Abstract: A method of treating a wastewater, containing the steps of: filtering a wastewater supplied into an activated sludge tank and biologically-treated therein, in a membrane module installed outside the activated sludge tank; chemical-cleaning the membrane module with a membrane-cleaning agent while the membrane module is disconnected from the activated sludge tank with a valve; and water-flushing off the substances contained in the wastewater that react with the membrane-cleaning agent and form hazardous substances and/or operation-inhibiting substances, or the membrane-cleaning agent remaining in the membrane module with water while the membrane module and the activated sludge tank are disconnected from each other by the valve, wherein the membrane-cleaning agent is prevented from contacting the substances contained in the wastewater that react with the membrane-cleaning agent and form hazardous substances and/or operation-inhibiting substances.

Abstract: There are provided a method for analyzing an aqueous ammonium carbamate solution whereby the composition of an unreacted-gas absorber outlet liquid can be specified in real time, and a method for operating an unreacted gas absorber by use of the same.

Abstract: There is provided a radial flow reactor having a multi-pass structure in which loading and unloading of granular packing are easy and which does not impair the reaction performance. The reactor includes, in an upright tubular reactor vessel: a packing region for housing a continuous packed bed of granular packing; and an outer and an inner passages disposed outside and inside the packing region, respectively, allowing a fluid to flow in the axial direction. The reactor is configured so that the fluid can pass between the packing region and the outer passage and between the packing region and the inner passage. The reactor further includes at least one of an outer partition structure and an inner partition structure.

Abstract: An apparatus for manufacturing a polymer resin comprises a polymerization vessel, a bearing part, a protection part, a circulating cooling means, a raw material-injecting nozzle and a flow path-constituting part. The protection part forms a first flow path between the protection part and the side face of the agitation axis. The circulating cooling means includes a circulating inlet nozzle provided on a side face of the protruding part so as to be opposite to the protection part. The flow path-constituting part is provided between the bearing part and the protection part so as to cover the side face of the agitation axis, to fix the bearing part and the protection part. This flow path-constituting part forms a second flow path between the side face of the agitation axis and the flow path-constituting part and a third flow path for coupling the second flow path with the raw material-injecting nozzle.

Abstract: A reactor including a reactor vessel and heat exchange tubes provided in the reactor vessel. The reactor vessel includes a tubesheet and is configured to receive a reaction fluid. The tubesheet has a first plate member configured to contact the reaction fluid and a second plate member configured to not contact the reaction fluid. Heat exchange tubes are provided in the reactor vessel and fixed to the first plate member. The heat exchange tubes are configured to receive a heat exchange medium. At least a portion of the first plate member configured to contact the reaction fluid is made of a metal that has a high corrosion-resistance against the reaction liquid, and the second plate member is made of a metal that has a low corrosion-resistance against the reaction liquid. The second plate member is detachably fixed to a remainder of the reactor vessel.

Abstract: A supported carbon having high surface area, high pore volume containing (i) molybdenum (ii) a metal of non noble Group VIII, (iii) phosphorous, is used for hydrometallization of heavy crude oil and residue. The catalyst contains about 6 to 15 wt % molybdenum as MoO3, about 1 to 6 wt % cobalt or nickel as CoO or NiO and phosphorus as phosphorous oxide. One characteristic of the catalyst is the portion of pores having pore diameter in the range of 200 to 2000 Angstrom of 20 percent or more. The catalyst prepared by chelating agent has higher hydrodesulfurization activity assuming that more dispersed active metals are present on this catalyst. Long run activity studies show that catalyst having only molybdenum supported on activated carbon has good stability with time-on-stream and very high metal retention capacity.

Abstract: A reactor including a reactor vessel and heat exchange tubes provided in the reactor vessel. The reactor vessel includes a tubesheet and is configured to receive a reaction fluid. The tubesheet has a first plate member configured to contact the reaction fluid and a second plate member configured to not contact the reaction fluid. Heat exchange tubes are provided in the reactor vessel and fixed to the first plate member. The heat exchange tubes are configured to receive a heat exchange medium. At least a portion of the first plate member configured to contact the reaction fluid is made of a metal that has a high corrosion-resistance against the reaction liquid, and the second plate member is made of a metal that has a low corrosion-resistance against the reaction liquid. The second plate member is detachably fixed to a remainder of the reactor vessel.

