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By means of the raw material grading the porous permeable material was prepared with the electrofused corundum with the porcelain PFL-1 bond. The samples with improved properties were obtained when introducing in the mass of 5 weigh percent of porcelain bond (above 100 % of the fller) after the burning at 1450 оC. Their ultimate strength at bending was 14,6 MPa, the open porosity was 44 % and the gas permeability factor was 0,85 micron2. Ref. 10. Tab. 3.

Porous permeable materials are prepared by selecting the grain size composition with electromelted corundum filler and porcelain mix PFL-1 binder. Specimens with an improved set of properties are prepared with addition to the composition of 5 wt.% porcelain binder (above 100% filler) after firing at 1450°C. Specimen ultimate strength in bending is 14.6 MPa, open porosity 44%, and gas permeability coefficient 0.85 μm2.

Porous permeable materials of electromelted corundum with fineness of 2 – 3 and 0.5 mm are prepared with a porcelain mix binder. Ratios in filler fractions 2 – 3 and 0.5 mm: 0/95, 35/60, 40/55, 45/50, 50/45, and 95/0. Specimens are compacted under a pressure of 24, 50, and 100 MPa and fired at 1350 and 1450°C. Sintered specimen ultimate strength in bending is from 1.9 to 15.3 MPa, open porosity 17 and 26%, gas permeability coefficient of single-fraction compositions from 1.19 to 3.27 μm2. The porous permeable ceramic material obtained is promising for use in the form of filters and ceramic membrane substrates.

Strong porous permeable ceramic is studied, prepared by selection of grain size compositions with filler of electromelted corundum grades F600 (100 – 200 μm), F360 (40 – 60 μm), and F120 (10 – 20 μm). The strengthening binders used are very fine corundum powder (~2 μm), alloyed with 0.25 wt.% MgO; a mixture of SiC (particle size 3 – 4 μm) and MgO (particle size 1 – 2 μm) in a ratio of 2:1. Specimens in the form of bars 60 × 15 × 5.5 mm are prepared by uniaxial semidry compaction under a pressure of 50 MPa (for single fraction compositions) and 25 MPa (for three-fraction compositions). Specimens are fired in air at temperatures from 1350 to 1550°C. Specimen open porosity varies from 28 to 43%, and ultimate strength in bending from 1 to 36 MPa. The best strength is obtained using a binder in the system SiC–MgO (5 wt.% binder above 100% of filler, σben = 36 MPa, and open porosity is 30%).

Porous permeable ceramic is prepared from electromelted corundum (EMC) with fineness of about 0.5 mm with added porcelain. Compositions are prepared with different ratios of EMC/porcelain: 99/1, 97/3, 95/5, 93/7, and 90/10. Specimens in the form of bars with a size of 40 × 7 × 6.5 mm are prepared by uniaxial semidry compaction under a pressure of 25 and 50 MPa and fired at 1350 and 1450°C. Specimen open porosity varies from 22 to 30%, and ultimate strength in bending from 1.1 to 9.3 MPa. Porous ceramic is promising for filters and ceramic membrane substrates.

The strengthened porous ceramics was investigated in the article which had been obtained by the grain composition mix design using the electro-fused corundum aggregates: F600 (particle size is 100‒200 micron); F360 (40‒60 micron) and F120 (10‒20 micron). In the capacity of strengthening binders the highly dispersed corundum powders (about 2 micron) doped with 0,25 wt. % of MgO; and the mixture of SiC powder (3‒4 micron) and of MgO powder (1‒2 micron) in the ratio of 1:2 were used. The test-beams of the size 60×15×5,5 mm were obtained by means of uniaxial semi-dry compacting under the pressure of 50 MPa (for mono-fractional compositions) and of 25 MPa (for three-fractional compositions). The samples were burnt on the air at the temperatures from 1350 to 1550 °C. The open porosity varied from 28 to 43 %, the ultimate bending strength varied from 1 to 36 MPa. The highest strength was attained when the SiC‒MgO binder was used (5 wt. % of the binder over 100 % of the aggregate, the ultimate bending strength was 36 MPa, the open porosity was 30 %). Ref. 12. Tab. 5.

A study is made of a strong porous ceramic based on granular mixes of a filler—electrofused corundum with particle sizes of 2 – 3 and 0.5 mm (95 wt.% of the mix) — and a porcelain binder (5 wt.%). Several mixes were prepared with different values for the 2 – 3 mm/0.5 mm ratio of filler-particle sizes: 0/95, 35/60, 40/55, 45/50, 50/45, and 95/0. The specimens were pressed at pressures of 25, 50 and 100 MPa and fired at temperatures of 1350 and 1450°C. The sintered specimens ranged from 19 to 143 MPa in ultimate flexural strength and 17 to 26% in open porosity. The results are attributed to the formation of a framework in the semifinished product along with regions outside the framework. The new porous permeable ceramic is promising for use in the form of filters and supports for ceramic membranes.

