Reduce energy costs and 2 emissions. - · PDF fileBuhler energy audit reveals opportunities. ... 890 Steam boiler Natural gas 2310 Legend ... – Process energy generated from shells

Reduce energy costs and CO2 emissions.Energy-efficient solutions for chocolate and cocoa production.

It all starts with an in-depth process analysis. Buhler energy audit reveals opportunities.

The energy audit can be viewed as a starting point for

improving efficiency. It helps to provide a picture of the

current situation of all the product and energy streams

of a production plant. For this, Buhler uses a specific

approach, known as the ‘Pinch’ method.

At the heart of the Pinch method – which is recom-

mended by the Swiss Federal Office for Energy – is the

process itself. But another important point is that this

approach also allows economic factors to be considered,

e.g. desired pay back time. The Pinch method therefore

not only helps to optimize a production plant in terms of

2 BUhlER EnErgy-EffIcIEnt solutIons

energy, but also economically, i.e. the plant is energeti-

cally optimized to the economic criteria of the processor.

The most important aspect of the entire energy analysis

is detailed knowledge of the process, which means that

suggested measures for improving energy efficiency will

be verified by Buhler process experts regarding their

technological feasibility.

The result of the energy audit offers a clear picture of all

energy and product streams that are relevant for the pro-

duction of your products. The Sankey diagram shows the

production process in terms of energy flows, and is thus

Buhler offers customers a seamless range of products and services, from raw cocoa beans to the

finished moulded chocolate articles. The company’s philosophy is to support customers at every

relevant step. Buhler regards climate change as a call to create new services and solutions. That

includes analyzing the current situation, defining relevant and appropriate measures for improving

efficiency, implementing the proposed measures and, finally, checking whether the implemented

measures achieve the proposed targets.

Analysis Definition Implementation Control

a perfect starting point for defining measures for improv-

ing energy efficiency.

Buhler process experts will work out a catalog of

measures which contains proposals as to how the en-

ergy efficiency of your plant can be improved. For these

measures, the economic criteria that you specify, such

as investment or desired pay back time, will be consid-

ered. Furthermore, since Buhler process experts are

deeply involved in the energy audit process, Buhler can

guarantee that all proposed measures can also finally

be implemented without affecting the product quality or

production reliability.

Primary energy DistributionTransformation Production line A + B

5210

1160

10 Air cooler

Losses

1380

4210

Water cooler

Feed water preheatExhaust air

Feed water 89050

890 Steam boiler2310Natural gas

Legend

Electricity

Natural gas

Steam 10 bar

Recirculated water cooling at 45 °C

Recirculated water glycole cooling below 20 °C

Losses

22150 20380

Steam distribution

2700

16520

260

1300

3860

80

50

80

390

310660

410

1760

1150

Blocking off & cooling

Tempering

Grinding & storage

Winnowingshell handling, storage,

aspiration, nibs handling and scaling

Exhaust air 10050

Compressed air

Storage & conveying

Intake, cleaning, aspiration

Debacterizing

RoastingSteam condensate

1040

Losses

All streams in MWh/a

Optimized chocolate mass production line with a production capacity of 1,000 kg/h.

Pinch evaluation and consideration

of economic criteria.

BUhlER EnErgy-EffIcIEnt solutIons 3

Sankey diagram: energy and product streams at a glance.

960

940

920

900

880

860

840

820

800

0 20 40 60

Yearly cost [kF/y]

deltaT min [°C]

Economic criteria:Yearly cost 808. [kF/y]

250

200

150

100

50

0

0 1000 2000 3000 4000

Temperature [°C]

Heat rate [kW]

1,660 kW primary energy demand

1,750 kW, 1,040 kW from exhaust air

Heat recovery approx. 1.1 MW

new approaches to cocoa processing.Energy-efficient debacterizing and roasting systems.

Process configuration for debacterizing

cocoa beans.

A newly developed STP™ (short-time-peak-pressure)

process allows shorter retention time in the reactor and

significantly reduces the specific steam consumption.

Furthermore, a process configuration in which the de-

bacterization step is situated after the roasting process

enables additional savings in steam consumption. Overall

savings of up to 50% for the debacterizing process step

can be achieved.