Abstract: A document management device (100) comprises a document information storage unit (114) for storing document information including at least one keyword associated with a document so as to search for the document, a sectoral keyword list storage unit (122) for storing a sectoral keyword option list containing a technical keyword relating to each of sections, a common keyword list storage unit (120) for storing a common keyword option list containing a general keyword common to the sections, an authenticating unit (108) for authenticating the login by the user into a section, a presenting unit (128) for displaying the sectoral keyword option list of the section and the common keyword option list on a screen, a keyword receiving unit (130) for receiving the in keyword selected from the sectoral or common keyword option list, a searching unit (132) for searching the document information storage unit (114) by using the received keyword, and a presenting unit (128) for presenting the search result to the user.

Abstract: In a process of hydrocracking heavy oil with a catalyst in petroleum refining, asphaltene contained in heavy oil, and impurities including heavy metals such as nickel and vanadium, are efficiently removed with activated carbon, whereby the reduction in catalyst activity or formation of coke by the impurities can be prevented. The invention provides a hydrocracking catalyst comprising activated carbon extrudate as a carrier activated with steam and having a high distribution of pores having pore sizes in the range of 20 to 200 nm.

Abstract: A method for treating a formaldehyde-containing waste liquid, which is formed as a byproduct in a plant for the production of hydrocarbons or oxygen-containing compounds, containing the steps of: subjecting formaldehyde in the liquid to chemical treatment; and treating the resulting waste liquid, while being aerated, by using a membrane bioreactor that is composed of a microorganism or enzyme and a separation membrane.

Abstract: A method of treating organic matter-containing waste liquid, which is formed as a byproduct in a plant for the production of oxygen-containing compounds or liquid hydrocarbons (including liquid fuel oil and chemicals, which are produced from natural gas through a synthetic gas), having the step of: treating the waste liquid at a high temperature of 40° C. or higher, while being aerated, by using a membrane bioreactor (2) that is equipped with a separation membrane (7b).

Abstract: In a granulating process for preparing granular urea from an aqueous urea solution using a fluidized bed method or a fluidized, spouted bed method, an aqueous urea solution having a urea concentration of 94-98.5 wt % is used and the operational temperature of the fluidized bed is controlled in a range of 110-120° C. to accelerate the drying of a granulated product to thereby give a granular urea product having a moisture content of 0.3 wt % or less.

Abstract: It is intended to enable an apparatus for synthesizing urea and a method for revamping the same to place a heavy condenser at a relatively low position and to circumvent problems associated with letting a process fluid flow within a tube in the condenser. The present invention provides an apparatus for synthesizing urea including: a synthesis reactor for reacting NH3 with CO2 to obtain a urea synthesis solution containing urea, unreacted NH3 and CO2, and water; a stripper for stripping the urea synthesis solution with use of at least a part of raw material CO2 to separate a gas containing the unreacted NH3 and CO2; a vertical submerged condenser having a shell and tube structure for condensing the gas in an absorbing medium on the shell side while cooling the gas with a cooling medium passing through the tube side; and recycling means for recycling a liquid obtained from this condenser to the synthesis reactor, wherein this condenser is placed below the synthesis reactor.

Abstract: It is intended to enable more smooth operation in an apparatus for synthesizing urea by circumventing the downward flow of a urea synthesis solution which is a gas-liquid two-phase flow and stabilizing the flow of the urea synthesis solution still remaining the gas-liquid two-phase flow and to reduce energy loss by giving smaller flow resistance.

Abstract: A device to reform a raw material gas into a synthesis gas rich in hydrogen and carbon monoxide is disclosed. The device includes a vessel, a floating head, a plurality of reaction tubes, inlets and outlets for raw material and heating gases, and a cooled fixed tube plate.

