before failure. With identical slenderness ratio, the columns with higher initial stress level hadve larger bearing capability, lower thermal stress and critical temperature, when compared with the columns with lower initial stress levels

  3. 微分散轮盘塔萃取净化湿法磷酸的实验研究%Experimental study on purification of wet-process phosphoric acid in micro-dispersion rotating disc column

    祝杰; 叶世超; 白洁; 吴振元; 李俊宏; 曾晓娟


      采用筛网孔径为75μm 的微分散轮盘萃取塔净化湿法磷酸,在 TBP+煤油/磷酸/水为体系的实验条件下,研究了浓度为55%的湿法磷酸的萃取及反萃特性,考察了不同转速、总体积通量和相比对萃取率和反萃取率的影响。研究结果表明,萃取率随转速及相比的增大而增大,随总体积通量的增大而减小,最优萃取条件:转速为250 r/min,总体积通量为56.62 L/(m2·min),相比为4,磷酸萃取率可达55%;反萃率随转速的增大而增大,随相比及总体积通量的增大而减小,最优反萃条件:转速为300 r/min,总体积通量为56.62 L/(m2·min),相比为6,磷酸反萃率可达85%。通过量纲为1化拟合出体积传质系数经验计算式为 KXa=1.53×10−3p−0.28135Fr0.344493W/D,与实验规律吻合,可以为工业放大设计和优化提供了较好的实验依据。%  The mesh size of 75 μm of micro-dispersion rotating disc column was used to purify wet-process phosphoric acid with the system of TBP+kerosene/phosphoric acid/water. The effects of rotate speed,volume flow,phase ratio on the extraction and re-extraction of phosphoric acid with the content of 55% were studied. Results showed that the extraction rate increased with the increase of rotate speed and phase ratio,and decreased with the increase of volume flow. Under the optimum conditions of rotate speed of 250 r/min,volume flow of 56.62 L/(m2·min),phase ratio of 4,and the extraction rate can be as high as 55%. The re-extraction rate was improved with the improvement of rotate speed,fell with the raise of phase ratio and volume flow. Under the best re-extraction conditions of rotate speed of 300r/min,volumetric flow of 56.62 L/(m2·min) phase ratio of 6,the re-extraction rate could be up to 85%. Non-dimensional expression for the volumetric mass transfer coefficient can be expressed asKXa=1.53×10−3p−0.28135Fr0.344493W/D,and the simulation matched the

  4. Energy-Saving Vibration Impulse Coal Degradation at Finely Dispersed Coal-Water Slurry Preparation

    Moiseev V.A.


    Full Text Available Theoretical and experimental research results of processes of finely dispersed coal-water slurry preparation for further generation of energetic gas in direct flow and vortex gas generator plants have been presented. It has been stated that frequency parameters of parabolic vibration impulse mill influence degradation degree. Pressure influence on coal parameters in grinding cavity has been proven. Experimental researches have proven efficiency of vibration impulse mill with unbalanced mass vibrator generator development. Conditions of development on intergranular walls of coal cracks have been defined.

  5. 碳纤维布改善钢筋混凝土短柱延性的试验研究%Experimental study on the application of continuous carbon fiber sheet to improve the ductility of reinforced concrete short columns

    赵彤; 张景明; 谢剑; 刘明国


    Based on the experiments of four reinforced concrete short columns under cyclic loading, the effectiveness of the new method of using continuous carbon fiber sheet(CFS) on strengthening the reinforced concrete short columns for increasing their ductility is studied. Through the test data analysis, it is found that the ductility of the reinforced concrete short columns is significantly improved. And the reason, why the ductility of the hybrid columns is improved, is also analyzed.%通过横向包裹碳纤维布的钢筋混凝土短柱在低周反复荷载作用下受力性能的试验研究,验证了碳纤维布对钢筋混凝土短柱延性的改善作用。经碳纤维布包裹的钢筋混凝土短柱,其延性得到了显著改善,但承载能力却变化不大。试验还发现,碳纤维布在使用中存在一个作用效率的问题,碳纤维布包裹层数愈多,其作用效率愈低。

  6. Occurrence and mobility of toxic elements in coals from endemic fluorosis areas in the Three Gorges Region, SW China.

    Xiong, Yan; Xiao, Tangfu; Liu, Yizhang; Zhu, Jianming; Ning, Zengping; Xiao, Qingxiang


    Fluorine (F) is a topic of great interest in coal-combustion related endemic fluorosis areas. However, little extent research exists regarding the environmental geochemistry of toxic elements that are enriched in coals and coal wastes in traditional endemic fluorosis areas, particularly focusing on their occurrences and mobilities during the weathering-leaching processes of coals and coal wastes in the surface environment. This paper addressed the issue of toxic elements in coals and coal wastes in the Three Gorges Region, Southwest (SW) China, where endemic fluorosis has historically prevailed, and investigated the distribution, occurrence, mobility features, and associated potential health risks. For this purpose, a modified experiment combined with long-term humidity cell test and column leaching trial was applied to elucidate the mobility of toxic elements in coals and coal wastes. In addition, sequential chemical extraction (SCE) was used to ascertain the modes of occurrence of toxic elements. The results demonstrated that the contents of toxic elements in the study area followed the order: stone coals > gangues > coal balls > coals. Furthermore, modes of occurrence of toxic elements were obviously different in coals and coal wastes. For example, cadmium (Cd) was mainly associated with monosulfide fraction in coals, molybdenum (Mo) and arsenic (As) were mainly associated with carbonate and silicate in coal gangues and stone coals, chromium (Cr) mainly existed in silicate and insoluble matter in coal gangues and coal balls, thallium (Tl) mainly occurred in organic matter in stone coals and sulfide in coals, and the occurrence of antimony (Sb) varied with different kinds of samples. Moreover, a large amount of toxic elements released to the leachates during the weathering and leaching process, which might pollute the environment and threaten human health. Based on the geo-accumulation index (Igeo), single factor index (Pi) and Nemerow index (PN), soils in the

  7. 碎石桩传力特性的实验研究及其理论分析%Experimental study and theoretical analysis of the stress propagation in a stone column

    慕青松; 马崇武; 马君伟; 花拓


    应用自行设计制造的二维实验设备,通过杠杆砝码加压与测力环直接测量桩底压强相结合的方法,研究了不同长度碎石桩的传力方式和破坏模式。实验发现,直径和填料一定的碎石桩存在一个临界桩长(临界长径比),当桩长跨越临界值时,碎石桩内部以及与桩周土之间的传力方式要发生改变。桩长小于临界值时,随着桩顶荷载增加,桩底的承载贡献率增大,而桩周土的承载贡献率减小。与之相反,桩长大于临界值时,随着桩顶荷载增加,桩底的承载贡献率减小,而桩周土的承载贡献率增大。实验还发现短桩和长桩的不同传力方式决定了不同的破坏模式。随着桩顶荷载增加,短桩将发生桩底刺入破坏,而长桩将发生顶端鼓胀剪切破坏。借鉴Janssen的“粮仓效应”经典理论,建立了二维碎石桩的传力模型。该模型对长桩定性符合良好,但对短桩不适合。%An experiment apparatus designed by ourselves, which consists of a lever-weight loading part and column-bottom-pressure ergometers, was used to investigate the stress propagation characteristics and failure modes in stone columns. The experiment results show the existence of a critical value in the length of a stone column. For a longer stone column with a length over the critical value, the growth of top pressure would lead to the increase in the contributing percentage of friction force on the side soil for balancing top pressure, as well as leading to the decrease in the contributing percentage of bottom pressure for balancing top pressure. However, it was converse in a shorter stone column with a length under the critical value. Correspondingly, the failure mode of longer columns was also different from that of shorter ones. The shorter stone columns failed as they plunged into the base soil while the longer ones were damaged by the bulge-shear near the top. To interpret the above

  8. 密柱钢板深梁结构抗震性能试验研究%Experimental study on seismic behavior of structure with dense columns-deep steel plate beams

    董宏英; 张力嘉; 曹万林; 乔崎云; 刘恒超


    提出了一种内藏密柱钢板深梁混凝土组合剪力墙,密柱钢板深梁为其核心钢构.为研发高性能密柱钢板深梁结构,对4个具有不同设计参数的试件进行了低周反复荷载试验.试件的密柱分为方钢管混凝土、圆钢管混凝土、工字钢3种截面,钢板深梁分为Q235,Q345两种钢材,试件剪跨比为1.5.基于试验,分析了各试件的承载力、刚度及退化过程、延性、滞回特性、耗能、损伤与破坏过程,提出了密柱钢板深梁结构承载力计算模型,计算结果与实测结果符合较好.研究结果表明:“强密柱、弱钢板深梁”型结构可实现延性屈服机制;密柱截面用钢量相同时,采用圆钢管混凝土密柱的结构性能最好;与采用Q345钢板深梁的结构相比,采用Q235钢板深梁的结构虽承载力略小但延性更好;密柱钢板深梁结构具有良好的抗震性能和延性屈服机制.%The composite concrete shear wall embedded with dense columns-deep steel plate beams as the core structure was proposed.In order to investigate a high-performance structure with dense columns-deep steel plate beams, low cyclic loading experiments were carried out on four specimens with different design parameters.Three section styles, including concrete filled square steel tube col-umn, concrete filled circular steel tube column, and I-section steel column, were adopted for dense columns.The steel strengths of deep beams included two grades, Q235 and Q345.The shear span ratios of all the specimens were 1.5.Based on the experiments, the load-bearing capacities, stiffness and deterioration processes, ductilities, hysteretic behaviors, energy dissipations, damage and failure processes of specimens were analyzed.The load-bearing capacity calculation model was established, and the calculation results were in good agreement with the test results.The investigation results show that the structure with“strong columns

  9. A new approach to study fast pyrolysis of pulverized coal

    Wang, J.; Yao, J.; Lin, W. [Chinese Academy of Sciences, Institute of Chemical Metallurgy Fast Reactions Laboratory, Beijing, BJ (China)


    An experimental study of the effects of varying bed temperature and coal particle size on the fast pyrolysis of pulverized coal in a downer reactor is described. A Datong bituminous coal (particle size 0.5 and 0.34 mm) was studied at temperatures ranging from 592{sup o} C to 720{sup o} C. The experiments were conducted in a batch apparatus. An on-line gas analyzer was used to measure carbon dioxide release curves. The experimental data were used to develop a pyrolysis model that quantifies the fast heating of fine coal particles. 14 refs., 4 figs., 2 tabs.

  10. Column: Every Last Byte

    Simson Garfinkel


    Full Text Available Inheritance powder is the name that was given to poisons, especially arsenic, that were commonly used in the 17th and early 18th centuries to hasten the death of the elderly. For most of the 17th century, arsenic was deadly but undetectable, making it nearly impossible to prove that someone had been poisoned. The first arsenic test produced a gas—hardly something that a scientist could show to a judge. Faced with a growing epidemic of poisonings, doctors and chemists spent decades searching for something better.(see PDF for full column

  11. Removal of hydrogen sulfide gas and landfill leachate treatment using coal bottom ash.

    Lin, C Y; Hesu, P H; Yang, D H


    Coal bottom ashes produced from three thermal power plants were used in column and batch experiments to investigate the adsorption capacity of the coal ash. Hydrogen sulfide and leachates collected from three sanitary landfill sites were used as adsorbate gas and solutions, respectively. Experimental results showed that coal bottom ash could remove H2S from waste gas or reduce the concentrations of various pollutants in the leachate. Each gram of bottom ash could remove up to 10.5 mg of H2S. In treating the landfill leachate, increasing ash dosage increased the removal efficiency but decreased the adsorption amount per unit mass of ash. For these tested ashes, the removal efficiencies of chemical oxygen demand (COD), NH3-N, total Kjeldhal nitrogen (TKN), P, Fe3+, Mn2+, and Zn2+ were 36.4-50, 24.2-39.4, 27.0-31.1, 82.2-92.9, 93.8-96.5, 93.7-95.4, and 80.5-82.2%, respectively; the highest adsorption capacities for those parameters were 3.5-5.6, 0.22-0.63, 0.36-0.45, 0.027-0.034, 0.050-0.053, 0.029-0.032, and 0.006 mg/g of bottom ash, respectively. The adsorption of pollutants in the leachate conformed to Freundlich's adsorption model.

  12. Small scale experiment on the plasma assisted thermal chemical preparation and combustion of pulverized coal

    Masaya, Sugimoto; Koichi, Takeda [Akita Prefectural University (Japan); Solonenko, O.P. [Institute of Theoretical and Applied Mechanics, Novosibirsk (Russian Federation); Sakashita, M.; Nakamura, M. [Japan Technical Information Service, Tokyo (Japan)


    Ignition and stable combustion of pulverized coal with Nitrogen and Air plasmas are investigated experimentally for some different types of coal. The experimental results show that air plasma has strong effect for ignition and stabilization of coal combustion. In addition, suppression of NO{sub x} production could be possible even in air plasma. It is possible to ignite and burn stably for the inferior coal that contains volatile matter in the ratio of only 10% of dry total mass. (authors)

  13. 复合毛细芯热柱传热极限的建模方法及实验研究%Modeling Method and Experimental Study on Heat Transfer Limit of Composite Wick Heat Column

    陶素连; 周钦河; 林庆文


    Aiming at existing problem of heat dissipation on high heat flow density electronic chip,a kind of composite wick heat column was put forward.Composite wick was formed through copper fiber sintering on orthogonal micro grooves,micro groove was processed by ploughing-extrusion and copper fiber was processed by multi tooth tool.Through analyzing and deriving of composite wick heat column structure and a variety of factors of heat transfer limit,the entrainment limit,capillary limit and boiling limit of composite wick heat column were established.It provides important theoretical basis for heat column study,and the experiment authenticates that the built theory model of composite wick heat column is correct.%针对高热流密度电子芯片散热存在的问题,提出了一种复合毛细芯热柱.复合毛细芯由正交微沟槽上烧结铜纤维得到,微沟槽采取犁切挤压的方法加工,铜纤维采用多齿刀具加工.通过对复合毛细芯热柱的结构和传热极限的各种因素进行分析推导,建立了复合毛细芯热柱的携带极限、毛细极限以及沸腾极限,为热柱的研究提供了重要的理论基础;实验验证了所建立的复合毛细芯热柱的理论模型的正确性.