Heat recovery systems designed for high efficiency.

Specialized heat recovery systems for the Buhler Barth

TORNADO drum roaster and RoaStar™ fresh air roaster

provide savings of between 15–30% of the primary en-

ergy demand.

The heat recovery system for the Buhler Barth TORNADO

drum roaster consists of two main components. Firstly

the heat exchanger itself, which is specially designed

to suit the air volume and temperature used. Secondly,

a specialized gas burner application which enables the

utilization of preheated combustion air. The heat recovery

systems for the Buhler RoaStar™ fresh air roaster are

designed on the principal of a double water circuit. This

enables the utilization of at least an additonal 10°C of

heat recovery temperature compared with a single water

circuit heat recovery system. heat recovery systems for

Buhler Barth roasters are designed to realize a payback

period of approx. 2–3 years (at 7,000 h/a production time

and 3.5 Euro-Cent/kWh).

Savings energy and CO2 emissions.

5.5

6.0

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

psteam 8 bar psteam 6 bar

reduction of process time approx. 10sec. (about 25%)

0 5 10 15 20 25 30 35 40 45 50

Overpressure [bar]

STPTM

Cycletime [s]


Buhler BarthDebacTM System.

Shorter retention time due to STP™ (short-time-peak-pressure) process.

Debacterizing and roasting processes are decisive

factors when it comes to saving energy and costs.

However, common systems only make use of a

fraction of the energy they consume. Buhler Barth

debacterizing and roasting systems are more clev-

erly designed. They not only convince with their

quality, throughput and total productivity, but also

by using energy efficiently.

RoaStar™type

Yearly energy savings [€]*

Reduction of CO2 footprint (t/a)**

4t/h 150,000 850

3t/h 95,000 540

2t/h 68,000 390

1t/h 41,000 230

0.5t/h 23,000 130

Efficiency degree of 90% considered* cost of energy 0.035 €/kWh @7000 h/a, ** natural gas 200 g/kWh


Cooler 1

Fresh air

Heater 1

Heater 2

Cooler 2

Exhaust Air

100°

90°

80°

70°

60°

50°

40°

30°

20°

10°

90°

72.5°

66.5°

Air delta 17.5°

71°

65°

47.5°

delta 4.5°

Air delta 17.5°

30° 30°

delta 4.5°

Air delta 17.5°

47.5°53.5°

49°

55°

90°

Air delta 17.5°

72.5°

Exhaust air 90° –> 55° Fresh air 30° –> 65°

Water

Water

Temperature profile – heat recovery system for RoaStar™ fresh air roaster.

Buhler Barth RoaStarTM continuous fresh air roaster. Buhler Barth TORNADO drum roaster.

heat recovery system for Buhler Barth RoaStarTM.

heat recovery system for Buhler Barth TORNADO drum roaster.

Specialized gas burner for Buhler Barth TORNADO drum roaster.


Cocoa shell combustion system.

Cocoa shells are the future source of energy in cocoa

processing. The advantages of generating energy from

cocoa shells are manifold. Firstly, enormous savings

in the cost of energy can be achieved by utilizing the

cocoa shells which are produced as waste during cocoa

processing. Secondly, by utilizing cocoa shells as a

source of energy, modern cocoa processors are able to

reduce their carbon footprint tremendously. Especially in

combination with the RoaStar™ and Debac™, which are

steam based roasting and debacterizing systems, a ther-

mally self-sufficient processing system can be realized.

That means all the thermal energy required for roasting

and debacterizing cocoa beans is generated from the

cocoa shells. Furthermore, modern cocoa processors

are independent of fluctuations on the energy market as

no fossil fuel is required and calculation of future produc-

tion costs is more accurate. As the EU sponsors projects

designed to save fossil fuels, producers within the EU

can essentially benefit from partial government and EU

funding of the capital that they spend on cocoa shell

combustion systems.

Key criteria in cocoa shell combustion.

From a commercial and ecological viewpoint, two main

criteria must be fulfilled by a shell combustion system.

