405results about How to "Reduce backmixing" patented technology

Biological nutrient removal (BNR) in municipal wastewater treatment to remove carbonaceous substrates, nutrients and phosphorus, has recently become increasingly popular worldwide due to increasingly stringent regulations. Biological fluidized bed (BFB) technology, which could be potentially used for BNR processes, can provide some advantages such as high efficiency and compact structure. This present invention incorporates the fixed-film biological fluidized bed technology with the biological nutrient removal in a liquid-solid circulating fluidized bed, which has achieved the simultaneous elimination of organic carbon, nitrogen and phosphorus, in a very efficient manner and with very compact space requirements. The BNR-LSCFB has two fluidized beds, running as anoxic/anaerobic and aerobic processes to accomplish simultaneous nitrification and denitrification and to remove carbonaceous substrates, nutrients and phosphorus, with continuous liquid and solids recirculation through the anoxic/anaerobic bed and the aerobic bed. The new BNR-LSCFB system is not only an excellent alternative for conventional activated sludge type BNR technologies but is also capable of processing much higher loadings and suitable for industrial applications.

A reactor comprises a reaction zone, optionally containing a catalyst bed, and heat exchange means inoperative contact with the reaction zone, e.g. embedded in a catalyst bed, and arranged so as to received reactants for heat exchange purposes, wherein the heat exchange means is formed from a plurality of superposed metal plates wherein fluid flow channels have been formed, according t a pre-determined pattern, the channel-bearing plates being aligned during superposition to define discrete heat exchange pathways respectively for reactant and working fluids, and the said plates are diffusion bonded together.

The invention belongs to a device for solid-liquid separation/classification and non-homogeneous separation, specifically a hydraulic cyclone with improved structure of central post and overflow pipe. The device comprises a feed pipe, a cylindrical section, a coniform section, an overflow pipe and a hollow tubular central post with partial-spiral fins and spiral flow deflectors and provided outside the overflow pipe. The central post is a hollow tube provided thereon with a plurality of holes. The spiral flow deflectors are provided on the outer surface of the central post. The spiral fins are provided on the overflow pipe from the bottom of the overflow pipe to a height below the bottom of an inlet pipe. Compared with the prior art, the separation efficiency of the hydraulic cyclone is increased by 5-10% and the energy consumption is reduced by 20%. The hydraulic cyclone has high stability and reliability in separation efficiency and is suitable for solid-liquid separation in ore dressing, dredging, chemical and petroleum industries.

The invention discloses a fluidized bed reactor used for light olefin cracking and Methanol To Olefin (MTO), which comprises a reactor and a pre-riser; the reactor comprises a dense phase fluidized bed reactor and a dilute phase conveying reactor which are positioned at same axis, the pre-riser and the dilute phase conveying reactor are respectively positioned at upper part and lower part of the dense phase fluidized bed reactor; diameter of the pre-riser is smaller than diameter of the dense phase fluidized bed reactor, the upper part of the pre-riser extends into the dense phase fluidized bed reactor; an upper end port of the pre-riser in the dense phase fluidized bed reactor is sealed, and a perforate is provided on the tube wall of the pre-riser in the dense phase fluidized bed reactor; or the perforate is provided on the upper end of the pre-riser in the dense phase fluidized bed reactor, and a baffle plate is arranged over the perforate. The reactor is capable of increasing gas-solid contact efficiency, the backmixing degree of oil gas and a catalyst is less, and conversion rate of one way of the light olefin cracking and Methanol To Olefin (MTO) reactions can be greatly improved, and the target product micromolecule olefin selectivity can be greatly improved.

The tooth edge float valve includes tabulated valve cover, liquid facing valve leg on one end of the valve cover and in the upstream position, liquid backing valve leg on the other end of the valve cover and in the downstream position, and valve feed fixed separately to the lower ends of the liquid facing valve leg and the liquid backing valve leg. The valve cover has downward bending toothed structures in the sides and the downward bending toothed structures can reduce the bubble diameter, raise the stability of the foam layer and avoid the direct spray of gas and liquid. In addition, the valve cover is provided with wedged slot to avoid the formation of gas flow eddy below the float valve, decrease liquid back mixing and lower the gas resistance of the float valve; and the liquid backing valve leg is provided with liquid guide hole for gas to drive liquid towards the outlet dam so as to reduce the liquid surface fall and decrease liquid back mixing.