  14. Enhanced reductive dechlorination in columns treated with edible oil emulsion

    Long, Cameron M.; Borden, Robert C.


    The effect of edible oil emulsion treatment on enhanced reductive dechlorination was evaluated in a 14 month laboratory column study. Experimental treatments included: (1) emulsified soybean oil and dilute HCl to inhibit biological activity; (2) emulsified oil only; (3) emulsified oil and anaerobic digester sludge; and (4) continuously feeding soluble substrate. A single application of emulsified oil was effective in generating strongly reducing, anaerobic conditions for over 14 months. PCE was rapidly reduced to cis-DCE in all three live columns. Bioaugmentation with a halorespiring enrichment culture resulted in complete dechlorination of PCE to ethene in the soluble substrate column (yeast extract and lactate). However, an additional treatment with a pulse of yeast extract and bioaugmentation culture was required to stimulate complete dechlorination in the emulsion treated columns. Once the dechlorinating population was established, the emulsion only column degraded PCE from 90-120 μM to below detection with concurrent ethene production in a 33 day contact time. The lower biodegradation rates in the emulsion treated columns compared to the soluble substrate column suggest that emulsified oil barriers may require a somewhat longer contact time for effective treatment. In the HCl inhibited column, partitioning of PCE to the retained oil substantially delayed PCE breakthrough. However, reduction of PCE to more soluble degradation products ( cis-DCE, VC and ethene) greatly reduced the impact of oil-water partitioning in live columns. There was only a small decline in the hydraulic conductivity ( K) of column #1 (low pH + emulsion, Kfinal/ Kinitial = 0.57) and column #2 (live + emulsion, Kfinal/ Kinitial = 0.73) indicating emulsion injection did not result in appreciable clogging of the clayey sand. However, K loss was greater in column #3 (sludge +emulsion, Kfinal/ Kinitial = 0.12) and column #4 (soluble substrate, Kfinal/ Kinitial = 0.03) indicating clogging due

  15. Experimental study on seismic behavior of steel reinforced concrete column with unsymmetrical steel cross-sections%非对称配钢钢骨混凝土柱抗震性能试验研究

    曾磊; 涂祥; 许成祥; 郑山锁; 吴园园


    为研究非对称配钢钢骨混凝土柱的抗震性能,进行了12个T形配钢、12个L形配钢的钢骨混凝土柱试件在低周往复荷载作用下的试验研究,试验参数为剪跨比、轴压比、体积配箍率以及是否配置拉结筋,对受力过程、破坏形态、滞回特性、骨架曲线、延性、耗能能力等进行了分析比较.结果表明,在恒定轴向荷载和水平低周往复荷载共同作用下,非对称配钢钢骨混凝土柱表现出较好的受力性能,破坏形态主要有弯曲破坏、剪切黏结破坏、剪切斜压破坏、剪切复合型破坏4种,各试件表现出较明显的正负滞回环不对称现象.剪跨比对破坏形态有较大影响,剪切复合型破坏主要发生在配有严重不对称的L形配钢的试件中;各试件的延性性能均随轴压比的增大而降低,在L形配钢试件中更为明显;增大配箍率对T形配钢试件的延性和承载力均有明显的提高,并能改善试件屈服后的耗能能力,有效改善混凝土的脆性性质,但对于剪跨比较小的L形配钢试件受力性能的改善并不明显;配置拉结筋能够提高各试件的承载能力,改善加载后期试件的承载力衰减和刚度退化,并明显增强了L形配钢试件的变形能力.%To study the seismic behavior of unsymmetrical steel reinforced concrete column, cyclic loading tests were carried out on 12 columns with T-shaped section steel and 12 columns with L-shaped section steel. The test parameters included shear span ratio, axial compression ratio, stirrup ratio and presence of cross tie. Mechanical process, failure mode, hysteretic characteristics, skeleton curves, ductility and energy dissipation ability were taken into comparison. The result indicates that unsymmetrical steel reinforced concrete column possesses good seismic performance under constant axial compression and cyclic horizontal load. The failure modes include bonding failure, shear-bond failure, shear

  16. Advanced liquefaction using coal swelling and catalyst dispersion techniques

    Curtis, C.W. (Auburn Univ., AL (United States)); Gutterman, C. (Foster Wheeler Development Corp., Livingston, NJ (United States)); Chander, S. (Pennsylvania State Univ., University Park, PA (United States))


    Research in this project centers upon developing a new approach to the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates all aspects of the coal liquefaction process including coal selection, pretreatment, coal swelling with catalyst impregnation, coal liquefaction experimentation, product recovery with characterization, alternate bottoms processing, and a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. On May 28, 1992, the Department of Energy authorized starting the experimental aspects of this projects; therefore, experimentation at Amoco started late in this quarterly report period. Research contracts with Auburn University, Pennsylvania State University, and Foster Wheeler Development Corporation were signed during June, 1992, so their work was just getting underway. Their work will be summarized in future quarterly reports. A set of coal samples were sent to Hazen Research for beneficiation. The samples were received and have been analyzed. The literature search covering coal swelling has been up-dated, and preliminary coal swelling experiments were carried out. Further swelling experimentation is underway. An up-date of the literature on the liquefaction of coal using dispersed catalysts is nearing completion; it will be included in the next quarterly report.

  17. Upgraded Coal Interest Group

    Evan Hughes


    The Upgraded Coal Interest Group (UCIG) is an EPRI 'users group' that focuses on clean, low-cost options for coal-based power generation. The UCIG covers topics that involve (1) pre-combustion processes, (2) co-firing systems and fuels, and (3) reburn using coal-derived or biomass-derived fuels. The UCIG mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired.

  18. The engineering sizing of the packed desorption column of hydrogen isotopes from Pb–17Li eutectic alloy. A rate based model using experimental mass transfer coefficients from a Melodie loop

    Linek, V., E-mail: [Prague Institute of Chemical Technology, Department of Chemical Engineering, CZ-166 28 Prague 6 (Czech Republic); Košek, L. [Research Centre Řež, CZ-250 68 Husinec-Řež (Czech Republic); Moucha, T.; Rejl, F.J.; Kordač, M.; Valenz, L.; Opletal, M. [Prague Institute of Chemical Technology, Department of Chemical Engineering, CZ-166 28 Prague 6 (Czech Republic)


    Highlights: • The model of hydrogen isotopes desorption from lead lithium alloy in packed column is presented. • Mass transfer coefficient k{sub L}a are evaluated from Alpy's Melodie loop experiments. • Packing height and efficiency of packed columns in DEMO plant for DCLL and HCLL are evaluated. • Effects of liquid phase axial dispersion, surface tension and wettability of packing are evaluated. • Effect of flow rate of the purge gas on packing height and desorption efficiency is evaluated. - Abstract: The model of the desorption of hydrogen isotopes from lead lithium alloy in a packed column is derived from the first principles using the plug flow in the liquid phase either the plug flow or ideal mixing in the gas phases. Sievert's law of non-linear equilibrium is followed. The volumetric mass transfer coefficient k{sub L}a and its dependence on the liquid metal flow rate are evaluated on the basis of the Melodie loop experiments. The presented model is used for evaluation of the minimum flow rate of the purge gas for which the concentration of the isotope in the gas leaving the column is at its highest, while the driving force of the interfacial transport of the isotope is still not reduced and the tritium desorption efficiency is therefore retained. The potential effect of the axial dispersion in the gas and liquid phase is evaluated. Highlighted are the issues of the optimum packing geometric surface area, above which the efficiency starts to decrease, and of the role of the surface tension and the contact angle with regard to the wettability of the packing. On the basis of the findings related to these factors, the Mellapak 500 Y and Mellapak packings with flat surfaces are recommended for the tests aiming to intensify the tritium desorption efficiency in the packed columns. The models were used for the engineering sizing of the packed columns in two breeding blanket concepts for the DEMO plant – utilizing DCLL (dual coolant lead lithium

  19. International perspectives on coal preparation



    The report consists of the vugraphs from the presentations which covered the following topics: Summaries of the US Department of Energy`s coal preparation research programs; Preparation trends in Russia; South African coal preparation developments; Trends in hard coal preparation in Germany; Application of coal preparation technology to oil sands extraction; Developments in coal preparation in China; and Coal preparation in Australia.

  20. 圆CFRP-钢管混凝土压弯构件滞回性能试验研究%Experimental study on hysteretic behaviors of concrete filled circular CFRP-steel tubular beam-columns

    车媛; 王庆利; 邵永波; 侯婷婷


    A total of 12 specimens were experimentally investigated to study the hysteretic behaviors of concrete filled circular CFRP-steel tubular beam-columns.The test results indicated that,CFRP can effectively provide circumferential confinement and longitudinal strengthening for the concrete filled circular steel tube,and the local bulking of the steel tube are delayed or prevented.Mid-span load-deflection hysteretic curves and moment-curvature hysteretic curves of all the specimens display perfect hysteretic behaviors.During the later loading period,there are not load bearing capacity drop for members without axial load,while there are obvious load carrying capacity drop for members with axial load.Analysis of the test results indicated that,the steel tube and its outer CFRP material can cooperate both longitudinally and circumferentially,the longitudinal strain and the circumferential strain of one same point have opposite sign,also,the deflection curves of all the members are approximately half sin wave.Calculation results showed that,the strength degradation is not obvious,axial compression ratio and strengthening factor of the longitudinal CFRP can enhance the bending strength and stiffness of the members and can delay stiffness degradation of the members,but they will decrease ductility and accumulated energy dissipation of the members,also,axial compression ratio is beneficial to seismic behaviors within certain range.%进行了12个圆CFRP-钢管混凝土压弯构件的滞回性能试验研究。试验结果表明,CFRP对圆钢管混凝土有很好的环向约束和纵向增强作用,钢管的局部屈曲得到了延缓或消除。所有试件的跨中荷载-挠度曲线和弯矩-曲率曲线均较为饱满,表现出很好的滞回性能。在加载后期,无轴压力试件的承载力无下降,而有轴压力试件的承载力明显下降。对试验结果的分析表明,钢管和CFRP在纵向和环向都可以协同工作;同一点的纵向应变和环向应

  1. Do column frits contribute to the on-column, flow-induced degradation of macromolecules?

    Striegel, André M


    Flow-induced, on-column degradation is a major hindrance to the accurate characterization of ultra-high molar mass macromolecules and colloids. This degradation is a direct result of the large shear rates which are generated within the column, which cause chain scission to occur both in the interstitial medium and, it has been postulated, at the packing particle pore boundary. An additional putative source of degradation has been the column frits, though little experimental evidence exists to either support or refute this claim. To this effect, the present experiments examine the role of the frits in the degradation of high molar mass macromolecules. Two narrow dispersity polystyrene standards, the molar mass of which differs by a factor of two, were analyzed on three different size-exclusion chromatography (SEC) columns, each with frits of different pore size, at various flow rates. In the smallest pore size column, which also contained the smallest frits and which was packed with the smallest diameter particles, the larger standard was forced to degrade by increasing the flow rate of the mobile phase. During the course of the latter portion of the study, the inlet and the outlet frits were removed from the column, in stepwise fashion. It was concluded that neither frit played any appreciable role in the degradation. Results of our studies were applied to explain previously observed degradation in ultra-high pressure liquid chromatography of polymers. The general conclusion arrived at herein is that the column frits are likely to have a secondary role (as compared to interstitial and pore boundary stresses), or no role at all, in polymer degradation for cases where the frit radius is larger than or equal to the hydraulic radius rcof the column.

  2. Coal Combustion Science

    Hardesty, D.R. (ed.); Fletcher, T.H.; Hurt, R.H.; Baxter, L.L. (Sandia National Labs., Livermore, CA (United States))


    The objective of this activity is to support the Office of Fossil Energy in executing research on coal combustion science. This activity consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency Coal Combustion Science Project. Specific tasks for this activity include: (1) coal devolatilization - the objective of this risk is to characterize the physical and chemical processes that constitute the early devolatilization phase of coal combustion as a function of coal type, heating rate, particle size and temperature, and gas phase temperature and oxidizer concentration; (2) coal char combustion -the objective of this task is to characterize the physical and chemical processes involved during coal char combustion as a function of coal type, particle size and temperature, and gas phase temperature and oxygen concentration; (3) fate of mineral matter during coal combustion - the objective of this task is to establish a quantitative understanding of the mechanisms and rates of transformation, fragmentation, and deposition of mineral matter in coal combustion environments as a function of coal type, particle size and temperature, the initial forms and distribution of mineral species in the unreacted coal, and the local gas temperature and composition.

