Cost Effective Use of Heat Cost Effective Use of Heat RecoveryRecoveryTony Cotton

Johnson Tiles• Formed in 1901Formed in 1901

• One of the UK’s largest tile One of the UK’s largest tile manufacturersmanufacturers

• Up to late 1990’s – 3 sites in Up to late 1990’s – 3 sites in the Tunstall areathe Tunstall area

• Operations consolidated Operations consolidated onto one site in 2001 with onto one site in 2001 with £35m investment£35m investment

• Highly automated process Highly automated process consuming ~1,500 tonnes of consuming ~1,500 tonnes of raw materials per weekraw materials per week

• 4,500,000 m4,500,000 m22 of tiles per of tiles per annumannum

Why Save Energy?

• Reduce the environmental Reduce the environmental impact of energy usageimpact of energy usage

• Protect the world’s resources: Protect the world’s resources: – the UK consumes 8% of oil the UK consumes 8% of oil

resources & 4% gas resources resources & 4% gas resources every yearevery year

• To reduce our carbon footprintTo reduce our carbon footprint• To meet legal obligations of To meet legal obligations of

climate change legislationclimate change legislation• Good business sense - to Good business sense - to

save money & improve save money & improve profitabilityprofitability

Energy UseEnergy Use

• 126 GWh of gas per 126 GWh of gas per annumannum

• 21.5 GWh of 21.5 GWh of electricity per annumelectricity per annum

• All firing by continuous All firing by continuous gas roller-hearth kilnsgas roller-hearth kilns

• All production is fast All production is fast once-fired using gasonce-fired using gas

• Slowest firing cycle is Slowest firing cycle is 1 hour & fastest ½ hour1 hour & fastest ½ hour

The problem of waste heat““Surplus industrial heat should be better Surplus industrial heat should be better exploited. Industrial plants often generate exploited. Industrial plants often generate large amounts of high quality heat as a by-large amounts of high quality heat as a by-product. product.

A comprehensive heat strategy must A comprehensive heat strategy must include ways to ensure this heat is reused include ways to ensure this heat is reused wherever possible. In some cases wherever possible. In some cases industrial firms can reuse heat in their own industrial firms can reuse heat in their own processes.”processes.”

““The Heat is On”: CBIThe Heat is On”: CBI

Nothing new!• Waste heat has been Waste heat has been

used for decades!used for decades!

• Heat exchangers on Heat exchangers on tunnel kilns provided tunnel kilns provided space heatingspace heating

• Exhaust gases Exhaust gases preheated spray preheated spray driers to save gasdriers to save gas

Kiln Heat Recovery System

• Retrofit on existing roller kiln in 2008Retrofit on existing roller kiln in 2008• Applicable to any continuous kilnApplicable to any continuous kiln• Heat exchanger in rapid cooling zoneHeat exchanger in rapid cooling zone• Combined with heat extracted from slow & final Combined with heat extracted from slow & final

cooling zonescooling zones• Recovered heat ~200°C into gas burners as Recovered heat ~200°C into gas burners as

combustion aircombustion air

Energy Savings

• Since installationSince installation– Saved: Saved:

>£83K of gas>£83K of gas

>4,000,000 kWh of >4,000,000 kWh of gas (9% of the gas (9% of the kiln’s gas)kiln’s gas)

>750 tonnes of CO>750 tonnes of CO22

emissionsemissions

Payback estimated Payback estimated ~3 years~3 years

Current SiteInnovative use of waste Innovative use of waste heat:heat:

– Excess heat from kiln Excess heat from kiln fan platform used for fan platform used for space heatingspace heating

– Warm cooling air Warm cooling air used for two process used for two process driersdriers

– Ducted hot air to Ducted hot air to replace electric replace electric heating in canteenheating in canteen

Important Considerations• Use for heating is Use for heating is

seasonalseasonal• New buildings require New buildings require

little space heatinglittle space heating• Old buildings have Old buildings have

high heat loss & need high heat loss & need to consider insulationto consider insulation

• Target heat recovery Target heat recovery for use in 24/7 for use in 24/7 processprocess

• Minimise creation of Minimise creation of airborne dustairborne dust

Training & CommunicationTraining & Communication• Involve the workforceInvolve the workforce• Continuous Improvement Continuous Improvement TeamsTeams

• Energy CITEnergy CIT• Departmental Energy Departmental Energy ChampionsChampions

• Encourage suggestionsEncourage suggestions• Regular bulletins & Regular bulletins & postersposters

• Newsletter to inform of Newsletter to inform of improvementsimprovements

• Home energy-saving tipsHome energy-saving tips

Energy PerformanceEnergy Performance

130

135

140

145

150

155

160

165

170

175

180

185

190

195

200

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Ener

gy (G

Wh)

46000

48000

50000

52000

54000

56000

58000

60000

Sale

able

Ton

nes

Total Energy

Saleable Tonnes

Carbon Footprint 2009Carbon Footprint 2009

Down 7.8% on 2008Down 7.8% on 2008

66% from gas consumption

33% from electricity consumption

1% from company road vehiclesNote: Excludes deliveries & distribution

of CO2 reduction in 2009

Specific Energy ConsumptionSpecific Energy Consumption

20002000 4,519 kWh/tonne4,519 kWh/tonne

20102010 3,143 kWh/tonne3,143 kWh/tonne

30% 30% Reduction of Reduction of SEC in CCASEC in CCA

Future Opportunities

• Evaluate CHP systems Evaluate CHP systems

• Heat recovery as standard Heat recovery as standard

on kilnson kilns

• Heat exchangers on kilns Heat exchangers on kilns

for space heatingfor space heating

• Main kiln exhaust Main kiln exhaust

scrubbing to use heat in scrubbing to use heat in

spray drierspray drier

• New concept of kiln New concept of kiln

exhaust controlexhaust control

QuestionsQuestions

EMS 40817

www.johnson-tiles.comwww.johnson-tiles.com

www.material-lab.co.ukwww.material-lab.co.uk

FM 26818

2008

2009

2010