1. Professional biogas production. Learning the lessons of
experience.
2. Substrates ............................. 4 Silage as a
cosubstrate ........ 10 Maize silage ......................... 14
Maize harvesting for biogas production ...........................
18 Contents Grass silage for biogas production
.......................... 24 Logistics and tractor design
...................... 27 Silage compression and fermentation
residue spreading ................ 30
3. 3 Now more than ever, cost-effectiveness is of paramount
importance for operators of biogas plants. And as well as equipping
and maintaining the actual biogas plant, the costs of the renewable
raw materials are a major factor here. Fortunately, professional
assistance is available to help with every aspect of substrate
sourcing, including harvesting, transporting and field preparation.
Contractors and syndicates have state-of-the-art equipment with the
reliability and performance to ensure fast harvesting with
near-zero wastage. CLAAS is here to make running your biogas plant
easier. For farms and agricultural service providers alike,
efficient biomass harvesting is vital. And CLAAS offers a range of
solutions that deliver this efficiency at every stage of the
process, not just harvesting itself but also transportation,
logistics and even data collection and analysis. This brochure
provides you with comprehensive information on every aspect of
biogas production. We hope that you will find it useful, and that
it will help you to achieve greater success in the future.
Introduction. Site logistics ........................ 34 Software
for biogas plants ........................ 36 Service
................................ 38
4. 4 Seeds, fertilizers, pesticides Harvesting and transport
Ensiling costs Transfer to fermentation tank Gas production
Electricity generation Residue storage Fermentation residue
spreading Transport and production approx. 50 % Biogas plant
Substrate production When people talk about the costs of running a
biogas plant, often their discussions focus on the cost of buying
and maintaining the hardware. But other factors are equally
important in particular, the cost of producing the substrate, the
quality of the substrate, and the efficiency of fermentation
residue reuse. These process steps before and after the actual
biogas production can account for as much as 50 % of total
operating costs (see figure 1). Figure 2 (see page 5) gives a
breakdown of substrate sourcing costs, using silage maize as an
example. Obviously the circumstances vary between different regions
and different plants, so the figures are only intended to give you
a rough idea. CLAAS machinery can be used in more than half of the
process stages involved in biogas exploitation, representing around
25 % of the value creation involved in the process of biogas
production from renewable resources as a whole. CLAAS naturally
seeks to offer machinery that delivers maximum performance at
minimum cost. But as well as optimizing existing designs, this also
means developing new machines, processes and combinations of
processes that can achieve further efficiency gains in substrate
sourcing. In the next section, Ibeling van Lessen of Stahmer, an
engineering firm based in Bremen, provides a general overview of
the biogas market in Germany. General situation. The introduction
in Germany of the Renewable Energy Law (known by the German acronym
EEG) in 2004 resulted in an explosion in the number of biogas
plants in the country, with an accompanying rapid rise in the
acreage devoted to growing the crops needed to feed these
facilities. A study by the Federal Ministry for the Environment
found that whereas in 2007 approximately 400,000 hectares were
devoted to energy crops, by 2008 this had risen to 500,000
hectares. However, sharp rises in raw material prices in 2007 led
to a marked slowdown in investment in biogas. These rises not only
put many individual biogas plant operators in a precarious
financial position, but also adversely affected the revenues of
equipment manufacturers. Figure 1: breakdown of biogas production
costs Substrate.
5. 5 Substrate Reforms to the EEG law which came into effect at
the start of 2009 are designed to reflect these developments. The
basic rate of payment for biogas-generated electricity was
increased, as was the bonus payable if the biogas was produced
exclusively from renewable raw materials, which have now in any
case also started to fall in price. The law also provides for
various other bonus payments (e.g. for waste heat usage in
accordance with the principles of cogeneration, for the use of
innovative technologies, and the use of animal manure), which have
helped make biogas generation more economically viable. As the
economy recovers from the recession which began in 2007, the number
of biogas plants can be expected to start rising steeply again. The
German Biogas Association expects the number of biogas plants in
the country to rise by 780 in 2009 alone, bringing the total to
some 4,600 sites with a combined output of approximately 1,600
megawatts. Larger facilities, with an output of over 500 kilowatts,
will not benefit directly from the reforms to the EEG, as the basic
price of electricity and the renewables bonus paid to these sites
will stay at the same level. Nevertheless, these too are expected
to grow in number, as it is not economical for smaller plants to
treat the biogas in a way that enables it to be sold to the natural
gas network. Over the next few years, new technologies for treating
biogas will become available, and the cost of these will fall, but
in the short-term, plants with an output of less than 500 kilowatts
are likely to account for the majority of growth. Figure 2:
breakdown of substrate sourcing costs, using silage maize as an
example Process step percentage of total costs 1 a)Installation:
production facility/interest payments 43 % 1 b)Installation: fixed
and variable machinery costs 17 % 2) Crop harvesting 12 % 3)
Transport from field to silo (distance 2 km) 5 % 4) Administrative
costs 3 % 5) Fixed and variable silo costs 13 % 6)Transfer from
silo to fermentation tank 7 % Total cost at fermentation tank 100
%
6. 6 Raw materials. The choice of raw materials used in biogas
plants largely depends on land yields. Biogas plants that use
renewable raw materials only make economic sense where large
amounts of dry matter can be produced on the available agricultural
land. The biodegradability of the crop is likewise obviously an
important factor, but most arable crops meet this criterion. Only
the wood polymer lignin is not broken down in the anaerobic
biological process (without the presence of oxygen). It became
clear early in the development of the biogas industry that maize,
in the form of silage, was the ideal raw material. This crop offers
high yields, and because it has been used for fodder for so long,
the problems of preserving it have largely been resolved.
Cultivation and harvesting technologies for maize are likewise
highly developed, and the large number of different varieties
available means it can be successfully grown in a wide range of
soil and weather conditions. For these reasons, maize remains the
dominant raw material for biogas production. Based on 2008 figures,
it accounts for around 80 % of renewable raw material usage by
biogas plants. However, if we look even a little way into the
future, it is apparent that maize silage alone will not meet the
biogas industrys need for renewable raw materials. The increasing
concentration of biogas plants in certain regions, and the enormous
increases in the average size of new facilities being planned in
recent years, mean that there will not always be sufficient land
for maize silage cultivation in the vicinity. Increased transport
costs will therefore offset the high energy content of the maize
silage, compromising its relative cost-effectiveness. Because the
ratio of water to dry matter in maize silage is high, transport
costs are disproportionately large; as a result, if the transport
distance is 20 kilometres instead of two kilometres, the total
procurement costs rise from 250 per hectare to 350 per hectare an
increase of 25 %, with a resultant impact on profitability. For
this reason, crop scientists are working hard to develop new maize
varieties with an even higher per-hectare energy yield. New
combinations of harvesting and transport processes involving HGV
haulage are also being explored with the aim of reducing overall
sourcing costs.
