3100089 uk system bakery web

7/30/2019 3100089 UK System BAKERY Web

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Flue gas heat recovery systems

or bakeries


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Recent studies have shown that ovens and

space heating are the two most energy

intense processes in a bakery.

Achieve energy ecient baking

Cutting carbon emissions

The 2008 Climate Change Act made Britain the

rst country in the world to set legally binding

carbon budgets, aiming to cut UK greenhouse

gas emissions by 34 % by 2020, compared to 1990

levels, and at least 80 % by 2050.

This is truly a very challenging target or all,including British industry which accounts or

approximately 25 % o UKs emissions.

Bakeries can take the lead

Every bakery is in the ideal position to actively

contribute to massive savings and work towards

achieving set targets whilst increasing its own

protability.

The bakery ovens are the largest users o energy

in any bakery, and the sophisticated controlssupplied by the oven manuacturer do a antastic

job, but much o the energy used is discharged to

the atmosphere through the ovens chimneys.

Up to 15 % recovery o lost heat & energy

By installing a compact stainless steel heat

exchanger directly behind the burner or bed o the

oven, or integrating it into the exhaust gas line or

ue, a bakery can typically recover around 10 % or

even more o the heat in the ovens exhaust gas.

This recovered heat can be used to provide aconstant supply o hot water or cleaning and or

heating the building in the cold months.

Alternatively the recovered heat can be used to

preheat the water in steam boilers or to provide

cooling or both baking trays and mixing areas.

Apart rom the use o a heat exchanger there are

substantial savings to be made by ensuring the

burners operate at their optimum eciency.

But there is a catch!

Relativecarbonemissions

fromo

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Energy use in Bakeries

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Annual variations in the chimney draughtAt maximum and minimum outdoor temperature and an average flue gas temperature of 180 C.

Year (months)

60

58

56

54

52

50

48

46

44

42

40

Jan Feb Mar Apr Maj Jun Jul Aug Sep Okt Nov DecChimneydraughtwith10metrechimneyheig

ht(Pa)

Maximum chimney draughtMinimum chimney draught

Mechanical venting

The Fig. shows temperature uctuations that

are dependent on the time o year

What is the catch?

Modern bakery systems control just about

everything that happens inside the bakery. Time,

temperature, humidity everything needed to

make perect bread, cakes or pastry.

But the bakery system cannot control the

atmosphere.

The atmospheric pressure, the outdoor

temperature, the season, even the wind have

major inuences on the draught in the chimney

into which the ue gases rom the ovens are

discharged.

I the weather and the ue conditions are working

against it, the sophisticated controls o the oven

will cause it to burn more uel or even worse

result in an uneven bake as unctuating draughtconditions results in variable burner output.

Installing a heat exchanger into the chimney rom

the oven creates a resistance in the ue and as

it cools down the ue gases it makes the natural

draught practically impossible.

Even without a heat exchanger, the variation

o natural draught will have a negative efecton the energy perormance o the oven. Burner

perormance, in terms o optimal combustion and

ame conormity, is essential or high eciency.

There is a solution!

An exodrat ue gas heat recovery system can

ensure that the needed draught is available to

ensure energy ecient baking results every day

throughtout the year irrespective o any external

inuences or changes in the required output.


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exodrat an

The purpose-designed exodrat chimney an

modulates the speed to maintain the optimum

pressure in the ue or the ovens whether the

system is in bypass mode or in heat recovery mode.

The exodrat ans are heat resistant up to 250 C on

continuous operation.

The controller

The EBC is an on-demand

controller that maintains a

precise draught by constantly

monitoring the pressure in the

ue or the burner and signaling

the an to adjust the speed ensuring

a constant and optimum pressure level

or the bakery ovens.

The XTP sensor

The XTP sensor reads the

pressure and signals the EBC

controller to obtain constant

optimum pressure in the ue

or the ecient operation o

the ovens.The dampers

The EKG Dampers are

used or balancing theair rom ume vents.

How it works


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Heating

Cooling

Hot water

Steam/

proong

The heat exchanger

The heat exchanger allows or selective heat

extraction rom bakery ovens and their ues.

When no heat is required rom the system, you

are able to bypass the heat exchanger. Usually

10-15% o the heat rom the oven extract can

be recovered, thereby saving energy.

Many possibilities

The exodrat chimney drat system can be used

in diferent congurations or bakeries:

y To achieve a constant and optimum

pressure in the chimney or single bakery

ovens or or multiple bakery ovens

connected to one chimney stack.

y To achieve design exibility in the ue/

chimney system.

y In connection with a heat exchanger

to provide heat recovery and optimum

perormance o single or multiple bakery

ovens.


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The exodrat chimney drat system is

a well-tested concept in mechanical venting o

commercial boilers and water heaters. The princi-

ple has been transerred to industrial bakery ovens.

