UC-Irvine Meeting 030205 1 Identifying Energy Saving Opportunities in Process Heating through Waste Heat Recovery and Power Generation Bryan Warren Southern

UC-Irvine Meeting 030205 1

Identifying Energy Saving

Opportunities in Process Heating

through Waste Heat Recovery and

Power Generation

Bryan WarrenSouthern California Gas Company

Chris CockrillDepartment of Energy EERE-ITP

Arvind ThekdiE3M, Inc.


Primary Energy Use in Industries

• Process/Assembly (P/A)

– Process heating

– Process Atmosphere - gases

– Machine drive (Pumps, Fans, Blowers, Compressors, Vacuum pumps, Other Electric Motor Driven Systems)

– Water and other utilities

• Building (HVAC, Lighting etc.)

• Boiler-Steam-Cogeneration


Energy Use Pattern for Major Industries


What Is Process Heating ?

• Furnaces• Ovens• Heaters• Kilns• Dryers

Supplying heat Supplying heat to materials using to materials using

for further processing in for further processing in manufacturing operationsmanufacturing operations


Energy distribution in a typical heating system

Furnace Heat Input

Heat inFlue Gases


How much heat is wasted?

60% of the total heat input is wasted in flue gases at

2000 deg. F.


Waste Heat from Process Heating Equipment

• Waste heat from furnaces, boilers, heaters etc. accounts for 25% to 60% of the total heat input.

• The waste heat is primarily in the form of combustion products or flue gases at varying temperature.

• The flue gas temperature depends on the process temperature and the equipment design.

• The flue gases may contain combustion products (CO2, H2O, N2 etc.) and, depending on the process operation, other contaminants such as SO2, particulates and corrosive gases

• For any one equipment the flue gas mass flow, temperature and composition may change during the operation.


Power generation using waste heat recovery

Considerations “Quality” of heat • Presence of contaminants (Corrosive gases, condensable,

particulates etc.)• Temperature and its variation• Mass flow variations (down-times, “start-up and shut-down time

etc.)• “Seasonality” of waste heat availability (i.e. food, forest products

industries)• Use of waste heat within the heating system or in process • Possibility of using heat within the integrated plant operations• Economics of power generation using waste heat (capital cost.

Operation and maintenance etc.)• Availability of reliable technology for low (<400 deg. F.)

temperature waste heat streams


Waste heat recovery methods used

• In-process (Most preferred)– Combustion air preheating– Charge heating– Water heating – Steam generation

• Within the system or plant (preferred)– Cascading of heat from higher to lower

temperature processes– Water or air heating for the plant– Steam generation– Absorption cooling

• Export (For very large installations)– Steam generation– Steam - Power generation


How to estimate waste heat availability?

Process Heating Assessment and Survey Tool (PHAST) can be used to

– Estimate total heat used by the process heating equipment used in a plant

– It can give values magnitude and temperature of waste heat gases from “quality” of The Department of Energy has developed a tool


Process Heating Assessment and Survey Tool (PHAST)


What is PHAST?

A tool that can be used to:

• Estimate annual energy use and energy cost for furnaces and boilers in a plant

• Perform detail heat balance and energy use analysis that identifies areas of energy use, efficiency and energy losses for a furnace

• Perform “what-if” analysis for possible energy reduction and efficiency improvements through changes in operation, maintenance and retrofits of components/systems

• Obtain information on energy saving methods and identify additional resources



• The Process Heating Assessment and Survey Tool (PHAST) was developed

by Oak Ridge National Laboratory in cooperation with the Industrial Heating

Equipment Association (IHEA).

• A subcommittee consisting of members from major industries (i.e.,

petroleum refining, chemical) and equipment suppliers acted as an advisor

during the tool’s development.

• Development efforts were supported by The Office of Industrial

Technologies Program (ITP) of the US Department of Energy (DOE).



Major Sections of PHAST

• Introduction

• Plant Equipment Information

• Furnace Analysis – Heat Balance

• Reports

• Transfer (Import/Export) of Data Files


Use “Plant Information”

section of PHAST to enter and

analyze the data for process

heating equipment

Process Heating Assessment and Survey Tool(PHAST)


The report shows:

• Estimated annual energy use

and estimate annual cost of

energy for heating equipment

(furnaces, ovens etc.)

• List of heating equipment and

% of total energy cost used

for each equipment in order

of annual cost of energy used



• Use survey forms to collect data

for each item listed in various

Tabs of the form

• Use instructions given for each

entry to collect the required

data

• Review values of energy use or

losses are for each major

category of energy use



The report shows

• Analysis of energy used in

various parts of a furnace

under a given operating

condition

• Comparison of energy use

for current operations and

with possible changes

(what-if analysis) in

operating conditions for the

furnace



•Enhanced heat transfer, •Temperature profile control•Optimal process atmosphere•Material handling/fixtures

•Air-fuel ratio control, •Use of O2 enrichment, •Air/Fuel preheating, •Turn down capability•Flame size, shape

•Optimum insulation•Radiation losses•Pressure control•Cracks, openings etc.•Cooling losses

PHAST – Resources and Guide for Energy Efficiency Improvement Opportunities


PHAST – Resources and Guide for Energy Efficiency Improvement Opportunities

•Air preheating•Load preheating•Steam generation•Cascading to lower temperature processes

•Draft – pressure control•Controlled “head” heating•Use of process models •Direct load temp. control

•Use of low-NOx burners•Flue gas CO control •Fugitive emission control


Energy Savers Tips for Industries

Visit Our Web Sites: www.energysavers.gov/industrywww.oit.doe.gov


Next steps

• Attend one-day end-user PHAST training to learn capabilities of PHAST and its use

• Attend qualified specialist training to become a qualified trainer to teach others how to use PHAST. This is a 2 to 2 ½ days course offered at selected locations throughout the country

• Refer to DOE-OIT web page (www.oit.doe) for schedule and location in your area

• Sign-up for the end user training at the end of this meeting




Documents

UC-Irvine Meeting 030205 1 Identifying Energy Saving Opportunities in Process Heating through Waste Heat Recovery and Power Generation Bryan Warren Southern