Abstract: A method and apparatus for determining heat transfer effectiveness comprises measuring coolant flow rate and input temperature for coolant to the reactor, utilizing temperature values for reactant and effluent temperatures in a relationship to obtain a value for the log means temperature difference across the reactor and calculating the actual heat transfer coefficient for heat transfer surfaces of the reactor as a function of the log mean temperature difference, the heat transfer area, the coolant flow rate and additional constant factors which are characteristics of the coolant itself.

Abstract: A display system for displaying select dynamic process data of plant operations to an operator providing a display of only dynamic data having a predetermined difference between current and stored values.

Abstract: A system for processing and selectively transmitting process signals to a computer and/or a display device is disclosed. The system utilizes a binary full adder (38) to add the incoming signal, in inverted form, to the previously transmitted signal to obtain the difference therebetween. A binary comparator (52) compares the difference with a predetermined value, established by thumbwheel switches (46), and if the difference exceeds the predetermined level, causes the actuation of a flip-flop (54) and a bistable latch (32) permitting the incoming signal to be transmitted to a computer and/or a display device.

Abstract: A technique, including an apparatus, for automatically regenerating a catalyst used in a process for obtaining a product in an exit stream from a raw material in a feed stream of a reactor, comprises determining the concentration of raw material in the feed and exit stream and obtaining a value for the catalyst selectively as a function of the difference between the concentrations. When a selected selectivity is reached, which is indicative of the need for the catalyst to be regenerated, regenerator equipment is activated for regenerating the catalyst in the reactor. To continue the process, the feed stream is transferred to an auxiliary reactor during regeneration of the primary reactor, which contains regenerated or fresh catalyst.

Abstract: A control apparatus for a tubular polymerization reactor having a feed line for a raw material to be polymerized, a cooling circuit for cooling the reactor with a flow of coolant and exit line for a product polymerization, comprises a quality sensor for sensing the actual quality of the product in the exit line, a quality controller for receiving a desired product quality set point and comparing it with the actual quality of the product to generate a desired temperature value for the reactor, temperature sensors for determining the maximum temperature of the reactor and a temperature controller for controlling the amount of coolant supplied to the reactor by the cooling circuit. The temperature controller compares the maximum temperature of the reactor with a desired temperature value therefor corresponding to the desired quantity to control the cooling circuit accordingly.

Abstract: An apparatus and method for controlling the moisture content of prilled products which are produced by air drying a spray of the liquid product, comprises a vessel for receiving a flow of air and a flow of the liquid product (10), a supply line for supplying air to the vessel (14) and a supply line for supplying liquid product to the vessel (16). The product is advantageously a solution of urea. Moisture content is measured or inferred for the product flow, the input air, and the air coming out of the vessel. An air flow controller (24) is connected for controlling the flow of air (14) into the vessel (10) which controller is itself controlled by a circuit that calculates the required air input flow rate for a desired moisture concent in the prilled product.

Abstract: A technique, including an apparatus, for automatically regenerating a catalyst used in a process for obtaining a product in an exit stream from a raw material in a feed stream of a reactor, comprises determining the concentration of raw material in the feed and exit stream and obtaining a value for the catalyst selectivity as a function of the difference between the concentrations. When a selected selectivity is reached, which is indicative of the need for the catalyst to be regenerated, regenerator equipment is activated for regenerating the catalyst in the reactor. To continue the process, the feed stream is transferred to an auxiliary reactor during regeneration of the primary reactor, which contains regenerated or fresh catalyst.

Abstract: A control system for blending a rich stream with a diluting stream to obtain a blended stream comprises obtaining values for specific gravities of the rich and diluted streams, a ratio of densities of primary and secondary components in the rich stream and value corresponding to the concentration of primary component in the rich and the blended streams. Additional elements are utilized to obtain actual volumetric flow rates for the rich stream as well as the specific gravity of water in the rich stream and the diluting stream. An algorithm is utilized to manipulate the foregoing values and obtain a desired value for the diluting stream volumetric flow rate and control the flow rate accordingly.

Abstract: A temperature control system controls the temperature of an olefin oxidation reactor by measuring various parameters in the reactor and in flow lines to and from the reactor, and using these parameters with known quantities for specific heat of the feed and effluent and heats of vaporization and reaction, to calculate a coolant flow rate set point. Parameters relating to the heat balance with regard to a desired olefin oxide product and undesired carbon dioxide products are utilized for correct control. Equipment is also provided for ascertaining the state of a catalyst used in the reaction. Circuit components are provided for obtaining changes in flow rates, temperatures and concentrations to calculate a change in coolant flow rate as well as the steady state fluent flow rate quantity to improve the system response to start up, shut down and transient conditions.

