MATERIAŁY DYDAKTYCZNE DO PRZEDMIOTU

Transkrypt

MATERIAŁY DYDAKTYCZNE
DO PRZEDMIOTU
Principles of Waste Treatment
and Management
Wydział Budownictwa i Inżynierii
Środowiska
Opracowała
Maria Żygadło
2011
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al. Tysiąclecia Państwa Polskiego 7, 25-314 Kielce
tel. 41-34-24-209, e-mail: [email protected]
Projekt ,,Politechnika Świętokrzyska – uczelnia na miarę XXI w.’’
Program Operacyjny Kapitał Ludzki Priorytet IV Działanie 4.1, Poddziałanie 4.1.1
na podstawie umowy z Ministerstwem Nauki i Szkolnictwa Wyższego UDA – POKL.04.01.01-00-381/10-00
Contents
CHAPTER 1. BASIC RULES OF WASTE MANAGEMENT ..................................................... 3
1.1.
European waste list ................................................................................................................. 3
1.2.
The hierarchy of waste management ...................................................................................... 3
CHAPTER 2. DISPOSAL ON LANDFILLS...................................................................................
2.1.
Biodegradation mechanism in landfill body ...........................................................................
2.2.
Landfills harmful impact ........................................................................................................
2.3.
The modern sanitary landfill ..................................................................................................
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4
5
7
CHAPTER 3. COMPOSTING......................................................................................................... 11
3.1.
Processes in composting ....................................................................................................... 11
3.2.
Composting plants ................................................................................................................ 12
3.3.
Application of compost ........................................................................................................ 15
CHAPTER 4. ANAEROBIC DIGESTION ...................................................................................
4.1.
Anaerobic processes characteristics .....................................................................................
4.2.
Anaerobic digestion plants ...................................................................................................
4.2.1. Operational processing .........................................................................................................
4.3.
By- processing of products ...................................................................................................
15
15
15
17
18
CHAPTER 5. THERMAL TREATMENT ....................................................................................
5.1.
Thermal processes characteristics ........................................................................................
5.2.
Solid waste incinerators ........................................................................................................
5.3.
Hazardous waste incinerators ...............................................................................................
5.4.
RDF Manufacturing and combustion ...................................................................................
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23
25
29
31
References ........................................................................................................................................ 32
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CHAPTER 1. BASIC RULES OF WASTE MANAGEMENT
1.1. EUROPEAN WASTE LIST (EUROPEAN WASTE CATALOGUE)
The European List of Waste (formerly the European Waste Catalogue) is a catalogue of all waste
types generated in EU. It was issued on 20 December 1993 as the European Waste Catalogue for the
purpose of coordinating the qualification and management with all types of waste. The European
Waste List is based on a system which identifies certain types of waste according to the source
generating the waste (e.g. waste from chemical industry), whereas other wastes are identified
according to the intended use of the product (e.g. wastes from organic substances used as solvents or
waste packaging)[1].
The List applies to all wastes, irrespective of whether they are destined for disposal or for recovery;
it is harmonised. The catalogue is periodically reviewed on the basis of new knowledge. The different
types of waste in the List are fully defined by six-digit code, with two digits for each chapter, subchapter, and waste type. The wastes indicated with an asterisk constitute the hazardous waste. For
example: wastes from shaping and physical and mechanical surface treatment of metals and plastics
are coded by number group 12. In this group ferrous metal dust and particles are coded as 12 01 02,
but machining emulsion and solution containing halogens are coded 12 01 08* [2]. The asterisk means
that the latter ones are included in a hazardous group. The list is used to categorise items and
substances when they become waste.
The members of UE are fulfilling their requirements to integrate the Catalogue into their domestic
legislation.
1.2. THE HIERARCHY OF WASTE MANAGEMENT
In the framework of EC Directive 75/442/EEC on waste, it is stated that the essential objective of
all provisions relating to waste disposal must be the protection of human health and the environment
against harmful effects caused by the different steps of waste management as collection, transport,
treatment, storage and tipping of waste.
The waste strategy including waste hierarchy is elaborated for the communities to take
responsible action on waste. The important purpose of this strategy is putting more emphasis on waste
prevention and reuse and it means it should motivate individuals and businesses to appreciate the
environmental and economic benefits from waste reduction [3].
The hierarchy shall apply as a priority order in line with the Waste Framework Directive
(amendment 2008/98/EC). The hierarchy was illustrated on Figure 1.1.
Fig. 1.1. Municipal solid waste hierarchy [4]
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Reduce, Reuse, Recycle - commonly called the 3 R's - are things that should be done to limit the
amount of waste going to the landfill. Recycling is the collection and separation of materials arising
from waste, and its subsequent processing to producing marketable products.
The benefits from recycling may include: conserving natural resources, saving energy in
production and transport, reducing the risk of pollution, saving costs both in treatment and/or disposal
and in monitoring, reducing the demand for landfill space. A good example of the benefits is that
recycling one glass bottle saves enough electricity to light a 100-watt bulb for 4 hours. Recycling one
aluminum can save enough energy to run a TV for 3 hours.
CHAPTER 2. DISPOSAL ON LANDFILLS
2.1. BIODEGRADATION MECHANISM IN LANDFILL BODY.
Municipal waste, especially the one which has been freshly deposited, contains proportion of
putrescible material - food and paper. Such waste biodegradation, i.e. the action of microbes to break
down the waste into simple organic compounds, such as carboxylic acids, and ultimately to water
carbon dioxide, hydrogen, methane and ammonia, depends on whether or the microbial action is
aerobic or anaerobic.
In the first stage, aerobic bacteria are responsible for degradation of organic matter and produces
CO2, water (H2O) and heat. CO2 may be released as a gas or it absorbs in the H2O to form carbonic
acid (H2CO3), which gives acidity for the leachate generation. A facultative bacterium grows during
the second stage, which can survive in aerobic and anaerobic conditions. Carbohydrates, proteins and
lipids are hydrolyzed to sugars, which are decomposed to CO2, hydrogen (H2), ammonia (NH3) and
organic acids. Organic acids from the second stage convert to acetic acid (CH3COOH), H2 and CO2 by
acetogen microorganisms available in the third stage under anaerobic conditions [5], as well H2S may
be produced by the reduction of sulphate (SO4-2) compounds in the waste by SO4-2 reduction bacteria.
The fourth stage, is considered to be the main stage for LFG production and the longest time stage.
Methanogenic microorganisms under anaerobic conditions degrade the organic acids produced from
the third stage to produce CH4 and CO2, while another microorganism directly converted H2 and CO2
to CH4 and H2O. In the final stage, an aerobic condition occurred with aerobic microorganisms convert
the CH4 generated in the previous stage to CO2 and H2O; as well H2S gas may form in waste with high
concentration of SO4-2. The scheme of organic matter decay in landfill body is presented in figure 2.1.
Fig. 2.1. Processes in landfill body
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Fig. 2.2. Major stages and products of waste degradation in landfills [5]
2.2. LANDFILLS HARMFUL IMPACT
Landfill gas. Landfill gas is a natural by product of the decomposition of solid organic waste and
needs to be managed appropriately. Biochemical methane potential depends mainly on waste
composition [7],[8] and many other parameters (temperature, humidity, oxygen access, etc.) and can
differ from landfill to landfill. The decomposition process is complex but, in general terms, carbon
dioxide and hydrogen are generated early in the decomposition.
As the available oxygen is used up and the waste matures, the anaerobic degradation produces
methane, while the carbon dioxide concentration falls.
The biogas composition is strongly depending the time of degradation (fig. 2.3.).
