Analysis of damage caused by siloxanes in stationary reciprocating internal combustion engines operating with landfill gas

Abstract

Failures in reciprocating internal combustion engines operating with landfill gas are not uncommon. In general, damage is located in the combustion chamber surfaces and in the ring grooves, where a layer of non-volatile combustion products is deposited. These deposits attached to the surfaces reduce heat transfer and increase inner temperature, which produces a knocking phenomena damaging the crank bearings and fusing of the piston head material. Lubrication problems also appear due to the formation of a layer of soft paste silicone deposits in the rings grooves, which increases friction losses and accelerates wear on cylinder and rings. In this paper, some typical examples of damaged engines are presented. The deposits found were analysed using Scanning Electron Microscope and Energy Dispersive X-ray Spectroscopy (SEM-EDX). Additionally, the engine oil used was also analysed by Infra-Red Spectrometry (IR) and the results were compared with known organo-compounds. A method to detect incipient failure caused by organo-compounds contained in landfill gas is introduced. Silica appears in the layers covering the combustion chamber, as well as silicone compound in the top cylinder zone, piston and ring grooves. Damage is associated with siloxanes (organo-silicon compounds) contained in the landfill gas, which decompose in the combustion chamber, generating silicic acid and formaldehyde under the high temperature conditions throughout the combustion processes. Dear EditorThank you for agreeing to review the following manuscript, we would like to thank also the reviewers for the previously received comments. We want to extend our appreciation for taking the time and effort necessary to provide such guidance.As suggested by the editor a throughout revision of the paper has been carried out and the comments of the reviewer has been 100 % included in the current version of the manuscript. All changes on the original version of the manuscript appear in red in the current version.The reviewer commented the first half of manuscript, but his recommendations have been extended to the whole manuscript. Reviewer: 1 ADDITIONAL COMMENTS TO THE AUTHOR:The new Research Highlights according the magazine rules has been uploaded. Yours sincerelyJesus Alvarez-Florez *Detailed Response to Reviewers HighlightsThe main types of damage found in ICE using landfill gas have been studied Combustion of fuel with siloxanes produces two types of residues Residues attach to combustion chamber surfaces reducing the heat transfer Residues also attach to piston ring grooves causing lubrication problems A method to prevent damage based in engine oil IR analysis is presented ABSTRACTFailures in reciprocating internal combustion engines operating with landfill gas are not uncommon. In general, damage is located in the combustion chamber surfaces and in the ring grooves, where a layer of non-volatile combustion products is deposited. These deposits attached to the surfaces reduce heat transfer and increase inner temperature, which produces a k...

Siloxane removal for biogas purification by low cost mineral adsorbent

“…Biogas is generally a mixture of 50-70 v% methane, 30-50 v% carbon dioxide, and <6 v% residual compounds such as water vapor, hydrogen sulfide, and siloxanes (Poloncarzova et al, 2011). Hydrogen sulfide and siloxanes must be removed from the biogas to increase the calorific value and avoid damage to the combustion system (Álvarez-Flórez andEgusquiza, 2015, Kapoor et al, 2020).…”

“…Removal of hydrogen sulfide can be achieved by biological treatments that are inexpensive and environmentally friendly (more extensive review on removal of hydrogen sulfide by biological treatment can be found in Khoshnevisan et al, 2017). On the other hand, the siloxanes are undesirable in a gas combustion system due to the formation of silicon dioxide (Álvarez-Flórez and Egusquiza, 2015). The silicon dioxide solid deposits damage parts of the combustion system such as pistons, cylinder heads, and valves (Matsui and Imamura, 2010) causing low efficiency and high repair costs (Ajhar et al, 2010).…”

Fluctuations of the elemental composition in the layers of mineral deposits formed on the elements of biogas engines

“…In addition to hydrogen sulphide in biogas, there are several hundred other compounds in trace amounts, among them organohalogen and organosilicon. They can cause the destruction of installations and devices for the energy use of biogas, raising the operating and investment costs for treatment by various methods [3][4][5][6][7][8][9][10][11][12][13][14][15][16] . Commonly occurring in sewage sludge organosilicon compounds -siloxanes play a special role.…”

The Role of Mineral Phases in the Biogas Production Technology

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