  3. 全轻混凝土柱偏心受压性能试验研究%Experimental Study on All -lightweight Aggregate Concrete Columns Performance Under Eccentric Loading

    杨艳敏; 姚巍


    为形成集承重、轻质、节能于一体的多层建筑结构体系,推广全轻混凝土在结构体系中的应用,需对全轻混凝土柱偏心受压性能进行试验研究.试验共设计偏心受压柱6根,对比分析不同配筋、不同偏心距对偏心受压柱的破坏形态、变形特点和承载性能的影响.试验结果表明,全轻混凝土偏心受压柱破坏特征、挠曲模式及截面应变分布与普通混凝土柱基本一致,而且承载力高、延性好,全轻混凝土可作为结构材料替代普通混凝土.%In order to develop a new multi - story structural system which has a multifunction of load - bearing, lightweight and energy saving, extend the use of all - lightweight aggregate concrete in the construction. We need to do research on all - lightweight aggregate concrete columns under eccentric loading. The test design 6 columns in all. The destructed form, deformation characteristics and load - bearing properties of all - lightweight aggregate con- crete are studied by comparing different symmetrical reinforcement and different eccentricity. The test results show that the failure characteristics and flexural mode of all -lightweight aggregate concrete eccentric compression column are the same with the ordinary reinforced concrete column' s. And all - lightweight aggregate concrete columns were loaded to failure with high load - bearing capacity and good ductility. It can he the structural material instead of ordinary concrete.

  4. Experimental Study on Seismic Behavior ofSeismic-damaged Lateral Joints in CompositeFrame Consisting of CFSST Columns and SteelBeams Strengthened with Enclosed ReinforcedConcrete


    A new composite strengthening method of seismic-damaged lateral joints in composite frame consisting of Concrete-Filled SquareSteel Tubes (CFSST) columns and steel beams strengthened with enclosed Reinforced Concrete (RC) at the ends of columns andwelding steel plates at the ends of beams was presented. Based on the current design specifications, one half scaled models of 4lateral joints in composite frame consisting of CFSST columns and steel beams were designed and manufactured. One model wasoriginal control specimen, one was strengthened by enclosed RC, and the others were strengthened after pre-damage. The destructiontests under lateral cyclic load on the models were carried. The effectiveness of seismic-damaged joints strengthened with enclosedRC and the reinforcement effect on different levels of seismic damage were studied. The test results show that seismic- damagedjoints in composite frame consisting of CFSST columns and steel beams strengthened with enclosed RC meets the strongcolumn-weak beam joints requirement of seismic design, and the failure modes are of all joints are the bending failure of steel beam.The reinforcement with enclosed RC has a significant on increasing the ultimate capacity and the seismic behaviors of joints. Thestudy indicated the rehabilitated joints recover the level of their original seismic performances before seismic damage in a certainextent damage level. Based on the test data, namely the ultimate capacity, limit displacement, ductility, the energy consumptioncoefficient, limit displacementthe strengthening method of seismic-damaged joints by strengthened with enclosed RC is an effectivemethod for seismic strengthening.

  5. 裂隙煤体渗流力学特性试验研究%Experimental study on permeability of fractured coal

    罗世林; 万文; 赵延林; 唐劲舟


    煤体裂隙的存在会严重影响其渗流特性。基于裂隙中的水流运动规律,通过施加平行于裂隙面和垂直于裂隙面2种应力不同方向来研究不同荷载方向和大小对含裂隙煤体渗流特性的影响。试验结果表明:(1)当应力方向垂直于裂隙面即时,试样渗透系数会随着应力的增大而减少,且加载初期下降速率较快,之后下降速率逐渐减少,渗透系数与法向有效应力呈负指数关系。(2)当应力方向平行裂隙面时,由于试样的有效水力隙宽增大,阻碍流体流过的能力降低,因此渗透系数会相应的增大,且渗透系数与侧向有效应力呈指数关系。在试验的基础上利用专业绘图软件绘图并对2类数据拟合所建立的负指数和指数关系式能很好的反应渗透系数与有效应力的关系。%The presence of coal fractures will seriously affect its seepage characteristics.This paper,based on flow law of fracture water,studies the influence of loading direction and size on fractured coal seepage law by two kinds of axial and lateral loading.Results show that:(1 )When applying an axial stress,the specimen permeability coefficient will decrease with the increase of stress,at loading initial the rate of decline is faster, then gradually reduce the rate of decline.The relationship between the permeability coefficient and axial effective stress is negative exponential;(2)When the lateral stress is applied,due to the effective hydraulic aperture of the sample increases,the ability to hinder fluid flows is reduced.Therefore,correspondingly increases of the permeability coefficient, the relationship between permeability coefficient and lateral effective stress is exponentially.On the basis of the experiment,negative exponential and exponential relationship can be a good response relationship between permeability coefficient and effective stress which are established by using professional graphics

  6. Seismic Performance of Circular Reinforced Concrete Bridge Columns ( H ) :Evaluation of Experimental Results%圆形钢筋混凝土桥墩抗震性能(Ⅱ):试验结果评估

    李贵乾; 郑罡; 王军


    According to the failure phenomenon and test data in the orthogonal quasi-static test, the characteristics of deformation and flexural strength of circular reinforced concrete bridge columns are studied. And the displacement ductility, effective stiffness, stiffness degradation and capacity of accumulative energy dissipation to ultimate displacement state of bridge columns subjected to low-cyclic loading have been evaluated, so as to investigate the influence of factors such as shear-span ratio, axial-load ratio, and longitudinal reinforcement ratio and spiral reinforcement ratio on ductility performance of bridge columns. Finally, some useful conclusions are found out for the ductile anti-seismic design of highway bridges.%根据桥墩拟静力正交试验现象及数据结果,研究了圆形钢筋混凝土桥墩的变形特征及弯曲强度特性;并对低周反复荷载作用下桥墩的位移延性、等效刚度和刚度退化性能以及极限位移状态下累积耗能能力进行了评估,综合考察了剪跨比、轴压比、纵筋率、配箍率等因素对桥墩延性性能的影响.可为桥梁的延性抗震设计提供参考.

  7. Experimental and theoretical investigation of the pressurized coal dust furnace of RWTH Aachen; Experimentelle und theoretische Untersuchungen an der Druckkohlenstaubfeuerung der RWTH Aachen

    Renz, U. [Technische Hochschule Aachen (Germany). Lehrstuhl fuer Waermeuebertragung und Klimatechnik


    The contribution presents first results and activities funded by the BMBF, the MSWWF of Nordrhein-Westfalen, and the RWTH Aachen. The main component of the Dorsten plant is the pressure chamber which was designed and constructed in close cooperation with Messrs. L. und C. Steinmueller. The combustion chamber was installed inside the pressure vessel of the former pressurized fluidized bed steam generator of the heating power station of the RWTH Aachen. The combustion chamber is designed for a thermal power of 400 kW, corresponding to a coal mass flow of about 50 kg/h, at a pressure of 12 bar and temperatures up to 1700 degrees centigrade in melting chamber operation. It is vertical, with an inner diameter of about 400 mm, an axially movable roof burner, and four points for optical access. [Deutsch] Die Auslegung des Brenners un der Brennkammer fuer die Druckkohlenstaubfeuerung (DKSF) in Hinblick auf eine vollstaendige und stabile Verbrennung bei moeglichst geringen Emissionen an Schadgasen und Aschepartikeln war dagegen nicht primaeres Ziel des Verbundvorhabens in Dorsten. Dieses Thema wird in enger Abstimmung mit den Dorstener Aktivitaeten an einer Versuchsanlage der RWTH Aachen angegangen. Ueber die ersten Ergebnisse und die geplanten Arbeiten, die vom BMBF, vom MSWWF des Landes NRW und der RWTH Aachen gefoerdert werden, soll im Beitrag berichtet werden. Die Hauptkomponente der DKSF-Anlage ist die Druckkammer, die in enger Zusammenarbeit mit der Firma L. und C. Steinmueller ausgelegt und aufgebaut wurde. Die Aufstellung der Brennkammer im Druckbehaelter des ehemaligen Druckwirbelschicht-Dampferzeugers im Heizkraftwerk der RWTH Aachen wird aufgezeigt. Die Brennkammer ist fuer eine thermische Leistung von 400 kW, entsprechend einem Kohlenmassestrom von etwa 50 kg/h, bei einem Druck von 12 bar und fuer Temperaturen bis zu 1.700 C bei Schmelzkammerbetrieb ausgelegt. Sie ist als stehender Druckbehaelter mit einem Innendurchmesser von ca. 400 mm, einem axial

  8. Why Hexagonal Basalt Columns?

    Hofmann, Martin; Anderssohn, Robert; Bahr, Hans-Achim; Weiß, Hans-Jürgen; Nellesen, Jens


    Basalt columns with their preferably hexagonal cross sections are a fascinating example of pattern formation by crack propagation. Junctions of three propagating crack faces rearrange such that the initial right angles between them tend to approach 120°, which enables the cracks to form a pattern of regular hexagons. To promote understanding of the path on which the ideal configuration can be reached, two periodically repeatable models are presented here involving linear elastic fracture mechanics and applying the principle of maximum energy release rate. They describe the evolution of the crack pattern as a transition from rectangular start configuration to the hexagonal pattern. This is done analytically and by means of three-dimensional finite element simulation. The latter technique reproduces the curved crack path involved in this transition.

  9. Column: File Cabinet Forensics

    Simson Garfinkel


    Full Text Available Researchers can spend their time reverse engineering, performing reverse analysis, or making substantive contributions to digital forensics science. Although work in all of these areas is important, it is the scientific breakthroughs that are the most critical for addressing the challenges that we face.Reverse Engineering is the traditional bread-and-butter of digital forensics research. Companies like Microsoft and Apple deliver computational artifacts (operating systems, applications and phones to the commercial market. These artifacts are bought and used by billions. Some have evil intent, and (if society is lucky, the computers end up in the hands of law enforcement. Unfortunately the original vendors rarely provide digital forensics tools that make their systems amenable to analysis by law enforcement. Hence the need for reverse engineering.(see PDF for full column

  10. European Analytical Column

    Karlberg, B.; Grasserbauer, M.; Andersen, Jens Enevold Thaulov


    The European Analytical Column has once more invited a guest columnist to give his views on various matters related to analytical chemistry in Europe. This year, we have invited Professor Manfred Grasserbauer of the Vienna University of Technology to present some of the current challenges...... for European analytical chemistry. During the period 2002–07, Professor Grasserbauer was Director of the Institute for Environment and Sustainability, Joint Research Centre of the European Commission (EC), Ispra, Italy. There is no doubt that many challenges exist at the present time for all of us representing...... a major branch of chemistry, namely analytical chemistry. The global financial crisis is affecting all branches of chemistry, but analytical chemistry, in particular, since our discipline by tradition has many close links to industry. We have already noticed decreased industrial commitment with respect...


    Cooley, C.R.


    The patented extraction apparatus includes a column, perforated plates extending across the column, liquid pulse means connected to the column, and an imperforate spiral ribbon along the length of the column.

  12. Coal fires in China

    CHE Yao(车遥); HUANG Wen-hui(黄文辉); ZHANG Ai-yun(张爱云)


    Coal fires have a very long history in China; the oldest coal fires have being burning for many million years. Up to now more than 56 coal fires spots were distinguished. They mainly locate in West-North of China, North of China and East-North of China. About millions of tons of coal have been burned in fires every year. Xinjiang Autonomy is the most serious region in coal fires as it has 38 coal fires spots and about 6.85 million tons of coal was burned every year. Coal fires in China ignited by wildfires, spontaneous combustion and human being during mining activities. These fires have released about 0.9 million tons of gasses (including CO, CO2, SO2, NO2 CH4, CO2, H2S etc.) into the atmosphere every year, most of which are brought to the east by wind and resulting more heavier air pollution in northern China.

  13. Continuous coal processing method

    Ryason, P. R.


    A coal pump is provided in which solid coal is heated in the barrel of an extruder under pressure to a temperature at which the coal assumes plastic properties. The coal is continuously extruded, without static zones, using, for example, screw extrusion preferably without venting through a reduced diameter die to form a dispersed spray. As a result, the dispersed coal may be continuously injected into vessels or combustors at any pressure up to the maximum pressure developed in the extrusion device. The coal may be premixed with other materials such as desulfurization aids or reducible metal ores so that reactions occur, during or after conversion to its plastic state. Alternatively, the coal may be processed and caused to react after extrusion, through the die, with, for example, liquid oxidizers, whereby a coal reactor is provided.

  14. Nitrogen in Chinese coals

    Wu, D.; Lei, J.; Zheng, B.; Tang, X.; Wang, M.; Hu, Jiawen; Li, S.; Wang, B.; Finkelman, R.B.


    Three hundred and six coal samples were taken from main coal mines of twenty-six provinces, autonomous regions, and municipalities in China, according to the resource distribution and coal-forming periods as well as the coal ranks and coal yields. Nitrogen was determined by using the Kjeldahl method at U. S. Geological Survey (USGS), which exhibit a normal frequency distribution. The nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%. Nitrogen in coal exists primarily in organic form. There is a slight positive relationship between nitrogen content and coal ranking. ?? 2011 Science Press, Institute of Geochemistry, CAS and Springer Berlin Heidelberg.

  15. Coal worker's pneumoconiosis

    ... this page: // Coal worker's pneumoconiosis To use the sharing features on this page, please enable JavaScript. Coal worker's pneumoconiosis is a lung disease that results ...

