Abstract: In a packed column handling an easily polymerizing substance, the packing with which the column is stuffed is subjected to a water-repelling treatment or a wetting treatment to prevent the easily polymerizing substance in the packed column from polymerizing. By preventing the occurrence of a polymer, it is made possible to ensure continuous production of an easily polymerizing substance-containing solution and decrease the content of the easily polymerizing substance in the product and consequently improve the quality of the product.

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.

Abstract: A method for transferring an easily-polymerizable substance by using a vertically-arranged circulation type canned motor pump or a gas seal type motor pump. Transferring the easily-polymerizable substance such as (meth)acrylic acid with use of the motor pump having the vertically-arranged main shaft enables effective prevention of polymerized matter in the pump. The method assures stable transfer of easily-polymerizable matter for a prolonged time.

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 to produce (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: A program is generated by combining program modules by displaying programs for guiding the combination of program modules and selecting one of the programs. Program modules stored in a memory are displayed on a display device by a command inputted from the input device, navigation programs for guiding the combination of program modules stored in the memory are retrieved by a command inputted from the input device, the retrieved navigation program group are displayed on the display device, a desired navigation program is selected from the navigation program group displayed on the display device, the navigation program is executed, a guide parameter outputted by the navigation program for the combination of program modules is designated, a connector module for combining program modules is generated from the guide parameter inputted from the input device, and the generated connector module is stored in the memory.

Abstract: The present invention provides a method for stabilizing waste oil which is taken of each chemical apparatus of the manufacturing line of (meth)acryl acid and/or ester thereof, and treating the waste oil such as draining it out of the production apparatus, for example, a distillation tower from its bottom, sending and transporting it by a pump through a pipeline, and storing it in a storage tank in a simple manner while keeping the waste oil in a stable state. The waste oil can be stabilized by coexisting with solvent. The solvent used in the present invention is typically at least one selected from the group consisting of water, alcohol, ether, carboxylic acid, ketone, aromatic hydrocarbons, and aliphatic hydrocarbons.

Abstract: In a method for producing acrylic acid by the steps of a reaction of catalytic gas phase oxidation, absorbing the acrylic acid with an absorbent, and dehydrating the acrylic acid-containing aqueous solution, the method is characterized that the step of dehydration comprises adding and an azeotropic solvent, distilling the resultant mixture, and adjusting the acrylic acid concentration at the top of the column in the range of 0.06-0.80 wt. %, thereby preventing the bottoms of the azeotropic dehydration column from substantially containing the azeotropic solvent and water. As results, the acrylic acid is kept from forming a polymer in any of the distillation columns involved in the production, and effective utilization of acrylic acid.

Abstract: A heat exchanger for an easily polymerizing substance-containing gas provided with a shell possessed of a heat-exchanging gas inlet and a heat-exchanging gas outlet and a heat-exchanging part adapted to circulate fluid introduced from outside the shell between the gas inlet and said gas outlet, which heat exchanger is characterized by being provided with a gas distributing plate between the gas inlet and the heat-exchanging part. The heat exchanger is characterized by the gas distributing plate having a cross-sectional area in the range of 1.0-10.0 times the cross-section of the gas inlet. When an easily polymerizing substance-containing gas contacts a structure, the gas is condensed on the contact surface of the structure and suffered to generate a polymer.

Abstract: A storing device is disclosed having a gas-sealing device and/or a heating device provided for a pipe connecting a storing tank for an easily polymerizable and/or coagulating liquid substance and a liquid sealing implement-protecting device. A method for the control of the pressure in the storing device is also disclosed. This invention contemplates protecting a storing device against deformation and fracture.

Abstract: A method and apparatus for preventing contamination of a substrate or a substrate surface, and particularly relates to prevention of contamination of raw materials, semi-finished products, base materials of products and substrate surface in a high-tech industry such as in the production of semiconductors and liquid crystals. A gas coming into contact with a base material or substrate is purified by dust removing apparatus and adsorption and/or absorption apparatus so that the concentration of fine particles in the gas is below class 1,000 and a non-methane hydrocarbon concentration is below 0.2 ppm. Thereafter, the base material or the substrate surface is exposed to this gas.