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Fig. 2.3. The scheme of biogas degradation during the time
Table 2.1. Biogas composition [9]
Landfill gas from a mature waste is composed of 35-60% methane and 35-55% carbon dioxide,
with small amounts of other gases, noticeably the odorous sulfides and mercaptans (table 2.1). The last
group is included in the term “non-methane organic compounds”.
Methane emitted from landfills, released to atmosphere, can explode or it is very active as a self
burning gas. Methane gas is lighter than air, colourless, odourless and tasteless.
Due to the constant production of landfill gas, the increase in pressure within the landfill causes the
gas emissions into the atmosphere. That is the reason of important environmental, hygiene and
security problems in the landfill. Methane forms an explosive mixture with air in the frame of
concentration (5-15%). To remove the risk of explosion and fire in a landfill the venting and flaring
techniques are used to eliminate it.
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Leachate.
The formation and amount of the leachate depends on the compacting method, but the composition
is the result of the type and age of the waste [10], the dilution factor of the water and the extent of the
physical and chemical alterations to the waste, as well as the extent of the biodegradation. That is why
the biogeochemistry of landfill leachate differs from landfill to landfill [11].
The leachate has a high chemical and biochemical oxygen demand and often has polluting
concentrations of ammonia and sulfide, heavy metals, chlorides and other contaminations. Leachate
from municipal waste landfill, in addition to the biodegradable products, can contain such substances
as detergents, pesticides and chlorinated hydrocarbons, which, even if in low concentration, could
have a polluting effect on groundwater if allowed to reach it. Even after dilution of the leachate by
rainwater and surface water, the result is a strongly polluting liquid, which must be prevented from
reaching the groundwater. However, in some cases, the escape of leachate is not unknown and nearby
watercourses can become contaminated. This can create problems of clean-up where the water is
ultimately to be used for human or livestock consumption [12].
Other harmful impact.
When landfill is improperly managed there are many reasons of risk both to human and to the
environment. There are: uncontrolled biogas emission, smoke, odours, escape of leachate, which result
in groundwater contamination and soil contamination. Another effect of negative impact of improperly
landfill operation is landscape degradation and atmosphere bio-contamination (transport of
bioaerosoles). Machinery equipment work on a landfill is the source of sensible noise. Other simple
nuisance problems e.g., dust, vermin, are results of the landfill exploitation at the area.
2.3. THE MODERN SANITARY LANDFILL
Modern landfills are a method of disposing of solid wastes on land without creating nuisances or
hazards to human health of the environment. Directive 1999/31/EU defines landfill as"a site of waste
elimination used for the controlled waste deposit on or in the earth" and it separates three
categories of landfill, which can receive:
 hazardous waste
 municipal and non-hazardous wastes
 inert waste
A modern landfill requires high technical standards, taking in the view both geotechnical
conditions for the location place, geographical area and technical protection of ground water,
surrounding soil and the atmosphere. Operation connected with exploitation procedure on landfill has
an important role in the environmental protection. The necessary exploitation operations there are:
compaction which also helps to reduce their volume, and daily cover with layers of soil [13].
Typically, in the working face, the compacted waste is covered with soil daily (Fig.2.4.).
Fig.2.4. Arrangement of cells in landfill area
Fig.2.5. Compacting the waste by compactor [13]
Alternative daily-cover materials are several sprayed-on foam products and temporary blankets.
Blankets can be lifted into a place with tracked excavators and then removed the following day prior
to waste placement.
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Design and construction.
The design and construction of landfill sites should be carried out in such a manner as to
produce a facility which does not harm humans, animals or the environment. This constrain to
protect the environment against harmful emissions i.e. leachate and landfill gas by careful
construction of a new landfill site including the underlying strata, safe collection systems for
leachate and gas and secure installation for its destruction [14]. A well designed and operated
landfill must prevent groundwater pollution, provide for gas venting or recovery, have a
leachate collection and treatment system [15].
The design of bottom liner system consists of several layers (figure 2.6.): low permeability (clay)
liner, the most desirable natural clay existing in place, and geosynthetics (PEHD). If natural clay is not
accessible at a place, re-compacted clay gained from outsite liner is used.
Depending on geological characteristics of origin stratum of landfill bottom and waste
characteristics (non- hazardous or hazardous), liner system is more or less complicated. When original
stratum in landfill is the natural clay with low permeability coefficient (less the 1. 10-9 m/s) the single
geosynthetic can be used, while the non-hazardous waste is collected. If natural conditions are not so
favourable and need to provide greater protection of the environment, clay and double composite liner
should be installed. In modern landfills liner system is connected with leak detection system, which of
course, involves higher cost of construction. Usually, basing on long-term experiences, the sequence
of layers in the composite liners is like this: clay liner as the base and geomembrane is put above clay.
Fig. 2.6. Layers profile in landfill body
When liner is constructed of clay readily available, generally 60 cm thick, compacted in 15 cm lifts
guarantee enough protection, provide that the permeability of less than 10-6 cm/sec [13]. The upper,
next layer is protective cover consisting of 15-20 cm sand. The role of the sand lining is mechanical
protection of geomembrane and is the bedding for drainage which should be build on.
Drainage layer is filled in with granular media, desirable gravel size of 16 – 32 mm. Drainage layer
can be superseded with geonet or geocomposite drainage net. And geotextile is put between
impermeable lining and drainage layer and waste to avoid mixing the materials in particular layers.
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After the area has been completely filled and covered with a final 2- or 3-ft layer of soil and seeded
with grass, the reclaimed land may be turned into a recreational area such as a park or golf course [15].
Construction of final cover determines the amount of leachate production as reduces storm water
infiltration and determine the cost of laechate treatment, even many years after finishing the
exploitation. The final cover improves landfill gas generation and the ability to make suitable technical
protection including landfill gas collection, provides protection against fire, reduces odours.
Leachate collection system.
The source of the leachate is primarily the water already present in the waste and any water
induced from an external source such as rain water and ground water.
To prevent the movement of leachate beyond the landfill site, an effective impermeable collection
system is necessary. Leachate collection pipes are entrenched near the bottom of the liner layers and
are connected to a main pipe that leads to a leachate holding tank. The pipes (HDPE) are installed on
sand layer, inside drainage layer (fig. 2.7.). To provide the proper function of drainage system, it
should be filled that leachate collection pipes lay above sand layer, in drainage media.
Fig. 2.7.Leachate collection pipes installed inside drainage layer on geomembrane
Biogas collecting system.
Biogas collecting system is represented by vertical extraction wells or by horizontally installed
pipes located in drainage layer built in waste mass, during operating of landfills.
Vertical extraction wells (fig.2.8) can be installed in the beginning stage of landfill construction or
during operation disposal areas.
Wells installed during landfill operating are plunged 75% of the refuse depth. Wells are constructed
of PEHD or PVC, bottom perforated – start 6 meters below the ground surface. Location in the landfill
area at a spacing depending upon “radius of influence” (typical 60 m – 122 m) [13].
Bentonite seal below the head of a well prevents air infiltration (fig. 2.7.). Well heads are equipped
with flow control valve, pressure monitoring port, flow monitoring device, thermometer.
Alternatively, biogas collection can be realised by horizontal drainage (fig. 2.8) but this system is
less effective and can be used on small landfills with elevated leachate levels.
Horizontal collectors should be installed in shallow areas in operational disposal areas at a spacing
of approximately 30 to 100 meters [12].
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Fig. 2.8. Vertical extraction well [13]
Fig 2.9. Horizontal biogas collection system [13]
Methane and carbon dioxide may be monitored using portable detection equipment or the more
accurate and specific on-site gas. Samples of landfill gas may also be taken for laboratory analysis.
Leachate treatment.
