During lightweight aggregate (LWA) production through sintering process, formation of liquid phase captures emitted gas to form pores in the LWA and leads to successful bloating. As the LWA undergoes sintering in the kiln, the liquid phase starts to form on the LWA surface. Accordingly, in a rotary kiln where the LWA are continually rolling over each other, the touching surfaces of LWAs with liquid phase start to adhere together and form lumps of LWA exiting the furnace. This method prevents agglomeration of spherical LWA during sintering. The LWA can be produced from clay, slate, shale, and potentially other waste materials. This method results in production of discrete spherical LWA particles that can be coated with waste fly ash particles to form a thin layer on the surface of LWA that will not melt during sintering and will prevent touching surfaces of LWA particles from sticking together and forming lumps.

A method for recycling a magnesia carbon brick includes bringing a used magnesia carbon brick containing an aluminum-containing substance into contact with water, followed by subjecting the used magnesia carbon brick to a dehydration treatment and pulverizing the used magnesia carbon brick subjected to the dehydration treatment for reusing as a refractory raw material. The corrosion resistance of a refractory made of a used magnesia carbon brick is improved when the used magnesia carbon brick is reused as a refractory raw material.

A method and apparatus for treating waste materials comprising, particulating the waste materials into discrete particles, heating and drying the particles in a non-oxidizing atmosphere in a drier at a temperature in the range of 800 to 860 C. for carbonizing the particles, crushing the carbonized particles and leaching the crushed carbonized particles in an acid solution for dissolution of heavy metals into the solution, separating the leach solution containing heavy metal from the carbonized particles, adding to the carbonized particles particulate sodium hydroxide, silica, feldspar and limestone in a ratio of 100:0.3-0.5:8-12:2-4, mixing said particles with 15 to 18% by weight water to form a wet mixture and continuously extruding the wet mixture to form an elongated continuous extrusion, severing the elongated extrusion into blocks or planks of predetermined length, drying the blocks or planks and heating the dried blocks or planks in a kiln at a temperature in the range of 1200 to 1300 C. for a time sufficient in an oxygen deficient atmosphere to sinter the blocks or planks and to form carbides, and separating and recovering CO.sub.2 gas from combustion gases in the kiln.

The present invention relates to lightweight high strength microsphere containing ceramic particles having controlled microsphere placement and/or size and microsphere morphology, which produces an improved balance of specific gravity and crush strength such that they can be used in applications such as proppants to prop open subterranean formation fractions. Proppant formulations are further disclosed which use one or more microsphere containing ceramic particles of the present invention. Methods to prop open subterranean formation fractions are further disclosed. In addition, other uses for the microsphere containing ceramic particles of the present invention are further disclosed, as well as methods of making the microsphere containing ceramic particles.

The present invention relates to a method for manufacturing a ceramic foam and the ceramic foam thus obtained, using raw material obtained from mining tailings, a fluxing agent, and glycerol as the sole foaming agent.

Ceramic particles for use in a solar power tower and methods for making and using the ceramic particles are disclosed. The ceramic particle can include a sintered ceramic material formed from a mixture of a ceramic raw material and a darkening component comprising MnO as Mn.sup.2+. The ceramic particle can have a size from about 8 mesh to about 170 mesh and a density of less than 4 g/cc.

The invention relates to a batch for the production of a carbon bonded product and to a process for the production of a carbon bonded product.

A device and method of reclaiming refractory material from a lining of a refractory includes assembling a first refractory component of the lining with a first refractory product, and assembling a second refractory component of the working lining with a second refractory product different from the first refractory product, the second refractory product including magnetic material dispersed therein. Upon the lining reaching a service life, the lining is demolished to produce a mixture of the first refractory component pieces and the second refractory component pieces. Magnetic separation is performed on the mixture to separate the second refractory component pieces from the first refractory component pieces.

The invention relates to a process for the preparation of a ceramic article containing industrial, domestic or natural sludge, the ceramic article, and treated domestic or natural sludge suitable as raw material for the production of the ceramic article. The sludge (which definition excludes digestate that is obtained from a Municipal Solid Waste (MSW) process comprising liquefaction of the organic fraction of MSW by addition of one or more enzymes) has been pretreated by a process comprising the optional step of drying the sludge to a moisture content of at most 10% by weight, resulting in dried sludge, and heating the sludge or dried sludge in a spouting bed incinerator and reducing the content of organic matter to less than 5% by weight. The invention furthermore relates to a process wherein the pretreatment comprises using the domestic or natural sludge as a food source for larvae.

In some variations, the invention provides a biocarbon composition comprising a low fixed carbon material with a fixed carbon concentration from 20 wt % to 55 wt %; a high fixed carbon material with a fixed carbon concentration from 50 wt % to 100 wt % (and higher than the fixed carbon concentration of the low fixed carbon material; from 0 to 30 wt % moisture; from 0 to 15 wt % ash; and from 0 to 20 wt % of one or more additives (such as a binder). Some variations provide a process for producing a biocarbon composition, the process comprising: pyrolyzing a first biomass-containing feedstock to generate a low fixed carbon material; separately pyrolyzing a second biomass-containing feedstock to generate a high fixed carbon material; blending the low fixed carbon material with the high fixed carbon material, thereby generating an intermediate material; optionally, blending one or more additives into the intermediate material; optionally, drying the intermediate material; and recovering a biocarbon composition containing the intermediate material or a thermally treated form thereof.