Abstract: A method for quickly starting up a reactor and a reactor system therefor are provided. A shell-and-tube reactor in the system is adapted to circulate a heat medium having a solid point in the range of 50-250° C. to the outside of the reaction tubes and characterized by initiating temperature elevation of the reactor by introducing a gas of a temperature in the range of 100-400° C. to the reaction tubes' side and then circulating the heat medium in a heated state to the outside of the reaction tubes. By introducing a gas of an elevated temperature preparatorily to the reaction tubes, it is made possible to prevent the heat medium after circulation from being solidified again and enable the reactor to be quickly started up.

Abstract: The present invention provides an apparatus for producing (meth)acrylic acid and a process for producing (meth)acrylic acid with this apparatus wherein the apparatus enables the production of (meth)acrylic acid stably for a long period of time by effectively inhibiting the polymerization of (meth)acrylic acid in its production process (for example, in a reboiler). At least a part of the apparatus is made of a nickel-chromium-iron alloy with a molybdenum content of 3 to 20 mass %, but not including 3 mass %, or with a molybdenum content of 1 to 4 mass % and a copper content of 0.5 to 7 mass %.

Abstract: The present invention provides a process for producing a water-absorbent resin of which the residual monomer content and the extractable content are low. The process for producing a water-absorbent resin comprises the step of polymerizing at least one monomer component including acrylic acid and/or its salt as major components to produce a water-absorbent resin that is a neutralized salt, and this process is characterized in that the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane and has a protoanemonin content of not more than 10 ppm, and in that the resultant water-absorbent resin has a neutralization ratio of not less than 50 mol %.

Abstract: A method for quickly starting up a reactor and a reactor system therefor are provided. A shell-and-tube reactor in the system is adapted to circulate a heat medium having a solid point in the range of 50-250° C. to the outside of the reaction tubes and characterized by initiating temperature elevation of the reactor by introducing a gas of a temperature in the range of 100-400° C. to the reaction tubes' side and then circulating the heat medium in a heated state to the outside of the reaction tubes. By introducing a gas of an elevated temperature preparatorily to the reaction tubes, it is made possible to prevent the heat medium after circulation from being solidified again and enable the reactor to be quickly started up.

Abstract: A method for producing an unsaturated carboxylic ester is provided, which can prevent the raw material compounds and the product of the reaction from splashing and adhering on the inner wall of the reaction vessel and succumbing to polymerization on the inner wall. Specifically, it is characterized by the fact that the difference between the outer periphery of the reaction vessel heated by the heating means and the reaction solution in temperature is not higher than 80° C.

Abstract: The present invention provides a process for producing a water-absorbent resin of which the residual monomer content and the extractable content are low. The process for producing a water-absorbent resin comprises the step of polymerizing at least one monomer component including acrylic acid and/or its salt as major components to produce a water-absorbent resin that is a neutralized salt, and this process is characterized in that the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane and has a protoanemonin content of not more than 10 ppm, and in that the resultant water-absorbent resin has a neutralization ratio of not less than 50 mol %.

Abstract: Provided are a packed column arranged so as to be capable of effectively preventing polymerization of a polymerizable compound such as a (meth)acrylic acid in treating the compound, and a method for treating a polymerizable compound using the packed column. The packed column, which is provided with a packing support plate and is filled with a packing on the packing support plate, is arranged so as to include a packing layer (B) having a greater percentage of voids than that of a packing layer (A), between the packing support plate and the packing layer (A).

Abstract: This invention concerns a method for absorbing acrylic acid, characterized by supplying an acrylic acid-containing reaction gas component obtained by the reaction of catalytic gas phase oxidation to an acrylic acid absorption column and advancing a high boiling inert hydrophobic organic liquid into counter-flow contact with said reaction gas in said acrylic acid absorption column with the mass flow rate of the organic liquid fixed in the range of 0.2-7.0 times the mass flow rate of the acrylic acid in the reaction gas thereby absorbing acrylic acid in said organic liquid and obtaining an acrylic acid-containing solution including a low boiling substance in the range of 0.7-7.5 wt % based on the weight of bottom liquid of absorption column.

Abstract: A process for inhibiting a polymerization of an easily polymerizable compound purification system is disclosed. According to the present invention, the polymerization of the easily polymerizable compound such as (meth)acrylic acid and (meth)acrylate flowed into a vacuum section can be inhibited by contacting a liquid containing a polymerization inhibitor with the compound directly in the vacuum section. When the vacuum section includes a gas and liquid contact chamber (usually a condenser), the liquid containing a polymerization inhibitor may be supplied to the chamber. When the vacuum section includes a liquid ejector and/or a nash pump as a vacuuming device, the liquid containing a polymerization inhibitor may be circulated by the liquid ejector and/or the nash pump for reducing a pressure of a purifying section. Examples of easily polymerizable compounds are (meth)acrylic acid and (meth)acrylates.

