Abstract: The invention disclosed is an apparatus and method for the recovery of acetic acid, azeotropic agent, extraction agent, re-usable water and other reaction products such as p-toluic acid, from an aqueous stream generated during a terephthalic acid production process, having superior energy efficiency and reduced water consumption.

Abstract: A method for recovering acetic acid from an aqueous feed stream containing acetic acid and, in particular, a stream generated during terephthalic acid production includes feeding a water-rich feed stream to a liquid-liquid extraction column, which includes a guard bed near the top thereof for conversion of alcohol within the feed stream by reaction with acetic acid to the corresponding ester; and removing residual water from acetic acid in an azeotropic distillation column by feeding water-poor feed streams from the extraction column to the distillation column at a height at which the mixture has a similar water concentration. The liquid-liquid extraction column produces an extract comprising an extraction solvent and acetic acid which is sent to the azeotropic distillation column to separate residual water and acetic acid.

Abstract: A method for performing a singular value decomposition (SVD) upon a matrix. The method includes the steps of: (a) simplifying the matrix to derive a simplified matrix; (b) performing an iterative matrix multiplication upon the simplified matrix to generate an iterated matrix; (c) extracting a vector of the iterated matrix according to an iteration number of the iterative matrix multiplication; (d) de-correlating the simplified matrix from the vector to update the simplified matrix; (e) repeating steps (b), (c), and (d) until a predetermined number of vectors have been derived; and (f) storing a first unitary matrix determined according to the predetermined number of vectors in the singular value decomposition.

Abstract: A programmable LDPC (Low-Density Parity-Check) code decoder and decoding method thereof is disclosed. By combining at least one programmable switch and at least one memory unit to decode any quasi-cyclic-based parity check matrix, one can set the switch state of the programmable switch to dynamically adjust the size of the decoding matrix and determine the locations of 1's and 0's in the decoding matrix. The mechanism helps improving the usability and flexibility of the decoding matrix.

Abstract: The invention disclosed relates to an apparatus and method for recovering acetic acid from an aqueous feed stream containing acetic acid, in particular a stream generated during terephthalic acid production. The apparatus includes: a liquid-liquid extraction column to which water-rich feed streams are fed, having a guard bed situated near the top and within the extraction column for conversion by reaction with acetic acid of alcohol within the mixture to the corresponding ester; and an azeotropic distillation column to remove residual water from acetic acid, to which water-poor feed streams are fed directly at a height of the azeotropic distillation column at which the mixture therein has a similar water concentration. The liquid-liquid extraction column produces an extract comprising an extraction solvent and acetic acid which is sent to the azeotropic distillation column to separate residual water and acetic acid.

Abstract: An improved solvent regeneration system for extractive distillation and liquid-liquid extraction processes capable of effectively removing heavy hydrocarbons and polymeric materials that otherwise develop in a closed solvent loop. The improved process employs a light hydrocarbon displacement agent, which is at least partially soluble in the solvent to squeeze the heavy hydrocarbons and polymeric materials out of the solvent, with virtually no additional energy requirement. It has been demonstrated that the light non-aromatic hydrocarbons in the raffinate stream generated from the extractive distillation or the liquid-liquid extractive process for aromatic hydrocarbons recovery can displace not only the heavy non-aromatic hydrocarbons but also the heavy aromatic hydrocarbons from the extractive solvent, especially when the aromatic hydrocarbons in the solvent are in the C10+ molecular weight range.

Abstract: A signal processing method is adapted for dealing with a plurality of vector matrixes to detect the image of a predetermined range, and the vector matrix data are generated by reflecting a plurality of ultrasonic beams in the predetermined range. The signal processing method of the present invention is that summing all vector matrix data in a predetermined time interval so as to generate a total correlation matrix. In addition, obtaining a correlation matrix through the total vector matrix multiplied by a transposed total vector matrix, and obtaining a weight value according to inversion correlation matrix. Then, a weighting operation is performed for the vector matrix data in the predetermined time interval according to the weight value, so as to obtain a weighting operation result for performing an image synthesis procedure.

