Description: This work is devoted to the study of the transition to gas accounting for its energy value. With the existing system of accounting and payment for gas in Ukraine, consumers, using the same number of cubic meters, receive a different calorific value. The article analyzes the most common methods for determining the heat of combustion of natural gas. To calculate the heat of combustion using direct and indirect methods. The most common is a calculation method based on chromatographic analysis of the composition of natural gas. The essence of the chromatographic method consists in the separation of a mixture of gases into individual gas components with their subsequent identification. Chromatographs are mainly laboratory facilities that are used at gas facilities to periodically monitor the quality of natural gas and ensure that its indicators comply with applicable regulations and standards. This method of determining the calorific value of natural gas is possible only with expensive equipment and at large gas metering points. Direct is the calorimetric method for determining the heat of combustion of natural gas, which is implemented using a gas water calorimeter of continuous action, based on direct measurement of the thermal energy of the gas, which is released as a result of its combustion. Taking into account the influence of the composition of natural gas on its thermophysical properties, the possibility of using methods based on the process of heat transfer in gases has been considered. Thermocatalytic and thermoconduction methods for analyzing gas composition are considered. A justification of the relevance and feasibility of using a thermocatalytic sensor as a sensitive element for the device for monitoring the heat of combustion of natural gas has been carried out. The advantages of the sensors based on thermal catalytic and thermal conductivity methods are simplicity of design, high speed. Therefore, an urgent task is to improve the existing methods and means of monitoring the energy value of natural gas and the creation of an express gas quality control device at the consumer, which will make gas metering more objective when used and in setting prices and tariffs.
Keywords: natural gas, gas quality, heat of combustion, thermocatalytic method, thermoconductometric method
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