Abstract:
A method for using alkali for recovering amine used in a process for breaking emulsions and sludges. The amine has an inverse critical solution temperature with water. The process breaks a sludge into a water component containing residual amine and oil component if oil is present in the original sludge, and a solid matter component. The present invention uses alkali to minimize the amount of amine lost in the water component and in the solid matter component.
Abstract:
A process for the production of a thermoplastic composition for molded parts having improved impact resistance, transparency, surface gloss, and weatherability, and formed of a hard inner core of crosslinked polystyrene, a rubber-elastic intermediate layer of crosslinked polyacrylic ester, and an outer layer of polyvinyl chloride, wherein the inner core thereof is produced by the steps of:(a) forming a mixture, before or after addition of an initiator, under polymerization conditions in the presence of an emulsifier, of 0.01-5.0% by weight of an acrylic acid or methacrylic acid aclkyl ester with a crosslinking component, and thereafter(b) adding to the mixture, 20-70% by weight of a mixture of an aromatic vinyl monomer with a crosslinking component and, simultaneously therewith in a separate stream, a solution of an organic complexing agent and of an emulsifier in water, and optionally a solution of a catalyst, and emulsion polymerizing the resultant mixture;wherein the intermediate layer thereof is produced by adding, to the inner core produced in step (b),(c) 79.99-25% by weight of a mixture of an acrylic acid alkyl ester with a crosslinking component and simultaneouly therewith an aqueous emulsifier solution, under emulsion polymerization conditions; andwherein the outer layer thereof is formed on the thus-produced core/shell polymer by adding, to 50 to 2 parts by weight thereof,(d) 50 to 98 parts by weight of vinyl chloride or a monomer mixture containing predominantly vinyl chloride, with agitation, and in the presence of an initiator, the agitating temperature and period selected so that the conversion, based on the monomer mixture or, respectively, the vinyl chloride, is at most 10% by weight, and thereafter continuing the polymerization by heating to the polymerization temperature, to a vinyl chloride conversion of 65-95%.
Abstract:
Heavy metals and compounds thereof and other toxic materials in industrial wastes, sludges, soils, incinerated ashes and the like are fixed and stablized in a char residue, obtained by critical region pyrolyzing techniques and appropriate proportions of cabonaceous materials intimately mixed with the sludge, to encapsulate the heavy metals with carbon bonded thereto which effectively detoxifies the residue and renders it immune to any substantial leaching out or later exposure to the toxic metals, such that the same is environmentally safe for such uses as landfill and the like.
Abstract:
A process for recovery of energy from waste and residues is disclosed. The residues, after sieving, are subjected to bacterial digestion in a methanization reactor and the solid phase of the digestate is then subjected to incineration in a furnace supplying a heat recuperator, the furnace being supplied with complementary combustible by the methane coming from the digester, while the circuit of the fumes downstream of the recuperator is used for heating by at least one secondary circuit, the magma in the course of treatment in the digester and/or the sludge separated from the digestate before recycling thereof towards the digester.
Abstract:
An apparatus and method for dewatering sludges and the like as part of landfill operations by electrokinetic techniques including placing anode and cathode electrode modules in contact with the sludge and applying electrical energy to the electrodes to establish an electric field in the sludge. Charged particles within the sludge, including macro-molecules, colloids, and suspended particles, electrophoretically migrate to the oppositely charged counter electrode and consolidate. A filtration media located at one of the electrodes permits the electro-osmotic removal of water from the sludge to encourage solids densification. The electrical energy applied to the electrodes is a chopped, time-varying, intermittent unidirectional current having a rapid rise edge which provides dewatering results comparable to prior methods that used direct current or full AC current but at substantially reduced energy consumption to provide more economical dewatering. Presently preferred optimum conditions for practicing the invention are also disclosed, including means for applying the techniques of the disclosure to a continuous dewatering method and an apparatus for practicing that method. The application of the electrokinetic techniques to other processes such as electrodialysis, including electrolysis (using a membrane or bipolar membrane), desalinization or metathesis; and electrowinning, including electroplating; and other electrophoretic processes is suggested.
Abstract:
In the aerobic digestion of sludges, particularly but not exclusively primary sedimentation sewage sludges, a layer of sludge foam is deliberately maintained over the sludge surface to improve the efficiency of the process. The layer of foam may have a volume of at least 50% of that of the sludge. The digestion process is effected in a digester, in which the amount of foam may be reduced (as necessary) by injecting sludge directly into the foam to cause local collapse thereof. A digester vessel especially suited for use in the process is described.
Abstract:
According to the process, a clay material is first dispersed with stirring in the waste (or vice versa) between 0.degree. and 150.degree. C. then, in particular in the case of acidic wastes, it is neutralized to an approximately neutral pH by a product preferably with a lime base and, in a third phase, a hydraulic and/or calcium binder is added to the mixture. Application to petrification of all types of wastes of industrial, mining, urban and other origins.
Abstract:
A solid fixation product of harmful, water-containing waste materials and cement, which product is highly resistant to leaching by water and salt solutions. The product has a high content of 20 to 50% of waste materials based on the dry weight of the waste in the product and a water content corresponding to a water-to-cement ratio of 0.2 to 0.45. The method according to the invention which permits producing of such products is characterized in that evaporation of the water-containing waste materials and the mixing with the fixation matrix takes place concurrently at temperatures of 100.degree. to 180.degree. C. The resulting solid fixation product is of relatively small volume and, accordingly, requires only relatively little storage space.
Abstract:
A method for treating aqueous liquid and semi-liquid wastes by solidification comprising the steps of mixing with the waste a dry water-reactive solidification agent comprising cement, a dry water absorbent material, and a powdered alkali metal silicate in a quantity sufficient to convert the mixture into a chemically and physically stable solid end product substantially insoluble in water and which contains no substantially free-standing water, and allowing the mixture to set to a sedentary mass. Additive agents such as surfactants, fixatives, waterproofing agents, coloring agents, and the like are also disclosed as assisting in the solidification reaction by reacting with certain constituents in the waste.