7. 7 Process steps. In the past, the issue of transport costs
was often disregarded in the planning of biogas plants, and it was
just assumed across the board that transport distances would be
between two and four kilometres. However, these days nobody builds
a biogas plant without first taking into consideration what
substrates are available, where they will come from and what terms
they can be purchased on. Common alternatives to maize silage
include cob-corn mix (CCM) and grain. Because these involve
harvesting only the fruits, as opposed to the whole plant,
production costs are higher, but on the plus side, dry matter
contents of 60 % and 90 % respectively are possible, significantly
reducing transport costs. As the distance between the harvest site
and the biogas plant increases, the cost advantage of maize silage
per unit of electrical output over alterative substrates falls, and
indeed, beyond a certain point turns negative although it must be
remembered that biogas facilities cannot be run on CCM or grain
alone. The high energy yield of grain does however make it well
suited to use in conjunction with maize silage. The grains must be
milled, crushed or ground, because the micro- organisms in the
biogas process are not able to crack them unaided. All this means
that in practice, for transport distances of between 10 and 20
kilometres, CCM is increasingly the most cost-effective option, and
where transport distances are over 20 to 25 kilometres, grain is
the best choice although there are regional variations. As one of
the leading manufacturers of harvesting machinery and tractors,
CLAAS is ideally placed to offer the equipment and processes needed
to facilitate effective substrate sourcing. Substrate
8. 8 A useful addition: rye whole-plant silage. Rye whole-plant
silage (rye WPS) has also proven its suitability for use in biogas
plants in conjunction with maize silage. Rye can be ensiled as a
green forage crop or when it ripens. Rye WPS with a dry matter
content of 30 % produces a similar amount of gas to maize silage.
When it is harvested as forage rye, maize is normally added to it,
and when it is allowed to ripen to the milk stage, it is normally
combined with Sudan grass, millet or sunflowers. These secondary
crops ripen at approximately the same time as the rye, and are
generally ensiled with a dry matter content of between 20 and 27 %.
It is always preferable to use a second raw material in the biogas
fermentation process rather than maize alone, as there is extensive
research to suggest that this significantly increases the
efficiency of the biodegrading process. However, rye does not
deliver the same yield as maize. We recommend growing just maize in
the first year, and then in the second year a rye WPS crop followed
by Sudan grass, millet or sunflowers. These three harvests in two
years will minimize the substrate risk, simplify slurry management,
optimize conditions in the fermentation tank and avoid the problems
of maize monoculture. Millet is particularly common in dryer
regions. Widespread trials of sweet sorghums and Sudan grass in
biogas plants are currently ongoing. Millet crops are much more
resistant to long periods without rainfall than maize, as they can
stop and resume their growth, and so the danger of premature
ripening is much less. Special biogas varieties are currently being
developed to maximize yield, but even these are not expected to
match the organic dry-matter yield of maize in good growing
conditions. The transport costs will therefore be higher, meaning
that millet crops will only be a viable alternative where they can
be grown near to the biogas plant, or in light soils that are not
suitable for maize cultivation.
9. 9 Sunflowers hard to ensile. Trials with sunflowers have
also been proceeding for some time now. These have shown that
sunflowers can, when properly prepared that is, with a short, fine
chop that breaks up the seeds be successfully used in biogas
plants, but that preservation is problematic. Ensiling sunflowers
on their own is not really possible, as the result is too liquid
and slushy to be packed effectively. Combined sunflower/maize
silage is more successful, but the difference in harvesting times
between the two crops brings its own set of problems. Grass silage
is also increasingly being used in biogas plants, but this requires
a heavy-duty feeding mechanism, as it can easily result in
blockages. As with rye WPS, grass can, when used in large
quantities, cause the slurry in the fermentation tank to become too
thick and separate into floating layers. However, used in
conjunction with maize silage, grass improves the effectiveness of
the biodegrading process. Chop length the crucial factor. Whichever
substrate is ultimately used, the way that this is preserved and
prepared is absolutely crucial. The organisms involved in the
biogas process are not capable of breaking their food down
mechanically by chewing it, so this has to be done for them. With
most plants, a chop length of around four millimetres seems to be
the optimum for ensiling and compacting. With forage rye and grass
silage, a chop length of 10 millimetres or less is advisable for
biological and technical reasons (faster and more effective
biodegradability without the formation of floating layers). This
ensures high-quality silage that will be effective in the biogas
process. In the case of maize, it is also important that the grains
are cut or crushed, so that the outer husk is broken. Grain is
generally milled for use in biogas production. Substrate
10. 10 Dr. Johannes Thaysen of the Schleswig-Holstein Chamber
of Agriculture provides an overview of the biological processes
involved in methane formation, and discusses the use of
cosubstrates. The process by which organic matter biodegrades
anaerobically can be divided into four basic stages (see figure 3).
The first of these is hydrolysis, which involves the breakdown of
long-chain molecules such as proteins or starches into simpler
organic building blocks. These are then digested by acid-forming
bacteria and converted into organic acids. The third stage is
acetogenesis, which results in the formation of acetic Silage in
biogas plants. acid, carbon dioxide and hydrogen the ingredients
necessary for the formation of the methane itself in the final
stage. A small proportion of the energy released by this process is
used by the microorganisms for reproduction, but 90 % of the energy
contained in the original substrate is present in the methane which
is what makes it useful as a fuel. Methane makes up between 50 and
60 % of the gas produced, with carbon dioxide making up the
remaining 40 to 50 %. The bacteria involved in this process, and
especially the methane microbes, have differing requirements as
regards oxygen, temperature, nutrients and pH levels. The type of
fermentation (wet or dry) and the plant type, dwell time in the
fermentation tank and volumetric loading rate also play a role.
Mixability and pumpability must be ensured, and all substrates must
be mechanically broken down into small enough particles to ensure
efficient biodegradability of the organic matter and prevent
separation into floating layers, which can interfere with the
working of certain types of digester reactors. From animal manure
to renewable raw materials. Agricultural biogas production evolved
from the use of liquid fertilizers. Initially, cattle manure was
the most widely used raw material, due to its ready availability,
and its good gas-producing potential as a result of its high
dry-matter content. Figure 3: schematic representation of anaerobic
biodegradation Raw material (proteins, carbohydrates) Hydrolysis
Simple organic building blocks (amino acids, fatty acids, sugars)
Acidogenesis Lower fatty acids (propionic acid, butyric acid) Other
products (lactic acid, alcohols, etc.) Acetogenesis Acetic acid
Methanogenesis H2 + CO2 Biogas CH4 + CO2
11. 11 Silage as a cosubstrate Figure 4: relevant properties of
fertilizer for biogas production (REINHOLD, 2005) Type DM oDM
Methane Methane content content yield yield1 % as % of (m3 /kg) (%)
DM oDM content x d Cattle manure 612 80 200 55 Pig manure 28 80 240
60 Poultry manure 4565 75 325 65 Cattle dung 2030 80 250 55 1)
Without air supply due to biological desulphurization. The key
criteria used to evaluate different substrates are dry-matter
content, organic dry-matter content, possible gas yield and methane
concentration in the biogas released (see figure 4). The
introduction of the Renewable Energy Law (EEG) in Germany in 2004
created a framework that made the use of renewable raw materials in
biogas plants economically viable. This policy aim was furthered
with the reforms to this law that came into effect at the start of
2009. As a result of these changes, significant changes in the mix
of substrates used by biogas plants can be expected. The following
criteria are used to evaluate the possible use of renewable raw
materials: Timely availability in sufficient quantities (crop
should be available over a minimum period of six weeks, to ensure
the fermentation process is consistent) Awareness of product
properties, such as e.g. dry- matter content, organic dry-matter
content, chop quality and ripeness Necessary preparation processes
(e.g. chopping of silage, crushing of grain) Cosubstrate costs
Nutrient content of fermentation residue. The value of this residue
can be offset against the production costs. Substrates for biogas
production. In principle, all arable crops can be used to produce
biogas. A high crude fat content corresponds to a high gas yield,
while sugars can be converted very quickly. On the other hand,
plants that combine a high lignin content with a low nutritional
value (e.g. straw, conservation grass) are not as suitable (see
figure 5, page 12). The range of technical variations in the
optimum process for different substrates can be seen by comparing
the cases of silage and grain. For example, where silage is used, a
large volume of water (600 to 700 kilograms per tonne) must be
added, and the amount of energy lost due to the ensiling process
and effluent formation must also be taken into consideration.
