Abstract:
Disclosed are a method for preparing a non-sintered shell-wrapped ceramsite using solid waste meanwhile immobilizing a heavy metal in river sediment, and a non-sintered river-sediment-based shell-wrapped ceramsite, which relate to the technical field of building materials. The disclosure combines river sediment with a solid waste powder and an alkali activating powder material, and adopts multiple-step granulations to realize particle size control and physical pore formation, thereby obtaining a non-sintered ceramsite. A sulfoaluminate cement and a Portland cement are used to encapsulate the non-sintered ceramsite and form a shell by wrapping, thereby preparing a non-sintered river-sediment-based shell-wrapped ceramsite with internal porosity and dense shell.
Abstract:
An amount-reduction, harmless, disposal method for heavy metal waste gypsum (HMWG), which belongs to the technical fields of recycling economy and environmental protection. The HMWG used as raw material is subjected to processes of smelting fluxpreparation, lead smelting, fuming, and geopolymeric gelling, to realize amount-reduction, harmless and resources recycling utilization of heavy metal waste gypsum. The smoke containing sulfur dioxide produced in the smelting process is sent to the acid making system, and the produced dust with heavy metal is sent to the dedicated system for heavy mental disposing. The smoke dust produced in the fuming process is returned to the lead smelting system. The secondary HMWG produced in the acid making system would be returned to the preparation process of smelting flux. And the final products would be sulfuric acid and geopolymer material.
Abstract:
Systems and methods of the present invention include a method for the treatment of drilling wastes and coal combustion residues, comprising combining at least a first drilling waste with coal combustion residues to form a paste, combining at least a second drilling waste with coal combustion residues to form a compactable fill, and placing the paste and the compactable fill in a landfill. Other embodiments include a method of treating drilling wastes and coal combustion residues, comprising combining at least one drilling waste with a coal combustion residue to form a paste. Further embodiments include containing the paste within at least one geotextile container. Still further embodiments include placing the geotextile container in a landfill.
Abstract:
The present invention relates to a method for recycling waste water from a stainless steel slag treatment process wherein stainless steel slag is brought into contact with water, in particular to neutralize the free lime contained therein, thereby producing said waste water. This waste water contains heavy metals, including at least chromium, and has a pH higher than or equal to 11. In accordance with the invention, it is used as production water for manufacturing mortar and/or concrete. In this way, the heavy metals, which are dissolved in the waste water and thus readily available, become bound in the newly formed cement phases so that they are prevented from leaching. Moreover, it has been found that the workability of the fresh mortar or concrete and also the quality of the final mortar or concrete materials is not negatively affected by the use of this alkaline waste water and that an accelerated setting could be achieved during the first hours.
Abstract:
The present disclosure describes solid waste forms and methods of processing waste. In one particular implementation, the invention provides a method of processing waste that may be particularly suitable for processing hazardous waste. In this method, a waste component is combined with an aluminum oxide and an acidic phosphate component in a slurry. A molar ratio of aluminum to phosphorus in the slurry is greater than one. Water in the slurry may be evaporated while mixing the slurry at a temperature of about 140-200° C. The mixed slurry may be allowed to cure into a solid waste form. This solid waste form includes an anhydrous aluminum phosphate with at least a residual portion of the waste component bound therein.
Abstract:
[Problems] To provide an inorganic electrolyte setting agent capable of blocking hazardous heavy metals almost permanently and further usable as resources, based on the geological balance of elements, and a treating method for utilization as resources using the same.[Means for Solving the Problem] There is provided an inorganic electrolyte setting agent capable of rendering heavy metal ions nonhazardous, including an aqueous solution as a main agent mixed with A below and also at least one of B and C below: (A) sulfuric acid, (B) at least one of aluminum sulfate and polyaluminum sulfate, (C) at least one of polyferric sulfate and ferric chloride; and an aqueous solution as a concomitant agent mixed with D below: (D) at least one of potassium silicate and sodium silicate.
Abstract:
Compositions are provided for increasing the electrical conductivity of concrete or controlled low-strength materials (flowable fill). One composition sets to produce a concrete and includes portland cement, water, aggregate, and particulate matter including a sorbent and a contaminant absorbed, adsorbed or entrapped by the sorbent. The sorbent may be activated carbon, and the contaminant may be mercury or a compound containing mercury. Another composition is a self-compacting, cementitious flowable fill composition that includes portland cement, water, and particulate matter including a sorbent and a contaminant absorbed, adsorbed or entrapped by the sorbent. The sorbent may activated carbon, and the contaminant may be mercury or a compound containing mercury. The compositions may also include carbon fibers.
Abstract:
Process for rendering inert a sludge (1) comprising heavy metals and organic matter, according to which phosphoric acid (2) is added to the sludge and the latter is subjected to calcination (6). A hydraulic binder (9) is mixed with the product of the calcination (7) and mixed with water (8). The resulting mixture (11) is subjected to setting and curing.
Abstract:
The invention provides methods of remediating lead and other heavy metals in ammunition traps and shooting ranges. One or more remediation agents is added to a trap or a shooting range. The remediation agent(s) interact with and “fix” heavy metals, rendering them substantially non-leachable. An improved ammunition trap is also provided.
Abstract:
A process for chemical fixation of radionuclides and radioactive compounds present in soils, solid materials,sludges and liquids. Radionuclides and other radioactive compounds are converted to low-temperature Apatite-Group structural isomorphs (general composition: (AB).sub.5 (XO.sub.4).sub.3 Z), usually phosphatic, that are insoluble, non-leachable, non-zeolitic, and pH stable by contacting with a sulfate, hydroxide, chloride, fluoride and/or silicate source and with a phosphate anion in either a one or two step process. The Apatitic-structure end product is chemically altered from the initial material and reduced in volume and mass. The end product can be void of free liquids and exhibits sufficiently high levels of thermal stability to be effective in the presence of heat generating nuclear reactions. The process occurs at ambient temperature and pressure.