The liquid-liquid-liquid three-phase continuous lifting and stirring extractor includes one horizontal reactor with two stuffing-holding isolating board cases in its two ends; one upper shaft and onelower shaft penetrating the reactor side walls and installed parallelly to the isolating board cases; upper baffle and lower baffle with horizontal arc lift tank in between; light phase outlet, middle phase inlet and heavy phase outlet successively arranged on one side wall of the reactor; light phase inlet, middle phase outlet and heavy phase inlet successively arranged on the opposite side wallof the reactor; and motor driven wheels installed in the ends of the two shafts. With simple structure, low power consumption, flexible operation, no emulsification and less back mixing, the presentinvention is suitable for separating and purifying high-value biochemical product from relevant fermented liquid.

The invention provides an extraction device and method. A mixed settler extractor comprises a mixing chamber, an organic liquid film generator, a gas-liquid separation device and a liquid-liquid coalescence separation device. The mixing chamber is provided with a heavy phase input port and a first heavy phase discharge port. The organic liquid film generator is connected with the mixing chamber and provided with a light phase input port and a gas inlet. The gas-liquid separation device is connected with the mixing chamber. The liquid-liquid coalescence separation device is connected with the gas-liquid separation device and provided with a liquid inlet, a first light phase discharge port and a second heavy phase discharge port. The extraction device can be provided with no clarifying chamber, the integrated structure of the mixing chamber and the clarifying chamber is well achieved, the problem of heavy phase liquid distribution uniformity of a mixing chamber and the problem about light phase, heavy phase and gas phase separation of the mixing chamber are solved, the occupied area is small, energy consumption is low, a high-flow water solution containing a to-be-separated target object can be treated, and back-mixing of a high-position extraction tower can be relieved.

A gas-liquid contact unit for the mass-transfer separation tower in order to increase the efficiency of tower plate is composed of a cylindrical or truncated conic spray hood with uniformly distributed spray holes, a circular top plate with uniformly distributed guide holes and installed to top edge of said spray hood with a window between them, and 3-4 supporting legs for installing it at the flow-up air hole on tower plate.

The present invention discloses one spouted fluidized bed pelletizer with several spouting units. The pelletizer consists of mainly casing, spouted fluidized bed pelletizer with several spouting units comprising vertical partition boards inside the casing. Each spouting unit consists of gas distributing board, self-cleaning pressure jet or self-cleaning double-fluid jet, and guide tube over the jet. The guide tube separates the spouting unit into spouting area and annular area in the area ratio of 0.2-0.5. The ventilating hole in the annular area is inclined hole and that in the spouting area is vertical hole. The present invention has simple structure, less back mixing of the particles and high product homogeneity. The self-cleaning jet without choking and the inclined holes in favor of exhaust of large particles can ensure the continuous production.

The invention provides a method for synthesizing 2-methyl-5-nitroimidazole-1-ethanol, which comprises the following steps: the mixed solution of 2-methyl-5-nitroimidazole, formic acid and sulfuric acid is prepared according to the mole ratio of 1:0.5-0.7:1.2-1.7; ethylene oxide and concentrated sulfuric acid with the mole ratio of 1:0.08-0.3 are alternately added into the mixed solution for 3-4 times; the reaction temperature is 72-108 DEG C, the reaction time is 2.5-5 hours, and after reaction, sodium hydroxide is added to regulate the PH value of the solution to 9.5-10.5, and a finished product is precipitated through crystallization; and a 2-methyl-5-nitroimidazole-1-ethanol finished product is obtained through purification. In the method for synthesizing 2-methyl-5-nitroimidazole-1-ethanol provided by the invention, the mixed solution of formic acid and sulfuric acid is used as a solvent, the conversion rate and the yield are obviously improved, formic acid and sodium hydroxide consumption is less, and the production cost is low.

