SU874087A1 - Heat-mass exchange apparatus - Google Patents

Description

(54) HEAT AND MASS MEDIA

The invention relates to gas processing, petrochemical and chemical industries and can be used in mass and heat transfer processes on a liquid - gas (vapor) system.

A heat and mass transfer is known, in which the liquid is dispersed by nozzles using the energy of the flj fluid itself.

A disadvantage of the known apparatus is that the liquid is dispersed only once, therefore it is not possible to repeatedly contact with the gas (vapor) stream.

A mass transfer apparatus is also known in which the dispersion of a liquid into a gas stream is carried out by elements driven by the reaction of jets of this liquid flowing into the volume of the device 2 | .;

The disadvantage of this apparatus is that only a fraction of the liquid entering the apparatus participates in repeated contact with the gas. For example, the fluid entering the first, along the gas flow, contact stage, is in contact with the gas once, the fluid entering the second step — twice, and the third — three times as much. This creates different conditions for the process in the volume of the apparatus, which reduces its intensity.

Known heat and mass transfer apparatus,

10 comprising contact elements, in which the contact surfaces of the phases between the liquid and the gas are caused by liquid spraying devices rotating from the energy of the gas stream.

15

In a known apparatus, a part of the energy of a gas stream moving progressively in the apparatus is converted into rotation; body movement of rotary devices. The devices, rotating, capture the liquid and spray it in a moving gas stream, simultaneously creating conditions for turbulent diffusion. This apparatus allows the process of mass transfer and heat exchange by repeated dispersion of liquid without the presence of shafts and special 3 J drives. The disadvantage of this apparatus is that the process with it can be carried out only at large ratios of the contacting mass of gas to the mass of liquid. At high specific flow rates of the liquid, the phase contact surface is not developed. In the processing and purification of natural gas, especially sour gas, a large specific consumption of absorbent is required. Typically, these processes occur at pressures of the order of kg / cm. Let us assume that the process takes place at a pressure of P 50 kg / cm and at an absorbent flow rate of 3 liters per 1 reduced to normal conditions., J In one m of gas found in the apparatus at a pressure of the process, V 50 is reduced to normal conditions. this volume of gas is supplied by an L 3 V 3 × L absorbent. Density of liquid kg / l, 8 kg / nm, we find that 1 kg of absorbent is consumed in the apparatus during dispensing process. Consequently, jipn 1 m of gas (mass 50 0, kg) is consumed by its energy with the help of rotary devices rotated by him, he must create a developed contact surface by spraying L 15O kg of liquid, which is difficult to accomplish. This disadvantage is an obstacle for use in the Regeneration Process of a liquid absorber on plants with a closed cycle (with the return of the regenerated liquid into the cycle), since the regeneration of the absorber absorbs most of the liquid phase and the gas (vapor) phase is represented by only a part absorbed by the absorbent gas. The mass of the absorbed gas is incomparably small compared to the mass of the liquid fed into the desorber and its energy is not enough for the device to rotate. Also known is an apparatus for carrying out a process of mass and heat transfer, in which the surface of phase contact between liquid and gas (jtiapOM) is provided by dispersing the liquid phase by mechanical action devices. For carrying out the process in this apparatus, contact devices make a mechanical effect on the contacting flows, expressed, for example, in the form of liquid splashing, creating 874 urban flows and pulsating and centrifugal forces, and this increases the mass and heat exchange process f4 J. that it requires the installation of special drives and shafts with stringent requirements for the accuracy of their manufacture, installation, sealing and operation. Another disadvantage is the unidirectionality of the mixing phases, associated with the direction of shaft rotation. The purpose of the invention is to reduce energy consumption. To achieve this goal in the apparatus, including a housing with devices for mechanical action on the contacting streams, the latter are equipped with fluid drives and their connection with pipeline. It is advisable to supply the pipeline with a flow control fluid. FIG. 1 shows the installation with the device, connected by pipeline and having a different pressure; in fig. 2 is a diagram of the absorption unit using the energy obtained by the liquid flow from the pump. The apparatus comprises an absorber body 1 and a desorber 3. Inside the absorber 2 are liquid drives 4 connected by pipe 5, one end of which is below the level of liquid maintained in the apparatus, and the other end connected to fitting b in the upper part of the apparatus. The absorber has a grindline 7 connected to its lower part. Inside the desorber 3 there is a pipeline 8 for the passage of the saturated absorbent entering the regeneration. One end of the pipeline 8 is in the free volume of the apparatus, and the other is connected to the nozzle of the entrance of the absorbent. Desorber has an overflow line 9. Each apparatus contains a mechanical action device 10, the role of a contact device. The absorber and desorber can be equipped with a pump 11 for supplying fresh absorbent material to the absorber and a pump 12 for feeding regeneration into the desorber saturated absorbent. Liquid drives can be known devices that convert the energy of a moving stream into rotation of the elements of these devices, such as limestone turbines or impellers, installed B pipelines, the rotating axes of which are located outside the pipeline in the zone of phase contact.