12. 0,5 0,4 0,3 0,2 0,1 0,0 Lignin content determines gas yield
Conservation grass Grass silage (extensive) Maize silage Grass
silage (intensive) Cattle manure 12 1 Without air supply due to
biological desulphurization. Type DM oDM Methane Methane content
content yield yield1 % as % of (m3/kg % DM oDM) Maize silage 32
(2835) 95 Whole-plant 40 (bis 50) 95 300400 5254 silage Grain 86 95
Optimum maize structure for biogas plants Figure 6: relevant
properties of different substrates for biogas production On the
other hand, where grain is used the dry-matter content of the basic
substrate can be lower. Where it is used in large quantities,
additional fluid may need to be added, possibly by recirculating
the biogas slurry. Grain substrates also do not need to be heated
as much, so they make an economical combination with pig manure,
which does require a lot of heating. In evaluating cosubstrates,
methanogenesis should also be taken into consideration (see figure
6). Factors such as dwell in the fermentation tank and volumetric
loading rate depend on how easily the substrate is broken down into
methane. Beets, for example, degrade very quickly due to their high
sugar content, meaning they spend less time in the fermentation
tank and that more of them can be packed in. Maize silage, by
contrast, is more fibrous, and so dwell times are longer and
volumetric loading lower. Proper substrate preparation, such as
crushing grain or chopping silage (JOHANNSEN, 2005) will increase
the rate of degradation and allow more effective use to be made of
available fermentation tank capacity. Indicators of silage quality.
The usefulness of different types of silage is determined by a
number of indicators (see figure 7). The most important of these
are dry-matter content and organic } Figure 5: methane yields of
various substrates Source: Oechsner and Lemmer, 2002
13. 13 dry-matter content. If dry-matter content is below
around 28 to 30%, fermentation effluent can form, resulting in a
significant loss of energy content. The latest biogas plants
generally place their silage clamps on a concrete base,
incorporating gutters to collect the effluent and channel it into
the fermentation tank. Crops such as millet and sunflowers always
produce such liquid when harvested, as a result of their low
dry-matter content, and are increasingly used as a substrate.
Inorganic content, especially soil residues, must be kept to a
minimum, as they do not contribute to gas production (essential
minerals and trace elements are an exception to this rule). Sand
and stones also reduce the amount of space available for the
fermentation process, and because they sink to the bottom of the
fermentation tank, they can interfere with the heating systems
designed to keep the substrate at the optimum reaction temperature.
As with animal feed, the digestibility (which in this case equates
to biodegradability) of the biomass determines the methane yield.
As the bonds in lignin molecules are largely indigestible, high gas
yields can only be achieved with substrates that have been
harvested at the right time. In starchy silages, the grain/cob
content is the key factor. Silage as a cosubstrate Experiments
conducted to compare maize silage that is ensiled naturally
(favouring lactic acid-producing bacteria) and maize silage made
with ensiling agents (which favour acetic acid-producing bacteria)
have shown that the silage stabilized with lactic acid neither
decomposes slower nor delivers lower yields in biogas plants.
Lactic acid is no less effective as a stabilizer than acetic acid,
nor is it less effective in releasing energy. In fact, because
lactic acid has a higher boiling point than acetic acid (122 C as
against 117 C), it is actually more effective. The most important
factors are that the forage be clamped immediately after
harvesting, and that the silage heap is properly covered to prevent
aerobic degradation and mould formation. Care should also be taken
to ensure that after opening, the silage face is kept as small as
possible. Silage quality is everything. The keys to efficient,
cost-effective silage production and storage are the intrinsic
energy content of the forage, how well it is clamped, and effective
fermentation without mould formation or excessive heat generation.
The wrong sort of fermentation can result in the presence of
detrimental microbes such as clostridia, listeria, yeast and moulds
which lessen gas yields. To ensure optimum quality right up to the
point where the silage enters the biogas fermentation tank,
high-quality crops must be harvested at precisely the right moment,
and properly stored in accordance with best practices in silo
management. More details about what precisely this entails can be
found in the next section. Figure 7: indicators of silage quality
for biogas production Indicator Unit Target level ODM content % of
dry matter 90 Sand content % of dry matter 2 Digestibility of
organic matter (HFT gas production), ELOS % of dry matter 75 pH 4.2
at 30 % Ammonia % of NH3-N 10 % Acetic acid % of dry matter2.0
Butyric acid % of dry matter0.3 Aerobic stability Days3
14. 14 Put more energy in. Potential cost savings in the silage
production process. The financial situation for biogas plant
operators in Germany has changed a lot recently, following the
reforms to the Renewable Energy Law and the subsequent sharp rises
in raw material prices. This has made it all the more important
that they understand all the ways that they can reduce their costs.
There are potential savings to be made at every stage, from the
installation of the equipment to the spreading of fermentation
residues. In this section, we will focus on the harvesting and
ensiling of maize. The principle is quite simple: any dry matter
that is lost before it reaches the fermentation tank cannot produce
any gas; as a result, the more effectively silaging technology can
cut out these losses, the higher the gas yield will be. What makes
good silage? The suitability of different types of silage for
biogas production depends on a number of factors (see figure 8).
The most important of these are dry-matter content and organic
dry-matter content. Below a dry-matter content is of 30 %, silage
effluent can form carbohydrate can easily dissolve in this, meaning
that a large amount of energy can potentially be lost. In maize
this is prevented by only harvesting the crop once it is properly
ripe, in whole-plant silage, it is prevented by ensuring a high
enough cob content, and with grass, the key is to allow it to wilt
sufficiently. If silage effluent is produced, this has to be
captured and fed back into the process. The level of inorganic
content, and especially soil residues, must be kept as low as
possible, as with the exception of essential minerals and trace
elements, they do not contribute to gas formation. As with animal
feed, the digestibility (which in this case equates to
biodegradability) of the biomass determines the methane yield. As
the bonds in lignin molecules are largely indigestible, high gas
yields can only be achieved if the substrate is harvested at the
right time. In starchy silages, the grain/cob content is the key
factor. As regards the acidification that occurs in the course of
the ensiling process, the aim is to favour lactic acid- producing
microbes (as, assuming adequate dry-matter content, these lower the
pH level to the point where all microbial growth is inhibited).
However, unlike with cattle feed, acetic acid can play an important
role in methane yield, and it can be present in much higher levels.
This is because of the key role that acetic acid plays in the
process of biodegradation. If this can be achieved by means such as
the use of ensiling agents, it will help ensure the quality of the
final silage by making it aerobically stable and free from
impurities (absence of mould, excessive heat generation).