Abstract: In an apparatus provided with a plate type heat exchanger as a heater and/or a cooler and operated to treat a gas containing an easily blocking substance, a method for preventing the plate type heat exchanger from being blocked is disclosed which is characterized by i) setting the width of a flow path on a plate of the plate type heat exchanger in the apparatus in a range of 6-25 mm and ii) setting the average flow rate of the gas passing the plate type heat exchanger in the apparatus per unit cross-sectional area of the flow path on the plate in the range of 3-15 m/s. In the exchange of heat of an easily blocking substance by the use of a plate type heat exchanger, a method for preventing the plate type heat exchanger from blockage is disclosed which has the plate type heat exchanger provided in the port for introducing a gas containing an easily blocking substance with a gas dispersion plate.

Abstract: A panel display apparatus comprises a luminance control section for multiplying respective input pixel signals by coefficients corresponding to respective pixels so as to correct dispersion in luminance level between pixels on a plasma display panel caused when display based on signals having the same luminance level is executed, and for thereby generating corrected pixel data. The corrected pixel data is converted into address data in a display data creation section. The address data is supplied to an address driver via a frame memory.

Abstract: A display panel drive device capable of preventing a malfunction caused by the influence of electrical charge remaining in a display-panel discharge cell, in which, in parallel with a switching element that connects each electrode of the display panel to a reference potential, at least one of a row electrode drive circuit and a column electrode drive circuit is provided with a parallel switching element that connects each electrode to the reference potential via a current limiting element. The residual charge in the discharge cell on the display panel is discharged via a bypass formed by this parallel switching element within a predetermined period immediately after the device power supply is turned on.

Abstract: A method for distilling (meth)acrylic acid and/or the ester thereof by withdrawing vapor generated in a distillation column by distillation from the top of the column, condensing the vapor to give a condensate, and circulating part of the condensate as reflux liquid into the distillation column from the top thereof, comprising the step of adding a polymerization inhibitor to said condensate and said reflux liquid. This method enables maintaining the purity and quality of (meth)acrylic acid and/or the ester thereof at a certain level or higher, suppressing generation of polymers in the rectification column and suppressing polymerization of the condensate obtained by distillation in the incident facilities of the column such as condenser, condensate tank, and the like. In addition, the method enables reduction in the amount of polymerization inhibitor used while suppressing polymerization in the intermediate distillation columns (except the final rectification column).

Abstract: The temperature distribution of a heating medium in the reactor is allayed and the occurrence of hot spots is repressed. In a shell-and-tube type reactor provided with donut type and disc type baffle plates, reaction tubes are disposed even in the holes formed in the donut type baffle plates and an empty space devoid of a configuration of the reaction tubes is formed at the center of the shell. According to this invention, (meth)acrylic acid and/or (meth)acrolein can be produced at a low energy by catalytic gas phase oxidation of propylene- or isobutylene-containing gas.

Abstract: A display-panel-drive apparatus having a drive unit that drives the display panel and a control unit that outputs control signals for controlling said drive unit to said drive unit, the display-panel-drive apparatus is provided with: a drive board of the drive unit; a control board of the control unit; a transmission line that transmits the control signals from the control board to the drive board by way of a removable connector; a detection device that detects when said connector is disconnected; and a control device that controls said drive unit when the detection device detects that the connector is disconnected; and wherein the detection device detects that said connector is disconnected by detecting when the connection terminals of the connector are disconnected.

Abstract: A display-panel-drive apparatus having a drive unit that drives the display panel and a control unit that outputs control signals for controlling said drive unit to said drive unit, the display-panel-drive apparatus is provided with: a drive board of the drive unit; a control board of the control unit; a transmission line that transmits the control signals from the control board to the drive board by way of a removable connector; a detection device that detects when said connector is disconnected; and a control device that controls said drive unit when the detection device detects that the connector is disconnected; and wherein the detection device detects that said connector is disconnected by detecting when the connection terminals of the connector are disconnected.

Abstract: A plasma display panel drive apparatus that executes a gradation display by having an address period in which light-emitting cells are set, and a sustain period in which the light-emitting cells that were set in the address period are repeatedly lit up, is provided with: a pulse-output device which outputs a drive pulse to the plasma display panel during the sustain period; a first intensity-level-detection device which detects the average intensity level; a second intensity-level-detection device which detects the intensity level of each discharge cell; and a pulse-voltage-control device which controls the pulse-output device such that the drive-pulse voltage changes based on the average intensity level detected by the first intensity-level-detection device, and the intensity level of each the discharge cell that was detected by the second intensity-level-detection device.

Abstract: There are disclosed an apparatus and a process for purification of an acrylic acid family.

Abstract: A method for managing the operation of an apparatus for the reaction of gas phase partial oxidation of an unsaturated hydrocarbon with a molecular oxygen-containing gas for the purpose of omitting wasteful emergency stop of the operation and ensuring execution of necessary emergency measure and a method for producing (meth) acrylic acid by utilizing the method mentioned above are provided. The operation of the apparatus is brought to emergency stop exclusively when thee values of concentrations of various gases obtained by calculation from the flow rates of the gases being introduced at the inlet port of the reactor and the measured values obtained by analysis with gas analyzing instruments both deviate from the ranges of the present values.

Abstract: A method for distilling a raw material liquid containing (meth)acrylic acid substantially free from azeotropic solvents, collected with a collection agent from a mixed gas obtained by gas phase catalytic oxidation reactions which includes feeding to a distillation column the raw material liquid which temperature is substantially equal to that of the entrance place in the column.