Typically the leachates are collected near the landfill in residual tank and then periodically
transported to the nearest sewage treatment plant. The most modern landfill has the on-site treatment
plant for leachate collected in landfill area. However, this solution is expansive and for this reason not
prevalent. Onsite treatment can be either chemical, e.g. precipitation, oxidation/reduction; or physical,
e.g. adsorption; or biological, e.g. aerobic or anaerobic biodegradation.
Landfill gas utilisation.
One beneficial use of landfill gas is to generate heat and power by combustion. Combustion
technologies such as boilers, gas turbines, and internal combustion engines thermally destroy the
compounds in landfill gas. The generators at landfills provide the power for on-site usage. Surplus gas
is flared in the flaring plant in open flares or enclosed flares. Over 98% destruction of organic
compounds is typically achieved [9], [16].
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CHAPTER 3. COMPOSTING
3.1. PROCESSES IN COMPOSTING
The process is based on the decomposition of organic matter by microorganisms in the presence of
oxygen and moisture. Microorganisms break down the waste into carbon dioxide, water vapour and
compost. The result is a stable organic product, which is both hygienic and rich in humus. So, the
combination of oxygen, heat and moisture breaks down the waste and turns it into rich soil/fertilizer.
The final product of composting is sufficiently stable for storage and application to the land without
adverse environmental effects.
Compost is a valuable component for the soil - it helps plants grow by improving drainage and
helping to fight off disease or insect infestations.
The scientific definition of composting is the biological stabilization and decomposition of organic
substrates under oxidic conditions which allow for the development of thermophillic temperature
resulting from biologically produced heat. The process can be expressed by the following equation:
Organic refuse + O2 → compost + CO2 + H2O + heat
(3.1)
The intensity of CO2 emission during incubation of soil-compost mixtures, resulting from the
mineralization of compost organic carbon is used to evaluate compost organic matter stability [17].
The combination of moisture and aeration produce the proper temperature for microbial action.
Oxygen is introduced into the systems by the use of turning or forced draft agitation.
During the intensive composting phase at the beginning of the process, temperature rises and
reaches values from 40oC to 75o C for a period of approximately two weeks [18]. The heat destroys the
pathogenic organisms, weed, and fly larvae. High heat causes rapid decomposition and few unpleasant
odors, which assist the composting process in early stage [19].
Proper composting stabilizes organics, and provides significant drying of a wet substrate. In order
to accomplish these unique aspects the proper moisture content and aeration must be achieved.
This process, which normally takes several months in natural conditions, can be speeded up and
controlled using various techniques.
The role of microorganisms.
The biochemical actions of microbes result in the transformation of the raw organic material of the
compost into humus-like material. There are numerous organisms that work together in the process of
degrading the raw material including slime molds, insects, arthropods, earthworms and bacteria. Some
bacteria function best in aerobic conditions; others in anaerobic conditions. All of these organisms,
along with the humic organic matter form the soil biomass.
Composting organisms require several, equally important, things to work effectively [20], [21]:
 Nitrogen — to grow and reproduce more organisms to oxidize the carbon.
 Oxygen — for oxidizing the carbon, the decomposition process.
 Water
— in the right amounts to maintain activity without causing anaerobic conditions.
Certain ratios of these elements will provide beneficial bacteria with the nutrients to work at a rate
that will heat up the pile.
The most efficient composting occurs with a carbon: nitrogen mix of about 30 to 1. All organics
have both carbon and nitrogen, but the amounts vary widely. Compost piles provide the
microorganisms with a favorable environment for decomposition.
Vermicompost is the product of composting by utilizing various species of worms [22], usually
red wigglers, white worms, and earthworms to create a heterogeneous mixture of decomposing
vegetable or food waste.
Composting worms most often used are Red Wigglers (Eisenia foetida or Eisenia andrei). The
role of worms is the consumption of “fresh compost” and impregnation with their enzymes before
extraction into composting mass. The ready vermicompost is rich in worm’s enzymes and
homogenous in grain size as it’s calibrated to worm’s alimentary tube.
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3.2. COMPOSTING PLANTS
Composting may be realized in two ways:
 one – stage plant: compost which is laid in piles during the whole process, is called aerated
static composting,
 two-stages plant: first step is in -vessel composting facility, and the other – in open air for
maturity attainment
In the aerated static composting (one stage), the waste to be composted is placed in long piles
(fig.3.1.). The windrows are 1-2 m high and 2-5 m wide at the base. The composting is conducted
usually in uncovered piles on natural ventilation with frequent mechanical mixing or throwing of the
piles. Alternatively, the oxygen is provided by mechanical aeration systems using pipes laying inside
the piles (fig. 3.2.). The tunnel systems may be used for better process monitoring (fig. 3.3.)
Fig. 3.1. Aerated static pile of composting material in the open air
Fig.3.2. Pile aeration by throwing (left) and mechanical ventilation system (right)
Fig. 3.3. Composting in tunnel system
Source: Sutco-Polska
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The hotter the pile gets, the more often adding air and water is necessary; the air/water balance is
critical to maintaining high temperatures until the materials are broken down. At the same time, too
much air or water also slows the process, and so too much carbon (or too little nitrogen).
In -vessel composting plant (two stages) (see fig. 3.4.), refuse is firstly put into static or rotary
chamber to speed organics decay under strictly controlled conditions (temperature, moisture, oxygen
amount). The duration of this stage is only several days and then the “fresh compost” is placed in piles
in the open air or in tunnels to achieve the matured form.
The mixed waste is fed to the composting rotating drum units (fig. 3.5) or ventilated static
chambers (fig. 3.6.). Many types of vessel have been used as a reactor in these systems, including
vertical towers, horizontal rectangular and circular tanks, or circular rotating tanks.
Decomposition of food waste by biological bacteria action takes place inside the facilities, while
the moisture amount, temperature, carbon dioxide and oxygen concentration are monitored and
controlled [23], [24].
Fig. 3.4. In-vessel composting scheme
Heat is released during the decomposition process.
The temperature inside the drum or chamber is kept between 55oC and 70oC for pathogens killing
and optimum decomposition. The residence time is shorter in a rotating drum, about 3 days, than in a
static chamber, where the necessary time for organics decay is about 7 to 10 days.
Fig. 3.5. Composting rotating drums
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F.3.6. Ventilated static chambers
Curing.
Before compost may be applied, a curing period of about a few weeks to ensure complete
decomposition must occur [25-27]. The curing can be realised in opened area in piles or tunnel
system. The curing period allows for the decomposition rate to the point where it will not rob the soil
of its nitrogen content. The curing period depends on conditions, like: climate, rains, wind and solar
activities and pH in compost pile. Curing will probably take as little as a few weeks, depending on
compost composition and exterior conditions, but it could take up to 6 months.
The introduction of bulking agents like bark chips, add structural support to the drying compost
allowing for easier aeration by movement of oxygen throughout the mixture.
Finishing.
After curing, in the finishing process the objectionable materials are removed. The mature
composts are sieved by rotating screens (fig.3.7) to remove bulking agents and contaminants. This
process may remove glass, plastic, metals, stones, or other undesirable objects through either further
screening or continued grinding. Bark chips screened out from the mature compost are reused in the
composting process as bulking agents. Compost may be stored in large piles outdoors, into storage
cans, or placed under cover as the final product. Finished compost is of ambient temperature, it is
approximately 1/3 the original volume of material, brownish colour, similar to peat and has an
"earthy" smell.
Regular compost testing and environmental monitoring are conducted to ensure satisfactory
compost quality.
Fig. 3.7.Trommels for compost finishing
Source: SUTCO –Polska
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3.3. APPLICATION OF COMPOST
The compost itself is beneficial for the land in many ways, among others as a soil conditioner, a
fertilizer to add vital humus or humic acids, and as a natural pesticide for soil, but only matured
compost can be used for such purposes. Compost provides an abundance of organic carbon. The way
of maturity assessment of compost is the study of several parameters like: bacteria and enzyme
activities, water –soluble fraction [26], dissolved organic carbon amount [27], stabilization of
biodaegradable carbon amount and C/N ratio, which should be lower than 30.