15. 15 Maize silage Losses are often underestimated. Ensiling
is the process by which a plants sugars are converted into
preservative acids in the absence of oxygen. Even under optimum
conditions, this process inevitably results in a loss of dry mass
and energy content with an equivalent value of around 77 per
hectare (see figure 9). Below a dry-mass content of 30 %, silage
effluent starts to form, resulting in greater losses depending on
the chop length and the silo height, these can amount to up to 90
per hectare. And depending on the type of fermentation, how long
silage is stored, how and how often silage is taken out of the
clamp, and whether excess heat is produced, more energy can be
lost, with an additional value of up to 200 per hectare. In total,
poor ensiling can therefore result in monetary losses of over 500
per hectare. If this erosion of value was more obvious, then more
would be done to avoid it. Harvesting window by variety. Biogas
crop varieties ripen at roughly the same speed as varieties used
for animal fodder, and so should be harvested at roughly the same
time. Silage maize for use in biogas production should ripen to the
dough stage even in years where conditions are unfavourable. Late-
ripening varieties often have a higher yield by weight, but this is
accounted for by higher water content, so while transport costs
increase, gas yield does not necessarily do so. What matters for
gas yield is not absolute mass, but fermentable mass. Figure 8:
target levels of silage quality indicators for biogas production
Indicator Unit Target level ODM content % of DM90 Sand content % of
DM2 Digestibility of organic matter (HFT gas production), ELOS % of
DM75 pH4.2 at 30 % Ammonia % of NH3-N 10 % Acetic acid % of DM2.0
Butyric acid % of DM0.3 Aerobic stability Days3 Figure 9: monetary
losses in the maize ensiling process Not included: reduced gas
yield Cause Avoidability DM loss NEL in /ha in /ha Residual aerobic
fermentation Unavoidable 1 2 Anaerobic fermentation Unavoidable 58
116 5 12 Fermentation effluent Process-dependent 0 81 0 9 In-field
losses Process-dependent 12 58 1 6 Defective fermentation Avoidable
0 174 0 12 Excess heat generation Avoidable 0 174 0 12 Total Silage
maize 70 604 7 54
16. 16 This means that the harvesting window when the silage
maize is at the optimum ripeness, with a dry-matter content of
between 30 and 38 %, is relatively short. Depending on the
circumstances of individual biogas plants, it may therefore make
sense to plant different fields with varieties that ripen at
different speeds, or to stagger the harvesting of different fields
to reflect variations in the speeds at which the crop ripens due to
differences in soil type. Giving bacteria room to do their work.
Various studies have shown that chopping up silage more finely
will, all other things being equal, result in higher gas yields.
The choice of chop length should therefore balance this
consideration against the dry- matter content (compressibility of
the silage) given the silo height, and harvesting machinery fuel
consumption. The table in figure 10 suggests chop lengths for
different silo heights that will prevent the formation of
fermentation effluent, and limit the aerobic phase. The range of
suggested chop lengths is in theory between 4 and 9 millimetres.
Where grains need to be broken up smaller than this, they should be
put through a cracker roller after chopping is complete. The riper
the crop is, the more the grains need to be broken up. The same
applies to chop length: the greater the dry-matter content, the
more important it is to follow the recommendations of the table
above, as riper crops are more fibrous. This reduces
compressability (as grains are more resilient to crushing) and can
lead to lower gas yields (see figure 4, page 11). The
recommendations regarding the breakdown of fibres are the complete
opposite of best practice when making fodder silage, where the aim
is to preserve the integrity of the plants structure. If the same
silage will be used both as cattle feed and in a biogas plant, the
fibres should therefore not be broken down. Silo height Measure-
Silage Whole-plant ment maize silage Up to 3 m % of DM 2830 upwards
3540 upwards mm 96 6 36 m % of DM 3035 4045 mm 75 5 Over 6 m % of
DM 3538 45 mm 54 4 Figure 10: optimum DM content and chop lengths
of silage maize and whole- plant silage for various silo
heights
17. 17 Maize silage Special ensiling practices? The high daily
quantity of silage fed into the biogas plant (currently generally
between 3 and 30 tonnes) means that the silage clamp has to be
relatively large in terms of width, depth and height. And because
dry-matter content is often high, and the silage is therefore
finely chopped, the necessary compression often cannot be achieved
without side walls. If these are not present, then the silage must
be piled up to the correct height in a wide, gently sloping heap
that takes up a lot of space, so a clamp with fixed side walls
(ideally at an angle of 20 to 25 degrees) is a more viable
solution. With clamps of this size, the issue of how they are
sealed is also important. The practice of not covering the silo or
growing crops on top of it must be avoided at all costs. This
results in high losses of dry matter and energy, and rainwater
permeating the heap can damage the silage even in the lower layers,
by causing unwanted heat generation and mould formation. NUSSBAUM
(2008) conclusively demonstrates that given the current
production/procurement costs for maize silage, leaving the silo
uncovered does not make sense either financially or in terms of
convenience. Biogas plant operators need manufacturers to offer
larger tarpaulins that allow silage heaps of the size they need to
be covered properly. Gravel bags can be used to seal the edges, but
tension belts have proven to be a less labour-intensive alternative
to secure the covering in place. Silage hygiene. While maize is
relatively easy to ensile, its high sugar content means it has a
low buffering capacity, which can result in aerobic instability,
excess heat generation and mould formation all things which reduce
gas yield, and in extreme cases, can stop the biogas production
process entirely. For this reason, it is all the more important
that the advice in the section above regarding the way the silage
is packed and added to the clamp is followed. To avoid the risks of
aerobic instability and mould formation, liquid silage additives
approved by the DLG (German Agricultural Society) are available,
which are added to the forage during the harvesting process.
Conclusions. High biogas yields from maize silage depend on the
following factors: Dry-matter content above the level at which
silage effluent forms Adjusting chop length to suit the dry-matter
content of the forage and silo height Preparing the forage in a way
that ensures effective decomposition To achieve this, it is
important to know the current dry-matter content of the crop as it
is harvested (ideally through a real-time measuring system fitted
to the harvester), so that the chop length can be adjusted
accordingly. Only cold, mould-free silage will produce a lot of
gas. Particularly if the silage is in a heap without side walls,
the use of additives to prevent energy losses is also
indispensable. Large biogas plants, large clamps.
18. 18 Optimizing costs. With rising prices, every single litre
of fuel counts. As such, fuel economy has been a key consideration
in the development of the new JAGUAR. Improved weight distribution
in the chassis has allowed the ballast to be cut, lowering overall
weight. This, combined with a tyre pressure regulation system, has
enabled wheel slip to be reduced and traction improved,
significantly improving fuel economy. And because vehicle weight is
spread over an area that is up to 30 % larger, the machinery is
also less damaging to the soil over the long-term. The knife drum
is fitted with 36 curved knives in 830 and 730-horsepower models,
and with 28 standard knives for machines with an output of 623
horsepower or lower. The knives are always arranged in a V
formation. More versatility is available by specifying the heavy
duty CRACKER for enhanced corn cracking performance. The JAGUAR has
also been fitted with a range of comfort features, to ensure long
working days pass by effortlessly. Realizing potential savings. The
accelerator can be adjusted to blow harder or more gently to suit
the harvesting conditions. The distance to the accelerator is
variable between 2 to 10 millimetres, reducing energy requirements.