The invention belongs to the field of urea preparation, and particularly relates to an energy-saving urea production system and a production process thereof. The system comprises a CO2 compressor, an ammonium carbamate pump, a liquid ammonia pump and a urea synthesizer. The system is characterized in that the CO2 compressor is connected with the ammonium carbamate pump and the liquid ammonia pump, the liquid ammonia pump is connected with the urea synthesizer, a falling-film countercurrent medium-pressure decomposing tower and a heater, an ammonium carbamate condenser, an ammonium carbamate separator, a three-stage medium-pressure absorption tower and an evaporative ammonia refrigeration recoverer, a liquid ammonia buffer tank, an inert gas scrubber, a tail-gas ammonia cleaning fine purifier, a low-pressure decomposing tower and a heater, a dimethyl liquid preheater, a horizontal low-pressure absorber, a falling film type pre-evaporator, a one-stage evaporator and a one-stage evaporative condenser, a two-stage evaporator and a two-stage evaporative condenser, and a process wastewater desorption and hydrolysis tower are sequentially connected behind the urea synthesizer in sequence. The energy-saving urea production system has the advantages of low investment, low energy consumption, simple operation, high elasticity and the like, thereby the process technology has considerable economic benefit and social benefit.

The invention provides a separation method of diolefin in carbon-5 aiming at the problem of high content of cyclopentadiene in isoprene when the diolefin in carbon-5 is separated by utilizing the post-heating dimerization method. The method comprises the following steps of: carrying out thermal dimerization reaction for two times, carrying out heavy removal for two times and removing the cyclopentadiene in the carbon-5 by using a special thermal dipolymer reactor. The content of the cyclopentadiene in the isoprene prepared by adopting the method is below 1 percent (weight), and meanwhile, thecontent of cyclopentadiene in produced piperylene is less than 1 percent (weight); and the content of an isoprene autopolymer or an isoprene copolymer in dicyclopentadiene can reach the level of a post-heating dimerization carbon-5 separation technology. The invention also discloses equipment for implementing the separation method at the same time.

A liquid film impact type spray reactor for the fast mixing and reaction between two kinds of liquid is composed of material feeding inlets, the coaxially arranged central axle, internal ring tube and middle ring tube, and a mixing head whose lower end is connected with that of central axle.

The invention relates to the technical field of reaction devices for petrochemical engineering, fine chemistry, pharmacy, plastic, synthetic rubber, coating, food processing and the like, in particular to an intelligent industrialized micro-channel flow reactor which greatly improves safety and environment protection performance, greatly saves energy and greatly improves production efficiency. The intelligent industrialized micro-channel flow reactor comprises a shell, a raw material inlet, a product outlet, an end socket and a reaction pipe, and is characterized in that a three-dimensional micro-channel assembly is closely inserted in the reaction pipe, and a plurality of continuous-penetrating micro-channels in the scale of microns or millimeters are formed between the outer surface of the three-dimensional micro-channel assembly and the inner wall face of the reaction pipe. The mass transfer resistance between reaction raw materials is greatly reduced, reaction heat can be rapidly conducted in time, reaction time is shortened, back-mixing and side reaction are reduced, solvent consumption is lowered or eliminated, safety and reliability are high, energy conservation and emission reduction can be greatly achieved, yield is increased, and production efficiency is improved.

The invention discloses a method of preparing propylene epoxide. The method comprises the following steps: adding raw materials propylene, hydrogen peroxide, a solvent methanol and a titanium silicalite molecular sieve catalyst into a reaction kettle in proportion, regulating the temperature and the pressure in the reaction kettle, and establishing a cycle; continuously adding the reaction raw materials and the solvent into a pipeline reactor to react from the outside of the reaction kettle, mixing the reaction raw materials and the solvent in a static mixer and then feeding the mixed materials and the solvent into a reaction kettle to react sufficiently to obtain the propylene epoxide. On the lower part of the reaction kettle, the reaction product propylene epoxide and the catalyst are separated under a certain pressure, so that the separated propylene epoxide enters a follow-up process, and the catalyst is fed into the equipment such as the pipeline reactor by virtue of a circulating pump outside the reaction kettle to return to the reaction kettle to continuously react. In the reaction kettle, backwashing is performed once every 10-300s to guarantee the continuity of the separation of the reaction. According to the method disclosed by the invention, the raw materials sufficiently contact with the catalyst, so that the conversion ratio of the hydrogen peroxide is not lower than 96%, and the selectivity of the propylene epoxide is not lower than 95%. The reaction separating device is reasonable in structural arrangement and stable in reaction.