Limiting parameter of using compost as fertilizer is heavy metal contamination of mixed waste
compost [28], [29]. The acidity of a soil impacts metal solubility, plant uptake and movement and
plant growth.
Fig. 3.8. Matured compost view and soil enrichment
Source: http://www.toronto.ca/compost/pubs.htm
Compost increases soil aggregation and decreases compaction. Compost also increases soil
porosity and consequently aeration. By increasing the water holding capacity of soils, infiltration and
permeability, the compost provides for higher water availability to plants. Because the pH of most
stable compost products ranges from 6.5 to 7.5, the addition of compost can raise or lower a soil's pH
to this level.
Thermophilic temperatures achieved through composting can destroy many plant disease
organisms. Compost products can themselves suppress plant disease organisms. Compost is also
useful in the biofiltration of odorous gases in a vessell composting plant or a digestion plant.
CHAPTER 4. ANAEROBIC DIGESTION
4.1. ANAEROBIC PROCESSES CHARACTERISTICS
Anaerobic digestion (AD) is one alternative for the diversion of waste from landfills, as the UE
Landfill Directive constrains to recover organic materials from the waste stream in Europe[30], [31].
Anaerobic digestion produces biogas, which can be used as a renewable energy. The efficient
bioconversion of waste into biogas provides a renewable energy technology that helps reduce
dependency on fossil fuels, gives the economical and environmental profits [32], [33]. Finally, other
by-product from anaerobic digestion of waste, namely treated sludge and wastewater effluent have
potential uses in agriculteure as compost, soil stabilisers, fertilisers and as matrices for slow release
fertilizers [34], [35].
In Europe the increasing numbers of biogas plants employing anaerobic co digestion food waste
and other putrescible components (yard wastes, sewage sludge, manure and different industrial
organic) as energy sources [36] (fig.4.1.). Organic municipal waste cannot be degraded alone due to
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their characteristics, mainly low solubility, unbalanced carbon to nitrogen (C/N) ratio. This waste
mixed with other complementary wastes becomes suitable for anaerobic co-digestion.
Fig.4.1. General process for an AD co-digestion plant
Source: Monnet F., An introduction to anaerobic Digestion of organic Waste,
Final Report, Remade Scotland, November 2003
Additional benefits of the co-digestion is included: dilution of potential toxic compounds,
improved balance of nutrients synergistic effects of microorganisms, increased load of biodegradable
organic matter, and better biogas yield [37]. Consequently, co-digestion of municipal solid waste and
biosolids may be an attractive alternative for the management of two separate waste streams [38].
Organic matter is constituted of large organic polymers. In order for the bacteria in anaerobic
digesters to access the energy potential of the material, these chains must first be broken down into
their smaller constituent parts like: simple sugars, amino acids, and fatty acids, which exists during
hydrolysis step. These constituent parts or monomers are readily available by other bacteria.
Therefore hydrolysis of these high molecular weight polymeric components is the necessary first step
in anaerobic digestion. Acetate and hydrogen produced in the first stages can be used directly by
methanogens. Other molecules such as volatile fatty acids (VFA’s) with a chain length that is greater
than acetate must first be catabolised into compounds that can be directly utilised by methanogens.
The biological process of acidogenesis consists of further breakdown of the remaining components
by acidogenic (fermentative) bacteria. Here volatile fate acids are created along with ammonia, carbon
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dioxide and hydrogen sulfide as well as other by-products [39]. The third stage anaerobic digestion is
acetogenesis, when simple molecules created through the acidogenesis phase are further digested by
acetogens to produce largely acetic acid as well as carbon dioxide and hydrogen.
Here methanogens utilise the intermediate products of the preceding stages and convert them into
methane, carbon dioxide and water. This step makes up the majority of the biogas emitted from the system.
Methanogenesis is sensitive to both high and low pHs and occurs between pH 6.5 and pH 8 [40].
The remaining, non-digestible material which the microbes cannot feed upon, along with any dead
bacterial remains constitutes the digestate, solid by-product.
A chemical equation for the overall processes outlined above, illustrated on glucose molecule
example, is as follows [31]:
C6H12O6 → 3CO2 + 3CH4
(4.1)
Two stage anaerobic digestion technology assumes the split of main digestion steps. In different
digesters with different temperature mode and retention time. Organic waste accumulation is designed
for 1-2 days of storage capacity and takes place in receiving tank.
At the first stage of fermentation substrate hydrolysis take place under acidogenic bacteria
influence. At second stage elementary organic compounds come through hydrolysis oxidation by
means of heteroacidogenic bacteria with production of acetate, carbon dioxide and free hydrogen. The
other part of organic compounds including acetate forms elementary organic acids. The produced
substances are the feed stock for methanogenic bacteria of the third type. This stage distributes in two
processes, the character of which depends on conditions required by different bacteria type. These two
types of bacteria convert the compound obtained during the first and second stages into methane CH4,
water H2O and carbon dioxide CO2.
Methanogenic bacteria are more particular to living environment to be compared to acidogenic
bacteria. They require complete anaerobic environment and need longer reproduction period. The
speed and scale of anaerobic fermentation depend on bacteria metabolic activity. That is why the
biogas plant technological scheme has hydrolysis reactor with at least 4-5 days retention time using
mechanic mixing and main digester for methanogenic bacteria with 25 days retention time mechanic
and hydraulic mixing system.
4.2. AD plants
Several strategies have been developed for the anaerobic digestion improvement. Chemical,
thermal and mechanical methods have been studied to improve the hydrolytic step of AD, as this first
step is often referred as the limiting one [38]. Anaerobic digestion plant operation by simple typical
layout in blocks was illustrated on figure 4.2.
Fig. 4.2. The simple scheme of anaerobic digestion
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4.2. 1. Operational conditions
A variety of engineered anaerobic reactors to treat food waste are in use in full- scale [38], [41-42]:
- mesophilic (25-45°C) or thermophilic (50-60°C)
- wet (5-15% dry matter in the digester) or dry (over 15% dry matter in the digester)
- continuous flow or batch,
- single, double or multiple digesters,
- vertical tank or horizontal plug flow.
When mesophilic process is realized, neutralization of water suspension from bacteria and viruses
is made in tube sterilization unit during 1 hour at 70o C temperature.
The initial hydrolysis or acidogenesis tanks prior to the methanogenic reactor can provide a buffer
to the rate at which feedstock is added. The central facility in AD plant is digester (fig. 4.3, fig. 4.4.).
Required conditions for digestion are constant temperature of substrate in the range of mesofilic or
thermophilic, and proportional substrate loading within whole digester square. Digester is gas proof
and a hermetically sealed tank made of reinforced concrete.
In two stage system, hydrolysis, acetogenesis and acidogenesis occur within the first reaction
vessel – hydrolysis reactor (for 8-10 days retention time). Hydrolysis reactors may be multiplied for
better organic substances decay. In hydrolysis reactor special temperature conditions are secured, the
humidity is increased and pH level is carefully controlled. The organic material is then heated to the
required operational temperature (either mesophilic or thermophilic) (fig. 4.3.), prior to being pumped
into a methanogenic reactor. From the hydrolysis reactor substrate is supplied in doses to digester that
is a very significant factor for bacterial balance preservation. Substrate contains simple alcohols and
acetate, which are soluble in water.
Fig.4.3.Project Plant Design
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Fig.4.4. Digestion reactor
Fig.4.5.Digesters semblance
Source: Haines R., The BTA Process, Implementing Anaerobic Digestion in Wales Workshop,
Engineering a Cleaner World, 11th November 2008, ENPURE 2008.
