Fuel for Furnace + Efficiency Increase

What's wrong with natural gas?

What about pre-heating the oil?

What about pre-heating the combustion air too?

well, we do preheat the oil to 120 C to reduce the viscosity. but still because of the escalation of fuel prices, there is a need for substituting the fuel or maybe blending the fuel with some other low cost fuel.

thought of considering biodiesel also, but the biodiesel costs 3 units ( INR) more than furnace oil, even though the viscosity is low, yet the calculation for 90,000 litres of consumption in a month, the price again comes out more.

------------------x--------------x-------------x-------------------x------------

Where is your location? Can't you get natural gas there, or think of making producer gas from coal. How you preheat oil? Your furnace air fans are induced or forced? Do you preheat the air as suggested by PWSlack? Do you have recuperators installed to recover waste heat going up to stack as suggested by RAMConsult, it can be used to preheat the combustion air as well as fuel going to furnace.

@pritam sir :

1)location nagpur , india. no, natural gas is not available as in this industrial reason, there is no pipeline. cant afford for horton sphere.

2) preheat is through plate heat exchangers installed in the burner itself. electricity

3) we have induced air. primary air is through burner. secondary air is from the flue gas recycle. so, there is no preheating of primary air. please suggest the viability of heating the primary air.

4) yes, we have 7 zone. in 6 zones we have burners and in 7th zone, where less heat is required, we have waste heat recovery, but it is not much effective. w/o WHR, we get the temperature, 99 whereas with it we have 127. so although we have a little change yet the effectiveness is in question.

5) sir, for producer gas, i tried, but i have not got the proper literatures for it. need to go for deep search. any help on this will be appreciated. coz, for the producer gas, i have to give a total report with economic feasibility, environmental laws, design, cost, and return of investment, and as i am quite new, i dont have idea abt it.

With WHR 99 to 127 degree is not little. if you don't recover, anyway it is going to waste. For improving effectiveness, just check whether heat transfer area are clean and whether you can increase heat transfer area within the allowable pressure drop.

Producer gas is used in large scale at JSPL Raigarh steel plant. I don't have much idea about technology. I think you have proximity to coalieries.

yes sir, the coal mines are very near and i am pretty sure, we can set up a producer gas plant.

but i am looking for the design, aesthetics and calculations part

It seems wasteful to send all that heat up the stack. Do you have any heat-recovery on the exhaust gas stream, or insulation on the furnace? Since you are in the food industry do you have any waste food processing oil that can be blended into your fuel oil stream?

Frito-Lay in the US is working on high energy efficiency food factories:

http://www.pewclimate.org/docUploads/PEW_EnergyEfficiency_PespsiCo.pdf

Perhaps they'll share some info with you.

First, in order to keep the nozzles clear you can reduce the viscosity of the oil by heating it. That can be done with a hot water circulation through copper pipes. For increasing the efficiency of your oven, you can use a convection fan like large commercial electric ovens. Using a convection fan will make the temperature consistent throughout the interior of your oven.

yes we do have electric heating supply to the nozzle so that the nozzle wont clog, but still there is clogging because of high amount of high carbon chain wax like compounds. Have used furnace oil oxidisers also, but the effect was not there.

and , we have circulation fan for the entrapment of moisture. as triatomic molecules give the maximum amount of heat for radiation and H2O being a good greenhouse gas , the oven manufacturer did it in the beginning itself.

thnx nehw !

Dear Gent,

In my opinion you have to shut down the boiler for internal tube cleaning, but I would to ask you 2 questions,

1. Do you soot blower in the Boiler?

2. Is there any atomizing steam in burner fuel?

If you those (above mentioned) would not have any low efficiency.

Regards,

nice suggestion alfahad. !! great one i will say.

1 ) no soot blowing is not done. i will refer to the design for the possibility. thnx for it. i will reply to you , it i would be able to complete it.

2) atomizing steam is not used in the burner fuel, do u have any literature regarding it ? or can you help me with this ? i can send u the required details..

my dear

in my plant one package boiler has tow types of fuel, one natural gas and other one is C5(pentane) but we were facing a lot of problem of boiler effeciency and consuming high fuel, we used to shut donw it and clean tubes by steam, themn we stopped using liquid fuel.

in my new boiler we recoomended atomizing steam of Meduim pressure steam.

refer to link belwo it might be useful for you.

http://aalborg-industries.com/press_room/documents/KBSA_datasheet_MAR08.pdf

I hope it will help you.

regards,

thanx a lot buddy,

can you tell me by what percentage you have got the results on your favour. i mean the % of fuel saved per unit ton or per day consumption.

u mentioned that you are you have stopped using liquid fuel as of now. can you say which fuel are you using now ?

Sorry, I think that you have sent this message to me by accident. I'm a Civil Engineer, not a Mechanical Engineer, and I know very little about furnaces and ovens fired by oil.

Please have a good day!

===CaptMoosie

working on the same mate .. the basics say

1. if the heat is through radiation, then, we must look more for triatomic molecules, like H2O vapours, CO2, means, complete combustion is necessary and trapping of moisture using turbulence fan is important. ( heat through radiation is max.. e = σT^4)

2. preheat the air, look for co-generation.

3. keep the flame length short. this will result in less fuel consumption.

4. as said earlier by experts, introduction of steam in heavy fuel oil is good.reduces consumption by about 20 %

5. use fuel additives, oxidisers. search in google in your country. you will definitely find one.

6. use fuel gas analysis and see the amount of oxygen in the fuel analysis. it shouldnt be more than 2 %. control the amount of excess air. if you dont have flue gas analyses, you can see the chimney and try to balance between black smoke and white smoke. black smoke is incomplete combustion, white smoke is too much of excess air.

7. introduce inerts inside the oven and see for heat loss. block the leakages.

8. do you have a waste heat recovery zone ?

you can send me the construction of your oven and further analysis is procedure .