  16. Fluidized coal combustion

    Moynihan, P. I.; Young, D. L.


    Fluidized-bed coal combustion process, in which pulverized coal and limestone are burned in presence of forced air, may lead to efficient, reliable boilers with low sulfur dioxide and nitrogen dioxide emissions.

  17. TENORM: Coal Combustion Residuals

    Burning coal in boilers to create steam for power generation and industrial applications produces a number of combustion residuals. Naturally radioactive materials that were in the coal mostly end up in fly ash, bottom ash and boiler slag.

  18. Chemicals from coal

    Harold A. Wittcoff; Bryan G. Reuben; Jeffrey S. Plotkin


    This chapter contains sections titled: Chemicals from Coke Oven Distillate; The Fischer-Tropsch Reaction; Coal Hydrogenation; Substitute Natural Gas (SNG); Synthesis Gas Technology; Calcium Carbide; Coal and the Environment; and Notes and References


    Theodore T. Tsotsis; Muhammad Sahimi; Ian A. Webster


    It was the purpose of the project described here to carry out careful and detailed investigations of petroleum and coal asphaltene transport through model porous systems under a broad range of temperature conditions. The experimental studies were to be coupled with detailed, in-depth statistical and molecular dynamics models intended to provide a fundamental understanding of the overall transport mechanisms and a more accurate concept of the asphaltene structure. The following discussion describes some of our accomplishments.




    carried out during August at the Advanced Photon Source (APS), the new synchrotron facility at Argonne National Laboratory, Chicago, IL. Further analysis of small-scale combustion experiments conducted at PSI in Phase I was completed this quarter. The results of these experiments for the first time suggest almost complete vaporization of certain trace elements (Se, Zn) from coal combustion in the flame zone, in accordance with theoretical equilibrium predictions. Other elements (As, Sb, Cr) appeared considerably less volatile and may react with constituents in the bulk ash at combustion temperatures. The combustion section of the University of Arizona's Downflow Combustor was completely rebuilt. The University of Utah worked on setting up EPA Method 26A to give the capability to measure chlorine in flue gas. The chlorine kinetic calculations performed as part of the Phase I program were found to have an error in the initial conditions. Therefore, the calculations were re-done this quarter with the correct starting conditions. Development of a quasi-empirical emissions model based on reported emissions of particulate matter from field measurements was continued this quarter. As a first step in developing the ToPEM, we developed a sub-model that calculates the evaporation of major elements (Na, K, Fe, Si, Al, Ca and Mg) from both inherent and extraneous minerals of coal. During this quarter, this sub-model was included into EMAF, which formed the ToPEM. Experimental data from the Phase I program were used to test and modify the sub-model and the ToPEM.

  1. Experimental Study on Seismic Behavior of Composite Core Walls With Steel Tube-reinforced Concrete Columns%钢管混凝土叠合柱边框组合核心筒抗震性能试验研究

    董宏英; 耿海霞; 张建伟; 曹万林; 杨信强


    为了比较带钢管混凝土叠合柱边框组合核心筒与带钢管混凝土边框组合核心筒的抗震性能,进行了1个钢管混凝土叠合柱边框组合核心筒模型和1个钢管混凝土柱边框组合核心筒模型的低周反复荷载试验研究,2个模型均按1/6缩尺.在试验基础上,分析比较了2个核心筒的承载力、延性、滞回特性、刚度及其衰减过程、耗能能力和破坏特征.研究表明,钢管混凝土叠合柱边框组合核心筒比钢管混凝土柱边框组合核心筒的抗震性能显著提高;承载力简化计算模型的计算结果与实测结果符合较好.%The cyclic tests are performed in order to compare the seismic behavior of two 1/6 scale composite core walls with different columns, one with concrete filled steel tube columns and the other with steel tubereinforced concrete columns. Based on the experiment, load-carrying capacity, ductility, hysteretic property, stiffness and degradation, energy dissipation and damage characteristics of the two specimens are compared. It is shown that the seismic behavior of the core walls with steel tube-reinforced concrete columns is better than those with concrete filled steel tube columns. The mechanical model for calculating load-carrying capacity of the new RC composite core walls is proposed. And the calculating results agreed well with the results from the experiments.

  2. 配置HRB500钢筋的混凝土L形柱滞回性能试验研究%An experimental research on hysteretic behavior of HRB500 reinforcement concrete L-shaped columns

    戎贤; 巩雪娇; 李艳艳


    为推广HRB500钢筋在异形柱结构中的应用及研究L形柱的滞回性能,对不同轴压比与配箍率的配置HRB500钢筋的混凝土L形柱试件进行低周往复加载试验,对比分析试件的破坏特征、滞回曲线、骨架曲线和刚度退化曲线,研究配箍率和轴压比对配置HRB500钢筋的混凝土L形柱滞回性能的影响.研究表明:减小轴压比和增加配箍率,可以改善试件的破坏特征和试件的滞回特性.减小轴压比还可以减缓试件的刚度退化.研究结果为配置HRB500钢筋的混凝土L形柱结构设计提供参考.%The HRB500 reinforcement concrete L-shaped column with various axial compression ratios and stirrup ratios was tested in low -cyclic- loading experiments in order to promote application of HRB500 steel bars in specially shaped column structure and research the hysteretic behavior of L-specially shaped columns. The result of damage characteristic, hysteretic characteristic, skeleton curve and the rigidity degradation was analyzed. The effects on hysteretic behavior of HRB500 reinforcement concrete L-shaped column were analyzed such as the axial compression ratio and stirrup ratios. It shows that the damage characteristic and the hysteretic characteristic of specimens are improved with the decrease of axial compression ratio and increase of stirrup ratios. The rigidity degradation becomes slow with the increase of axial compression ratio. The conclusions of HRB500 reinforcement concrete L-shaped column can be references for structural design.

  3. 不同剪跨比下型钢再生混凝土柱抗震性能试验研究%Experimental study on seismic behavior of steel reinforced recycled concrete column under different shear-span ratios

    薛建阳; 马辉


    In order to investigate the failure patterns and seismic performance of steel reinforced recycled concrete columns,four column specimens with different shear span ratio of steel reinforced recycled concrete were tested under low cyclic reversed loading.The failure process and patterns were observed.The mechanical behaviors,such as load-displacement hysteretic loops and skeleton curves,load carrying capacity,ductility,energy dissipation capacity and stiffness degradation of steel reinforced recycled concrete columns were analyzed.Test research results show that the shear diagonal compression failure,shear-bending failure and bending failure are the main patterns of steel reinforced recycled concrete columns.The load carrying capacity of specimens reduces with the increase of shearspan ratio,but the load-displacement hysteretic loops are plumper and the descending of load carrying capacity is relatively slow.It also shows the stiffness degradation rate is slower and the ductility or energy dissipation capacity is greater with the increase of shear span ratio.Overall,the steel reinforced recycled concrete columns with high shear-span ratio behave well in seismic performance.It can be used in the practical engineering.%为研究型钢再生混凝土柱的破坏形态和抗震性能,进行了4个不同剪跨比的型钢再生混凝土柱低周反复荷载试验,观察了其受力过程及破坏形态,分析了剪跨比对柱的滞回曲线、骨架曲线、承载力、延性、耗能及刚度退化等力学性能的影响.研究结果表明:根据剪跨比的不同,型钢再生混凝土柱的破坏形态主要为剪切斜压破坏、弯剪破坏以及弯曲破坏.随着剪跨比的增大,试件水平承载力降低,但滞回曲线愈加饱满,承载力下降越缓慢,刚度退化速率越慢,延性及耗能越好.总体上看,剪跨比较大试件的抗震性能较好,可以用于实际工程.

  4. 钢套法加固方钢管混凝土柱抗震性能试验研究%Experimental research on seismic behavior of strengthened CFSST columns steel sleeve method

    杨炳; 许成祥; 赵斌; 付晨曦; 彭威


    针对方钢管混凝土柱加固后的抗震性能进行了6根柱的低周反复荷载破坏试验,研究了外套钢套法和外包钢套法两种加固方法以及钢套壁厚、施焊和加固高度对加固效果的影响,分析了相应的加固机理。通过对试件的滞回曲线、骨架曲线、延性、耗能能力、承载力及刚度退化系数等参数的分析可知:钢套法合理加固保证了混凝土柱“强剪弱弯”抗震延性设计目标,其破坏形态均表现为压弯破坏;外套钢套法加固提高柱的承载力作用有限,但极大提高了混凝土柱的延性性能,使其抗震性能明显提高;外包钢套法加固显著提高了混凝土柱的承载力、刚度,使其延性性能有所改善,抗震性能显著提高。%In order to study the seismic behavior of concrete-filled square steel tubular ( CFSST ) column after reinforcement, a destruction test was carried out on six specimens under lateral cyclic loading. The influences of steel jacket and enveloped steel methods, wall thickness of the enveloped steel and welding and strengthening height on the reinforcement effect were studied, and their rein-forcement mechanism was analyzed. From the test data, the hysteretic loops, skeleton curves, duc-tility, dissipative ability, ultimate strength and stiffness degradation etc. , a conclusion was drawn:the CFSST column strengthened by the steel sleeve method meets the strong shear weak bending re-quirements in seismic design, and the failure modes of all columns are compression bending failure. The steel jacket method has notable influence on the ductility and the seismic performance of col-umns, but leads to limited increment to the ultimate strength. The enveloped steel method has sig-nificant improvements on the strength, the stiffness and all aspects of seismic performance of col-umns.

  5. Coal Extraction - Environmental Prediction

    Cecil, C. Blaine; Tewalt, Susan J.


    Coal from the Appalachian region has supplied energy to the Nation for more than 200 years. Appalachian coal fueled America through a civil war and helped win two world wars. Appalachian coal has also provided fuel for keeping America warm in the winter and cool in the summer and has served as the basis for the steel, automobile, organic chemicals, chlorine, and aluminum industries. These benefits have not come without environmental costs, however. Coal extraction and utilization have had significant environmental impacts.

  6. Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications

    Smit, Frank J; Schields, Gene L; Jha, Mehesh C; Moro, Nick


    The ash in six common bituminous coals, Taggart, Winifrede, Elkhorn No. 3, Indiana VII, Sunnyside and Hiawatha, could be liberated by fine grinding to allow preparation of clean coal meeting premium fuel specifications (< 1- 2 lb/ MBtu ash and <0.6 lb/ MBtu sulfur) by laboratory and bench- scale column flotation or selective agglomeration. Over 2,100 tons of coal were cleaned in the PDU at feed rates between 2,500 and 6,000 lb/ h by Microcel™ column flotation and by selective agglomeration using recycled heptane as the bridging liquid. Parametric testing of each process and 72- hr productions runs were completed on each of the three test coals. The following results were achieved after optimization of the operating parameters: The primary objective was to develop the design base for commercial fine coal cleaning facilities for producing ultra- clean coals which can be converted into coal-water slurry premium fuel. The coal cleaning technologies to be developed were advanced column flotation and selective agglomeration, and the goal was to produce fuel meeting the following specifications.




    Experiments were carried out in bubble columns for a number of liquids at pressures between 0.1 and 2.0 MPa for two column sizes. Based on the experimental results as well as extensive literature data, the extent of the effect column dimensions have on gas holdup were determined, both at low and hig

  8. 薄壁波纹钢管混凝土柱滞回性能试验研究%Experimental study on the hysteretic behaviors of thin-walled corrugated concrete-filled steel tube column

    高剑平; 吴永根; 霍静思


    近年来,薄壁钢管混凝土柱由于其良好的力学性能和施工性能在各类建筑结构和桥梁上得到了广泛应用,但震害表明,普通薄壁钢管混凝土柱抗局部屈曲能力和屈曲后抗震性能较差.提出了一种薄壁波纹钢管混凝土柱,为了初步探索其抗震性能,以轴压比和截面形式为主要参数,进行了2根薄壁波纹钢管混凝土柱和2根普通薄壁钢管混凝土柱低周反复加载试验研究.主要结论如下:在轴压比相同的情况下,薄壁波纹钢管混凝土柱的滞回曲线明显要比其它两种截面形式的饱满;在相同位移时,薄壁波纹钢管混凝土柱的耗能能力明显好于方形和圆形的.三种截面形式的延性较接近且延性系数均超过3,且强度退化和刚度退化趋势和程度基本一致.综合分析,薄壁波纹钢管混凝土柱抗震性能较之圆、方形薄壁钢管混凝土柱的相当或稍好.研究结果可供城市高架桥的分析与设计参考.%In recent years, thin-walled concrete-filled steel tube column ha been widely used in many types of building structures and bridges, owing to its good mechanical properties and construction performance. However, the local buckling capacity and post-buckling seismic capacity of common thin-walled concrete-filled steel tube column are poor. A new-style thin-walled corrugated concrete-filled steel tube column was proposed. A low cyclic loading test was conducted to study its seismic performance with axial-compression ratio and section form as the main parameters. The main conclusions are as follows; the hysteresis loops of thin-walled corrugated steel concrete column are fuller than those of the other two section forms under the same axial-compression ratio. The dissipation energy capacity of thin-walled corrugated steel concrete column is better than that of square and circle under the same displacement condition. The ductility coefficients of the three section forms are close and all

  9. Considerations on coal gasification

    Franzen, J. E.


    Commercial processes for the gasification of coal with oxygen are discussed. The Koppers-Totzek process for the gasification of coal dust entrained in a stream of gasifying agents is described in particular detail. The outlook for future applications of coal gasification is presented.