Abstract: In a process and an apparatus for synthesizing urea which synthesize urea from ammonia and carbon dioxide, the operating condition can be grasped easily and with good accuracy. A process for synthesizing urea which includes: a reaction step of obtaining a urea synthesis solution which contains urea, unreacted ammonia, unreacted carbon dioxide and water by causing ammonia and carbon dioxide to react with each other; a stripping step of separating a gas mixture containing the unreacted ammonia and the unreacted carbon dioxide by stripping the urea synthesis solution by using at least a portion of raw material carbon dioxide; a condensing step of obtaining a condensed liquid by condensing the gas mixture in an absorbing medium while cooling the gas mixture; a recycling step of recycling the condensed liquid to the reaction step; and a step of measuring the density of the condensed liquid online. An apparatus for carrying out this process is provided.

Abstract: A reactor including a reactor vessel and heat exchange tubes provided in the reactor vessel. The reactor vessel includes a tubesheet and is configured to receive a reaction fluid. The tubesheet has a first plate member configured to contact the reaction fluid and a second plate member configured to not contact the reaction fluid. Heat exchange tubes are provided in the reactor vessel and fixed to the first plate member. The heat exchange tubes are configured to receive a heat exchange medium. At least a portion of the first plate member configured to contact the reaction fluid is made of a metal that has a high corrosion-resistance against the reaction liquid, and the second plate member is made of a metal that has a low corrosion-resistance against the reaction liquid. The second plate member is detachably fixed to a remainder of the reactor vessel.

Abstract: An information management apparatus of the present invention including a database DB1, in which document information and keywords which have been correlated to the document information in order to search for the document information are electronically saved, a copy unit that copies the document information and the keywords from the DB1 at the same time, a keyword temporary storage unit that stores the copied document information and keywords, a keyword acceptance unit that accepts entry of the keyword selected from a list of keyword options displayed on a keyword entry screen as a keyword to be correlated to the copied document information, a notification unit that prompts entry of the keyword from the keyword option list displayed on the keyword entry screen when the document information is copied, and a registration unit that stores the keywords in the storage unit into a database DB2 in a condition where they are correlated to the document information in the storage unit, wherein the keywords in the storag

Abstract: There are provided a process for separation of hydrocarbons including the steps of: (a) a feed gas is cooled and partly condensed, and separated into a gas and a liquid; (b) the liquid obtained in step (a) is supplied to a distillation column; (c) the gas obtained in step (a) is expanded by an expander and partly condensed, and separated into a gas and a liquid; (d) the liquid obtained in step (c) is supplied to the distillation column; (e) the gas obtained in step (c) is divided into a first portion and a second portion; (f) the first portion is supplied to the distillation column; (g) the second portion is condensed by being compressed and cooled, and then depressurized and supplied as a reflux to the distillation column; and (h) a residue gas is obtained from the top part of the distillation column and a heavier fraction is obtained from the bottom part of the distillation column; and an apparatus therefor. The process and apparatus enable efficient separation of hydrocarbons.

Abstract: A duplex stainless steel for use in urea manufacturing plants, in mass %, consisting of C: 0.03% or less, Si: 0.5% or less, Mn: 2% or less, P: 0.04% or less, S: 0.003% or less, Cr: 26% or more, but less than 28%, Ni: 6-10%, Mo: 0.2-1.7%, W: more than 2%, but no more than 3%, N: more than 0.3%, but no more than 0.4%, with the balance being Fe and impurities, in which the content of Cu as an impurity is not more than 0.3%. The duplex stainless steel may also have Ca, Ce, and B content, and it is desirable that levels of Al and O (oxygen) as an impurities be no more than 0.05% and 0.01% respectively. Further, it is preferable that an increase in the Vickers hardness of the steel should not be more than 80, before and after the solution treated steel is subjected to the heat treatment of 800° C. for 30 minutes and subsequent water cooling. This duplex stainless steel possesses a high corrosion resistance.