The produced substrate is loaded under the pressure to a digester where the final 30 days stage of
waste recycling into biogas and organic fertilizer takes place. Some systems have multiple digesters to
ensure each stage is as efficient as possible. Multiple digesters can give more biogas per unit feedstock
but at a higher capital cost, higher operating cost and greater management requirements.
The digester is continuously stirred and heated to the adequate temperature.. That is why tank
reactor is equipped with wall heating system (Fig. 4.6.). In order to prevent heat losses the outer side
of digesters walls are insulated.
Fig.4.6. The view of wall heating system and mixing system inside the digester
Fot. Anlagen- und Apparatebau Lüthe GmbH(left); WELtec BioPower GmbH (right);
Grafik: Armatec FTSArmaturen GmbH & Co. KG;
Source: Poradnik otrzymywanie i wykorzystywania biogazu“,
publ. by Fachagentur für Nachwachsende Rohstoffe e.V., 2005
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Vertical tanks represented in DRANCO technology (fig.4.7.) are simple and cheaper to operate,
but the feedstock may not reside in the digester for the optimum period of time. Horizontal tanks (Fig
4.8, 4.9.) are more expensive to build and operate, but the feedstock will neither leave the digester too
early nor stay in it for an uneconomically long period [43].
Fig.4.7. Vertical digester in dry system in DRANCO technology
Source: De Baere L., ORGANIC WASTE SYSTEMS: TRUE ALL-ROUNDER IN ANAEROBIC
DIGESTION OF SOLID AND SEMI-SOLID ORGANICS,
Implementing the anaerobic dogestionin Wales,
Cardiff, 11 November, 2008.
Fig.4.8. Horizontal digesters in dry system in KOMPOGAS technology
Source: Martin A., kompogas webside, www.kompogas ch/en/Downloads/Downloads.html
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Fig.4.9. KOMPOGAS dry technology scheme
Source: Schu K., Waste Fermentation and Sand – no Problem?, 2 nd Int. Symp.,
MBT 2007, 22-24 May, Hanover, Germany; www.biower.com
The best system design for each real plant should be determined by what feedstocks are available,
what output is wanted to maximise (e.g. is the goal energy production or waste mitigation), space and
infrastructure.
Pre-processing.
Feedstock should be pre-treated before being directed into the digester. Pre-treatment results in
better methanization level. In the anaerobic digestion plant, the organic portion of the waste is
separated to remove plastic, glass and metals and then placed in a sealed reactor. After sorting facility
organic wastes are transported to biogas plant and loaded to mechanical crashing unit, where organic
and non organic compounds are crashed. Organic grinded material mixed with water is transferred to
suspension. In special tanks non organic materials detachment that have density lower than water is
performed with the help of hydraulic sedimentation (Fig.4.10).
Fig 4.10. Scheme of wet process in BTA technology; the step of ballast removal is distinguished
Source: Blischke J., Anaerobic Digestion of Organic Solid Waste,
AECOM Workschop, PORS 22-24 September 2009.,
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Fig.4.11. Pre-processing in preparation tank (wet system)
Source: Schu K. Waste fermentation and sand – no problem?, Second International Symphosium,
MBT 2007, 22-24 May, 2007, Hannover, Germany.
Inorganic light parts with density less than 800 kg/m3 come to upper layer and are removed by a
special device (Fig.4.11.).
4.3. By-products processing
The gas is normally stored on top of the digester in an inflatable gas bubble or extracted and stored
next to the facility in a gas holder (Fig. 4.12). Biogas accumulated in outer bag gas holders is made of
strong and tensile material. Before utilisation biogas should be treated to remove the moisture,
corrosive sulfides and ballast gas as CO2.
Fig.4.12. Biogas holders
Digested biomass is directed to a separation unit. Treated substrate after biogas plant is directed to
the separation unit. Mechanical separation unit (Fig. 4.13.) detaches digested biomass to solid and
liquid fertilizer. Bio-fertilizer can be directed to packing and granulation line.
Fig.4.13. By-product processing(left) and the view
of anaerobic digestate (right)
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Gas extraction and utilisation.
An anaerobic digestion plant produces three outputs, biogas, digestate and water. They can be
further processed or utilised to produce secondary outputs. Because the biogas recapture among
biological treatment anaerobic digestion is frequently the most cost-effective due to the high energy
recovery linked to the process and its limited environmental impact [44]. Typically, 1 tonne of organic
municipal solid waste produce in the range of 100- 200 m3 of biogas. The energetic potential depends
on methane content.
The methane in biogas can be burned to produce both heat and electricity, usually with a
reciprocating engine or microturbine often in a cogeneration arrangement where the electricity and
waste heat generated are used to warm the digesters or to heat buildings. Excess electricity can be sold
to suppliers or put into the local grid. Indicative energy outputs per m3 of biogas are approximately 4.7
kWh electricity and 2.5 kWh heat. The combined production of electricity and heat is highly desirable
because it reduces the amount of carbon dioxide released into the atmosphere.
Table 4.1. Composition of biogas, natural gas and landfill gas
Source: Monnet F., An introduction to anaerobic Digestion of organic Waste, Final Report,
Remade Scotland, November 2003
Digestate.
The digested organic matter resulting from the anaerobic digestion process is usually called
digestate. The digestate is stored and can be applied straight to a land or it can be separated to produce
fibre and liquor.
Wastewater.
The final output from anaerobic digestion systems is water. This water originates both from the
moisture content of the original waste that was treated but also includes water produced during the
microbial reactions in the digestion systems. This water may be released from the dewatering of the
digestate or may be implicitly separate from the digestate. Usually, wastewater is recycled in AD plant
and excessive amount is treated.
CHAPTER 5. THERMAL TREATMENT
5.1. THERMAL PROCESSES CHARACTERISTICS
Incineration is the controlled combustion of waste originating from municipal, commercial and
industrial sources in order to destroy it or transform it into less hazardous material.
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Basing on the method characteristics, thermal waste treatment can be realised as:
 Combustion
 Pyrolysis
 Gasification
The above methods are differentiated by the amount of air excess comparing to stoichiometry
request. The parameter expressing this ratio is called Lambda parameter, which is varied depending
on the process type: in pyrolysis it is equal to zero or very close to zero, in gasification it is less than 1
value, and in combustion it is higher than 1 value. The combustion processes need to be led in
considerable excess of air, while pyrolysis consists of thermal decomposition in the absence of
oxygen. If air is omitted, waste is pyrolysed to produce a fuel which is then burned to produce energy.
Pyrolysis is the precursor to gasification, and takes place as a part of both gasification and
combustion. There are different conditions that should be controlled at each of the processes (Table 5.1).
Table 5.1. Typical operation parameters and reaction products of thermal waste treatment processes [45]
source: www.ieabioenrgytask36org/publications/2007
As it is shown in table 5.1., pyrolysis is the thermal decomposition or fragmentation of organic
matter in a strictly inert atmosphere.
The reaction starts at 200 - 250°C and is, in this region, often called degassing. For the processes
running at high temperature the terms carbonisation or coking are also common. The highest
temperature in these processes is in the order of 700°C [45].
Products of pyrolysis are:
 gases, predominantly CO, H2 and short chain hydrocarbons;
 pyrolysis oil comprising low volatile hydrocarbons up to tars;
 solids, which are a mixture of coke and inert ashes.
Gasification is the partial oxidation of organic substances using oxygen, air, or steam as oxidising
agents. The reaction product, called synthesis gas (or syngas), consists mainly of H2 and CO with
small amounts of methane and other short chain hydrocarbons [46], [47].. The reaction is endothermic.
