Risk monitoring and early-warning technology of coal mine production

This article was written according to the secudty information theory and the secudty cybernetics basic principle, for reducing the accident risk effectively and safeguarding the production safety in coal mine. First, each kind of risk characteristic has carried on the earnest analysis to the coal-mining production process. Then it proposed entire wrap technology system of the risk management and the risk monitoring early warning in the coal-mining production process, and developed the application software-coal mine risk monitoring and the early warning system which runs on the local area network. The coal-mining production risk monitoring and early warning technology system includes risk information gathering, risk identification and management, risk information transmission; saving and analysis, early warning prompt of accident risk, safety dynamic monitoring, and safety control countermeasure and so on. The article specifies implementation method and step of this technology system, and introduces application situations in cooperating mine enterprise, e.g. Xiezhuang coal mine. It may supply the risk management and the accident prevention work of each kind of mine reference.

Application of coal mine dynamic safety management and occupational health and safety management system

A method system was put forward based on the occupational health and safety management system to develop the dynamic safety management of coal mine. It aimed at the problems in the mining safety management and was put in practice in Lingxin coal mine of Ningxia Coal Industry Group Co., Ltd.. And good effect was obtained in safety work. It developed the mining dynamic safety management based on the building of occupational health and safety management system of mining enterprise and its main contents are as follows： timely identification and dynamic control of accident risk, persistent improvement of safety management performance according to the ＂PDCA＂ circle.

ZSM-5/MAPO Composite Catalyst for Converting Methanol to Olefins in a Two-Stage Unit with a Dimethyl Ether Pre-Reactor

A ZSM-5/MAPO composite catalyst was prepared by adding ZSM-5 zeolite powder to a conventional molecular sieve synthesis system, followed by modification with NH_4H_2PO_4. The samples were characterized by XRD, SEM, IR, NH_3-TPD, and BET analyses. The catalytic property of the samples toward the methanol-to-olefin(MTO) reaction was evaluated in a connected in series two-stage unit equipped with a continuous flow(once-through) fixed-bed tubular reactor similar to an industrial reactor. The first reactor mainly converted methanol into dimethyl ether and water, followed by being subject to continuous reaction in the second reactor, in which DME was converted to hydrocarbons. The composites exhibited the typical framework topology of MFI, AEI and AFI, which represented the ZSM-5 zeolite, the molecular sieves AlPO-18 or SAPO-18, AlPO-5 or SAPO-5, respectively. The composites showed several advantages for optimizing the zeolite acidity, enhancing the mass transfer, and restraining the side reactions. Catalytic reaction results showed that the composites exhibited higher selectivity to light olefins(84.0%) and lower selectivity to C_2―C_4 alkanes and C_5^+ hydrocarbons than pure ZSM-5. Moreover, the composite zeolite loaded with 3% of P demonstrated improved catalytic activity and stability for the conversion of methanol to propylene, because the coking rate was obviously suppressed.

Reaction mechanism and kinetics of pressurized pyrolysis of Chinese oil shale in the presence of water

A study of reaction mechanisms and chemical kinetics of pressurized pyrolysis of Chinese Liushuhe oil shale in the presence of water were conducted using an autoclave for simulating and modeling in-situ underground thermal degradation.It was found that the oil shale was first pyrolyzed to form pyrobitumen,shale oil,shale gas and residue,then the pyrobitumen was further pyrolyzed to form more shale oil,shale gas,and residue.It means that there are two consecutive and parallel reactions.With increasing temperature,the pyrobitumen yield,as intermediate,first reached a maximum,then decreased to approximately zero.The kinetics results show that both these reactions are first order.The activation energy of pyrobitumen formation from oil shale is lower than that of shale oil formation from pyrobitumen.

Performance test of a 5 kW solid oxide fuel cell system under high fuel utilization with industrial fuel gas feeding

As the demand for green energy with high efficiency and low carbon dioxide(CO2)emissions has increased,solid oxide fuel cells(SOFCs)have been intensively developed in recent years.Integrated gasification fuel cells(IGFCs)in particular show potential for large-scale power generation to further increase system efficiency.Thus,for commercial application of IGFCs,it is important to design reliable multi-stacks for large systems that show long-term stability and practical fuel gas for application to industrial equipment.In this work,a test rig(of a 5 kW SOFC system,with syngas from industrial gasifiers as fuel)was fabricated and subjected to long-term tests under high fuel utilization to investigate its performance.The maximum steady output power of the system was 5700 W using hydrogen and 5660 W using syngas and the maximum steady electrical efficiency was 61.24%while the fuel utilization efficiency was 89.25%.The test lasted for more than 500 h as the fuel utilization efficiency was larger than 83%.The performances of each stack tower were almost identical at both the initial stage and after long-term operation.After 500 h operation,the performances of the stack towers decreased only slightly under lower current and showed almost no change under high current.These results demonstrate the reliability of the multi-stack design and the prospect of this SOFC power-generation system for further enlarging its application in a MWth demonstration.

