The present invention provides a system for continuous desalination of saline water having variable salinity, the system comprising: (a) a RO stage comprising one or more reverse osmosis pressure vessels, said first RO stage configured to receive a feed stream of saline water to thereby produce a first reject stream and a first permeate stream, wherein the permeate stream contains less salinity relative to the reject stream; (b) a second RO stage comprising one or more reverse osmosis pressure vessels, said second RO stage being configured to receive the first reject stream to thereby produce a second reject stream and a second permeate stream; (c) a variable pressurizing means located upstream of said RO stages, said variable pressurizing means capable of adjusting the pressure of said feed stream; and (d) a pressure recovery means configured to recover energy from said second reject stream, said pressure recovery means capable of adjusting the pressure of said feed stream. The present invention further provides a method for performing the same.
There is disclosed a process of recovering water from waste water generated by an aromatic acid purification process. The waste water contains salts and organic acids. The process comprises the step of passing a feed stream of said waste water through a reverse osmosis membrane at a temperature equal to, or higher than, the saturation temperature of the salts and organic acids in said waste water to produce a permeate stream. The permeate stream has less salts and organic acids relative to the feed stream.
C02F 1/44 - Traitement de l'eau, des eaux résiduaires ou des eaux d'égout par dialyse, osmose ou osmose inverse
B01D 61/00 - Procédés de séparation utilisant des membranes semi-perméables, p. ex. dialyse, osmose ou ultrafiltrationAppareils, accessoires ou opérations auxiliaires, spécialement adaptés à cet effet
C02F 1/58 - Traitement de l'eau, des eaux résiduaires ou des eaux d'égout par élimination de composés spécifiés dissous
C02F 103/26 - Nature de l'eau, des eaux résiduaires ou des eaux ou boues d'égout à traiter provenant du traitement de plantes ou de parties de celles-ci
3.
PROCESS FOR THE TREATMENT OF WASTE WATER GENERATED IN AN AROMATIC ACID PRODUCTION PROCESS
There is disclosed a treatment process for removing insoluble aromatic acids, heavy metal oxidation catalysts, metal impurities, from waste water generated in an aromatic acid production process. The treatment process comprises the steps of: (a) filtering the waste water to recover the insoluble aromatic acids; (b) passing the filtrate of step (a) through an ion exchange resin to selectively remove at least one heavy metal impurity; and (c) passing the effluent of step (b) through an ion exchange resin to selectively remove said oxidation catalysts.
B01D 15/04 - Procédés de séparation comportant le traitement de liquides par des adsorbants ou des absorbants solidesAppareillages pour ces procédés par des substances échangeuses d'ions comme adsorbants
C02F 9/08 - Traitement en plusieurs étapes de l'eau, des eaux résiduaires ou des eaux d'égout une étape au moins étant un traitement physique
C02F 103/26 - Nature de l'eau, des eaux résiduaires ou des eaux ou boues d'égout à traiter provenant du traitement de plantes ou de parties de celles-ci
C02F 1/42 - Traitement de l'eau, des eaux résiduaires ou des eaux d'égout par échange d'ions
There is disclosed a method for stabilizing hydroxy acid polymer comprising the steps of (a) adding an organic peroxide to a hydroxy acid polymer melt composition containing catalyst that catalyses the polymerization reaction to form the hydroxy acid polymer; and (b) adding at least one stabilizing agent to the hydroxy acid polymer melt composition, wherein said stabilizing agent is selected to at least partially reduce the rate of depolymerization of the hydroxy acid polymer within said melt composition.
There is disclosed a process for producing a polyester copolymer. The process comprises the step of condensating a hydroxyacid, a diol, a dicarboxylic acid and a functionalizing agent selected to form a prepolymer having a polyester copolymer backbone with arms comprising cross-linkable groups extending therefrom. The process also comprises the step of coupling said prepolymer in the presence of a coupling agent to cross link the arms of plural prepolymer backbones and thereby form said polyester copolymer comprising said plural straight chain polyester copolymers coupled to each other by said cross-linked arms. The polyester copolymer may be biodegradable and may be used as a modifier to increase the strength of polylactic acid.
C08G 63/00 - Composés macromoléculaires obtenus par des réactions créant une liaison ester carboxylique dans la chaîne principale de la macromolécule
C08G 63/12 - Polyesters dérivés soit d'acides hydroxycarboxyliques, soit d'acides polycarboxyliques et de composés polyhydroxylés dérivés d'acides polycarboxyliques et de composés polyhydroxylés
C08G 18/42 - Polycondensats contenant des groupes ester carboxylique ou carbonique dans la chaîne principale
C08G 63/16 - Acides dicarboxyliques et composés dihydroxylés
C08L 67/00 - Compositions contenant des polyesters obtenus par des réactions créant une liaison ester carboxylique dans la chaîne principaleCompositions contenant des dérivés de tels polymères