This quickly adds up to a total saving of between 5 and 10 % a
significant sum. Boosting biogas production. There is a direct
relationship between power and consistent chop quality and for
biogas plants, chop quality is critical to productive silage.
Harvester throughput has always a major purchasing criterion, but
these days efficiency is also becoming more and more important to
operators. A constant optimization and development process has made
CLAAS JAGUAR the number one in this regard. The new JAGUAR 900
Series incorporates valuable experience and brings maximum
practical benefits to the user. In recognition of the effectiveness
of the system, the JAGUAR recently received an award from the
commission of the German Agricultural Society. JAGUAR: the
definition of efficiency.
19. 19 JAGUARJAGUAR As a general rule, a shorter chop requires
more power, and so operators must carefully weigh up how long a
chop length they can get away with. This decision is best taken in
the field during harvesting, according to the ripeness of the crop.
Studies show that chop lengths of between 5 and 7 millimetres are
generally the most cost-effective. Speedy harvesting. CLAAS has
dramatically increased the horsepower of its machinery to meet the
specific needs of biogas plants. The new DOUBLE SIX twin-engine
layout in the JAGUAR 980 uses two six-cylinder units to develop a
maximum output of 830 horsepower. The high-performance ORBIS maize
headers can harvest up to 12 rows each 75 centimetres wide,
effortlessly harvesting over 300 tonnes of forage per hour. Now
transport logistics and silage compression become the key to
maximizing results. Higher quality, higher yields. Consistent chop
quality is essential to achieving the best possible biogas yields.
This means choosing the ideal chop length and ensuring plants and
corns are fully broken down. A V-shaped knife layout cuts the maize
while pulling it extremely closely to the shear bar. The clearance
to the knives can be adjusted to hundredths of a millimetre, and
this extreme precision ensures homogenous forage. The intake
rollers exert nearly three tonnes of pressure on the harvested crop
before the shear bar, ensuring superb compression. In the new
generation of forage harvesters, chop length can be set from the
cab. Maize can be cut in lengths from 3.5 to 13 millimetres with 36
curved knives, and from 3.5 to 15 millimetres with 28 standard
knives. And the crop intake of the new JAGUAR range is now nearly
30 % larger, meaning it will not become blocked even if the machine
is operated at its full output of 830 horsepower for extended
periods. V-MAX drum (36 knives)
20. 20 80M 100 125 JAGUAR model INTENSIV CRACKER Roller
diameter COARSE MEDIUM FINE Maize 12 22 mm Maize 3,5 12 mm whole
crop silage corn cob silage millet 3,5 12 mm 930- 960 950-
980Performance 930- 960 950- 980 930- 960 950-980 80 30 % M Medium
196 mm 100 125 30 % 30 % 100 L Large 250 mm 125 60 % 150 Diff.
Diff. Diff. Diff. 60 %Diff.30 %Diff. 930 940 950 960 970 980 CC
roller conditionV-MAX 36 V-CLASSIC 28 Knife drum Radial roller
deflector Prepress Shear bar condition Cracker clearance Knife
condition and knife type Knife/shear bar gap Grinding strip
Grinding base Revolution difference 20 / 30 / 60 % Grinding strip
Grinding base The INTENSIV CRACKER features cracking rollers with a
sawtooth tread plated in hardened chrome. 100 teeth with a diameter
of 196 millimetres, or 125 teeth with a diameter of 250 millimetres
break down the kernels, with several different roller diameter and
speed options to choose from. The speed at which corns are cracked
and cobs broken down also depends on the cracker clearance and
condition of the rollers. Breaking down the entire plant ensures
that the microorganisms in the methane production process can work
more effectively. The use of a grinding device also helps to
further increase the fibrosity of the plant matter. The greater the
surface area of the substrate, the greater the area that the
microorganisms have to work on. This is the most important
principle in biogas production. However, as increasing this surface
area generally involves more powerful harvesters and higher fuel
consumption, operators need to achieve a balance: chop length
should be as short as necessary, but as long as possible.
21. 21 4 mm 5 mm 7 mm 10 mm Throughput Fuel consumption JAGUAR
The benefits of data capture. Accurate documentation is essential
if plant operators wish to apply for EU funding. Even at the
harvesting stage, biogas plant suppliers must be able to provide
information on energy yield for each crop and each field. With the
JAGUAR, this couldnt be easier. The harvester is fitted with a
CLAAS QUANTIMETER yield measurement system that records all data
relating to harvest quantities. Using information from the prepress
roller deflector and intake speed, the volumetric flow rate is
calculated. For the new JAGUAR 900 Series, the dry matter content
can also be established. A DM sensor on the discharge chute
identifies the DM content of the harvest, based on its
transportability and temperature. This data is then included in the
QUANTIMETER calculations, increasing the accuracy of the yield
data. If operators need to use this data in further calculations,
the JAGUAR can be fitted with a task management solution. The
AGRO-MAP JOB program is installed on a PC in the office, where
customer master data is entered. This is then transferred to the
forage harvester on a Compact Flash memory card. Data from the
harvester is stored on the card for each job that has been created,
and can be transferred back to the main computer in the same way.
This makes the whole data management and invoicing process
incredibly simple. JAGUAR Fuel consumption and throughput for
different chop lengths Source: CLAAS with FH Triesdorf measurements
2006/07
22. 22 Practicality and settings. The CEBIS terminal lets the
operator modify all machine settings, and records performance and
harvest data. This information allows operators to see, for
example, that the JAGUAR is most economical in other words, it
delivers the best balance of performance and fuel efficiency when
running at 1,800 rpm. Maintenance information such as the condition
of knives and sharpening stones is also provided, ensuring
servicing arrangements can be made in good time. There is a 270
litre tank for silage additives, and concentrates can also be used
if desired. These are sprayed directly into the crop as it passes
out of the discharge chute. The amount of additive used is measured
and logged by the CEBIS system. The JAGUAR is the ideal machine for
long days in the field. Additional features such as the SPOUT PILOT
lighten the operators workload considerably, ensuring the spout
flap is always positioned right in the middle of the trailer it is
delivering the forage into. And the TELE CAM camera allows both
drivers to see how full the trailer is. Powerful attachments. The
cultivation of special maize varieties for biogas means new maize
attachments are required. The power output of the forage harvester
must be adjusted to suit the working width and potential output of
the maize header. The ORBIS maize header from CLAAS has been
further improved so that working widths of eight, 10 or 12 rows (9
metres) at a time are possible. High flexibility is required if
good results are to be obtained when harvesting rows of varying
widths. This is why the knife and transport discs of the ORBIS are
placed very close to each other, offering a flat cut and allowing
crops in narrow rows to be harvested effortlessly. The ORBIS has a
modular design, ensuring that the crop enters and leaves the header
in straight lines a prerequisite for a precise chop. Highly
efficient drive trains mean that power requirements and thus fuel
consumption are extremely low. The high starting torques of ORBIS
corn headers mean they can be switched on at full power.
Hard-wearing materials are employed in the knife discs and
replaceable crop flow components, resulting in lower long-term
maintenance costs. The quality of a job can often be seen in the
stubble left standing in the field. This should be as fibrous as
possible, so that it decomposes faster. This also has an important
benefit in terms of corn borers, as it significantly restricts the
development of the larvae population.
