До питання про сушіння газів на основі короткоциклової безнагрівної адсорбції

Abstract

TO THE QUESTION OF DRINKING GASES

ON THE BASIS OF SHORT-CIRCULAR NON-ADDRESSING ADSORPTION

B. Draganov, Yu. Sneshkin

Any solid has a surface, which means it is potentially an adsorbent. However, solid adsorbents with a highly developed internal surface (pore volume) are used in the technique. The development of the inner surface (volume of pores) in a solid is achieved by creating special conditions in the process of its synthesis or as a result of additional processing.

Adsorption is a process involuntary and exothermic, that is, its flow is accompanied by the release of heat.

In contrast to the physical adsorption at chemisorption, the individuality of the adsorbent and adsorbent is not preserved.

The purpose of the study is to analyze the processes of drying gases based on short-cycle heat-free adsorption.

Consider the basics of air drying on the basis of the adsorption unit. It uses a system of short-cycle and non-heating adsorption.

As a rule, silica gel is used as an adsorbent in short-cycle installations. Initially, the Seligel Gale plant was used only for the drying of natural gas, but during the operation it was established that along with moisture there is a selection of hydrocarbons in the gasoline series, and the drying plants began to rebuild in plants that combine the functions of drainage and desertification.

The selikagel is cooled with dry or wet gas. In the latter case, it is necessary to pay attention to the fact that the directions of gas flows in the cooling stages coincide.

Achievement of high and stable degree of drainage is possible only at sufficient length and continuous operation of the adsorption unit. In the period of stopping the moisture due to diffusion accumulates in the main equipment and communications, which significantly impairs the dryness of the gas after re-start. Particularly strong moisture of the apparatus is noted after periodic hydraulic tests, which are carried out with water.

Schemes of short-cycle installations are very simple. The duration of the adsorption, desorption and cooling stages is 30-60 minutes and depends on the performance of the plant on the processed gas, the mass of the adsorbent and the content of the gas in the extracted components.

Studies show that it is possible to conduct regeneration without heat supply - only by reducing the pressure and (or) purging the gas part of the purified stream.

This principle of regeneration is the basis of short-cycle non-heating adsorption plants, which are widely used primarily for drying gas.

Short-cycle installations for non-heat-absorbing adsorption are compact, which makes them easy to move. If the air is not drained, the gas of the latter can be avoided by connecting the return flow to the gas being sent for drying. The absence of heat consumption for adsorbent heating is one of the reasons that ensures high economic efficiency of installations of this type. At the same time, it must be taken into account that continuous operation of a short-cycle unit is possible only under the condition of a reliable and fast-moving flow control system.

Short-cycle non-heating installations are used not only for drying and gas cleaning, but also for the separation of two- or three-component gas mixtures.

Conclusions and perspectives. The main advantage of short-cycle adsorption is the higher productivity of the installations at comparable dimensions and the absence of auxiliary devices to heat the regenerating air.