The present invention relates to a hole-jetting type reactor and its applications, in particular to a process for the production of isocyanates by the phosgenation of aliphatic or aromatic diamines or triamines in the gas phase using this reactor. The present invention achieves a good mixing and reacting result of the gas-phase phosgenation reaction at a high temperature by improving the mixing of reactants in the reactor to reduce the possibility of forming swirls and eliminate negative pressure produced at a local jet area, which can finally reduce back-mixing and formation of solid by-products.

The invention relates to a multi-level solid fuel drying system. The multi-level solid fuel drying system comprises a horizontal fluidized bed, a filter and a heating box, wherein the horizontal fluidized bed, the filter and the heating box are connected with one another; the horizontal fluidized bed is divided into fluidizing chambers of different sections by baffles; a heat exchanger is arranged in each fluidizing chamber; the horizontal fluidized bed takes overheat steam as fluidized gas and is used for carrying moisture, and takes multi-level saturated or nearly saturated steam with 105-300 DEG C as heating steam; moisture-containing fuel flows through the fluidizing chambers in sequence under a fluidizing state and is heated by the heat exchangers immersed in bed particles for layered drying or temperature adjustment, and meanwhile, the heating steam passing through the heat exchangers of different sections and the overheat steam passing through the fluidized bed are enabled to pass through the heating box for heat integration; and the step utilization of heat energy in a drying process is realized while the integrated heat is recovered and the overheat steam is recycled. Compared with the prior art, the multi-level solid fuel drying system provided by the invention has the advantages of returning and mixing of smaller fluidized bed drying particles and step utilization of drying heat source and the like.

Dialkyl esters of 2,5-furandicarboxylic acid are prepared from a 2,5-furandicarboxylic acid-containing starting material in a process, which includes: contacting a vaporous stream of an alkanol countercurrently with the at least partially liquid starting material having the 2,5-furandicarboxylic acid, in a reaction zone to conduct an esterification reaction to yield the dialkyl ester of 2,5-furandicarboxylic acid and water; withdrawing a reaction vapor comprising the alkanol and water from the reaction zone; and discharging a liquid phase having at least the dialkyl ester of 2,5-furandicarboxylic acid, from the bottom part of the reaction zone, to obtain the dialkyl ester of 2,5-furandicarboxylic acid.

The invention relates to a continuous production method and device for preparing propionic acid through air oxidation of propionaldehyde. The method comprises the steps that propionaldehyde enters a reactor through a liquid phase inlet in the bottom of a first-order oxidation reactor and makes contact with and is mixed with some compressed air, a majority of propionaldehyde in the raw material is converted into propionic acid through an oxidation reactor, a first-order oxidation product containing a small amount of propionaldehyde continuously enters a second-order or multi-order oxidation reactor and is continuously subjected to the oxidation reaction with the compressed air, and finally the propionic acid with the high-purity is generated. The device comprises two or more oxidation reactors connected in series, a condenser is arranged on the top of each oxidation reactor, and gas phase pipelines and backflow pipelines are arranged between the oxidation reactors for connection. A tail gas processing device is arranged behind each oxidation reactor. A gas phase pipeline is arranged between each condenser and the corresponding tail gas processing device for connection. The reaction conditions are mild, the product yield is high, the product quality is good, the propionaldehyde conversion rate is larger than 98.5%, the selectivity of the propionic acid is larger than 97.5%, and the product purity is larger than 99.5%.

A double-CFB (circulating fluidized bed) reaction-regeneration system and method to prepare arenes with synthetic gas are provided. The system herein comprises an aromatization reactor and a catalystregeneration reactor which are connected with each other through a pipeline; the aromatization reactor comprises a first catalyst filling area and a second catalyst filling area; the catalyst regeneration reactor includes a fourth catalyst filling area and a third catalyst filling area; the aromatization reactor is filled with a hydrocarbon synthetic catalyst and an aromatization catalyst; under the action of a flow of gas, the hydrocarbon synthetic catalyst stays mainly in the area below, and the aromatization catalyst stays mainly in the area above. A regeneration method is also disclosed, including: after the aromatization catalyst is inactive, allowing the aromatization catalyst to enter a low-temperature hypoxic area of the catalyst regeneration reactor and then enter a high-temperature hyperoxic area of the catalyst regeneration reactor. The system and method herein have the advantages that controlling at different temperatures is achieved and catalyst design is less difficult.