An important point which is oten not appreci-

ated about any type o heating system is that the

lue has not only to exhaust the waste gas to the

atmosphere, but also to provide a stable operating

pressure at the oven lue outlet, oten under vari-

ous levels o loading, to ensure that the air ratio to

the combustion is optimal.

The exodrat chimney drat system guarantees the

pressure is kept at the required level at any given

time - irrespective o changes in heat loads or

external inluences.

A stable and optimum pressure in the lue and

chimney increases the eiciency o the oven, the

perormance o the bakery oven and allows or

consistent baking results, independent o weather

conditions, amount o piping or lue diameter.

Even without utilizing the saving possibilities o a heat exchanger, a stand aloneexodrat chimney drat system oers great opportunities to save energy and waste.

Controlling the draught


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7Design fexibility and cost savings in new installations

y No need or individual ue gas chimneys.

y Long horizontal ue runs are possible.

y

Flexibility o design allows or placement o ovens where you want them andplacement o chimneys where you want them.

y The height o the chimney can be reduced i needed, improving the

aesthetics o the building.

y The chimney diameter can be reduced whilst guaranteeing the draught.

Minimal ue size = optimum utilization o oor space and dramatic reduction

in the area o the roo being penetrated.

Reduce operating cost

y Modulating system keeps running costs very low.y High quality components ensure long lie and low maintenance costs.

y The only system that guarantees the energy eciency o the oven whilst

recovering the heat.

y Reduced waste due to even bake.

Enables heat recovery

y Savings o up to 15 % on heating costs can be made through heat recovery

and mechanical draught systems.y Recovered heat can be used or heating, cooling, a constant supply o hot

water or cleaning or to preheat the water in the steam boilers thereby

increasing the savings.

Enabling Quick Return On Investment

y Technology one o the ocus areas in stage 2 o the Industrial Energy

Eciency Accelerator under Carbon Trust (Bakeries).

y Payback usually within 3-4 years depending on operational characteristics o

the bakery.

$


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exodrats extensive product range is based on more than 50 years o experience and

knowledge in the eld o combustion and chimney drat technology.

Our products are known or high saety and quality and were helping to set the standards

and requirements or drat technology.

exodrat products are all ully documented in accordance with current national and

international standards and are sold in more than 40 countries to small domestic

replaces in private homes to larger commercial and industrial boiler installations.

exodrat Ltd.Unit 3, Lancaster Ct., Cressex Business Park , GB- High Wycombe HP12 3TD

Tel: +44 1494 465 166, Fax: +44 1494 465 163, [email protected], www.exodrat.co.uk

3100089-01.1

2.

Fotos:exodraft&sxc.hu

Frequently asked questions

Is there a system or my bakery machine?

There are exodrat Flue Gas Heat Recovery Systems

available or every manuacturers bakery ovens and

systems, new or old and the systems are suitable or

all types o uel.

What about the design o the system?

Based on the oven type and size(s), the operational

characteristics o the bakery and the ue design,

the Flue Gas Heat Recovery System is calculated to

match the exact requirements o the entire system.

Is the an system heat resistant?

The an and the control technology can be used

at temperatures o up to 250 C. In the case o the

special high-temperature version, the maximumtemperature is 350 C in this case, it is not the

temperature o the oven that is the relevant actor,

but the temperature o the exhaust gases at the top

o the chimney stack. This is usually approximately

60 % o the baking temperature. The temperatures

are checked in all circumstances at the design stage.

Can I extract fue gases and baking umes

through the same stack?

Technically you can collect ue gasses and baking

umes through the same stack, but attention mustbe payed to the content o the baking umes in

order to prevent a build up o oils and acids. This also

depends on the local customs regarding recipes and

breads being baked. In the UK it is widely concluded

that it is saest only to recover rom the ue gases.

How do I clean the system?

The an unit is equipped with a ully hinged cover

or simple maintenance and cleaning. The heat

exchanger is easily opened and is cleaned by means

o high pressure water.

What about at and oil in the fue gases?

I needed, we use our grease ans expecially

designed or easy discharge o oil through the

bottom o the an.

What happens i the system breaks down?

The exodrat Chimney Fans are extremely sae

to operate and breakdowns are very rare. I a

breakdown should occur, the burner is switched of

by the ail-sae mechanism built into the automatedcontrol.

The installation o a bypass an in the top o a

parallel chimney can be done to ensure constant

operation in case o an ailure.

In the unlikely event o overheating the water vessel,

the overpressure valve will bring the steam or hot

water out o the system.

Where have these systems been installed?The last 3-5 years have seen a dramatic increase in

installations in single oven bakeries and multiple

oven bakeries, primarily in Mainland Europe.

3100089 uk system bakery web

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