The Lyhamyar deposit is a large Sb deposit in the Southern Shan Plateau, Eastern Myanmar. The deposit is located in the Early Silurian Linwe Formation, occurring as syntectonic quartz-stibnite veins. The ore body forms an irregular staircase shape, probably related to steep faulting. Based on the mineral assemblages and cross-cutting relationships, the deposit shows two mineralization stages: (1) the pre-ore sedimentary and diagenetic stage, and (2) the main-ore hydrothermal ore-forming stage (including stages I, II, and III), i.e., (i) early-ore stage (stage I) Quartz-Stibnite, (ii) late-ore stage (stage II) Quartz-calcite-Stibnite &plusmn, Pyrite, and (iii) post-ore stage (stage III) carbonate. The ore-forming fluid homogenization temperatures from the study of primary fluid inclusions in quartz and calcite indicate that the ore-forming fluid was of a low temperature (143.8&ndash, 260.4 &deg, C) and moderate to high-salinity (2.9&ndash, 20.9 wt. % NaCl equivalent). Hydrogen and oxygen isotopes suggest that the ore-forming fluids of the Lyhamyar deposit were derived from circulating meteoric water mixed with magmatic fluids that underwent isotopic exchange with the surrounding rocks. Sulfur in Lyhamyar was dominated by thermochemical sulfate reduction (TSR) with dominant magmatic source sulfur. The lead isotope compositions of the stibnite indicate that the lead from the ore-forming metals was from the upper crustal lead reservoir and orogenic lead reservoir. On the basis of the integrated geological setting, ore geology, fluid inclusions, (H-O-S-Pb) isotope data, and previous literature, we propose a new ore-deposit model for the Lyhamyar Sb deposit: It was involved in an early deposition of pyrite in sedimentary and diagenetic stages and later Sb mineralization by mixing of circulating meteoric water with ascending magmatic fluids during the hydrothermal mineralization stage.

The Gulf of Thailand is characterized by shallow-water depth wells with bottomhole static temperature ranging from 240 to more than 420°F. These wells are drilled to an average of 12,000 ft MD and 9,000 ft TVD with a fast paced-batch drilling strategy. Most cement jobs are done offline, and on the surface section can be as frequent as 6 jobs per day. With multiple rigs, operators can require more than 100 cementing operations per month and cement volumes as high as 18,000 bbl. This efficient operations environment creates a demand for a logistically and operationally simple cement system that can be applied in all well sections and across the full range of expected temperatures. An advanced, lightweight seawater-based cementing concept was tested for this application. This new cementing system uses a single blend with only 3 to 4 primary liquid additives (including a stable, high-temperature, multi-functional polymer) to adjust all primary cement jobs for the entire wellbore. A sophisticated lab testing program was conducted for the innovative cementing concept according to the required demands on cement slurry design given the harsh wellbore conditions in the Gulf of Thailand. Tests revealed that the developed cementing systems meet all well requirements despite low densities of 13.3 to 14.0 ppg with high water content. This advanced cementing system was introduced in 2011 and has gradually been used on all wells since then – to date more than 500 wells in the Gulf of Thailand. In addition to improving logistics, use of the system has enhanced cement bond quality in production tubing cementing jobs. This improvement also reduced pay at risk due to insufficient cement isolation. This is evident in the whole range of well temperatures.

The Gulf of Thailand is characterized by shallow-water depth wells with bottomhole static temperature ranging from 240 to more than 420°F. These wells are drilled to an average of 12,000 ft MD and 9,000 ft TVD with a fast paced-batch drilling strategy. Most cement jobs are done offline, and on the surface section can be as frequent as 6 jobs per day. With multiple rigs, operators can require more than 100 cementing operations per month and cement volumes as high as 18,000 bbl. This efficient operations environment creates a demand for a logistically and operationally simple cement system that can be applied in all well sections and across the full range of expected temperatures. An advanced, lightweight seawater-based cementing concept was tested for this application. This new cementing system uses a single blend with only 3 to 4 primary liquid additives (including a stable, high-temperature, multi-functional polymer) to adjust all primary cement jobs for the entire wellbore. A sophisticated lab testing program was conducted for the innovative cementing concept according to the required demands on cement slurry design given the harsh wellbore conditions in the Gulf of Thailand. Tests revealed that the developed cementing systems meet all well requirements despite low densities of 13.3 to 14.0 ppg with high water content. This advanced cementing system was introduced in 2011 and has gradually been used on all wells since then – to date more than 500 wells in the Gulf of Thailand. In addition to improving logistics, use of the system has enhanced cement bond quality in production tubing cementing jobs. This improvement also reduced pay at risk due to insufficient cement isolation. This is evident in the whole range of well temperatures.