  10. Prediction of coal hydrophobicity

    Labuschagne, B.C.J. [Council for Scientific and Industrial Research, Pretoria (South Africa). Div. of Energy Technology; Wheelock, T.D.; Guo, R.K.; David, H.T. [Iowa State Univ. of Science and Technology, Ames, IA (United States); Markuszewski, R. [Ames Lab., IA (United States)


    Many coals exhibit a certain degree of native hydrophobicity. The more hydrophobic coals (the higher-rank coals) are easily beneficiated by froth flotation or oil agglomeration, while the more hydrophilic coals (the lower-rank coals) are floated or agglomerated with difficulty. Coals of different ranks and often even of the same rank sometimes differ greatly in hydrophobicity as measured by contact angle or natural floatability. Although the degree of hydrophobicity of a coal is related to its rank and has been correlated with other surface properties of the coal , the known information is still not sufficient to allow a good estimation to be made of the hydrophobicity of a given coal and does not explain the variation of coal hydrophobicity as a function of rank. A statistical analysis of previously published data, as well as newly acquired data, shows that coal hydrophobicity correlates better with moisture content than with carbon content, and better with the moisture/carbon molar ratio than with the hydrogen/carbon or oxygen/carbon atomic ratios. These findings indicate that there is a strong association between hydrophobicity and coal moisture content.

  11. Coal production 1989


    Coal Production 1989 provides comprehensive information about US coal production, the number of mines, prices, productivity, employment, reserves, and stocks to a wide audience including Congress, federal and state agencies, the coal industry, and the general public. 7 figs., 43 tabs.

  12. Reducing axial mixing in flotation columns

    Al Taweel, A.M.; Ramadan, A.M. [Technical Univ. of Nova Scotia, Halifax (Canada). Chemical Engineering Dept.; Moharam, M.R.; Hassan, T.A. [Al Azhar Univ., Cairo (Egypt); El Mofty, S.M. [Cairo Univ., Giza (Egypt)


    The axial mixing characteristics of a pilot-scale flotation column were investigated with the objective of identifying means to mitigate the extent of axial mixing that adversely affects its grade/recovery performance. A wide range of design and operating conditions wa investigated and the experimental results, obtained using the dynamic response method, were analyzed using three axial mixing models. The dynamic response of the column can best be described using the axial dispersion model. The results obtained suggest that the value of the axial dispersion coefficient, E{sub L}, can be significantly reduced by judicial selection of hydrodynamic conditions and/or the use of column inserts that suppress the onset of hydrodynamic instabilities inherent to the operation of conventional flotation columns. Up to 40% reduction in the value of E{sub L} was thus obtained by using spargers that produce more uniform bubble sizes, while up to 30% reductions were obtained by controlling the residual frother concentration. 33 refs., 7 figs.

  13. Experimental and Numerical Study on Ultra-Low Concentration Coal Bed Methane Combustion in a Fluidized Bed%超低浓度煤层气在流化床中燃烧的实验和数值研究

    杨仲卿; 张力; 唐强; 蒲舸


    超低浓度煤层气由于甲烷含量低、浓度变化大而较难加以利用。采用实验和数值模拟的方法,研究了超低浓度煤层气在流化床中的燃烧,分析了床层温度、甲烷体积浓度,流化风速对甲烷燃烧效率的影响,并用数学模型预测了甲烷沿床层高度方向的分布。研究表明,数学模型和实验数据吻合较好。床层温度是煤层气燃烧反应的关键因素,甲烷的转化率随着床层温度的升高而增加。燃烧反应主要发生在乳化相,且主要集中在床层的下部。甲烷的转化率随着流化风速和煤层气中甲烷浓度的增加而减少。在床层温度为650℃时,甲烷浓度低于1%的煤层气的甲烷转化率均大于93%。增加床层高度可使甲烷完全转化。%The ultra-low concentration coal bed methane is difficult to utilize due to its low methane content and fluctuated concentration. Coal bed methane combustion in a fluidized bed was studied experimentally and numerically. The effects of bed temperature, methane volumetric concentration and fluidized velocity on methane conversion were analyzed. The methane profile along bed height was predicted with the mathematical model. The results show that the model compares reasonably well with experimental data. Bed temperature is a major factor on combustion. And the methane conversion increases with the rising bed temperature. The combustion reaction is mainly occurred in the emulsion phase and at lower part of the bed. The methane conversion decreases with the increasing fluidized velocity and inlet methane concentration. When the bed temperature is 650℃ and methane concentration is less than 1%, the conversion is greater than 93%. More methane can be consumed when the bed height is increasing.

  14. Compact electron beam focusing column

    Persaud, Arun; Leung, Ka-Ngo; Reijonen, Jani


    A novel design for an electron beam focusing column has been developed at LBNL. The design is based on a low-energy spread multicusp plasma source which is used as a cathode for electron beam production. The focusing column is 10 mm in length. The electron beam is focused by means of electrostatic fields. The column is designed for a maximum voltage of 50 kV. Simulations of the electron trajectories have been performed by using the 2-D simulation code IGUN and EGUN. The electron temperature has also been incorporated into the simulations. The electron beam simulations, column design and fabrication will be discussed in this presentation.

  15. Lattice approaches to packed column simulations


    This work presents a review of the findings into the ability of a digitally based particle packing algorithm, called DigiPac, to predict bed structure in a variety of packed columns, for a range of generic pellet shapes frequently used in the chemical and process engineering industries.Resulting macroscopic properties are compared with experimental data derived from both invasive and non-destructive measurement techniques.Additionally, fluid velocity distributions, through samples of the resulting bed structures, are analysed using lattice Boltzmann method (LBM) simulations and are compared against experimental data from the literature.

  16. Computer animation of hot spot development in bulk coal as an aid for training coal miners

    Hancock, M.; Kizil, M.S.; Beamish, B.B. [University of Queensland, Brisbane, Qld. (Australia). School of Engineering


    The processes that take place during the development of a heating are difficult to visualise. Bulk coal self-heating tests at The University of Queensland (UQ) using a two-metre column are providing graphic evidence of the stages that occur during a heating. Data obtained from these tests, both temperature and corresponding off-gas evolution can be transformed into what is effectively a video-replay of the heating event. This is achieved by loading both sets of data into a newly developed animation package called Hotspot. The resulting animation is ideal for spontaneous combustion training purposes as the viewer can readily identify the different hot spot stages and corresponding off-gas signatures. Colour coding of the coal temperature, as the hot spot forms, highlights its location in the coal pile and shows its ability to migrate upwind. An added benefit of the package is that once a mine has been tested in the UQ two-metre column, there is a permanent record of that particular coals performance for mine personnel to view. 7 refs., 9 figs., 1 tab.

  17. Reactive-transport modeling of fly ash-wate-brines interactions from laboratory-scale column studies

    Mbugua, John M.; Catherine Ngila, J.; Kindness, Andrew; Demlie, Molla

    Dynamic leaching tests are important studies that provide more insights into time-dependent leaching mechanisms of any given solid waste. Hydrogeochemical modeling using PHREEQC was applied for column modeling of two ash recipes and brines generated from South African coal utility plants, Sasol and Eskom. The modeling results were part of a larger ash-brine study aimed at acquiring knowledge on (i) quantification and characterization of the products formed when ash is in contact with wate-brines in different scenarios, (ii) the mineralogical changes associated with wate-brine-ash interactions over time, (iii) species concentration, and (iv) leaching and transport controlling factors. The column modeling was successfully identified and quantified as important reactive mineralogical phases controlling major, minor and trace elements' release. The pH of the solution was found to be a very important controlling factor in leaching chemistry. The highest mineralogical transformation took place in the first 10 days of ash contact with either water or brines, and within 0.1 m from the column inflow. Many of the major and trace elements Ca, Mg, Na, K, Sr, S(VI), Fe, are leached easily into water systems and their concentration fronts were high at the beginning (within 0.1 m from the column inflow and within the first 10 days) upon contact with the liquid phase. However, their concentration decreased with time until a steady state was reached. Modeling results also revealed that geochemical reactions taking place during ash-wate-brine interactions does affect the porosity of the ash, whereas the leaching processes lead to increased porosity. Besides supporting experimental data, modeling results gave predictive insights on leaching of elements which may directly impact on the environment, particularly ground water. These predictions will help develop scenarios and offer potential guide for future sustainable waste management practices as a way of addressing the co

  18. Incipient motion of gravel and coal beds

    Subhasish Dey; Uddaraju V Raju


    An experimental study on incipient motion of gravel and coal beds under unidirectional steady-uniform flow is presented. Experiments were carried out in a flume with various sizes of gravel and coal samples. The critical bed shear stresses for the experimental runs determined using side-wall correction show considerable disagreement with the standard curves. The characteristic parameters affecting the incipient motion of particles in rough-turbulent regime, identified based on physical reasoning and dimensional analysis, are the Shields parameter, particle Froude number, non-dimensional particle diameter and non-dimensional flow depth. Equations of critical bed shear stress for the initial movement of gravel and coal beds were obtained using experimental data. The method of application of critical bed shear stress equations is also mentioned.

  19. Design, testing, and simulation of microscale gas chromatography columns

    Hudson, M.L.; Kottenstette, R.; Matzke, C.M.; Frye-Mason, G.C.; Shollenberger, K.A.; Adkins, D.R.; Wong, C.C.


    A microscale gas chromatography column is one component in a microscale chemistry laboratory for detecting chemical agents. Several columns were fabricated using the Bosch etch process which allows deep, high aspect ratio channels of rectangular cross-section. A design tool, based on analytical models, was developed to evaluate the effects of operating conditions and column specifications on separation resolution and time. The effects of slip flow, channel configuration, and cross-sectional shape were included to evaluate the differences between conventional round, straight columns and the microscale rectangular, spiral columns. Experimental data were obtained and compared with the predicted flowrates and theoretical number of plates. The design tool was then employed to select more optimum channel dimensions and operating conditions for high resolution separations.

  20. Engineering development of advanced physical fine coal cleaning for premium fuel applications. Quarterly report, April 1--June 30, 1997

    Moro, N.; Shields, G.L.; Smit, F.J.; Jha, M.C.


    The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction, and operation of a 2 t/hr process development unit (PDU). Accomplishments during the quarter are described on the following tasks and subtasks: Development of near-term applications (engineering development and dewatering studies); Engineering development of selective agglomeration (bench-scale testing and process scale-up); PDU and advanced column flotation module (coal selection and procurement and advanced flotation topical report); Selective agglomeration module (module operation and clean coal production with Hiawatha, Taggart, and Indiana 7 coals); Disposition of the PDU; and Project final report. Plans for next quarter are discussed and agglomeration results of the three tested coals are presented.

  1. Survey and evaluation of current and potential coal beneficiation processes

    Singh, S. P.N.; Peterson, G. R.


    Coal beneficiation is a generic term used for processes that prepare run-of-mine coal for specific end uses. It is also referred to as coal preparation or coal cleaning and is a means of reducing the sulfur and the ash contents of coal. Information is presented regarding current and potential coal beneficiation processes. Several of the processes reviewed, though not yet commercial, are at various stages of experimental development. Process descriptions are provided for these processes commensurate with the extent of information and time available to perform the evaluation of these processes. Conceptual process designs, preliminary cost estimates, and economic evaluations are provided for the more advanced (from a process development hierarchy viewpoint) processes based on production levels of 1500 and 15,000 tons/day (maf) of cleaned product coal. Economic evaluations of the coal preparation plants are conducted for several project financing schemes and at 12 and 15% annual after-tax rates of return on equity capital. A 9% annual interest rate is used on the debt fraction of the plant capital. Cleaned product coal prices are determined using the discounted cash flow procedure. The study is intended to provide information on publicly known coal beneficiation processes and to indicate the relative costs of various coal beneficiation processes. Because of severe timeconstraints, several potential coal beneficiation processes are not evaluated in great detail. It is recommended that an additional study be conducted to complement this study and to more fully appreciate the potentially significant role of coal beneficiation in the clean burning of coal.

  2. Experimental research on combined pile composite foundation with vibro-replacement stone columns and CFG piles%振冲碎石桩与CFG桩组合桩型复合地基试验研究

    李继才; 丛建; 曹军; 余博闻


    The vibro-replacement stone columns are mainly used to treat the shallow-layer soil and generate one kind of composite foundation in order to reinforce the bearing capacity of the foundation,decrease the settlement and eliminate the sand liquefaction.The CFG pile is settled at the centroid of four gravel columns and the tip of the CFG pile is deep in the hard layer,which plays an important role in controlling the bearing capacity and the displacement of the composite foundation.This paper researches the composite foundation consisting of the vibro-replacement stone columns and the CFG piles before and after the treatment by the static sounding test,the dynamic sounding test and the static load test.The results indicate that the vibro-replacement stone column in the combinedpile composite foundation largely increases the bearing capacity of the single CFG pile and the soil layer,and the smaller the distance between piles,the greater the strengthening effects will be.%振冲碎石桩主要加固浅层地基,与桩间土构成复合地基,使地基承载力提高、变形减少,并可消除砂土层的液化;CFG桩布置在4根碎石桩的形心,桩端置于相对硬层,对复合地基的承载力和变形起控制作用.对某工程试验区振冲碎石桩与CFG桩组合桩型复合地基加固前后静力触探、动力触探和静载荷试验等进行研究,结果表明组合桩型复合地基中的碎石桩较大程度地提高了CFG桩的单桩承载力和地基承载力,桩距越小,加固效果越好.