Trouble-free operation must be ensured with a main-

tenance requirement that is acceptable to the cocoa

processor. From an ecological viewpoint, the emissions

caused by combustion must be within the acceptable

A natural source of energy.Cocoa shell combustion.

Cocoa shells are an inevitable by-product when it comes to cocoa production. Buhler has developed

a tailor-made combustion system to generate energy from cocoa shells. What was formerly a waste

product is thus turned into an energy source that even allows the design of thermally self-sufficient

roasting and debacterizing processes.

Savings energy and CO2 emissions.

RoaStar™type

Yearly energy savings [€]*

Reduction of CO2 footprint (t/a)**

4t/h 490,000 2,800

3t/h 368,000 2,100

2t/h 245,000 1,400

1t/h 123,000 700

0.5t/h 61,000 350

Efficiency degree of 90% considered* cost of energy 0.035 €/kWh @7000 h/a, ** natural gas 200 g/kWh


steam boiler or3-pass heat exchanger(with automatic cleaning feature)

secondary air-injection socket

low nox-firebox

recirculation over grate (optional)

moving grate

fuel supply via hydraulic direct-push rod or screw conveyer

primary air supply

automatic firebox de-ashing

Cocoa shell combustion system.

heavy duty moving grate.Combustion chamber for cocoa shells.

limits applicable to conventional biomass combustion

systems. Within the EU, the German Clean Air Act can be

used as a general benchmark.

In biomass combustion, particular attention needs to be

paid to the residual ash content and ash melting point

of the respective biomass. A combustion chamber grate

which is purpose-designed for the cocoa shell applica-

tion ensures complete ash incineration, preventing

caking on the combustion chamber grate, and guaran-

tees a constant combustion process temperature. At

the same time, it enables acceptable CO, NOx, and dust

emission values to be achieved, which are within the lim-

its of the Clean Air Act. In the presence of more rigorous

regional regulations, the exhaust air can be additionally

treated using common dust collection filters and cleaning

components. An automatic cleaning feature in the steam

boiler helps to avoid power loss as a result of steam pipe

contamination.

Advantages at a glance.

– less down time for maintenance

– Suits high ash content of cocoa shells (10%)

– Suitable for melting point of ash

– Optimizing of combustion behavior –

enough surface on grate – long afterburning effect

– No deposit on combustion chamber grate

– No performance loss due to deposits in steam boiler

Value added with autarchic roasting system.

– Used in combination with the optimized variants of

Debac™ and RoaStar™

– Appreciable cutting of energy costs

– Appreciable reduction of carbon footprint

– Process energy generated from shells

– Optimal utilization of shells – no extra disposal

– Emissions within acceptable limits of EU regulations

– Independent of fluctuations on the energy market

– Partial government and EU funding

Main features.

– Moving grate – special cocoa shell design

– low-NOx-Firebox

– Screw or water cooled direct push rod

– De-ashing rod below grate

– Water cooled grates

– large volume, heavy-duty construction

– Fully automatic de-ashing

Possible applications.

– Stand alone for RoaStar™ and Debac™

– Integrated into customer’s steam system:

– biomass combustion provides basic load

– peak consumption covered by gas or oil-fired

steam boiler

– e.g. steam for alkalization

– Redundancy configuration with gas or oil burner fitted

at combustion chamber for emergency operation


Buhler Barth RoaStar™ in operation with steam produced using cocoa shells.


Automation.

An energy-efficient automation process enables potential

reduction of energy costs through efficient planning and

monitoring of consumption. Accurate recording over a

long period of time allows the energy consumption to be

analyzed. Additional features, such as optimization of

energy consumption through automatic starting and

stopping of process lines or definition of user-specific

energy limits in combination with cost controlling, can

also be implemented.

– WinCoS.r2 measures the current energy consumption

and monitors this against a user-defined limit value.

Excessive energy usage is prevented.

– Each process line can be individually configured and

controlled.

– With real-time monitoring, the power factor compensa-

tion can be optimized.

– Actions performed by WinEnergy are stored in a

dedicated data logger to enable traceability of events.

– Measurement points can easily be added.

– long-term comparisons are possible at any time.

Active energy management.Efficient planning and real-time monitoring.