23. 23 More flexibility with the JAGUAR. CLAAS offers a range
of different attachments that further increase the capabilities of
the JAGUAR. Whole-crop silage is becoming evermore popular as a
cosubstrate in biogas plants, and the DIRECT DISC has been designed
specially for cereal, legume, intertillage, forage rye and Sudan
grass crops. It cuts directly, mowing and then chopping. There is
also no contact between the ground and the swath, ensuring the
forage is not dirtied unnecessarily it is extremely important that
sand particles do not find their way into biogas plants. The DIRECT
DISC has a working width of 5.20 or 6.10 metres, and features a
suspended frame that allows it to adapt automatically to the
terrain. The CONTOUR system in the JAGUAR and the adjustable
cutting height mean that stubble is always even. The JAGUAR can
also be fitted with a corn husker so that the energy content of the
silage can be increased by adding ground ear maize. Here, the cobs
are harvested with the spindles and husks, as well as around 15 %
of the remaining plant. This provides a more concentrated raw
material for the biogas plant. Ground ear maize is added in small,
precisely controlled quantities, so that the optimum gas level is
always maintained, making it a genuine alternative to CCM.
Harvesting is carried out with the six or eight-row CLAAS CONSPEED.
Various grinding devices enable the JAGUAR to greatly increase
plant disintegration. The heavy duty CRACKER is responsible for
breaking down the individual grains, and can also be modified to
allow revolution differences that are up to 60 % greater.
JAGUAR
24. 24 Broadly speaking, there are three ways of harvesting
grass and similar forage crops for use in biogas production: 1.
Direct cutting by a forage harvester 2. Traditional mowing,
spreading, raking and gathering 3. Combined mowing/swathing For an
optimum gas yield and cost-effective operation of the biogas plant,
biogas grass silage must fulfil the general requirements of any
good-quality silage. Even a good crop can make poor silage if the
correct process is not followed. Green fodder crops have very high
energy yields per hectare, and it is vital that this energy content
is preserved in the ensiling process. The most common problem with
silage quality is excessive crude ash content, i.e. impurities in
the silage, generally as a result of poor field maintenance, poor
sowing practices or contamination during the harvesting process.
Harvesting grass silage for biogas production. Maize silage is not
the only substrate that can be used in biogas production. In many
regions, grass is more readily available, and using it may make
sense from the point of view of crop rotation and use of left-over
growing space. However, the criteria for good biogas grass silage
are somewhat different to silage for use as fodder. Where silage is
used as cattle feed, taste plays a role, and the grass has to be
allowed to wilt until dry- matter content is 35% for optimum
digestion by the animals, but with biogas silage these
considerations are irrelevant. For this reason, biogas grass silage
can generally be damper than cattle feed silage. That said, it must
be remembered that undesirable silage effluent may form if
dry-matter content is not at least 28%. Source: Forschungszentrum
Karlsruhe GmbH Table 1: biogas and electricity yields from grass
silage Grass silage Maize silage No. of harvests/year 2 2 3 (high
yield) 4 Net yield t DM/yr 5.75 7.3 9.0 9.0 13.5 Average DM content
% 89 89 89 89 94 Biogas yield m3 /t DM 540 560 560 580 620 Methane
content % 53 53 53 53 54 Electricity yield kWh/t TS 866 898 898 930
1,070 (effectiveness CHP 34%) kWh/ha 4,980 6,511 8,083 8,372
14,445
25. 25 PROFILINE To maximize gas yields, it is important to
carefully evaluate the different harvesting methods and choose the
most appropriate solution: Forage harvesting. For: Single process
Minimal number of passes Minimal forage contamination, forage does
not come into contact with ground Against: Wilting is not possible
Special equipment required Combined mowing/swathing. For: Separate
raking stage eliminated No additional movement of grass Against:
Dirt is raked together with grass Insufficient swath for chopper
increased harvesting costs Wilting is not possible effluent
formation more likely Special equipment required Traditional
process: mowing/spreading. For: Rapid wilting: DM content 28 %
prevents effluent formation Minimal contamination No special
equipment required Against: Multi-stage process
26. 26 More careful sowing of green forage crops. If the field
is rolled at the time the seed is sown, modern mowing equipment
does not pick up any dirt. Provided the stubble is high enough,
rakes and tedders can be used without any problem. Optimizing
process efficiency. Recent technological advances mean that modern
harvesting machinery can largely avoid the risk of dirt
contamination during harvesting, significantly reducing the crude
ash content of the forage. Example 1: ACTIVE FLOAT mowing
technology The contact pressure of the mowing blades can be
adjusted to the ground clearance, cut height and vehicle speed to
effectively prevent it from touching the ground or becoming caught
in the soil. Example 2: GRASS CARE suspension on the LINER rake The
combination of a floating rotor and a tandem axle ensures smoother
running of the tines and prevents grounding. Example 3: hydraulic
height adjustment in the LINER. With large rotor diameters, even
more precise control of tine is necessary to avoid dirt
contamination. The new hydraulic height adjustment system on all
larger CLAAS swathers is particularly useful when working with
green forage crops or on uneven ground. Summary. When making grass
silage for biogas production, the conventional
mowing/spreading/raking process is generally advisable, making full
use of the latest technology. This prevents effluent formation and
dirt contamination while keeping costs to a minimum. The use of
combined mower/swathers and direct cutting process is of
questionable benefit.
27. 27 Tractor design Versatility is the watchword for todays
tractors. A quick look at machinery usage patterns, especially with
contractors, shows that these days, tractors spend up to 70 % of
their time possibly even more on transportation and power take-off
work. The increase in the number and size of biogas plants is a
factor in this trend. As a result, the last few years have seen an
increase in popularity of compact machines with high power outputs.
Delivering greater fuel economy. CLAAS aims to build tractors that
meet and exceed users expectations in terms of both design and
technology. Vehicles today must deliver plenty of power while being
compact in size and as low in weight as possible. At the same time,
there is now a greater focus than ever on fuel consumption.
Harvesting, logistics and more.
28. 28 The AXION and biogas plants. Combining these
characteristics was a priority when it came to the design of the
AXION range. Outputs range from 163 to 260 horsepower (measured
according to the ECE-R-24 standard), and all models are designed to
deliver more power than their direct competitors in the
200-horsepower class. The AXION is available with a choice of
HEXASHIFT automatic powershift or CMATIC continuously variable
transmission, offering benefits both on the road and in the field.
The AXION and transportation. Very long wheelbase for improved
stability and excellent weight distribution Advanced engines offer
high outputs with low fuel consumption Top speeds of 40 and 50
kilometres per hour are achieved with reduced engine revs, further
improving fuel economy The AXION is available with a wide choice of
options, such as the CEBIS operating terminal for maximum comfort,
and the CIS cabin for ease of operation Front axle suspension and a
large cab with HGV- quality suspension fitted as standard Vehicles
fitted with boost technology are at a significant advantage if they
are regularly driven on the road. The idea is to increase output
when and only when the strain on the engine is high, without
increasing the weight of the vehicle. The feature is a real plus in
mid-range to high-end tractors. Up to 260 horsepower with boost 52
% 48 % Weight-to-power ratio as low as 33 kg/hp (45 kg/kW)
29. 29 Tractor design There are already many boost systems on
the market that offer extra power to the engine from speeds of
around 1315 km/h, and others that cut in at around 20 km/h.