The solid residues are inert ashes or slags and fly ashes [48].
A gasification system may be closely integrated with a combined cycle gas turbine for electricity
generation (IGCC - integrated gasification combined cycle).The following simplified chemical
conversion formulas describe the basic gasification process [49]:
C(s) + H2O = CO + H2; Heterogeneous water gas shift reaction — endothermic
C(s) + CO2 = 2CO; Boudouard equilibrium — endothermic
C(s) + 2H2 = CH4; Hydrogenating gasification — exothermic
CH4 + H2O = CO + 3H2; Methane decomposition — endothermic
CO + H2O = CO2 + H2; Water gas shift reaction — exothermic
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Gasification of municipal solid waste is an attractive means to treat with less pollution emission
than other methods of treatment. However the tar is formed in the product gas during MSW
gasification. Tar will result in the shut down of gasification facilities due to blocking and fouling of
downstream application processes (engines and turbines) and thus post-treatment maintenance and
complex cleaning are required. To avoid these problems gasification of MSW by steam is widely
considered because it can decrease the tar content and the novel tar-free catalytic gasification process
using steam as gasification agent is proposed [49].
Combustion is the process by which flammable materials are allowed to burn in the presence of air
or oxygen with the release of heat. The basic process is oxidation, thus the total oxidation of a fuel
exists, predominantly of its organic components, but also of some inorganic ingredients like
elementary sulphur, which goes to acid, harmful SOx.
When the flammable fuel material is a form of biomass the oxidation is of predominantly carbon
(C) and hydrogen (H) in the cellulose, hemicellulose, lignin, and other molecules present to form
carbon dioxide (CO2) and water (H2O).
The process is exothermic with the main energy releasing chemical reactions:
C + ½O2 = CO ΔH = - 110.5 kJ/mol
C + O2 = CO2 ΔH = - 393.5 kJ/mol
Combustion is the simplest method by which biomass can be used for energy, and has been used
for millennia to provide heat. This heat can itself be used in a number of ways:
 Space heating
 Water heating for central or district heating or process heat
 Steam raising for electricity generation or motive force.
5.2. SOLID WASTE INCINERATORS
Municipal solid waste (MSW) is usually combusted in big facilities called incinerators (Fig.5.1.),
with capacity of thousands tons per year. The biggest one is located in Amsterdam with total capacity
of 1,4 mln ton per year.
Combustion is the simplest method by which waste can be used for energy in assistance of the total
oxidation of a fuel, predominantly of its organic components, but also of some inorganic ingredients
like elementary sulphur.
Incinerator – is an installation (fig.5.2.), where wastes are burned to reduce the amount that goes
to the landfill.
Fig. 5.1. The view of modern incineration plants: Maishima, in Japan (on left), Vienna in Austria, (on right);
In the incineration process, waste collection vehicles dump the waste in vast trenches where it is
mixed and transferred to the furnace. Additional fuel can be added to ensure complete combustion.
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The waste is then burnt at temperatures reaching 1000°C, producing steam that turns turbines, which
in their turn produce electricity [14], [50]. The heat produced by waste burning in the furnace is used
to heat buildings and produced electricity may be transferred and sold to Central Electricity Station.
Fixed-bed combustion systems include grate furnaces and underfeed stokers.
Air is always required for typical incineration. The fumes produced in the combustion are treated
by a dry or wet method [51]. Simplified scheme of flue gas cleaning is presented on Figure 5.3.
Ashes and slags may be treated in a special way and can be reused, for example in ceramics [52] or
in civil engineering [53].
Fig.5.2. Typical scheme of incinerator
Fig. 5.3.Flow diagram of a MSW grate incinerator equipped with a roller grate, parallel-flow combustion
chamber, horizontal boiler, wet scrubbing with spray dryer (Offenbach, Germany);
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There are three basic types of incinerators:
 static chamber,
 moving hearth,
 rotary kiln.
The choice of an incinerator depends on factors such as the physical form of the waste, e.g. the
waste may consist of drummed chemicals or disused parts of transformers, or more simply of a
mixture of liquids of different viscosities [14], [45]. There are several types of furnace, where wastes
are combusted [45]: grate furnace, bubbling fluidised bed, circulating fluidised bed.
In reality, combustion is the final stage in the chain of chemical reactions which take place between
the entry of the waste into the combustion chamber at ambient temperature and its final combustion
temperature in the range of 800 to > 1,000°C. The combustible gases produced are burned after
secondary air addition has taken place, usually in a combustion zone separated from the fuel bed.
Fig.5.4. Cross section of grate in furnace in fixed bed incinerator (left) and design of grate(right)
source: HITZ, Hitachi Zose, Municipal Incineration Plant
Fig.5.5.Processes on grate in incinerator furnace
The rotary kiln (fig.5.6.) is the most efficient incinerator that continually brakes the waste by the
rotating drum and the rotational movement enhances the turbulence and hence the mixing of air with
the burning waste. This incinerator is particularly used for destruction of hazardous waste. Such
chemicals as PCBs, PCTs, chlorinated pesticides and halogenated solvents are incinerated in this way.
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An afterburner is frequently used to ensure the complete destruction of toxic combustible gases.
This type of incinerator is the best for ensuring the destruction of infectious waste and for certain
chemicals, e.g. PCBs, where a long residence time is necessary.
Fig. 5.6.The rotary kiln; Source:Von Roll /NOVA, AVG Hamburg, hazardous waste,
incineration plant – Firm offering material.
Within a fluidised bed furnace (fig.5.7.) biomass fuel is burned in a self-mixing suspension of gas
and solid-bed material into which combustion air enters from below. A fluidised bed consists of a
cylindrical vessel with a perforated bottom plate filled with a suspension bed of hot, inert, and granular
material. The bed material is fluidised by air injected through nozzles in the floor of the furnace, and is
usually of about 1.0 mm in diameter; the fluidisation velocity of the air varies between 1.0 and 2.5
m/s. The common bed materials are silica sand and dolomite. The bed material represents 90-98% of
the mixture of fuel and bed material.
Fig. 5.7. Stationary (left) and circulating (right) fluidised bed furnaces
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The intense heat transfer and mixing provides good conditions for a complete combustion with low
excess air demand. The combustion temperature has to be kept low, usually between 800-900°C, in
order to prevent ash sintering in the bed. This can be achieved by internal heat exchanger surfaces, by
flue gas recirculation, or by water injection. Three types fluidised beds have been used for waste
incineration:
 stationary,
 circulating,
 revolving (or internally circulating).
Fluidised bed facilities are preferentially used for RDF (refuse derived fuel) and need several
conditions to be fulfilled [45]:
 Combustion of pre-treated (shredded) waste in a bed of sand (partly with dolomite),
 Waste particle size < 200 mm
 The sand facilitates an efficient heat transfer and is separated from the extracted bed ash and
recycled
 LHV(law heat value) of the fuel can change in wide ranges from < 5 MJ/kg till >20 MJ/kg
5.3. HAZARDOUS WASTE INCINERATION
It is difficult to estimate the risks to human health from the handling of hazardous waste and there
have been very few investigations of parameters such as: toxicity, infection, flammability and
explosivity. The typical incineration process of hazardous substances can emit substances of equal or
greater hazard than the starting material, e.g. chlorinated dioxins and chlorinated furans, which are
extremely toxic to humans, and which come from the incineration of waste containing PCBs or PCTs.
In such cases plasmas reactors are particularly useful for treatment of specific hazardous waste,
like radioactive or hospital. Also electronic or fluorinated waste gases are treated in plasma reactors
[54-58]. Those specially designed incinerators to scope with the destruction of "difficult waste", are
usually operated by private companies, where similarly contaminated wastes may be generated. A
company which produces large quantities of combustible waste may make it more economical to have
its own on-site plasma reactor.
