A distillation column system and a plant are for production of oxygen by cryogenic fractionation of air. The distillation column system has a high-pressure column and a low-pressure column, a main condenser, and an argon column with an argon column top condenser. The low-pressure column comprises an upper mass transfer region, a lower mass transfer region and a middle mass transfer region. The argon column top condenser is arranged within the low-pressure column between the upper and middle mass transfer regions and is configured as a forced-flow evaporator.

Distillation column system and plant for production of oxygen by cryogenic fractionation of air

The hydrodynamics in an unbaffled stirred vessel were simulated in order to highlight the effect of gravity on pressure and velocity distributions. Two fluids with different viscosity were studied for the laminar and turbulent flow regimes, respectively. The simulation results were compared with experimental data from the literature. Results indicate that for the higher-viscosity fluid, gravity only affects static pressure and that the effects of gravity on velocity and dynamic pressure are negligible. For the lower-viscosity fluid, however, gravity imposes a pronounced impact on static pressure, dynamic pressure, velocity, and turbulent kinetic energy. These findings indicate that careful consideration is necessary for the role that gravity plays in the study of free-surface hydrodynamics in unbaffled stirred vessels.

Effect of Gravity on the Hydrodynamics in an Unbaffled Stirred Vessel

The invention provides a tube type up-down circulating heating methyl ester distillation system which comprises a heating evaporator (1), a bleaching tower (2), a condenser (5), a circulating pump (8), a storage tank I (6) and a storage tank II (7), wherein coarse methyl ester is added to the heating evaporator (1) to be decomposed, and then flows to the bleaching tower (2), the gas goes upwards to be bleached and then enters the condenser (5) for condensation, the obtained liquid methyl oleate is stored in the storage tank I (6), the material which is not completely decomposed flows to a tower bottom heating pipe (3) for further decomposition, and then is pumped into the heating evaporator (1) by the circulating pump (8), and after circulation, methyl oleate is finally obtained. Compared with a traditional scraper film evaporator and a traditional condenser, the tube type up-down circulating heating methyl ester distillation system has the advantage that the yield of methyl ester distillation equipment is greatly increased.

Tube type up-down circulating heating methyl ester distillation system and processing technology thereof

The invention relates to the technical field of extraction, separation and deep processing of grease, and provides a device and method for producing octacosanol with a specific fingerprint spectrum. According to the device, a feeding tank and a receiving tank are connected with a vacuum system, continuous batch feeding and discharging are achieved under the condition that the vacuum stability of arectifying tower is guaranteed, shutdown operation is not needed, and the production efficiency is improved; the method provided by the invention adopts a high-vacuum rectification process, and comprises the following steps: firstly, putting a saponified crude alcohol into a material dissolving tank, dissolving, putting the raw material into the feeding tank, pumping the raw material into a rectification kettle by using a conveying pump, carrying out first-batch rectification under a vacuum condition, sequentially collecting fractions at each section at the tower top, and collecting kettle residues at the tower bottom; and after the first batch of crude products are rectified, feeding a next batch of crude products under the condition that the vacuum of the feeding tank is basically consistent with that of a rectifying tower. The method provided by the invention is high in separation efficiency, controllable in fingerprint spectrum of octacosanol and stable in quality, and the requirement of the required purity of octacosanol can be met only through one-time rectification process.

Device and method for producing octacosanol with specific fingerprint spectrum

The invention discloses a deep evaporating method for a phenol hydroxylated liquid detarring tower, which comprises the following steps of: (1) feeding at a lateral line liquid phase material inlet in a rectifying tower, and pumping the tower bottoms in the rectifying tower into a bottom reboiler and a double-shaft stirring reboiler by a bottom material outlet through a circulating pump; (2) after heating the materials entering from the tower into the double-shaft stirring reboiler, changing the volatile components into steam and then distilling the steam entering the rectifying tower by a lateral line gas phase material inlet through a pipeline, changing a top gas phase of the rectifying tower into condensate after heat exchange with a condenser and soft water, and extracting part of condensate from a material extracting port on a side wall of the tower top; and (3) changing the soft water in the condenser into steam after the soft water exchanges heat with the top gas phase of the rectifying tower, and then enabling the soft water to enter a steam drum through a pipe, and conveying the steam in the steam drum to other low pressure steam users when the steam pressure reaches the set pressure According to the method, the stability of the product quality and the running reliability of the devices are improved

Deep evaporating method for phenol hydroxylated liquid detarring tower

The utility model discloses a pressure controllable vertical by-product steam condenser with a steam pocket; the condenser comprises a housing, and a heat exchange pipe arranged in the housing, wherein a soft water inlet and a water vapor outlet are arranged on the housing; both the soft water outlet and the water vapor outlet are communicated with a shell side of the heat exchange pipe; a non-congealable tail gas outlet is mounted on the top housing; a place which is 1/2-3/4 length of the heat exchange pipe on a sidewall of the housing is provided with a liquid level meter; the water vapor outlet is connected with the steam pocket by a steam pipeline; the steam pocket consists of a shell with upper and lower oval seal heads; and the shell of the steam pocket is connected with an outlet pipeline with a pressure automatic adjusting valve thereon. The condenser is arranged on the top of a distillation tower directly, thereby preventing the condensed materials from blocking equipment and pipelines, saving consumption of cooling water, and production and running cost; in addition, low pressure steam, which is a byproduct of soft water evaporation, can be taken as a heating medium continuously, thus saving energy.

Pressure controllable vertical by-product steam condenser with steam pocket

Sensitivity of pressure and velocity fields to gravity

The invention discloses a method for recovering maleic anhydride from maleic anhydride distillation kettle residues. The method comprises intermittent operation and continuous operation, wherein the intermittent operation comprises the following steps that maleic anhydride distillation kettle residues are added from a feeding opening of a double-shaft stirring reboiler, the kettle temperature of the double-shaft stirring reboiler is controlled to be 140 DEG C to 200 DEG C through controlling the heat conducting oil flow rate, the operation pressure of the double-shaft stirring reboiler and a distillation tower is controlled to be 10 to 50 KPa, the maleic anhydride distillation kettle residues are heated to be 150 to 180 DEG C, steam enters the distillation tower and is condensed by a condenser, one part of steam flows back to the distillation tower and is distributed to a lower mass transfer unit by a liquid distributor, and one part of steam enters a collecting device by a production pipeline until no gas phase is produced. The method has the advantages that the residue discharge quantity can be reduced by more than 50 percent.

Mingming Xia

Papers

Deep evaporating method for phenol hydroxylated liquid detarring tower

Pressure controllable vertical by-product steam condenser with steam pocket

Sensitivity of pressure and velocity fields to gravity

Method for recovering maleic anhydride from maleic anhydride distillation kettle residues

Torsion-induced failure of a reinforced thermoplastic pipe used in a gas lift system