However, these systems are only of use when transporting loads on
the road. CLAAS has developed a new and extremely practical boost
system for AXION machines with the HEXASHIFT gearbox, as well as
for the ARION 540 and ARION 640. The electronics of the CPM (CLAAS
POWER MANAGEMENT) system deliver the additional output from speeds
of around 6 km/h and above (from the C1 gear ratio), meaning AXION
drivers benefit from the extra power for more than 80% of the time
the machine is in use. Furthermore, the boost (up to an additional
35 horsepower) is available in six increments, so only as much
extra power is delivered as is actually required. This solution
ensures fuel consumption is kept to a minimum. This unique solution
offering additional power at lower speeds gives the AXION range
more flexibility. The large AXION 850, for instance, has a
weight-to-power ration of an impressive 35 kg/hp, for exceptionally
dynamic performance. User benefits. A further plus for the user is
that the cabin environment will always be familiar. Armrest
position and cabin layout are essentially the same across the ARION
and AXION ranges, and the controls are identical irrespective of
whether a CMATIC continuously variable transmission or power shift
transmission is fitted. Their high-tech engines and ultra-efficient
drive trains mean the ARION and AXION are among the most powerful
and economical tractors on the market. This has been proven in a
range of independent tests by bodies such as the German
Agricultural Society, and experienced in the field by countless
farmers.
30. 30 Giving biogas plants more: the XERION. Silage
compression. The XERION is equally impressive as a powerful earth-
mover as it is in everyday farming roles. It is the versatility of
the 379-horsepower XERION 3800 and the 335- horsepower XERION 3300
that makes them such valuable pieces of machinery. The XERION can
carry out a range of tasks at both pre and post-fermentation stages
of biogas production, performing tillage and sowing work in maize
fields, and spreading and working in the fermentation residue. The
weight of the XERION is distributed across four wheels of equal
size, which along with its excellent transmission and crab steering
system, makes the vehicle perfect for moving, spreading and
compacting silage in a minimum of time. As a packing tractor, the
XERION can replace two standard large tractors, cutting staff costs
and making the work at the silo simpler to manage. The crab
steering system is a major advantage here, as it enables offset
compressing. With the right ballast, the individual wheel loads can
be as high as 4.5 or even 7.5 tonnes.
31. 31 Better than a wheel loader. While a wheel loader is
capable of pushing material up to the top of a heap, its torque
converter means that it can only do so at higher revs and that
means increased fuel consumption. By contrast, the XERION usually
runs at 1,200 to 1,300 rpm for silage compression, and at between
1,600 and 1,700 rpm when pushing heavy loads. The performance of
the XERION is reflected in excellent silage compression. This is
immediately obvious to any operator using a shear grab to remove
the silage at a later date wherever the XERION has packed the
material, the machine has to exert far more pressure to cut through
it. XERION At the same time, fuel consumption remains surprisingly
low, as the efficiency of its transmission means that the XERION
can push large quantities of silage uphill at low revs. With a
five-metre blade, it can push the contents of an HW 80 trailer onto
the silage heap in one go, and requires just two or three goes to
add the contents of a 43-cubic metre trailer. When driving
downhill, its crab steering system allows the tractor to compress a
three- metre strip at a time. The XERION pushes and compresses
silage most effectively in reverse gear. The pivoting cabin offers
drivers a complete view of the blade, enabling precise control. A
further advantage of the crab steering system is the fact that it
lets the tractor get closer to the edge of the heap, and it also
increases stability. This is what users have to say about the
compression performance of the XERION 3800 with pushing blade and
additional 20-tonne weight: As long as the transport tractors are
able to dump their loads on the top of the heap, the XERION 3800
can spread and compress the 200 to 250-tonne hourly output of a
JAGUAR 970 all on its own. A second tractor is only necessary when
the heap is so high that the silage has to be pushed up to the
top.
32. 32 The XERION comes in a variety of high-performance
variants for effective manure spreading. Both the TRAC VC with
pivoting cabin and a mounted tank with a capacity of up to 15 cubic
metres, and the SADDLE TRAC with mounted or saddle tanks and a
capacity of up to 25 cubic metres, are particularly powerful and
can cover large areas extremely quickly. The versatility of the
XERION makes it hugely attractive it can cover more ground more
economically than other self- propelled slurry spreaders, thanks in
part to its speed of 50 km/h on the road. The practice of working
liquid manure directly into the soil is becoming increasingly
widespread, so as to minimize the evaporation of nutrients. The
enormous haulage capacity of the XERION is a significant factor
here. Its powerful engine (379 horsepower in the XERION 3800, 335
in the XERION 3300), four equal sized wheels, and optimum weight
distribution ensure it can tow large trailers and saddle tanks
effortlessly at the speeds required, even when a tillage implement
is fitted. Spreading fermentation residue with a minimum of fuel.
As nitrogen and phosphate prices have rocketed over the last few
years, liquid manure has become a valuable commodity. The
nutritional value of fermentation substrate is already more than 10
euros per cubic metre but only when the fermentation residue is
spread at the correct time, in the correct quantities and in the
correct way.
33. 33 XERION Benefits of the XERION for substrate spreading.
Ability to work as a self-propelled vehicle Capacities of up to 15
cubic metres with mounted tanks and up to 26 cubic metres with
saddle tanks Full frame construction offers greater load bearing
capacity (up to 36 tonnes for intra-site use) Improved traction
Fast, easy tank filling Excellent spreading performance Optional
power hydraulics (spreading capacity 235 l/min, output up to 90 kW)
Soil protection. Offset driving with crab steering Four large tyres
with a greater footprint than standard tractors Optimum weight
distribution means fields can be driven on in wetter conditions Low
slippage Four-wheel steering ensures rear wheels exactly follow the
front ones An alternative to the use of trailer and saddle tanks is
offered by a mounted tank (up to 15 cubic metres) on the XERION
SADDLE TRAC or TRAC VC (with pivoted cabin). This turns the XERION
into a self-propelled slurry spreader but one with the advantage
that it can also be employed for a host of other jobs. Swan-necked
slurry tankers have also established themselves as viable
alternatives to traditional trailed tankers of late. The long neck
ensures that the seven-tonne tongue weight of the trailer is evenly
distributed between the two axles of the XERION. The optional power
hydraulics for the XERION offers particular benefits for slurry
spreading. With this system, hydraulic motors on the spreading tank
can run off very low engine revs, meaning the engine can run at low
rpm even while spreading, thereby saving fuel.
34. 34 SCORPION the telescopic loader from CLAAS. The perfect
machine for an incredible variety of everyday farming tasks all
year round, the CLAAS SCORPION range was first launched in 2005.
Customers can choose between four different models, two engines
(with out- puts of 88 and 103 kilowatts measured according to ISO
9249 TIER III), a telescopic arm lifting height of 7.10 or 8.95
metres, and a lifting capacity of 3.3 or 4.4 tonnes. Compact and
manoeuvrable (with four-wheel steering, the turning circle
including the wheels is just 3.6 metres, or 3.7 metres for the
9040), the SCORPION offers a spacious, comfortable cab, with plenty
of space for even the largest of drivers. The single-pane front
windscreen with panoramic windows all-round offers 360-degree
sightlines. The low centre of gravity means the SCORPION is
exceptionally stable, and the new continuously variable
VARIPOWER/VARIPOWER PLUS transmission automatically adjusts engine
torque to the desired speed (fully variable between 0 and 40 km/h).
