33 results about "Sub-bituminous coal" patented technology

A method of cement clinker manufacture comprises feeding a clinker feed material containing a source of calcium carbonate into a feed end of a cement kiln, the feed material is heat processed in the kiln to produce cement clinker with emission of carbon dioxide from thermal decomposition of said source of calcium carbonate and discharge of the carbon dioxide from the kiln, and cement clinker is discharged from a discharge end of the kiln; a coal ash derived from burning pulverized lignite or sub-bituminous coal is included in the feed material fed into the feed end to replace a portion of the source of calcium carbonate, and provides a source of calcium as well as other components notably silicon and aluminum, in the formation of the cement clinker, with a lowering of the emission of carbon dioxide in the kiln, per unit weight of cement clinker produced.

This method for manufacturing carbon fibers is provided with: a step for separating ashless coal obtained from bituminous coal or sub-bituminous coal into soluble components and insoluble components using a solvent extraction process; a step for heat-treating the soluble components; a step for melt-spinning the heat-treated soluble components; a step for infusibilizing the strands obtained by melt-spinning; and a step for carbonizing the infusibilized strands.

This invention relates to a catalytic oxidation smoke gas mercury removing method, which is used for controlling and reclaiming the gas mercury, especially for the brown coal and subbituminous coal smoke gas. The method uses the mercury oxidative catalyst and the adsorbent to oxygenize and absorb mercury in the smoke gas, then dissociate and elution the mercuric oxide in high temperature to regenerate it. The heat of the elution gas can be reclaimed by residual heat utilization device, and the high concentration mercury will be reclaimed through cold-trap or processed by the agent in the mercury reactor. The reclaimed mercury and other by-product can be sold to reduce the cost. Said invention uses the thermal instability of the mercuric oxide, and reclaims in the relative lower temperature; the recovery ratio can reach to 98%, meanwhile, it processes post-treatment with the mercury and has no secondary pollution.

A process and system is provided for briquetting particulate matter such as moisture-containing bituminous and sub-bituminous coal. This process includes partially drying the particulate matter and feeding, the partially dried particulate matter to a briquetting apparatus under conditions such that water vapor is released from the particulate matter during feeding. The particulate matter is passed through briquette forming rollers to form briquettes. The released water vapor substantially displaces or prevents the ingress of a large proportion of other gaseous components from the atmosphere surrounding an / or intermixed with the particulate matter. The particulate matter that is fed to the briquetting apparatus is surrounded by and intermixed with a gaseous component containing 70% to 100% by volume of water vapor at the point where it enters the briquette-forming part of the briquetting apparatus, such that when the particulate matter is compressed during briquette formation, the water vapor liquefies and the pressure buildup of gaseous material in the thus-formed briquettes is minimised. This reduction in the pressure buildup of gaseous components also acts to reduce blow-back of gases as the coal fines are being formed into briquettes.

Powder components containing calcium, alumina, silica, iron, magnesium, and a halogen sorbent are used in combination during coal combustion to produce environmental benefits. Sorbents are added to the coal ahead of combustion and / or are added into the flame or downstream of the flame. The alkalinity and chlorine of the powder is minimized in order to mitigate unwanted fouling, especially when used with sub-bituminous and lignite coals.

The present invention relates to a process for the preparation of blue-fluorescence emitting carbon dots (CDTs) from sub-bituminous tertiary high sulfur Indian coals. More particularly, the present invention relates to the production of characteristics carbon dots from low-quality Indian coals by an ultrasonic-assisted wet-chemical method. Also, the present invention provides a simple and environmentally benign method for fabrication of characteristics and size-controlled carbon dots.