  3. 应用聚偏氟乙烯-丝氨酸进行血液灌流治疗脓毒症的实验研究%Effects of direct hemoperfusion with polyvinylidene difluoride-serine column in experimental sepsis

    李宁; 周焕玉; 张媛媛; 周岩; 徐放


    Objective To study the effect of direct hemoperfusion (HP) with polyvinylidene difluoride scrine (PVDF Scr) column on hemodynamics in pigs with septic shock. Methods Sixteen male family pigs were injected endotoxin [1μg/(kg·h) intravenously] for 4 hours and randomly assigned to either group in ~ 8 per group): HP with PVDF-Ser column for 2 hours after endotoxin (E group); HP with empty column for 2 hours (C group). Blood samples were drawn before and after endotoxin injection and IIP for the measurement of plasma endotoxin and cytokines concentrations. The changes of hemody namics were observed at the same time. Results The concentrations of cytokines in E group after HP were significantly lower thart in C group, and the hemodynamic parameters were improved remarkably in E group after HP compared to in C group. Conclusion Direct HP with PVDF-Ser column effectively regulate the inflammatory responses and recovere hemodynamics in septic shock.%目的 研究聚偏氟乙烯(polyvinylidene difluoride,PVDF)-丝氨酸(serine,Ser)吸附膜用于血液灌流对感染性休克的血流动力学影响.方法 雄性家猪16只,给予内毒素1μg/(kg·h)静脉泵入4 h复制感染性休克模型.随机分为实验组(E组,8只),应用PVDF-Ser吸附膜进行血液灌流2 h,对照组(C组,8只)应用空白灌流器进行血液灌流2 h.分别于注射内毒素前后和血液灌流前后测定血浆内毒素和细胞因子水平,监测血流动力学指标变化.结果 E组血液灌流后细胞因子水平显著低于C组,血流动力学参数较C组明显改善.结论 应用PVDF-Ser吸附膜进行血液灌流,可有效调控感染性休克的炎症反应,纠正血流动力学紊乱.

  4. Experimental study on restoring force characteristics of steel column base with wedge device%带楔块装置钢柱脚恢复力特性试验

    雷劲松; 姚勇; 卢学松; 高松隆夫; 邹银生


    A new isolation device was designed to avoid damage of steel exposed-column base in earthquake,which consists of a wedge compressed by a spring and a counter-wedge.By the plastic elongation of the anchor bolt,the deformation of the spring and the slip of the wedge,the device can effectively dissipate the earthquake energy and control the damage of the structure.Dynamic cyclic test was performed to study the hysteretic behaviors of steel exposed-column base with and without the device.The results show that the ordinary column base is observed to be slip-type due to a gap between the nut of the anchor bolt and the base plate,caused by the plastic elongation of the anchor bolt.The new isolation column base is observed to be non-slip-type due to the gap which can be eliminated by use of the new device.Based on test results,a new non-slip-type hysteretic model is proposed.The results show that this device provides a better seismic performance and can be used conveniently.%为避免钢结构露出型柱脚在地震中发生破坏,研究一种新的减震装置。该装置通过楔块滑动、弹簧变形和螺杆的塑性伸长来控制柱脚位移,同时消耗地震能量,达到消能减震的效果。采用方形空心钢管柱,分别对普通螺栓柱脚和带减震装置的柱脚进行低周往复加载试验,研究其恢复力特性。试验表明:普通螺栓连接的柱脚呈滑移型滞回特征;由于弹簧恢复和楔块切入,新型柱脚连接每次加载卸载均以原点为始终,呈无滑移型滞回特征。根据试验结果,得到了带楔块装置钢柱脚的无滑移型恢复力模型。研究结果表明,无滑移型减震连接的钢柱脚具有良好的抗震性能且简单易用

  5. 损伤型钢混凝土异形柱框架抗震性能试验研究%Experimental study on seismic behaviors of damaged steel reinforced concrete frame with special-shaped columns

    刘祖强; 薛建阳; 赵鸿铁; 隋


    In order to investigate the seismic behaviors of damaged Steel Reinforced Concrete (SRC) frames with special-shaped columns,pseudo-dynamic test was conducted on a model of two-bay and three-story.The mechanical behaviors,such as dynamic response,hysteretic property and stiffness were analyzed.Test results show that when the damaged SRC frame with special-shaped columns experiences earthquake again,the damage starts at the heavily damaged position.The hysteretic loops are full,and the capacity of bearing,energy dissipation and collapse resistance are high.The stiffness is small,so that the story drift is large when the earthquake action is not strong.The damaged SRC frame with special-shaped columns,whose damaged index is not greater than 0.8,does not collapse under the 8 intensity intermediate action.This study can provide reference for the application of SRC frame with special-shaped columns in practical engineering.%为研究损伤型钢混凝土(SRC)异形柱框架的抗震性能,对1榀两跨三层的框架模型进行拟动力试验,分析该结构在水平地震作用下的动力响应、滞回特性、刚度等性能.结果表明:损伤SRC异形柱框架再次遭受地震作用时,首先从损伤严重的部位开始破坏;滞回曲线较为饱满,具有一定的承载能力、耗能能力和抗倒塌能力;刚度较小,当地震作用不大时层间变形较大.损伤指标不大于0.8的SRC异形柱框架,能够承受8度基本烈度的地震作用而不发生倒塌.研究可为SRC异形柱框架的工程应用提供参考.

  6. 钢管再生混凝土长柱轴压受力性能试验研究%Experimental research on mechanical behavior of recycled aggregate concrete filled circular steel tubular long columns under axial compression loading

    吴炎海; 方映平; 冯文贤; 蔡杨


    Axial static loading test was carried out on 6 recycled aggregate concrete filled circular steel tubular long columns. The whole loading process and failure modes were observed,and the curves of specimens about load-deformation and load-strain were plotted. The influences of the test parameters namely slenderness ratio and confine-ment index on deformation and the bearing capacities of specimens were analyzed. By domestic and foreign relevant specifications,the ultimate bearing capacity of the specimens were calculated and compared with the measured val-ues. The results indicated that the failure process of recycled aggregate concrete filled steel tubular long columns un-der axial compression includes elastic stage,elastic-plastic stage and plastic stage,and all the failure modes are elas-tic-plastic instability;Both the slenderness ratio and confinement index affect the mechanical performance of recy-cled aggregate concrete filled steel tubular long columns under axial loading,and the confinement index is more ob-vious;Finally,the calculation and design method of recycled aggregate filled steel tubular long columns under axial loading were proposed.%进行6根圆钢管再生混凝土长柱轴压的静力加载试验,观察试件受力的全过程和破坏形态,绘制出各试件的荷载-变形和荷载-应变关系曲线,分析长径比和套箍系数2个变化参数对试件变形和承载力的影响规律,采用国内外相关规程计算各试件的极限承载力并与实测值进行对比。结果表明:钢管再生混凝土轴压长柱受力过程经历了弹性阶段、弹塑性阶段和塑性下降阶段,均为弹塑性失稳破坏;长径比和套箍系数对钢管再生混凝土轴压长柱的受力性能均有影响,其中套箍系数影响较大;最后对于钢管再生混凝土长柱轴压的承载力计算及构件的设计提出建议。

  7. Clean and Secure Energy from Coal

    Smith, Philip; Davies, Lincoln; Kelly, Kerry; Lighty, JoAnn; Reitze, Arnold; Silcox, Geoffrey; Uchitel, Kirsten; Wendt, Jost; Whitty, Kevin


    The University of Utah, through their Institute for Clean and Secure Energy (ICSE), performed research to utilize the vast energy stored in our domestic coal resources and to do so in a manner that will capture CO2 from combustion from stationary power generation. The research was organized around the theme of validation and uncertainty quantification (V/UQ) through tightly coupled simulation and experimental designs and through the integration of legal, environment, economics and policy issues. The project included the following tasks: • Oxy-Coal Combustion – To ultimately produce predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. • High-Pressure, Entrained-Flow Coal Gasification – To ultimately provide a simulation tool for industrial entrained-flow integrated gasification combined cycle (IGCC) gasifier with quantified uncertainty. • Chemical Looping Combustion (CLC) – To develop a new carbon-capture technology for coal through CLC and to transfer this technology to industry through a numerical simulation tool with quantified uncertainty bounds. • Underground Coal Thermal Treatment – To explore the potential for creating new in-situ technologies for production of synthetic natural gas (SNG) from deep coal deposits and to demonstrate this in a new laboratory-scale reactor. • Mercury Control – To understand the effect of oxy-firing on the fate of mercury. • Environmental, Legal, and Policy Issues – To address the legal and policy issues associated with carbon management strategies in order to assess the appropriate role of these technologies in our evolving national energy portfolio. • Validation/Uncertainty Quantification for Large Eddy Simulations of the Heat Flux in the Tangentially Fired Oxy-Coal Alstom Boiler Simulation Facility – To produce predictive capability with quantified uncertainty bounds for the heat flux in commercial-scale, tangentially fired, oxy-coal boilers.

  8. Control of pyrite surface chemistry in physical coal cleaning. Final report

    Luttrell, G.H.; Yoon, R.H.; Richardson, P.E.


    In Part I, Surface Chemistry of Coal Pyrite the mechanisms responsible for the inefficient rejection of coal pyrite were investigated using a number of experimental techniques. The test results demonstrate that the hydrophobicity of coal pyrite is related to the surface products formed during oxidation in aqueous solutions. During oxidation, a sulfur-rich surface layer is produced in near neutral pH solutions. This surface layer is composed mainly of sulfur species in the form of an iron-polysulfide along with a smaller amount of iron oxide/hydroxides. The floatability coal pyrite increases dramatically in the presence of frothers and hydrocarbon collectors. These reagents are believed to absorb on the weakly hydrophobic pyrite surfaces as a result of hydrophobic interaction forces. In Part III, Developing the Best Possible Rejection Schemes, a number of pyrite depressants were evaluated in column and conventional flotation tests. These included manganese (Mn) metal, chelating agents quinone and diethylenetriamine (DETA), and several commercially-available organic depressants. Of these, the additives which serve as reducing agents were found to be most effective. Reducing agents were used to prevent pyrite oxidation and/or remove oxidation products present on previously oxidized surfaces. These data show that Mn is a significantly stronger depressant for pyrite than quinone or DETA. Important factors in determining the pyrite depression effect of Mn include the slurry solid content during conditioning, the addition of acid (HCl), and the amount of Mn. The acid helps remove the oxide layer from the surface of Mn and promotes the depression of pyrite by Mn.

  9. The economics of coal


    Global aspects of the production, consumption and trade in coal are described. World reserves and resources, production (both by region and country), international trade (exporters and importers), coal consumption (by region and sector), and the demand for primary energy (1960-1979). Each of the producing and consuming countries are discussed individually. The electricity sector and its future demand for coal, and the future demand for coking coal are covered. Prices for metallurgical and steam coal are also given. Statistics are presented in tables.

  10. Radionuclides in US coals

    Bisselle, C. A.; Brown, R. D.


    The current state of knowledge with respect to radionuclide concentrations in US coals is discussed. Emphasis is placed on the levels of uranium in coal (and lignite) which are considered to represent a concern resulting from coal combustion; areas of the US where such levels have been found; and possible origins of high radionuclide levels in coal. The report reviews relevant studies and presents new data derived from a computerized search of radionuclide content in about 4000 coal samples collected throughout the coterminous US. 103 references, 5 figures, 5 tables.

  11. Study of distribution of electromagnetic radiation of coal or rock before drivage face

    Li, Z.; Wang, En.; He, X.; Liu, Z.; Jin, S.; Jia, H. [China University of Mining and Technology, Xuzhou (China). School of Mining and Safety Engineering


    In order to study the electromagnetic radiation (EMR) signals at different depths in coal mine driving, working faces were experimentally tested with KBD5 EMR monitoring equipment. Based on the coupling rule of stress and electricity, the relativity of deformation and fracture process of coal or rock and intensity of EMR was analyzed theoretically. The results show that there is a good relation between EMR and the coal stress state, and there are various stress states and deformation and fracture states in coal seams of working faces. There are 4 typical EMR distribution types: that of coal seam exposed for a long time that of coal seam after taking coal and gas outburst prevention measures, that of coal seam newly exposed, and that of coal seam having structure. 14 refs., 7 figs.

  12. An evaluation of deeply-cleaned coals as industrial boiler fuels

    Miller, B.G.; Wincek, R.T.; Scaroni, A.W.


    AMAX Research and Development Center (AMAX) recently conducted a program for the US Department of Energy (DOE) in which processes for preparing ultra-clean coal were developed (Jha et al., 1997). The coal cleaning methods targeted were advanced column flotation and selective agglomeration. The goal was to develop a coal-based fuel, preferably a coal-water slurry fuel (CWSF), that would be a viable alternative to fuel oil or natural gas in industrial and utility boilers, and would also be appropriate for advanced combustion systems that are under development. Additional objectives were to develop near-term applications of the advanced coal cleaning technologies in new or existing coal preparation plants in order to efficiently process minus 28 mesh fines and convert them into marketable products, and to determine the extent of removal of toxic trace elements from coal by the advanced cleaning technologies. AMAX cleaned three coals in an integrated advanced column flotation and selective agglomeration process development unit. The coals were from the Taggart (Virginia), Indiana VII (Indiana) and Hiawatha (Utah) seams. As a complement to the AMAX program, Penn State is evaluating the deeply-cleaned coals as industrial boiler fuels. Specifically, the handling characteristics, combustion performance, and trace element emissions of the coals are being determined. The coals are being tested in demonstration (20 million Btu/h) and research (2 million Btu/h) boilers as part of a Penn State/DOE project characterizing trace element emissions from coal-fired industrial boilers. This paper will discuss the atomization characteristics and combustion performance (in the demonstration boiler) in a 1 ton/h filter cake re-entrainment circuit. In addition, the combustion performance of the ultra-clean CWSFs is compared to that of other CWSFs prepared in Penn State's 1 ton/h single and double-stage grinding circuit.

