Furnace specs

[mcnabda]

I am looking into designing boiler and superheater furnaces fueled by an organic waste stream. Their is a high concentration of cyclohexane at 37 wt% with the remaining being H2 and methane in a 16:42 ratio. I wanted to know if the high level of cyclohexane can be tolerated in boiler and/or superheater furnances under normal operation. If not, what concentration of CH could be tolerated in the furnaces.

 

[owg]

Various refiners have burned hydrogen rich gas, and also naphtha streams as fuel. Cyclohexane has no special properties that would make it a poor or dangerous fuel. Your main problem may be deciding whether you are to burn gas, liquid, or 2 phases. The two phase design may be tough. I would suggest a knock out pot, burn the off gas in some burners, and burn the liquid in other burners. However a burner vendor may be able to provide a mixed phase burner.

 

[boilerguy]

I'll agree with owg in that there is nothing sprecial about the cyclohexane or H2 that would prevent using them as a fuel source in a boiler or furnace. What are the physical properties of your waste stream (temperature, pressure)? If there is sufficient pressure, then you could use atomizing steam to help vaporize any liquid that might be present in the stream. I don't know the current market price for cyclohexane, but for a stream with 37% CH in it and the rest being H2 and methane, I sure would look into recovering the cyclohexane. It seems like it would be a very easy separation, and much more cost effective than building a furnace or boiler and using it as a fuel source.

 

[zwsa06]

My previous assignments in an acrylic acid and maleic anyhdride plant used furnaces to incinerate the waste streams. Acrylic acid waste streams (about 48% in DMP) with several other acrylate streams were incinerated at 1100degC in an Oscatz furnace. The only limitations were that the streams clogged up due to poor steam jacketing on the the residue piping. The other problem I forsee is maintaining the calorific value of the liquid waste stream unless you have a big enough gas stream to diffuse the swings. Hope that helps.