The invention discloses a selective flocculation-reverse flotation ash content decreasing method for ultrafine-grained sub-bituminous coal. The method is a method that preselection is conducted in a conventional sub-bituminous coal reverse flotation method and comprises the steps that firstly, sodium hexametaphosphate is added, and size mixing, dispersing and stirring are conducted; secondly, dextrin is sequentially added to serve as an inhibitor, and stirring is conduced; thirdly, a non-ionic polymeric flocculant (PAM) is added, and stirring is conducted; fourthly, a foaming agent methyl isobutyl carbinol (MIBC) is added, and stirring is conducted; and fifthly, a collecting agent compound ammonium salt is added, and air inflating and bubble scraping are conducted simultaneously. According to the method, under the condition of the same collecting agent, the ash content of clean coal can be effectively decreased, consumption of the collecting agent is reduced, the reverse flotation separation efficiency of the sub-bituminous coal is improved, and the purposes of decreasing the ash content of the ultrafine-grained sub-bituminous coal and improving the quality of the ultrafine-grained sub-bituminous coal are achieved.

In the invention, two kinds of waste material dry dust discharging coal ash and desulfurize gyp produced by power plant burning sub-bituminous coal or lignitous coal are used as main composition, shell and or cement, calcined gypsum and aluminum sulfate or alunite are used as secondary composition, they are prepared to dry powder soil curing agent by weighing, matching, forced stirring and mixing. The soil can be concreted by mixing a proper quantity of curing agent into the soil and processes of stirring, compacting, soaking and maintaining.

The invention discloses a preparation method of high-adsorptivity coal-base pressed block activated carbon. The preparation method comprises the following steps: carrying out coal blending on 60-80 wt% of main coal, 10-20 wt% of sub-bituminous coal and 10-20 wt% of gas-fat coal, and pulverizing to obtain raw material coal, wherein the main coal is non-caking coal and / or jet coal; and carrying out pressure molding and granulation on the obtained raw material coal, and carrying out oxidation treatment, carbonizing treatment and activating treatment, thereby obtaining the activated carbon. The activated carbon, which is prepared by carrying out coal blending on certain amounts of the main coal, sub-bituminous coal and gas-fat coal, well combines the properties and interactions of the coals. Compared with the traditional coal-base activated carbon, the adsorptivity of the high-adsorptivity coal-base pressed block activated carbon is obviously enhanced, thereby solving the common problem of poor adsorptivity in the traditional coal-base pressed block activated carbon production process.

The invention discloses a preparation method of a low-rank coal-based high-efficiency water reducer, which belongs to the technical field of low-rank coal resource utilization and fine chemical industry. The present invention uses low-rank coal such as lignite and sub-bituminous coal as raw materials, obtains sulfonated coal through sulfite sulfonation, then obtains sulfonated coal-based humic acid through liquid-phase oxidative cracking of sulfonated coal, and finally sulfonated coal-based humic acid is obtained. The humic acid is polycondensed by formaldehyde into coal-based humic acid superplasticizer. The method for synthesizing high-efficiency water-reducing agent using low-rank coal such as lignite and sub-bituminous coal as raw materials provided by the invention has the characteristics of high yield of sulfonated coal-based humic acid and water-reducing agent, low cost, clean process, and the like. The coal-based humic acid water-reducing agent has good dispersion, water-reducing and slump-preserving properties, and the water-reducing effect is better than the commercially available naphthalene-based superplasticizer. Under the condition of the dosage of 0.4%, the water reduction rate can reach up to 24.5%, the initial cement slurry fluidity is 162mm, the mortar fluidity is 305mm, and the 2h mortar fluidity loss rate is 6.9%.

The present invention addresses the problem of providing a raw material pitch for carbon fiber production with which it possible to produce carbon fibers having excellent tensile strength relatively inexpensively. This raw material pitch for carbon fiber production is a pitch obtained from coal for producing carbon fibers by melt spinning, the raw material pitch for carbon fiber production characterized in that the content of oxygen is 1.0 mass% or higher, and the content of toluene solubles is 20 mass% or higher. The coal may be bituminous or sub-bituminous coal. The raw material pitch for carbon fiber production may be obtained by heat treatment of a soluble component separated from a thermal decomposition product of coal in a solvent by solvent extraction treatment at a temperature of less than 300C, at a temperature of 150C or higher.