Mechanical action devices are installed on the axes of the liquid drives, which can be of any known design and their design is selected depending on the desired amount of the dispersed liquid, the quality of the dispersion, or the adopted mechanism of influence on the contacting streams.

In the apparatus, there may be one or several pipelines, the expansion of which is acceptable depending on the desired direction of action of the devices.

Devices can be filled with guri;

An indispensable condition for the process in the apparatus is the presence of a pressure difference on the ends of the channel, it is necessary for the liquid flow moving through the pipeline to have sufficient energy to create an effective mechanical effect on the contacted soTOioi using liquid drives located in the pipelines and mechanical action devices.

The device works as follows.

Natural gas containing sulfur and acid components is fed to the lower part of the absorber and it moves from the bottom up.

A liquid absorber, such as an aqueous solution of monoethanolamine, is fed to the upper part of the absorber and, moving down, it passes through all the stages of contact, equipped with mechanical action devices 1O. After contacting with the gas on the steps of the contact, the liquid absorb / w collects in the lower part of the apparatus, from where, due to the existing difference between the pressures in the absorber and desorber, it enters the pipeline through its end and moves along this pipeline.

When diving through a pipeline, the liquid flow with its energy causes the blades of the wheels or the turbine of the liquid drives to rotate. The rotational energy is transmitted by means of their axes to mechanical impact devices that convert this energy into the energy of mechanical impacts on the contacting streams.

The flow that has passed through the pipeline, is removed from the absorber 2 and, preheated, enters the desorber 3.

The operation of the desorber 3 is similar to the work of the absorber 2. In the desorber 3, the liquid flow passes through the pipeline and causes the mechanical impact devices attached to the axes of these actuators to rotate using liquid drives.

The exit from the end of the pipeline, the fluid flow moves down and passes through the contact stages.

Contact devices, depending on the type adopted, produce mechanical effects of different nature and degree of intensification of the process. These effects can manifest themselves in the form of dispersing a fluid, mixing it, creating vortices and pulsations.

The degree of mechanical action of the devices 10 in the apparatus of the above schemes depends on the amount of fluid passing through the channel and its velocity. To regulate the intensive work of mechanical devices on the contacting streams in the absorber, part of the liquid is withdrawn from the apparatus, mine the pipeline using the overflow line 7. For these purposes, the overflow line 9 is used in the desorber. When leaving the apparatus through the overflow lines

7 or 9, a smaller amount of liquid passes through the pipelines, therefore, the speed of the liquid flow in the pipelines decreases, and the speed of rotation of the contact devices falls accordingly. Thus, the regulation of the intensity of the impact of the contact devices is carried out by regulating the flow of the liquid flowing through the overflow lines.

In technological installations of oil and chemical industry, the difference between the pressure of the apparatus is not sufficient to create the necessary mechanical effects on the contacting streams, the option of using the energy of the fluid it received from the pumps can be applied (Fig. 2).

In this case, the HQCOCOM 11 liquid is delivered through a pipeline to the top of the absorber and with its energy, using liquid drives, drives contact devices. The output from the pipeline, the liquid moves downward, interacting with the rising gas flow at the contact stages.

Energy is used to drive the contact devices of the desorber, which is connected by a pump 12 to the flow of fluid in the channel 13.

Claims (3)

The operation of the contact devices is regulated by entering part of the liquid into the apparatus, by passing pipelines, along flow lines: in the absorber, via line 14, in the desorber through line 15 ,. Invention Formula 1. Heat and mass transfer apparatus, comprising a housing with devices of mechanical flow located therein on contacting streams, characterized in that, in order to reduce energy costs, the devices of mechanical action are provided with liquid drives and connecting them, a pipeline. JKudKuu on gA otitel FIG. one 74087. 8 2. The apparatus according to claim 1, wherein in order to expand the load range of the fluid and the ability to control the intensity of the mechanical effect 5, the pipeline is equipped with a fluid flow regulator. Sources of information taken into account in the examination 1. Ramm V.I. Absorption of gases, to M., 1976, pp. 531-536, 2. USSR author's certificate number 565873, cl. O1D 3/30, 1977. 3. USSR author's certificate NO 497О25, cl. B 01 T) 3/30, 1975. 154. USSR author's certificate No. 386640, cl. B 01 B 3/30, 1972,; Kidkya absorber rHt eleven ii “§ / -ABOUT