Thermodynamics fundamentals and energy efciency for the separation and high‑valued utilization of Fischer–Tropsch heavy oil

The development trend of Fischer–Tropsch(F–T)technology is to develop high value-added products.The separation of linearα-olefns with low cost is an efective method.Nevertheless,the lack of thermodynamic data and the huge energy consumption are the two main problems restricting the development of the separation process.The thermodynamic data of the key components(1-dodecene and n-dodecane)in the F–T product were measured.The Wilson binary interaction parameters of the key components were obtained.Next,one traditional distillation column sequence and two dividing wall column(DWC)sequences were designed to separate the F–T heavy oil to obtain narrow fractions with diferent carbon numbers.Then,the obtained fractions of C10 and C12 were simulated to obtain 1-decene and 1-dodecene,respectively.There was a traditional distillation and a diferential pressure thermal coupling distillation process.When separating 95.0%purity 1-decene and 1-octene,the direct DWC process and diferential pressure thermal coupled distillation are an excellent combination,which can reduce the energy by 33.1%(i.e.,11,286 kW)and total annual cost by 15.9%(i.e.,3.96×10^(6)$)compared with traditional distillation.

Fast and low-temperature elimination of organic templates from SBA-15 using dielectric barrier discharge plasma

Organic templates P-123 of mesoporous SBA-15 can be effectively removed in a few minutes （4 min） by using the dielectric-barrier discharge （DBD） plasma technique at ambient pressure and low gas temperature （around 130℃）. The mesoporous SBA-15 was characterized by FT-IR, 29Si solid sate NMR, TEM, XRD, TGA and N2 adsorption/desorption isotherms. The as-made SBA-15 treated with DBD plasma exhibited a larger surface area of 790 m2 · g-1 with larger pores and microspore volume than samples prepared by using the conventional thermal calcination method （550 ℃ and 5 h, 660 m2 · g-1）. In addition to less shrinkage of the silica framework, the DBD-prepared SBA-15 showed significantly increased weight loss of 8.3% about 200℃ as compared with that of conventional calcination （5.5%）, which is attributed mainly to the dehydroxylation by condensation of silanol groups.

Synthesis of PP-g-PIP and Properties of PP/PP-g-PIP Binary Blends

The polypropylene-grafl-polyisoprene （PP-g-PIP） copolymers with different side chain length were synthesized by the combination of solid phase graft and anionic polymerization. The copolymers were characterized by nuclear magnetic resonance spectrum （1H-NMR）, gel permeation chromatography （GPC） and differential scanning calorimetry （DSC）. Five PP/PP-g-PIP blends with PP-g-PIP as a flexibilizer to toughen PP were prepared and characterized by scanning electron microscope （SEM）, dynamic mechanical analysis （DMA）, DSC, wide-angle X-ray diffraction （WAXD）. Their morphologies, glass transition temperatures, crystallinity and mechanical properties were investigated. All the results pointed out that the covalent bonding of PP and PIP increased the compatibility and interfacial adhesion, which led to PIP well dispersed in the system and small size PIP particles in the binary blends. In addition, the toughness of PP was improved while its tensile strength slightly decreased.

HYDROGEN-BONDING INDUCED CHANGE OF CRYSTALLIZATION BEHAVIOR OF POLY(BUTYLENE SUCCINATE) IN ITS MIXTURES WITH BISPHENOL A

In the present work, the blend of poly（butylene succinate） （PBS） and bisphenol A （BPA） was prepared by solution mixing, and the intermolecular interactions between the two components were characterized by a combination of nuclear magnetic resonance （NMR） and Fourier transform infrared spectroscopy （FTIR）. The results showed that intermolecular hydrogen-bonding forms between the carbonyl group of PBS and phenol hydroxyl of BPA. With the increase of BPA content, more hydrogen bonds were formed. The effect of hydrogen bonding on the crystallization behavior of PBS was investigated by differential scanning calorimetry （DSC） and polarized optical microscopy （POM）. The results showed that the overall isothermal crystallization kinetics and the spherulite growth rate of PBS decrease with the increase of BPA content, while the PBS spherulite size increases with BPA content.