Gasification of Waste Machine Oil by the Ultra-Superheated Mixture of Steam and Carbon Dioxide

Abstract

Reported in the article is further progress in the development of the novel pulsed detonation gun (PDG) technology for the conversion of organic wastes into syngas in a two-component gasifying agent (GA) containing ultra-superheated steam and carbon dioxide obtained by pulsed detonations of a natural gas–oxygen mixture at a frequency of 1 Hz. Experimental studies were carried out on a waste converter with a 40 dm3 flow reactor and two PDGs with a total volume of 2.4 or 3.2 dm3, which is approximately a factor of 6 and 4.5 less than in previous studies, respectively. The objective of the research was to find the design and operation parameters of the waste converter that provide a minimum amount of CO2 in the gasification products. Waste machine oil was used as a feedstock. It is shown that, compared with the earlier experiments with a higher average temperature of the reactor wall and with a PDG of a much larger volume, the contents of H2, CO, CH4, and CO2 in the syngas remained virtually unchanged, whereas the efficiency of the gasification process increased significantly: the use of 1 g of natural gas made it possible to gasify up to 4 g of the feedstock. It is also shown that the determining role in the gasification process of liquid feedstock is played by the feedstock residence time in the PDG rather than in the reactor. The minimum ratio between the flow rates of the GA and liquid feedstock, the minimum ratio between the flow rates of combustible gas and liquid feedstock, as well as the actual GA consumption in the gasification process are determined experimentally.

Gasification of Liquid Hydrocarbon Waste by the Ultra-Superheated Mixture of Steam and Carbon Dioxide: A Thermodynamic Study

“…When analyzing the data in Table 1, the following observations are worth mentioning. Firstly, the WO/GA mass ratio in the experiments [37] varied from 0.75 to 1.18, which was considerably larger than the value of WO/GA = 0.45 ensuring the maximum content of H 2 in the produced syngas according to Figure 7. Secondly, the measured wall temperature of the gasifier (=823-873 K) is seen to be 150-180 K less than the calculated equilibrium temperature of the gasification products (about 1000 K), which looks reasonable as the gasifier was not thermally insulated in the experiments.…”

“…Currently, such installations for the steam gasification of organic waste, meeting specific requirements in terms of the operation temperature, the feedstock residence time, the composition of the produced syngas, etc., can be designed using computational fluid dynamics [35] and equilibrium gasification models [32,33,36]. The technology has been implemented in experimental installations and tested on a number of organic wastes, including WO [37], which is a subject of particular interest for environmentally safe utilization [38,39]. The GA generator (i.e., PDG) operates in a pulse mode, and the pulse frequency is mainly determined by the time of tube filling.…”

“…It is instructive to compare the results of the calculations in Figure 7 with experimental data for the gasification of waste machine oil with the GA obtained by the pulsed detonations of the stoichiometric natural gas-oxygen mixture [37]. Experiments in [37] were conducted with a pulsed detonation frequency of 1 Hz. The pressure in the gasifier was slightly above atmospheric pressure, i.e., P 0 ≈ 1 bar.…”

“…Table 1. Comparison of measured [37] and calculated results for the gasification of the waste machine oil by the detonation products of the stoichiometric methane-oxygen mixture. When analyzing the data in Table 1, the following observations are worth mentioning.…”

Thermo-Mechano-Chemical Processing of Printed Circuit Boards for Organic Fraction Removal

“…The TMCG method has already been successfully demonstrated for the natural gas conversion [40] and gasification of liquid/solid wastes (waste machine oil, sawdust, sunflower seed husks, etc.) [40][41][42][43]. The objective of this paper is to demonstrate the TMCG method on the gasification of waste PCBs using a new experimental setup and accompanying measurements of gaseous and solid gasification products by the chromatography-mass spectrometry (GC-MS), CHN analysis, wet laser diffraction method, and X-ray fluorescence (XRF).…”