  13. Coal; Le charbon

    Teissie, J.; Bourgogne, D. de; Bautin, F. [TotalFinaElf, La Defense, 92 - Courbevoie (France)


    Coal world production represents 3.5 billions of tons, plus 900 millions of tons of lignite. 50% of coal is used for power generation, 16% by steel making industry, 5% by cement plants, and 29% for space heating and by other industries like carbo-chemistry. Coal reserves are enormous, about 1000 billions of tons (i.e. 250 years of consumption with the present day rate) but their exploitation will be in competition with less costly and less polluting energy sources. This documents treats of all aspects of coal: origin, composition, calorific value, classification, resources, reserves, production, international trade, sectoral consumption, cost, retail price, safety aspects of coal mining, environmental impacts (solid and gaseous effluents), different technologies of coal-fired power plants and their relative efficiency, alternative solutions for the recovery of coal energy (fuel cells, liquefaction). (J.S.)

  14. The CIS coal summit



    The presentations (overhead/viewgraphs) include: the impacts of EU environmental legislation on Russian coal market (A. Sankovski); how Caterpillar and Cat dealers create value in the global mining industry (D. Mohr); new coal preparation technology and application in the Russian coal market (D. Morris); UK demand outlook and import growth (G. Parker); new technologies in blasting operations and services (J. Petzold and others); a global bank's view of the coal sector (M. Seleznev); ELGA coal deposit, Republic of Sakha (Yakutia), Russia (M. Tsikanov); Russia's economic outlook (P. Forrest); Renaissance Capital (investment bank) (R. Edwards); Russian coal for Korean gencos (S. Kim); and coking coal in Ukraine (V. Khilko).

  15. Rockburst disasters in coal mine

    Manchao HE


    The ruckburst of granite from Kailuan coal mine was reproduced by a new triaxial experimental system. The experimental results show that the rockburst process can be divided into four stages including calm period, grain ejection, sheet cracking and entire collapse. The rockburst intensity is classified by the ratio of maximum principal stress to uniaxial compressive strength. Three types of rockburst for the granite have been defined as delayed rockburst, normal rockburst, and instantaneous rockburst, according to the duration from suddenly unloading to rockburst occurring. Primary mechanism for the granite was studied.

  16. Coal-derived carbon nanotubes by thermal plasma jet

    Tian, Y.; Zhang, Y.L.; Wang, B.J.; Ji, W.J.; Zhang, Y.F.; Xie, K.C. [Nanjing University, Nanjing (China). Dept. of Physics


    A coal/arc-jet technique by directly and successively injecting coal fine particles into the arc plasma jet instead of arcing graphite or coal-based electrodes for producing carbon nanotubes (CNTs) from coal was developed. The derived carbon products by this technique were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), high-resolution TEM (HRTEM), X-ray energy dispersive spectrum (EDS), X-ray diffraction (XRD) and Raman spectrum. The experimental results clearly indicated that certain metal catalysts favored the growth of CNTs in the process, and the relevant growth mechanism was discussed in terms of the characterizations.

  17. Practical design of stepped columns

    Girao Coelho, A.M.; Simao, P.D.; Bijlaard, F.S.K.


    This paper deals with buckling aspects of the design of stepped columns in heavy mill buildings. In these structures, columns have to carry significant axial loads that usually act eccentrically and strength reducing bending moments due to lateral loads. A simple physical model for buckling behaviou

  18. An Undergraduate Column Chromatography Experiment.

    Danot, M.; And Others


    Background information, list of materials needed, and procedures used are provided for an experiment designed to introduce undergraduate students to the theoretical and technical aspects of column chromatography. The experiment can also be shortened to serve as a demonstration of the column chromatography technique. (JN)

  19. On numeric simulation of composite foundation loading capacity of vibro replacement stone column and its experimental analysis%振冲碎石桩复合地基承载力数值仿真与试验分析

    蒋涛; 韦红梅


    According to the loading capacity requirements of the upper structure of some power plant in Xinjiang, the study points out the stone column composite foundation consolidation scheme, points out the comprehensive scheme of the composite foundation loading capacity feature value based on the numeric simulation and field loading experiments, and solves the defects of the common methods for identifying the feature value of the stone column composite foundation loading capacity, so as to provide the reference for similar projects.%针对新疆某电厂上部结构地基承载力要求,提出碎石桩复合地基加固方案,提出基于数值仿真和现场荷载试验综合确定复合地基承载力特征值的综合方案,解决了确定碎石桩复合地基承载力特征值常用方法的弊端,为类似的工程提供依据。

  20. Monitoring the contents of six steroidal and phenolic endocrine disrupting chemicals in chicken, fish and aquaculture pond water samples using pre-column derivatization and dispersive liquid-liquid microextraction with the aid of experimental design methodology.

    Wu, Hongliang; Li, Guoliang; Liu, Shucheng; Hu, Na; Geng, Dandan; Chen, Guang; Sun, Zhiwei; Zhao, Xianen; Xia, Lian; You, Jinmao


    This research established a sensitive and efficient pre-column derivatization HPLC method based on dispersive liquid-liquid microextraction (DLLME) for the simultaneous determination of six steroidal and phenolic endocrine disrupting chemicals (EDCs). In this study, EDCs were firstly labeled by the derivatization reagent 2-(11H-benzo[a]carbazol-11-yl) ethyl carbonochloridate (BCEC-Cl) and then extracted by DLLME. The response surface methodology was employed to investigate the key parameters of pre-column derivatization and DLLME. Under the optimal conditions, a good linear relationship between the peak area and the concentration of analytes was observed with correlation coefficients of >0.9991. Limits of detection for all EDCs derivatives were achieved within the range of 0.02-0.07 μg L(-1). The proposed method has the advantages of simple operation, low consumption of organic solvent, saving time, low output limit and good selectivity. When applied to several food and water samples analysis, it demonstrated good applicability for the determination of EDCs.

  1. 大比尺高含钢率型钢混凝土柱滞回性能试验%Experimental study on hysteretic properties of large-size SRC columns with high ratio of encased steel

    殷小激; 吕西林; 卢文胜


    对8个含钢率分别为13.12%和15.04%的大比尺型钢混凝土柱进行水平低周反复加载试验,考察高含钢率型钢混凝土框架柱在反复荷载作用下的受力特点、破坏形态和变形特征。试件设计轴压比介于0.5~1.2之间,在压、弯、剪共同作用下发生弯曲型破坏。试验得到荷载一位移滞回曲线及型钢和钢筋的应变曲线,验证了型钢与混凝土的共同工作性能。试件滞回曲线具有良好的饱满性,每级滞回环大致重合,承载力没有发生明显退化,表明构件具有良好的耗能性能和抗震能力。根据平衡方程提出的承载力实用计算方法,可以相对准确的预测内置十字形带翼缘型钢的型钢混凝土柱正截面抗弯承载力。得到的截面M-N关系曲线可以为设计和进一步研究提供参考。%8 large-size SRC columns with 13.12% and 15.04% encased steel were tested under low-frequency cyclic lateral loading. The mechanical properties, failure modes and deformabilities are studied. The axial load ratios of the specimens range from 0.5 to 1.2. All the specimens showed flexure failures subject to combined axial force, bending moment and shear forces. Force-displacement hysteretic curves, strain curves of encased steels and rebars are obtained. The interaction behavior between encased steels and concrete are verified. The hysteretic curves of columns are plump in shapes. Hysteresis loops keep coincident under the same levels of lateral loads, and the bearing capacities does not change much, which indicate that the columns have good energy-dissipation performance and aseismic capacity. Based on the equilibrium equation, the suggested practical calculation method can accurately predict the bending-resistant capacities of SRC columns with encased cross-shaped section steels. The obtained M-N curves of cross-sections of SRC columns can be used as references tbr further studies.

  2. 提高异形柱框架节点抗震性能的试验研究%Experimental research on seismic behavior of joints of specially shaped columns

    戎贤; 张健新; 李艳艳


    In efforts to solve the issues of weak part of joints of specially shaped columns, a study testing under low cyclic loading used for the joint of specially shaped columns reinforced by X-shaped reinforcement, polypropylene fiber and steel fiber reinforcement in the core zone of joints, and the joint of specially shaped column without rein?forcement under the same condition was conducted. A comparison was performed for these three kinds of reinforce?ment in such seismic performance indices as the damage characteristic, bearing capacity, displacement ductility, hysteretic curve, rigidity degradation, energy dissipation and cumulated damage. It was revealed that, comparing with the joint of specially shaped column without reinforcement, the seismic behaviors of the joints of specially shaped column reinforced by X-shaped reinforcement, polypropylene fiber or steel fiber were obviously improved. The bearing capacity and deformation capacity of joint reinforced by X-shaped reinforcement, polypropylene fiber or steel fiber in core zone was enhanced, and simultaneously the hysteretic characteristic was improved significantly and the degree of cumulated damage was lightened. Besides, the bearing capacity of a joint reinforced by X-shaped reinforcement in core zone was higher and the degree of cumulated damage was lighter than that reinforced by fiber.%为了解决异形柱结构节点的薄弱问题,对异形柱框架节点核心区应用X形配筋增强、聚丙烯纤维增强及钢纤维增强的异形柱节点与同条件下未增强的异形柱节点进行拟静力试验研究,对比3种方法增强的异形柱框架节点试件的破坏特征、承载能力和位移延性、滞回曲线、刚度退化、耗能能力和累积损伤等抗震性能指标.研究结果表明:与未被增强的异形柱节点相比,X形配筋增强、聚丙烯纤维增强或钢纤维增强的异形柱节点抗震性能显著提高.在异形柱节点核心区加入X形配筋、掺入聚丙

  3. Power coal plasma gasification. Computation and experiment

    N.A. Bastyrev; V.I. Golysh; M.A. Gorokhovski; Yu.E. Karpenko; V.G. Lukiaschenko; V.E. Messerle; A.O. Nagibin; E.F. Osadchaya; S.F. Osadchy; I.G. Stepanov; K.A. Umbetkaliev; A.B. Ustimenko [Combustion Problems Institute, Almaty (Kazakhstan)


    Results of complex experimental and numerical investigation of coal plasma gasification in steam and air are presented. To analyse numerically the universal thermodynamic calculation code TERRA was used. The data base of it contains thermodynamic properties for 3500 individual components in temperature interval from 300 to 6000 K. Experiments were fulfilled at an original installation for coal plasma gasification. Nominal power of the plasma gasifier is 100 kW and sum consumption of the reagents is up to 25 kg/h. High integral indexes of the gasification processes were achieved. The numerical and experimental results comparison showed their satisfied agreement. 7 refs., 7 figs., 3 tabs.

  4. Mathematical Modelling of Coal Gasification Processes

    Sundararajan, T.; Raghavan, V.; Ajilkumar, A.; Vijay Kumar, K.


    experimental and modelling work has been undertaken to investigate the gasification characteristics of high ash Indian coals and compare the yield with those of high grade Australian and Japanese coals. A 20 kW capacity entrained flow gasifier has been constructed and the gasification characteristics have been studied for Indian coals for different particle sizes, system pressures and air flow rates. The theoretical model incorporates the effects of Knudsen diffusion, devolatilization and various heterogenous and homogenous kinetic steps as well as two-phase flow interactions involving the gaseous and particle phases. Output parameters such as carbon conversion, cold gas efficiency and syngas composition have been compared for different grades of coals under a wide range of operating conditions. The model developed for the entrained flow gasifier predicts the gasification characteristics of both Indian and foreign coals well. Apart from the entrained flow gasifier, a bubbling bed gasifier of 100 kW capacity has also been studied. A pilot plant for the gasification of Indian coals has been set up for this capacity and its performance has been investigated experimentally as well as theoretically at different air and steam flow rates. Carbon conversion efficiency of more than 80% has been achieved.