Abstract: A temperature control system controls the temperature of an olefin oxidation reactor by measuring various parameters in the reactor and in flow lines to and from the reactor, and using these parameters with known quantities for specific heat of the feed and effluent and heats of vaporization and reaction, to calculate a coolant flow rate set point. Parameters relating to the heat balance with regard to a desired olefin oxide product and undesired carbon dioxide products are utilized for correct control. Equipment is also provided for ascertaining the state of a catalyst used in the reaction.

Abstract: A surge control system is disclosed for centrifugal compressors which utilizes an algorithm to calculate a desired orifice differential pressure and compare the calculated result with an actual differential pressure. A controller is provided for operating a blow-off valve to bring the actual differential pressure to the calculated differential pressure.

Abstract: An arrangement is disclosed for temperature sensors in an exothermic chemical reactor which comprises a first plurality of temperature sensors distributed at equally spaced locations along the longitudinal axis of the reactor and a second plurality of sensors distributed on a cross-sectional plane at each location. The cross-sectional geometry of the reactor at each location has a plurality of equitempered zones which are symmetrical about the longitudinal axis. The second plurality of temperature sensors is arranged so that at least one temperature sensor is provided in each equitempered zone and some of the sensors are equispaced along a radial line. In this manner, a minimum of temperature sensors is required for establishing full longitudinal and radial temperature profiles for the reactor.

Abstract: The invention relates to dyestuff preparations comprising water, a water-insoluble or sparingly water-soluble dye, a dispersant, a humectant, and optionally further additives, wherein said humectant is a compound of the formula I ##STR1## wherein R is a C.sub.1 -C.sub.16 alkyl group which is unsubstituted or substituted by OH, CN, halogen or --N(C.sub.1 -C.sub.4 alkyl).sub.2, and R' is hydrogen or the --CH.sub.2 --CHOH--CH.sub.2 OH group.These preparations are suitable for use in aqueous or aqueous-organic dye liquors or printing inks or also for obtaining printing pastes. After partial or complete dehydration they are also very readily redispersible.

Abstract: It is possible by heating at temperatures of between 65.degree. and 200.degree. C. to convert the known .alpha.-modification of the azo dye of the formula ##STR1## which is unstable to dyeing, completely into the .beta.-modification which is stable to dyeing. The modification transformation can be performed either with the solid dye or with a suspension thereof in an organic, preferably aromatic, solvent.The novel dye modification is stable in dispersion under dyeing conditions, and shows no tendency to flocculate.

Abstract: The invention relates to the production of washing powders of stabilized or enhanced appearance which contain a fluorescent whitening agent of the formula ##STR1## or of the formula ##STR2## wherein R.sub.1 is hydrogen or chlorine, and M is hydrogen, an alkali metal or ammonium ion. The stabilizing or enhancement of the appearance is effected by first dissolving or dispersing the fluorescent whitening agent in a mixture of water and a polyvinyl alcohol or polyvinyl pyrrolidone which is soluble or is able to swell in water, adding this solution or dispersion to the washing powder slurry and drying the slurry. The solution or dispersion can also be subsequently sprayed onto the dried residual washing powder. The appearance can be further enhanced by employing a polyethylene glycol, a surfactant containing ethyleneoxy and/or propyleneoxy groups, and/or a cellulose ether, in addition to the polymer in the solution or dispersion.

Abstract: The invention relates to the production of washing powders of stabilized or enhanced appearance which contain a fluorescent whitening agent of the formula ##STR1## wherein X.sub.1 is hydrogen, chlorine, bromine, alkyl or alkoxy, X.sub.2 is hydrogen or alkyl and M is hydrogen, an alkali metal or ammonium ion. The stabilizing or enhancement of the appearance is effected by first dissolving or dispersing the fluorescent whitening agent in a mixture of water and a polyvinyl alcohol or polyvinyl pyrrolidone which is soluble or is able to swell in water, adding this solution or dispersion to the washing powder slurry and drying the slurry. The solution or dispersion can also be subsequently sprayed onto the dried residual washing powder. The appearance can be further enhanced by employing a polyethylene glycol, a surfactant containing ethyleneoxy and/or propyleneoxy groups, and/or a cellulose ether, in addition to the polymer in the solution or dispersion.

Abstract: Solid dye preparation containing at least one water-soluble dye, a lactam of the formula ##STR1## wherein x represents the numbers 3 to 6, and optionally further additives.