Abstract: An apparatus for the treatment of a waste gas that is capable of recovering the heat generated by the catalytic oxidation of a waste gas to the largest possible extent and allowing the temperature of the treated gas in a first waste gas pre-heater to be adjusted to an arbitrary level incapable of condensing moisture and/or corrosive gas is provided.

Abstract: A method is disclosed for preventing the polymerization of (meth)acrylic acid and esters thereof, which method is characterized by using an N-nitrosophenyl hydroxyl amine or a salt thereof, an N-oxyl compound, an N-hydroxy-2,2,6,6-tetramethylpiperidine compound, and a 2,2,6,6-tetramethylpiperidine compound in combination in a purifying column. The N-nitrosophenylhydroxylamine or the salt thereof is partly decomposed in the purifying column and is allowed to ascend the interior of the column and effectively inhibit the polymerization of (meth)acrylic acid. Since the method does not need to use any metal compound, it permits the disposal of the waste liquid to be effected easily. Further, the combined use of the relevant components ensures effective prevention of the polymerization in the gas and the liquid phase.

Abstract: A program is generated by combining program modules by displaying programs for guiding the combination of program modules and selecting one of the programs. Program modules stored in a memory are displayed on a display device by a command inputted from the input device, navigation programs for guiding the combination of program modules stored in the memory are retrieved by a command inputted from the input device, the retrieved navigation program group are displayed on the display device, a desired navigation program is selected from the navigation program group displayed on the display device, the navigation program is executed, a guide parameter outputted by the navigation program for the combination of program modules is designated, a connector module for combining program modules is generated from the guide parameter inputted from the input device, and the generated connector module is stored in the memory.

Abstract: It intends to prevent the reduction in quantity with time of an oxyl compound in vinyl compounds. The quantity reduction of the N-oxyl compound is suppressed by causing an N-oxyl compound, N-hydroxy-2,2,6,6-tetramethylpiperidine compound and a 2,2,6,6-tetramethylpiperidine compound to co-exist in vinyl compounds.

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: In a method for producing acrylic acid by the steps of a reaction of catalytic gas phase oxidation, absorbing the acrylic acid with an absorbent, and dehydrating the acrylic acid-containing aqueous solution, the method is characterized that the step of dehydration comprises adding and an azeotropic solvent, distilling the resultant mixture, and adjusting the acrylic acid concentration at the top of the column in the range of 0.06-0.80 wt. %, thereby preventing the bottoms of the azeotropic dehydration column from substantially containing the azeotropic solvent and water. As results, the acrylic acid is kept from forming a polymer in any of the distillation columns involved in the production, and effective utilization of acrylic acid.

Abstract: A heat exchanger for an easily polymerizing substance-containing gas provided with a shell possessed of a heat-exchanging gas inlet and a heat-exchanging gas outlet and a heat-exchanging part adapted to circulate fluid introduced from outside the shell between the gas inlet and said gas outlet, which heat exchanger is characterized by being provided with a gas distributing plate between the gas inlet and the heat-exchanging part. The heat exchanger is characterized by the gas distributing plate having a cross-sectional area in the range of 1.0-10.0 times the cross-section of the gas inlet. When an easily polymerizing substance-containing gas contacts a structure, the gas is condensed on the contact surface of the structure and suffered to generate a polymer.

Abstract: According to the present invention, a tank for storing an easily polymerizable compound, the tank fitted with a liquid inlet pipe 3, a liquid draw-off pipe 4 and a liquid recirculating pipe 5, is characterized in that, assuming terminal ends of the individual pipes 3-5 are located at the same height, the apex angle formed by a line joining the central points of the end openings of the pipe 3 and the pipe 4 at the central point of a horizontal cross section of the tank, or the apex angle formed by a line joining the central points of the pipe 5 and the pipe 4 at the central point of the horizontal cross section of the tank, is equal to or larger than 90°. A method of storing an easily polymerizable compound of the invention utilizes the aforementioned tank for storing the polymerizable compound.

Abstract: It intends to prevent the reduction in quantity with time of an N-oxyl compound in vinyl compounds. The quantity reduction of the N-oxyl compound is suppressed by causing an N-oxyl compound, N-hydroxy-2,2,6,6-tetramethylpiperidine compound and a 2,2,6,6-tetramethylpiperidine compound to co-exist in vinyl compounds.

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 to produce (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 %.