Thermal plasmas are atmospheric-pressure plasmas characterized by temperature about 2000 –
10000 K [56]. Most thermal plasmas are generated by either an electric arc or by a radio-frequency
induction discharge or by microwave discharge. In waste treatment, arc plasmas dominate because
they are relatively insensitive to changes in process conditions [59]. Thermal plasma pyrolysis can be
described as the processes of reacting a carbonaceous solid with limited amount of oxygen at high
temperature to produce gas and solid products. In the highly reactive plasma zone, there is a large
fraction of electrons, ions and excited molecules together with the high energy radiation. When
carbonaceous particles are injected into a plasma, they are heated very rapidly by the plasma. The
volatile matter is realised and crack giving rise to hydrogen and light hydrocarbons such as methane
and acetylene. For example medical waste is pyrolysed into CO, H2, and hydrocarbons when it comes
in contact with the plasma arc. These gases are burned and produce high temperature (around 1200oC).
In the plasma pyrolysis process, the hot gases are quenched from 500oC to 70oC to avoid
recombination reactions of gaseous molecules that inhibit the formation of dioxins and furans [54].
In a properly managed process, the products of incineration are treated safely.
Those installation are rather small, with much lower capacity than MSW incinerators.
Thermal plasma device or plasma torch produces plasma column between two electrodes (Fig.
5.8). Gas cleaning system is following the plasma gasification reactor (fig. 5.9).
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Fig. 5.8. Plasma gasification reactors cross section (left) [59];
(right) Bhasin K.C. Plasma Arc Gasification For Waste Management, internet
Fig. 5.9. Process diagram with plasma gasification [49]
The example of installation for neutralisation of hospital waste in pyrolysis chamber is presented in
figure 5.10. As was presented in figure 5.11, additionally equipment of pyrolysis facility is combustion
chamber of pyrolysis gas. Many researches noted that waste destruction in pyrolysis method by
plasma processing produced useful fuel gases and inert residuals from organic wastes.
Fig. 5.10. Pyrolysis installation for hospital wastes neutralization
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Fig. 5.11. Scheme of the rotary pyrolysis drum for hospital waste treatment;
The principal advantages offered by plasma processing are: high energy densities and high
temperatures characteristics and smaller installation size for a given waste throughput. Additionally,
the processing in plasma method results in lower off-gas flow rates and consequently lower gas
cleaning cost. But relatively high plasma energy requirements (~ 600 kWh/ton) and capital cost of
complex molten bath reactors limited economic feasibility of plasma processes. The use of gasification
technology has made plasma a more economically attractive alternative. Mobile plasma unit for
different types of toxic waste treatment has been developed and constructed [57].
5.4. RDF manufacturing and combustion
Refuse –derived fuel (RDF) is a result of processing solid waste to separate the combustible
fraction from the noncombustibles, such metals, glass and other minerals components [9]. A
processing aiming at obtaining the required features or characteristics, i.e., suitable calorific value and
required technological properties is defined as the conditioning or firefly forming of fuels. Fuels
obtained in such processing are called “formed fuels “and have been the object of high interest in the
last decades, as a new trend in thermal waste treatment [60], [62].
The separation technology allows the production of well defined fractions from heterogeneous
household waste and comparable types of waste. RDF is predominantly composed of paper, plastic,
wood and kitchen wastes and has a higher heat value than untreated MSW, typically of 12.000 to
13.000 kJ/kg. RDF manufacturing process scheme was illustrated on figure 5.12.
Fig.5.12. RDF manufacturing process scheme
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Depending on the desired quantity, composition and calorific value of the remaining RDF, different
classification units may be installed on the overflow.
Further processing of the remaining RDF by a combination of thermal drying, shredding,
palletising, etc., can produce a higher quality secondary fuel appropriate for energy recovery in
specified facilities. Small pellets or fluffy material allow easy transportation, storage and combustible
stability. RDF is sold and used in dedicated RDF boilers or co- incinerated with coal or oil in a multifuel boiler. Efficient use of RDF as an energy resource contributes to recycling strategies.
References:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
Wuttke J., European Waste List, Federal Environmental Agency, http://www.basel.int/centers
European Waste Catalogue and Hazardous Waste List, valid from 1 January 2001, Environmental
Protection Agency,
Defra, Waste Strategy for England, 2007, May, 2007. internet
Susta M.R, Biogas production from municipal solid waste in Havana, Cuba, Workszhop Powergen Asia
2007, Bangkok-Thailand. internet
Williams, P.T., 2005. "Waste Treatment and Disposal", 2nd ed. John Wiley & Sons Ltd, England, ISBN 0470-84912-6, pp. 171-244.
Abushammala M.F.M., Basri N.E.A., Kadhum A. A.H., Review on Landfill Gas Emission to the
Atmosphere, European Journal of Scientific Research, (2009), v. 30, 3, 427-436.
Jokela J.p.Y., Kettunen R.H., Rintala, J.A., Waste Manage.Res., Methane and leachate emission potential
from various fraction of municipal solid waste (MSW), (2002), 20, 424-453.
Owens J.M., Chynoweth D.P., Biochemical methane potential of municipal solid waste componenets,
Wat.Sci.Tech., (1993), 27, 1-4.
Cheremisinof N.P. Handbook of solid waste management and waste minimization, Butterwoth &
Heinemann, An imprint of Elsevier Science, Boston, 2003
Kulikowska D., Klimiuk E., The effect of landfill age on municipal leachate composition, Bioresource
Technology, (2008), 5981-5985.
Christensen T.H., et al, Biogeochemistry of landfill leachate plumes, Applied Geochemistry, (2001), 16,
659-718.
Matejczyk M. et al., Estimation of the environmental risk post by landfills using chemical, microbiological
and ecotoxicological testing of leachates, Chemosfere, (2011), 1017-1023.
Frankiewicz T. Landfill Methane to Markets Workshop, Kraków, Poland, 9 July 2009. internet
Weiner R.F., Matthews R.A., Environmental Engineering, Fourth Edition, Butterworth Heinemann, 2001
Tchobanoglous G., in Salvato, J.A., Nemerov, N.L., Agardy F.J, Environmental Engineering, fifth edition,
Edited ISBN 0-471-41813-7, 2003 John Wiley & Sons, Inc., Hoboken, New Jersey
Papageorgiu A., Barto J.R., Karagiannidis A., Assessment of the greenhouse effect impact of technologies
used for energy recovery from municipal waste: A case study for England, Journal of Environmental
Management, (2009), v.90. 10, 2999-3012.
Bernal M.P., Sanchez-Monedero, M.A., Paredes C., Roing A., Carbon mineralization from organic wastes
at different composting stages during their incubation with soil, Agriculture Ecosystems and Environment,
(1998), 69, 175-189.
Klejment E., Rosiński M., Testing of thermal properties of compost from municipal waste with a view to
using it as a renewable, low temperature heat source, Bioresource Technology, (2008), 99, 8850-8855.
Mao I-Fang, Tsai Chung-Jung et al., Critical components of odours in evaluating the performance of food
waste composting plants, Science of the Total Environment, (2006), v.370, 2-3, 323-329.
Hasen A., Beguith K., et al., Microbial characterization during composting of municipal solid waste,
Bioresource Technology, v. 80, 3, 2001, 217-225.
Vargs –Garcia M.C., Suares-Estrella F., Lopez M.J. Moreno J., Microbial population dynamics and enzyme
activities in composting proceses with different starting materials, Waste Management, (2010), v.30, 5,
771-778.
Nair J., Sekiozoic V., Anda M., Effect of pre-composting on vermicomposting of kitchen waste,
Bioresource Technology, (2006), v.97, 16, 2091-1095.