Abstract: A process and apparatus is provided for reduction of dissolved oxygen content in seawater from about 8 ppm in the feed seawater to about 10 ppb or less. Significant advantages are achieved by: use of a separator in horizontal alignment to provide high gas-liquid contacting area for separation and de-entrainment within the separator, thereby providing higher throughput; and heating seawater to at least 30° C. and up to 60° C., so as to enhance removal of oxygen from seawater; use of once-through fuel gas as stripping gas and its subsequent combustion for heating the seawater provides for high efficiency and reduction of fouling. The combination of these features allows the amount of residual oxygen in deoxygenated seawater to be reduced to below 10 ppb and as low as 2 ppb.

Abstract: An energy-efficient extractive distillation process for producing anhydrous ethanol from aqueous/ethanol feeds containing any range of ethanol employs an extractive distillation column (EDC) that operates under no or greatly reduced liquid reflux conditions. The EDC can be incorporated into an integrated process for producing anhydrous ethanol used for gasoline blending from fermentation broth. By using a high-boiling extractive distillation solvent, no solvent, is entrained by the vapor phase to the EDC overhead stream, even under no liquid reflux conditions. The energy requirement and severity of the EDC can be further improved by limiting ethanol recovery in the EDC. In this partial ethanol recovery design, ethanol which remains in the aqueous stream from the EDC is recovered in a post-distillation column or the aqueous stream is recycled to a front-end pre-distillation column where the ethanol is readily recovered since the VLE curve for ethanol/water is extremely favorable for distillation.

Abstract: An improved solvent regeneration system for extractive distillation and liquid-liquid extraction processes capable of effectively removing heavy hydrocarbons and polymeric materials that otherwise develop in a closed solvent loop. The improved process employs a light hydrocarbon displacement agent, which is at least partially soluble in the solvent to squeeze the heavy hydrocarbons and polymeric materials out of the solvent, with virtually no additional energy requirement. It has been demonstrated that the light non-aromatic hydrocarbons in the raffinate stream generated from the extractive distillation or the liquid-liquid extractive process for aromatic hydrocarbons recovery can displace not only the heavy non-aromatic hydrocarbons but also the heavy aromatic hydrocarbons from the extractive solvent, especially when the aromatic hydrocarbons in the solvent are in the C10+ molecular weight range.

Abstract: The invention disclosed is an apparatus and method for the recovery of acetic acid, azeotropic agent, extraction agent, re-usable water and other reaction products such as p-toluic acid, from an aqueous stream generated during a terephthalic acid production process, having superior energy efficiency and reduced water consumption.

Abstract: A programmable LDPC (Low-Density Parity-Check) code decoder and decoding method thereof is disclosed. By combining at least one programmable switch and at least one memory unit to decode any quasi-cyclic-based parity check matrix, one can set the switch state of the programmable switch to dynamically adjust the size of the decoding matrix and determine the locations of 1's and 0's in the decoding matrix. The mechanism helps improving the usability and flexibility of the decoding matrix.

Abstract: An energy-efficient extractive distillation process for producing anhydrous ethanol from aqueous/ethanol feeds containing any range of ethanol employs an extractive distillation column (EDC) that operates under no or greatly reduced liquid reflux conditions. The EDC can be incorporated into an integrated process for producing anhydrous ethanol used for gasoline blending from fermentation broth. By using a high-boiling extractive distillation solvent, no solvent, is entrained by the vapor phase to the EDC overhead stream, even under no liquid reflux conditions. The energy requirement and severity of the EDC can be further improved by limiting ethanol recovery in the EDC. In this partial ethanol recovery design, ethanol which remains in the aqueous stream from the EDC is recovered in a post-distillation column or the aqueous stream is recycled to a front-end pre-distillation column where the ethanol is readily recovered since the VLE curve for ethanol/water is extremely favorable for distillation.

Abstract: An energy-efficient extractive distillation process for producing anhydrous ethanol from aqueous/ethanol feeds containing any range of ethanol employs an extractive distillation column (EDC) that operates under no or greatly reduced liquid reflux conditions. The EDC can be incorporated into an integrated process for producing anhydrous ethanol used for gasoline blending from fermentation broth. By using a high-boiling extractive distillation solvent, no solvent is entrained by the vapor phase to the EDC overhead stream, even under no liquid reflux conditions. The energy requirement and severity of the EDC can be further improved by limiting ethanol recovery in the EDC. In this partial ethanol recovery design, ethanol which remains in the aqueous stream from the EDC is recovered in a post-distillation column or the aqueous stream is recycled to a front-end pre-distillation column where the ethanol is readily recovered since the VLE curve for ethanol/water is extremely favorable for distillation.