An efficient automation process is the prerequisite for saving energy and costs. The control system

WinCoS.r2 monitors energy streams and consumption in real-time. Energy costs can be properly

allocated to the products. The result: active energy management.

Modern control station of a chocolate processing line.

Real-time monitoring of energy consumption.

High efficiency motors for chocolate grinders.

By using high efficiency motors of class IE2 or IE3, an

efficiency increase of between 2–8%, even at partial

load of 60%, can be realized. The substitution of motors

requires very little adjustment. The exchange of motors

can easily be realized. however, further potential lies also

in the respective drive concept of the chocolate grinder.

There are various factors that influence the efficiency of

the grinder (see box). Buhler engineers are able to verify

the appropriate solution that fits perfectly to your ap-

plication. The result is a highly efficient solution that is

customized to meet your specific needs.

Advantages at a glance:

– Reduction of power consumption

– Reduction of electrical connected load

– Reduction of energy costs and CO2

Buhler technology for continuous improvement.Chocolate mass production and moulding.


Buhler is continuously on the look out for new technologies to improve chocolate mass production and

moulding. High efficiency motors for chocolate grinders and the new SeedMaster™ technology open up

further opportunities to save energy. Buhler chocolate grinders stand both for high product quality and

productivity. With the SeedMaster™, Buhler developed a new chocolate tempering process that enables

customers to reduce energy consumption by up to 75%.

Chocolate grinder Finer-V™ with high efficiency motors.

100

95

90

85

80

70

75

0,1 1 10 1000100

Nominal efficiency (%)

Motor output [kW]

10%

2%

0.75 kW to 375 kW

IEC 60034-30 (Ed. 1.0) 2008

IE 3IE 2IE 1

Comparison IE1, IE2 and IE3 efficiency class motors.

Action Savings

System installation or renewal

Efficient motors 2 – 8%

Optimum dimensioning 1– 3%

Efficient motor repair 0.5 – 2%

Drive system with frequency converter 2 –10%

Belt drive, gear 2 –15%

Quality power supply 0.5 – 3%

System operation and maintenance

Lubrication, settings 1 –5%

Energy saving potentials for grinders.

Secondly, – depending on the application e.g. for a filled

product – SeedMaster™ tempered chocolate from the

overflow can be fed directly to the depositor again, and

thus does not need to be de-crystallized and re-temp-

ered again (see flow sheet comparison). This results in

additional savings so that, when used for a filled product,

up to 75% of energy can be saved compared with a con-

ventional tempering system.

Advantages at a glance:

– Up to 40% lower electrical connected load

– Up to 75% reduction in energy costs

– Significantly increased product quality (e.g. fat bloom)


SeedMaster™ – new chocolate tempering process.

Through a seeding pre-crystallization, a large amount of

very small cocoa butter crystal seeds are mixed homog-

enously into a chocolate mass. This allows for prompt

crystal solidification and a build up of a compact crystal

network of the cocoa butter. The result is a product with

improved fat bloom stability, higher strength and signifi-

cantly better gloss.

however, the SeedMaster™ technology also offers high

potential for energy savings. Savings of between 40–75%

of energy can be achieved for two main reasons. Firstly,

the SeedMaster™ technology requires approximately

40% less primary energy in the tempering process itself.

Depositor

Depositor

Hopper

De-crystallizer

SeedMaster

Shell forming

Shell formingConventional

temper

machine

4000 kg/h

2880 kg/h

2880 kg/h

1120 kg/h (start 4000 kg)

TM

Comparison: SeedMaster™ vs. conventional tempering system. (Capacity of moulding line: 4,000 kg/h – filled product)

Moulding line with SeedMaster™tempering system

Conventional tempering system

SeedMaster™ tempering system in combination with Buhler Bindler MultiStar™ moulding line.

Bühler Ag

cH-9240 uzwil, switzerland

t + 41 71 955 11 11

f + 41 71 955 35 82

[email protected]

www.buhlergroup.com

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Reduce energy costs and 2 emissions. - · PDF fileBuhler energy audit reveals opportunities. ... 890 Steam boiler Natural gas 2310 Legend ... – Process energy generated from shells