The telescopic arm is controlled using the right hand via an
intuitive joystick, with the left hand remaining on the steering
wheel at all times for safe driving. Two hydraulic systems are also
available for the SCORPION: A constant current hydraulic system
(110 litres, 210 bar) for the 7030 and smaller 7040 models A
load-sensing system (150 litres, 250 bar) for the large 7040 model
and the 7045 and 9040 models The power and hill-climbing ability of
the SCORPION make it the perfect complement to the XERION for
silage work.
35. 35 Even the 110-litre hydraulics can carry out more than
one telescopic function at the same time, thanks to the use of
load-sensing valves. As would be expected, the 150-litre
load-sensing version is even faster and more efficient, and offers
excellent performance at low revs. Switchable boom suspension (with
an automatic function at speeds above 7 km/h) and hydraulic
cushioning in the telescopic arm are fitted as standard, reducing
the strain on both the machine and its operator. Another unique
feature of the SCORPION is the bearing and side guidance of the
telescopic arm in the chassis when it is loading in the lower
position. This allows the forces generated to be absorbed centrally
by the chassis, significantly reducing the load on the main bearing
of the telescopic arm, and so increasing the lifespan of the
machine. It goes without saying that the SCORPION can be fitted
with a hydraulic lock for the front attachment. A reverse fan is
also available. This is activated at the touch of a button, and
works even while the machine is running at full revs something that
is not always the case on competitor models. What is more, CLAAS
has designed a new version of the drive system specifically for use
in biogas plants. The 9040 and 7040 models are also available with
a 30-km/h variant of the VARIPOWER system, which pulls just as hard
as the 40-km/h VARIPOWER PLUS. This means that customers can cut
purchasing costs by opting for a lower top speed of 30 km/h,
without sacrificing performance. The 30 km/h top speed can be
achieved even when four-wheel steering is fitted, for maximum
productivity when manipulating and transporting goods on the owners
own land. SCORPION
36. 36 AGRO-BioGas: all the software a biogas plant needs.
Running a modern biogas plant involves managing a variety of
complex interlinked processes. These days, post-it notes and
back-of-fag-packet calculations are no way to run a business. The
available land and capacity must be used systematically to ensure
the business survives and prospers. AGRO-BioGas from CLAAS
Agrosystems is a complete software solution that helps you manage
every aspect of biogas plant operations. It handles planning,
documentation and performance monitoring for substrate production
and residue spreading, and monitors the level of raw material and
slurry in all silos. Comprehensive functionality. AGRO-BioGas puts
all the information you need at your fingertips. It shows what has
gone and is going into the fermentation tank, and what has been and
will be done and with the fermentation residues. Built-in raw
material management ensures that the plant is run efficiently. Not
only can plant operators see how full all their silos currently
are, but they can also set minimum and maximum levels. The
application will warn you when raw material levels are running low,
and will show you available sources of this material in the local
area so you can react in good time. An integrated approach. Biogas
plant operators swear by this software solution, because all the
information on the system can be accessed at any time from a wide
variety of interfaces. For instance, data on how much field space
is dedicated to substrate cultivation can be taken directly from
the field record system, because AGRO-BioGas supports the AGRO-XML
interface. This gives users a comprehensive overview of what
substrate is available where and in what quality. For easier
planning, transport distances can be displayed, in an intuitive map
form if desired. Delivery notifications and invoicing facilities
are also incorporated into the software. Information on substrate
quantities can be transferred on a memory card from the harvest
logging system of CLAAS forage harvesters and of course all the
field records needed to comply with EU documentation regulations
can be produced automatically. Perfect documentation. AGRO-BioGas
precisely documents the entire production process. The application
can provide an intuitive graphical representation of all material
flows at the touch of a button, making it easy to understand, plan
and coordinate the entire logistical and utilization process in a
way that optimizes methane yield. Constant monitoring of available
storage capacity plays an important part in this. To ensure the
continuous and cost-effective operation of the biogas plant,
AGRO-BioGas can perform a variety Harvest data captured by the
CLAAS JAGUAR can be loaded onto the system from a Compact Flash
card.
37. 37 AGRO-BioGas of useful calculations. For example, it can
tell you if the current stock of raw material is sufficient to
produce a certain amount of methane, or conversely how much methane
can be produced from the existing stock of raw material. And if you
need to work out what mix of raw materials will deliver the most
profitable biogas production given the current circumstances, CLAAS
AGRO-BioGas can tell you that too. A fully mobile solution.
AGRO-NET mobile edition helps farmers to run their field record
system, produce documentation, manage and measure the yield from
each fields, and conduct soil and plant analyses wherever they are.
It shows drivers which field they are currently in, when they
entered it and when they will leave it. All activity is documented
for each field as are interruptions, travel between fields and
transport to and from fields. The system is capable of showing
obstacles, weed patches and fields with areas of riverbank, and
provides precise mapping of where agrochemicals and manure have
been used and where they havent, for automatic compliance with
regulatory requirements governing the use of these substances.
Highly practical. AGRO-BioGas is a comprehensive and professional
solution for biogas plant operators. In addition to documentation
and management functions, it also provides analytics to ensure
profitable operation. The software is also particularly useful for
plant operators who work together in collectives and manage
relationships with large numbers of suppliers. Managing, say, 2,000
hectares of substrate-producing land spread across 1,300 fields is
not a problem which is sure to be good news. For more information,
please contact: CLAAS Agrosystems GmbHCo. KG Bckerkamp 19 33330
Gtersloh Germany contact person: Olaf Wiwedel,
[email protected]
38. 38 CHP = combined heat/power generation. Cosubstrate =
organic material (other than fertilizer) on which the fermentation
process is conducted. Dwell time = the amount of time that the
substrate is in the fermentation tank for. Fermentation tank =
vessel in which the substrate is broken down by microbial action,
releasing the biogas. Also called a digester reactor. Fermentation
residue = the part of the substrate that is not converted into
biogas. Gas yield = the amount of gas released per quantity unit of
substrate. Methane = a colourless, odourless non-toxic gas. Methane
combustion produces carbon dioxide and water. ODM content = the
percentage of a substance that is not accounted for by water and
inorganic material. ODM = organic dry matter. Substrate = the raw
material on which the fermentation process is conducted. Volumetric
loading rate = amount of organic matter added to the fermentation
tank, expressed as a per- centage of total tank volume per unit of
time. WPS = whole-plant silage. Glossary of terms used in biogas
production.
39. 39 Service Further reading on the web.
http://www.duesse.de/znr/index.htm
http://www.landwirtschaftskammer.de/fachangebot/ technik/biogas/
http://www.carmen-ev.de/ http://www.dlg.org/de/index.html
http://www.fnr.de/ http://www.biogas.org/
http://www.solarserver.de/solarmagazin/bioenergie.html http://www.
agrobiogas.eu http://www.gas-plants.com
http://www.industrialgasplants.com http://www.uts-biogas.com