Investigation of the formation of residual ash on candle filters

When coal undergoes combustion, not all the carbon in the coal may be consumed. This is due to improper mixing of reactants, proximity of cold surfaces and the desire to operate combustors at lower temperatures. Depending on the type of coal and the operating conditions of the combustor, there may be about 4--6% of unburned carbon in the refuse. This unburned carbon is carried along in the flow of gases and ash. If the combustion gas products are to pass through a high temperature gas filtration system, ash and unburned carbon are deposited on the wall of a candle filter. Today, candle filters are employed for gas cleanup at temperatures of the order of about 1500°F.;During surface regeneration operation using air, the amount of oxygen available for reaction is at least two orders of magnitude greater than that available in the combustion products. This oxygen, combined with the prevalent temperatures will cause burning of the previously unburned carbon. The heat generated will result in a significant local rise in temperature of the deposits where the oxygen is consumed. These temperatures may lead to local sintering which may then lead to formation of the residual ash.;The present research involves: (1) Estimating the carbon concentration in the ash deposit; (2) Developing a simple combustion model to estimate the volumetric heat generation rate; (3) Developing a numerical model to obtain the temperature profile in the ash deposit, during regular filtration and during surface regeneration; (4) Determining if sintering occurs in the ash deposit.

Name thesis:degree_name

MS

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical and Aerospace Engineering

Year dc:date.available

1998

Author dc:creator

• Simha, Sharath J.

Contributors dc:contributor

• Eric K. Johnson.

• Mechanical engineering
• Environmental engineering

Identifier

https://researchrepository.wvu.edu/etd/936

OAI identifier oai:identifier

oai:researchrepository.wvu.edu:etd-1939