Abstract: The invention disclosed relates to catalytic distillation column internals providing improved liquid reaction mixture and catalyst contacting for simultaneous catalytic reaction and separation of the reaction mixture. The invention is an improved catalytic distillation apparatus providing optimum balance of catalytic reaction and mass transfer steps, wherein distribution, mixing and feeding of liquid reaction mixture to the reaction zone and distillation section are better controlled and more uniformly applied. At least one catalyst bed is situated in at least one receiving pan of a distillation tray so that the tray performs the functions of both of the reaction section and the distillation section of the catalytic distillation column simultaneously within a stage.

Abstract: An energy efficient, high throughput process for aromatics recovery can be readily implemented by revamping existing sulfolane solvent extraction facilities, or constructing new ones, so as to incorporate unique process operations involving liquid-liquid extraction and extractive distillation. Current industrial sulfolane solvent based liquid-liquid extraction processes employ a liquid-liquid extraction column, an extractive stripping column, a solvent recovery column, a raffinate wash column, and a solvent regenerator. The improved process for aromatic hydrocarbon recovery from a mixture of aromatic and non-aromatic hydrocarbons requires transformation of the extractive stripping column into a modified extractive distillation column. The revamping incorporates the unique advantages of liquid-liquid extraction and extractive distillation into one process to significantly reduce energy consumption and increase process throughput.

Abstract: Extractive distillation processes whereby water-soluble extractive distillation (ED) solvents are regenerated and recovered employ improved operations of the extractive distillation column (EDC) so that polar hydrocarbons are recovered and purified from mixtures containing polar and less polar hydrocarbons and measurable amounts of hydrocarbons that are heavier than intended feedstock and/or polymers that are generated in the ED process. The improved process can effectively remove and recover the heavy hydrocarbons and/or remove polymer contaminants from the solvent in a closed solvent circulating loop through mild operating conditions with no additional process energy being expended. With the improved process, the overhead reflux of the EDC may be eliminated to further reduce energy consumption and to enhance the loading and performance within the upper portion of the EDC, especially when two liquid phases exists therein.

Abstract: A multilevel LINC transmitter. The multilevel LINC transmitter comprises a multilevel signal component separator, a phase modulator block, a mixer block, an up-converter block, a predistorter and an RF block. The multilevel signal component separator comprises a multilevel scaler and converts an input signal to phase signals. The phase modulator block and the predistorter are coupled to the multilevel signal component separator. The mixer block is coupled to the phase modulator block and the predistorter. The up-converter block is coupled to the mixer block. The RF block comprises a plurality of power amplifiers coupled to the up-converter block and a power combiner coupled to the power amplifiers.

Abstract: The invention disclosed relates to an apparatus and method for recovering acetic acid from an aqueous feed stream containing acetic acid, in particular a stream generated during terephthalic acid production. The apparatus includes: a liquid-liquid extraction column to which water-rich feed streams are fed, having a guard bed situated near the top and within the extraction column for conversion by reaction with acetic acid of alcohol within the mixture to the corresponding ester; and an azeotropic distillation column to remove residual water from acetic acid, to which water-poor feed streams are fed directly at a height of the azeotropic distillation column at which the mixture therein has a similar water concentration. The liquid-liquid extraction column produces an extract comprising an extraction solvent and acetic acid which is sent to the azeotropic distillation column to separate residual water and acetic acid.

Abstract: An integrated, continuous process for transforming feedstock, e.g., reformate, which contains high levels of benzene into a low-benzene content feedstock that is suitable for gasoline blending initially removes benzene from the reformate by extractive distillation, then partially hydrogenating the high purity benzene into cyclohexane under mild conditions in a one-stage hydrogenation reactor, and thereafter recovering a cyclohexane product with high purity from the hydrogenation reactor effluent in a back-end purification step using extractive distillation. The initial or front-end separation step yields a low-benzene content reformate.