The present invention provides a fiber-reinforced cement composition comprising; cement, fiber, silica, filler, expanded perlite, and polymer. The fiber-reinforced cement composition according to the present invention has low density, high toughness and flexural strength, and not contains volatile composition. When it is molded into workpiece, the workpiece is lightweight, easy to be cut and/or lathed into desired shapes, drilled and fixed with screws and/or repeatedly nailed at the same position, tolerant to humidity, termites and insects, inflammable and does not produce powder when cut, drilled and/or lathed that is hazardous to the workers. Therefore, it is suitably applicable for being utilized as a material for manufacturing furniture parts.

The present invention provides a fiber-reinforced cement composition comprising; cement, fiber, silica, filler, expanded perlite, and polymer. The fiber-reinforced cement composition according to the present invention has low density, high toughness and flexural strength, and not contains volatile composition. When it is molded into workpiece, the workpiece is lightweight, easy to be cut and/or lathed into desired shapes, drilled and fixed with screws and/or repeatedly nailed at the same position, tolerant to humidity, termites and insects, inflammable and does not produce powder when cut, drilled and/or lathed that is hazardous to the workers. Therefore, it is suitably applicable for being utilized as a material for manufacturing furniture parts.

Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

A composite material, compositions, processes and methods of using coal and coal by-products composite ceramics is provided for use as a safe, non-toxic material for construction, building and architecture components. The composite material disclosed herein is formed from resin/coal aggregates that contain and prevent the release of harmful impurities that naturally occur in both coal and coal by-products while the advantages of coal-based composites are made available to the building industry. The strength, density and porosity of the composites can be tailored within a wide range to fit the final application by controlling the materials, form factor and processing parameters during fabrication.

A composite material, compositions, processes and methods of using coal and coal by-products composite ceramics is provided for use as a safe, non-toxic material for construction, building and architecture components. The composite material disclosed herein is formed from resin/coal aggregates that contain and prevent the release of harmful impurities that naturally occur in both coal and coal by-products while the advantages of coal-based composites are made available to the building industry. The strength, density and porosity of the composites can be tailored within a wide range to fit the final application by controlling the materials, form factor and processing parameters during fabrication.

A structural barrier and energy absorbing device comprises a plurality of structural elements. The structural element alone or in a plurality may serve as a traversal impediment or energy absorbing device, such as a pedestrian barrier, vehicular barrier, anti-tank obstacle, ballistic barrier, or the like. The structural element may be a tetrapod such that it comprises an element body having four extension portions that extend outwardly from the interior center to a distal end, such that the structural element maintains an identical orientation and a low center of gravity in each of four resting positions. The structural element may be a solid-state structural element comprised of a particular material or a portable and collapsible structural element wherein the element body comprises an outer skin defining an interior void space, such that during set-up or installation the interior void space may be filled with a filler substance onsite.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Disclosed herein are improved methods for recycling used engine oil (UEO). The method includes steps of, mixing UEO, a superplasticizer, and water to give a suspension; mixing aggregates, ordinary Portland cement (OPC), fly ash, silicate fume, and the water to give a first mixture; adding the suspension to the first mixture to give a second mixture; and molding and curing the second mixture into a concrete. The thus produced concrete contains up to 5% of UEO (by weight of total cementitious material) and exhibits comparable compressive properties as to that of ordinary concrete.

A geopolymeric material is described having compressive strength at 28 days ranging from 15 to 100 N/mm.sup.2, obtainable by curing for 12 hours at a temperature ranging from 20° C. to 60° C., from a geopolymeric aqueous mixture comprising the following inorganic components in the following parts by dry mass: metakaolin 1565 potassium silicate and/or sodium silicate 2040 aggregates recycled from CDW (Construction and Demolition Waste) 5300; said geopolymeric aqueous mixture is obtainable by mixing 20175 parts by mass of water with said inorganic components, and has a viscosity at 23° C. between 100 and 10000 Pa.Math.s, wherein: i) the viscosity is measured via Brookfield methodology, ii) the aggregates recycled from CDW belong to one or more of the classes 17.01.01, 17.01.02, 17.01.03, 17.01.07 according to the European Waste Catalogue, iii) the aggregates recycled from CDW have a grain size less than or equal to 4 mm, preferably less than or equal to 2 mm.