  5. 软煤体孔隙结构影响瓦斯吸附特性的试验研究%Experimental study on the effect of pore structure of soft coal body on gas absorption characteristics

    许满贵; 孟然; 韩金子; 方秦月; 张宏亮


    为了掌握软煤体孔隙结构对瓦斯吸附特性的影响作用,基于分形几何理论,采用低温氮吸附和恒温吸附试验方法,对软煤体孔隙结构特征及其对瓦斯吸附特性的影响进行研究,并与硬煤相关特性进行对比分析.研究结果表明:软煤初始氮吸附量大于硬煤,软煤呈现的吸附滞后环比硬煤更为明显,且吸附曲线在高相对压力段上升速率更快,软煤比表面积和孔容均大于硬煤,孔隙数量远大于硬煤,尤其是微孔内吸附力场的叠加作用和中孔内的扩散作用使得软煤吸附势能增强,引入吸附停留时间概念,得出软煤表面较多的吸附位使得瓦斯在软煤体表面吸附停留时间更长,软煤表面分形特征更为明显,软煤表面分维数平均是硬煤的1.47倍,软煤的饱和吸附量及达到饱和吸附的速率均大于硬煤.%In order to grasp the effect of pore structure of soft coal body on gas adsorption characteristics,based on the fractal geometry theory,the characteristics of pore structure of the soft coal body and the its influence of gas adsorption characteristics were studied and the hard coal related features compared with soft coal were analyzed by the low temperature liquid nitrogen ad-sorption and adsorption isotherms experiment. The research results show that in the initial stage nitrogen adsorption quantity of soft coal is greater than the hard coal,the adsorption hysteresis ring presented by soft coal is more apparent than hard coal and rise rate of adsorption curve in high relative pressure section is more faster;the specific surface area and pore volume of soft coal are greater than hard coal,the pore quantity is far more greater than hard coal,especially,the superposition of adsorption force field of micropore and diffusion of middle hole makes the en-hancement of soft coal adsorption potential energy;the adsorption residence time of coal to gas of soft coal is more longer

  6. Moving Bed Gasification of Low Rank Alaska Coal

    Mandar Kulkarni


    Full Text Available This paper presents process simulation of moving bed gasifier using low rank, subbituminous Usibelli coal from Alaska. All the processes occurring in a moving bed gasifier, drying, devolatilization, gasification, and combustion, are included in this model. The model, developed in Aspen Plus, is used to predict the effect of various operating parameters including pressure, oxygen to coal, and steam to coal ratio on the product gas composition. The results obtained from the simulation were compared with experimental data in the literature. The predicted composition of the product gas was in general agreement with the established results. Carbon conversion increased with increasing oxygen-coal ratio and decreased with increasing steam-coal ratio. Steam to coal ratio and oxygen to coal ratios impacted produced syngas composition, while pressure did not have a large impact on the product syngas composition. A nonslagging moving bed gasifier would have to be limited to an oxygen-coal ratio of 0.26 to operate below the ash softening temperature. Slagging moving bed gasifiers, not limited by operating temperature, could achieve carbon conversion efficiency of 99.5% at oxygen-coal ratio of 0.33. The model is useful for predicting performance of the Usibelli coal in a moving bed gasifier using different operating parameters.

  7. Comprehensive Fractal Description of Porosity of Coal of Different Ranks

    Jiangang Ren


    Full Text Available We selected, as the objects of our research, lignite from the Beizao Mine, gas coal from the Caiyuan Mine, coking coal from the Xiqu Mine, and anthracite from the Guhanshan Mine. We used the mercury intrusion method and the low-temperature liquid nitrogen adsorption method to analyze the structure and shape of the coal pores and calculated the fractal dimensions of different aperture segments in the coal. The experimental results show that the fractal dimension of the aperture segment of lignite, gas coal, and coking coal with an aperture of greater than or equal to 10 nm, as well as the fractal dimension of the aperture segment of anthracite with an aperture of greater than or equal to 100 nm, can be calculated using the mercury intrusion method; the fractal dimension of the coal pore, with an aperture range between 2.03 nm and 361.14 nm, can be calculated using the liquid nitrogen adsorption method, of which the fractal dimensions bounded by apertures of 10 nm and 100 nm are different. Based on these findings, we defined and calculated the comprehensive fractal dimensions of the coal pores and achieved the unity of fractal dimensions for full apertures of coal pores, thereby facilitating, overall characterization for the heterogeneity of the coal pore structure.

  8. Comprehensive fractal description of porosity of coal of different ranks.

    Ren, Jiangang; Zhang, Guocheng; Song, Zhimin; Liu, Gaofeng; Li, Bing


    We selected, as the objects of our research, lignite from the Beizao Mine, gas coal from the Caiyuan Mine, coking coal from the Xiqu Mine, and anthracite from the Guhanshan Mine. We used the mercury intrusion method and the low-temperature liquid nitrogen adsorption method to analyze the structure and shape of the coal pores and calculated the fractal dimensions of different aperture segments in the coal. The experimental results show that the fractal dimension of the aperture segment of lignite, gas coal, and coking coal with an aperture of greater than or equal to 10 nm, as well as the fractal dimension of the aperture segment of anthracite with an aperture of greater than or equal to 100 nm, can be calculated using the mercury intrusion method; the fractal dimension of the coal pore, with an aperture range between 2.03 nm and 361.14 nm, can be calculated using the liquid nitrogen adsorption method, of which the fractal dimensions bounded by apertures of 10 nm and 100 nm are different. Based on these findings, we defined and calculated the comprehensive fractal dimensions of the coal pores and achieved the unity of fractal dimensions for full apertures of coal pores, thereby facilitating, overall characterization for the heterogeneity of the coal pore structure.

  9. Release of inorganic material during coal devolatilization. Milestone report

    Baxter, L.L.


    Experimental results presented in this paper indicate that coal devolatilization products convectively remove a fraction of the nonvolatile components of inorganic material atomically dispersed in the coal matrix. Results from three facilities burning six different coals illustrate this mechanism of ash transformation and release from coal particles. Titanium is chosen to illustrate this type of mass release from coal particles on the basis of its low volatility and mode of occurrence in the coal. During moderate rates of devolatilization (10{sup 4} K/s heating rate), no significant loss of titanium is noted. At more rapid rates of heating/devolatilization (10{sup 5} K/s) a consistent but minor (3-4 %) loss of titanium is noted. During rapid devolatilization (5xl0{sup 5} K/s and higher), significant (10-20 %) amounts of titanium leave the coal. The loss of titanium monitored in coals ranging in rank from subbituminous to high-volatile bituminous coals and under conditions typical of pulverized-coal combustion. The amount of titanium lost during devolatilization exhibits a complex rank dependence. These results imply that other atomically dispersed material (alkali and alkaline earth elements) may undergo similar mechanisms of transformation and release.


    Lee, S.


    The objective of the present work is to model the resin particles within the column during fluidization and sedimentation processes using computation fluid dynamics (CFD) approach. The calculated results will help interpret experimental results, and they will assist in providing guidance on specific details of testing design and establishing a basic understanding of particle’s hydraulic characteristics within the column. The model is benchmarked against the literature data and the test data (2003) conducted at Savannah River Site (SRS). The paper presents the benchmarking results and the modeling predictions of the SRS resin column using the improved literature correlations applicable for liquid-solid granular flow.

  11. Transient flow and heating characteristics in a pinched plasma column.

    York, T. M.; Stover, E. K.


    The generation of axial flow and heating of an argon plasma in a pinched plasma column of a pulsed, linear z-pinch device was examined experimentally and analytically. Transient (about 5 microsec) axial pressure profiles identify three characteristic periods in the column history. These include (1) strong axial pressure asymmetry indicative of plasma streaming, (2) isotropic, rapidly rising plasma pressure indicative of plasma heating, and (3) column breakup. An efficient conversion of radial collapse to axial streaming velocity is identified. Mechanisms for such an effect and subsequent heating are evaluated; significance to transients in pulsed plasma accelerators is identified.

  12. Mush Column Magma Chambers

    Marsh, B. D.


    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  13. Laboratory studies of briquetting and coking of hard brown coals

    Wollenberg, R.; Basanshaw, B.


    Assesses feasibility of producing lumpy, high strength coke from hard brown coal unsuitable for conventional briquetting and coking technologies. Laboratory studies used brown coal with 11.5 to 23.5% ash content and 11.8 to 48% coal moisture from the Adun-tschulun, Scharin-gol, Baga-nur and Nalaich deposits in Mongolia. Two experimental briquetting technologies (briquetting of pregranulated coal dust, briquetting of dried coal from slurry comminution) were applied. Resulting briquets were coked at maximum 1,000 C temperature. Graphs provide briquetting and coking results. Influence of major briquetting and coking parameters is evaluated. The highest briquet compression strength obtained ranged between 15.2 and 34.3 MPa, the highest coke compression strength was 32.0 up to 87.0 MPa. Studies proved that suitable coke for use in the metallurgical and chemical industry can be produced from various types of hard brown coal. 6 refs.

  14. Pressure drop in CIM disk monolithic columns.

    Mihelic, Igor; Nemec, Damjan; Podgornik, Ales; Koloini, Tine


    Pressure drop analysis in commercial CIM disk monolithic columns is presented. Experimental measurements of pressure drop are compared to hydrodynamic models usually employed for prediction of pressure drop in packed beds, e.g. free surface model and capillary model applying hydraulic radius concept. However, the comparison between pressure drop in monolith and adequate packed bed give unexpected results. Pressure drop in a CIM disk monolithic column is approximately 50% lower than in an adequate packed bed of spheres having the same hydraulic radius as CIM disk monolith; meaning they both have the same porosity and the same specific surface area. This phenomenon seems to be a consequence of the monolithic porous structure which is quite different in terms of the pore size distribution and parallel pore nonuniformity compared to the one in conventional packed beds. The number of self-similar levels for the CIM monoliths was estimated to be between 1.03 and 2.75.

  15. The release of iron during coal combustion. Milestone report

    Baxter, L.L. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility


    Iron plays an important role in the formation of both fly ash and deposits in many pulverized-coal-fired boilers. Several authors indicate that iron content is a significant indicator of the slagging propensity of a majority of US bituminous coals, in particular eastern bituminous coals. The pyritic iron content of these coals is shown to be a particularly relevant consideration. A series of investigations of iron release during combustion is reported for a suite of coals ranging in rank from lignite to low-volatile bituminous coal under combustion conditions ranging from oxidizing to inert. Experimental measurements are described in which, under selected conditions, major fractions of the iron in the coal are released within a 25 ms period immediately following coal devolatilization. Mechanistic interpretation of the data suggest that the iron is released as a consequence of oxygen attack on porous pyrrhotite particles. Experimental testing of the proposed mechanism reveals that the release is dependent on the presence of both pyrite in the raw coal and oxygen in the gas phase, that slow preoxidation (weathering) of the pyrite significantly inhibits the iron release, and that iron loss increases as oxygen penetration of the particle increases. Each observation is consistent with the postulated mechanism.

  16. Class 4 stainless steel box columns in fire

    Uppfeldt, Björn; Veljkovic, Milan, ed. lit.


    A study of stainless steel cold-rolled box columns at elevated temperatures is presented, which is a part of an on-going RFCS project "Stainless Steel in Fire". Experimental results of six, class 4, stub columns at elevated temperature, tested by Ala-Outinen (2005), were used to evaluate the FE model. The FE analysis obtained using the commercially available software, ABAQUS, shows that the critical temperature was closely predicted. Further, a parametric study was performed using the same nu...


    Heung, L.; Sessions, H.; Xiao, S.


    The Thermal Cycling Absorption Process (TCAP) was further studied with a new configuration. Previous configuration used a palladium packed column and a plug flow reverser (PFR). This new configuration uses an inverse column to replace the PFR. The goal was to further improve performance. Both configurations were experimentally tested. The results showed that the new configuration increased the throughput by a factor of more than 2.

  18. A Technique for Decreasing Reactivity of Coal Material to Suppress the Oxygen Absorption Process

    Timofeeva, S. S.; Lugovtsova, N. Yu; Gubanova, A. R.


    The paper describes the mechanisms of self-ignition formation in coal liable to spontaneous combustion, on the basis of experimental works performed to analyze heat and mass transfer in the coal-air system. A new approach was developed to the coal self-heating suppression and thermodynamic control of the oxidation process. The influence of coal moisture content and thermal behaviour of air in the cooling process was studied during moisture evaporation.

  19. Development of Regression Models for Assessing Fire Risk of Some Indian Coals

    Devidas S. Nimaje; D.P. Tripathy; Santosh Kumar Nanda


    Spontaneous combustion of coals leading to mine fires is a major problem in Indian coal mines that creates serious safety and mining risk. A number of experimental techniques based on petrological, thermal and oxygen avidity studies have been used for assessing the spontaneous heating liability of coals all over the world. Crossing point temperature (CPT) is one of the most common methods in India to assess the fire risk of coal so that appropriate strategies and effective action plans could...

  20. Preliminary experimental study of bituminous coal gasification on dual fluidized beds%烟煤在双流化床中气化特性初步实验研究

    武小军; 范晓旭; 陈文义; 初雷哲


    利用一套高3m的双流化床煤气化实验系统,以烟煤为燃料进行了气化初步实验研究.烟煤在气化炉中进行热解气化,生成的半焦经下返料器送入燃烧炉进行燃烧,通过高温循环灰携带能量供给气化炉.通过调整气化炉内料层高度改变燃料在气化炉内的停留时间,从而影响气化效果,料层高度可以通过气化炉内压差进行监测.烟煤气化达到稳定工况时,燃烧炉和气化炉的温度和压差基本保持稳定.燃气热值为5.53 MJ/m3,尚未达到中热值标准,原因在于实验装置规模较小导致散热损失较大,同时返料器以空气为返料风降低了燃气品质.%Gasification experiments on bituminous coal were made in an experimental system of dual fluidized beds with 3 m in height. Gasifier was used for coal pyrolysis/gasification. Semicarbon was sent into burner for combustion by U-valve. Energy for gasification was carried by high temperature cycle ash. Status of gasification can be influenced by residence time of fuel which can be changed by adjusting the bed material level in gasifier. Differential pressures in gasifier were used for analyzed the bed material level. The temperature and differential pressure in gasifier and burner maintained stability when gasification condition operated steadily. The calorific value of gas was 5.53 MJ/Nm3 and didn't reach the standard of medium heat value. The cause is that the heat loss is bigger in small size and gas quality was decreased by the air which is used as return wind.