Kalmdhad A.S.et.al, Rotar drum composting of vegetable waste and tree leaves, Bioresource Technology,
(2009), v. 100, 24, 6442-6450.
32
Biuro Projektu
24. Kanat G., Demir A. et al., Addressing the operational problems in a composting and recycling plant, Waste
Management, (2006), 26, 12, 1384-1391.
25. Sidelko R., Janowska B., Walendzik B., Siebielska I., Two composting phases running in different process
conditions timing relationship, Bioresource Technology, (2010), 101, 6692-6698.
26. Castaldi P., Garau G., Melis P., Maturity assessment of compost from municipal solid waste through the
study of enzyme activities and water –soluble fraction, Waste Management, (2008), v. 28, 3, 534-540.
27. Zmor-Nahum S., Markovitch O.,et,al, Dissolved organic carbon, (DOC) as a parameter of compost
maturity, Soil Biology, and Biochemistry,(2005) v. 37, 11, 2109-2119.
28. Domingo F.L., Nadal M., Domestic waste composting facilities: A review of human health risks,
Environment International, (2009),v. 35, 2, 382-389.
29. Farrell M., Jones D.L., Heavy metal contamination of mixed waste compost: Metal speciation and fate,
Bioresource Technology, (2009), v. 100, 19, 4423-4432.
30. Lewis J.W., Barlaz M.A., Themelis N.J., Ulloa P., Assessment of the state of food waste treatment in the
United States and Canada, Waste Management, (2010).
31. Clarke W.P., Alibardi L., Anaerobic digestion for the treatment of the solid organic waste: what’s hot and
what’s not, Waste Management, (2010), 30, 1761-1762.
32. Morin P. Marcos B., Moresoli Ch., Laflamme C.B., Economic and environmental assessment of energetic
valorization of organic material for municipality in Quebec, Canada, Applied Energy, (2010), 87, 275-283.
33. Poschl M., Ward S., Owende F., Evaluation of energy efficiency of various biogas production and
utilization, Applied Energy, (2010), 87, 3305-3321.
34. Supaphol S., Jenkins S.N., Intomato P., Waite I.S., O’Donnel A., Microbial community dynamics in
mesophilic anaerobic co-digestion, Bioresource Technology, (2011), 102, 4021-4027.
35. Hargreaves, J.C., Adl M.S., Warman, P.R., A review of composted municipal solid waste in agriculture,
Agriculture, Ecosystems and Environment (2008), v. 123, 1-3, 1-14.
36. Lee M., Hidaka T., Tsuno H., Two-phase hyperthermophilic anaerobic co-digestion of waste activated
sludge with kitchen garbage, Journal of Bioscience and Bioengineering, (2009), v. 108, 5, 408-413.
37. Sosnowski P., Wieczorek A., Ledakowicz S., Anaerobic co-digestion of sewage sludge and organic fraction
of municipal solid wastes, Advances In Environmental Research, (2003), 7, 609-616.
38. Strott P.G., McMahon K.D., Mackie R.I., Raskin L., Anaerobic codigestion of municipal solid waste and
biosolids under various mixing conditions, I. Digester performance, Wat.Res. (2001), v. 35, 7, 1804-1816.
39. Dogan E., Dubaev T., Erguder T.H., Demirer G.N., Performance of leaching bed reactor converting the
organic fraction of municipal solid waste to organic acids and alcohols, Chemosphere, (2008), 74, 797-803.
40. Monnet F., An introduction to anaerobic digestion of organic wastes, Final Report, Remade Scotland, 2003,
internet
41. Park Y. J., Hong F., Cheon JiH., Hidaka T., Tsuno H., Comparison of thermophilic Anaerobic Digestion
characteriscs between single –phase and two-phase systems for kitchen garbage treatment, Journal of
Bioscience and Bioengineering, (2008), v.105, 1, 48-54.
42. Angelidaki I., Chen X., Cui J., Kaparaju P., Ellegaard L., Thermophilic anaerobic digestion of source –
sorted organic fraction of household municipal solid waste:star-up procedure for continuously stirred tank
reactor, Water Research, (2006), 40, 2621-2628.
43. Gallert C., Winter J., Biogas production from Biowaste, manure and energy crops, mass and energy
balances, Universitat Karlsruhe (TH), internet
44. Mata-Alvarez J., Mace S., Llabres P., Anaerobic digestion of organic solid wastes. An overview of research
achievements and perspectives, Bioresource Technology, (2000), 74, 3-16.
45. Becidan M., Vehlow J., Howes P.: In: IEA Bioenergy, Task 36, Integrating Energy Recovery into Solid
Waste Management Systems, (2007-2009) End of Task Report,
www.ieabioenrgytask36org/publications/2007
33
Biuro Projektu
46. Rickets B., Hotchkiss R., Livingsto B., Hall M., Technology review of waste /biomass co-gasification
technology, Ichem Fifth European Gasification Conference, 8-10 April 2001, Noordwik, The Netherlands,
internet
47. Choy K.K.H. et al., Process design and feasibility study for small scale MSW gasification, Chemical
Engineering Journal, (2004), vol. 105, 1-2, 31-41.
48. Guan Y., Luo S., Liu S., Xiao B., Cai L., Steam catalytic gasification of municipal solid waste for
producing tar-free fuel gas, Int. J.of Hydrogen Energy, 34, (2009), 9341- 9346.
49. Moutouris A., Voutsas E., Tassios D., Solid waste plasma gasification: Equilibrium model development
and energy analysis, Energy Conversion and Management, (2006), 47, 1723-1737.
50. Poteous A., Energy from waste: A Wholly Acceptable Waste-management Solution, Applied Energy,
(1997), v.58, 4, 177-208.
51. Pschick A., Districk heating & cooling in Vienna, The “Vienna Model”, First Global District Energy
Climate Awards, - Fenwarme Wien, internet
52. Cheeseman C.R., Monteiro de Rocha S.,, Sillars C., Bethanis S., Boccaccini A.R., Ceramic processing of
incinerator bottom ash, Waste Management, (2003), 23, 907-916
53. Saikia N., Shigeru K., Kojima T., Production of cement clinkers from municipal solid waste incineration
(MSWI) fly ash, Waste Management, (2007), 27, 1178-1189.
54. Nema S.K. Ganeshprasad, Plasma pyrolysis of medical waste, Curren Science, v. 83, (2002), 3, 271-278.
55. Dmitriev S.A., Lifanov F.A., Savkin A.Eu., Popkov V.N., Polkanov V.A., et al., Plasma plant for
radioactive waste treatment, WM’01 Conference, February 25- March 1, 2001, Tuscon AZ, internet
56. Tippayawong N., Khongkrapan P., Development of laboratory scale air plasma torch and its application to
electronic waste treatment, Int. J. Environ. Sci. Techn., (2009), 6, (3) 407-414.
57. Mosse A.L., Lozhachnik A.V., Savchenko G.E, Mobile plasma unit for toxic waste destruction, Publ.
Astron. Obs.Belgrade, (2010), 89, 301-305.
58. Sichler P., Buttgenbach S., Baars-Hibbe L., Schrader C., Gericke K-H. A micro plasma reactor for
fluorinated waste gas treatment, Chemical Engineering Journal, (2004), 101, 465-468,.
59. Heberlein J., Murphy A., Thermal plasma waste treatment, J.Phys.D.;Appl.Phys. (2008), 41, 1-20.
60. Wandrasz J.W., Wandrasz A.J., Formed fuels (in Polish), Warszawa, Seidel-Przywecki, 2006.
61. Lach J., Sadowski K., Poskrobko S., Mathematical formalism for blending to obtain fored fuels from waste,
Fuel, (2008), 87, 2677- 2685.
34
Biuro Projektu

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