**2. Municipal solid waste characteristics**

The majority of waste worldwide is currently still being disposed of on landfills without any or proper treatment. The landfills itself are mostly just big deposit sites located in valleys or depressions without any protection of ground water. This means that fast total quantity of

Some developing countries have in recent years successfully introduced material recovery of separately collected fractions and mechanical and biological treatment (MBT) of waste. The

Developed countries have based the waste management on the separate collection of various waste fractions. In most developed countries is in power for over 40 year. The separate collection waste process is long improving process and needs continuous education of all generations, especially youth at school of all grades, from kindergarten to high school. The payment system of waste collection also motivates population to separately collect and

Local,regionalandnationalintegratedwastemanagement conceptis composedofmanyclosely related and connected technical and technological processes. With the aim to establish an environmentally and economically acceptable waste management it is essential for all the technological and logistical steps in the process of waste management to be interlinked and

The MBT technologies are being introduces in regional waste treatment centers for the treatment of residual waste. This minimizes the mass and stabilizes waste before mostly being put directly to landfill. On the other hand this treatment can prepare relatively constant quality waste fraction with good calorific value ready to utilize in standard or advanced waste – to –

The energy utilization of waste is justified in energy and environmental sense and it is obliga‐ tory to fulfill local legislation and in case of Europe also European waste directive demands. [5], [9]. In doing so there must be meeting all legal requirements that define the process of waste incineration or rather called waste to energy (W-t-E) process. [5] Heat generated can be used to

TheyearlyamountofenergycontainedinwastegeneratedbyanaverageEuropeanUnionfamily is such that they would be able hypothetically to entirely heat up low energy house of reasona‐ ble size all season.Incinerationofwaste ina centralizedsystemoflarger capacityis environmen‐

The utilization of energy in waste can be technically achieved with many different technolo‐ gies. As W-t-E plants are rather moderate to big size facilities they produce power and hot water or steam with the energy of waste. Deferent technologies enable distinct approaches for utilization of enthalpy in different thermal machines that are capable to transform this enthalpy

All these processes need to follow strict environmental standards to avoid any negative impacts into the air, water or soil. Thus, the process must be regarded as a whole, not letting

tally, technically and economically feasible, thus a solution for W-t-E at regional level.

produce power (electricity), hot water for heating and cool media for cooling.

any material of energy flow out without environmental considerations.

latter has somewhat reduced emissions of greenhouse gases from waste disposal.

waste ends on landfills.

harmonized.

energy (W-t-E) plants.

discharge fraction in appropriate bins.

278 Advances in Internal Combustion Engines and Fuel Technologies

into mechanical and then into power.

Waste treatment technology, where applied, is nowadays a highly developed and advanced activity with constant and extensive public control. Specially developed combustors for waste incineration are inevitably needed in every modern and civilized society.

Nowadays, bed combustion on grate is the most common way to incinerate municipal solid waste and generate electrical power and heat. [2] The combustion in these plants is very specific due to the characteristics of municipal solid waste which depends on collection, pretreatment, season of the year, etc. [13] The goal of every technology producer on one side and the operators on the other side is the optimal thermal conversion of calorific energy of waste into electrical power and heat with minimal emission of the pollutants to the environment.

A considerable decrease in amounts of municipal waste from commerce is expected due to the regulation on waste packaging material in developed countries and the aim to lower the costs in commerce in general. At the same time an increase in the quantity if household waste is expected. The fact is that an increase in the gross domestic product and peoples' living standard is consequentially shown also as increase in waste quantities.

Structure of the waste and its components are very much a factor of nation development and wealth. In Table 1 is presented the average structure of the municipal solid waste and com‐ parison to other developed countries show that the structure is very similar. In developing countries the average structure has less packaging material (paper, plastic) thus has in fresh state lower calorific value as waste from developed countries.

Structure of the waste (Table 1) varies depending on season and weather conditions. It also depends on the contribution region (rural, urban,...), which influences the moisture and biodegradable waste share.

The average waste material utilized in W-t-E process is composed of materials that add up to the calorific value of the waste. This waste stream is usually called "refuse derived fuel" – in abbreviation RDF, and is made up of paper, cardboard, plastic, foils, textile and wood. The RDF is initially processed in the MBT plant from the municipal solid waste. Table 2 shows the results of the investigated materials included in the RDF.


**Table 1.** Average structure of municipal solid waste in Germany [3]


The primary task of MBT is mechanical waste preparation and aerobic microbiologic waste treatment with the aim to biologically stabilize waste and dry it. Mechanical separation of combustible and incombustible part of waste follows. The combustible part usually has heating

Combustion of Municipal Solid Waste for Power Production

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The completely integrated waste management concept should be developed, build and in operation at regional level or really big cities for processing municipal solid waste. Such system is in economic terms effective if developed for over 200.000 people producing at least about 100.000 t/year of municipal solid waste. If developed for special conditions like mountainous regions, less populated areas,… these figures can be half or third of above mentioned because logistics cost and its environmental influence would make it worse to generate high waste

The integrated system should be based on law enforced separated collection, composting, recycling, MBT of residual waste, W-t-E of combustible fraction and disposal of inert fraction from MBT. Into the process of thermal treatment also sewage sludge from regional waste water treatment plants can be induced. Generally no special drying is needed for sewage sludge only mechanical dewatering process is utilized to squeeze the water out to get the sewage with

The operation of the integrated waste management system must realize multiple objectives related to environmental protection. The waste reuse is increased and its treatment is ensured. The amount of emissions into the ground and underground water and the amount of green‐ house gas emissions is radically reduced. The project protects surface and underground water

The schematic presentation of the whole system is presented in Figure 1.

values between 15 and 20 MJ/kg.

**Parameter Value**

metals content: up to 2 %w

chlorine (Cl) content: up to 1 %w fluorine (F) content: up to 0,2 %w nitrogen (N) content: up to 1 %w sulphur (S) content: up to 0,3 %w

moisture content: between 20 and 45%

ash content: between 15 and 30%

calorific value: between 10 and 14 MJ/kg

**Table 4.** The certain parameters limits for RDF production and utilization

**3. Integrated waste management system**

quantities.

about 25 % of solids.

and prevents water pollution.

**Table 2.** RDF components characteristics

The average fraction composition of RDF, based on our investigations, is quite versatile but can still be presented with data in the Table 3. The data in the table is based on the research of Slovenian RDF produced from municipal solid waste.


**Table 3.** The average composition of Slovenian RDF

The MBT plant prepares the RDF according to the waste input stream quality, their technical capabilities and operation permits. Sometimes, to lower the operational costs, operators leave out certain sorting and processing systems thus produce coarser, lower-grade fuel with higher moisture and ash content. Still the RDF should be produced in accordance with the limits, set by the RDF utilizer. Such limits are for instance presented in Table 4 and were determined by the tests on pilot gasification unit by authors. If limits are not followed environmental and/or technical problems may arise during thermal treatment of RDF.

The primary task of MBT is mechanical waste preparation and aerobic microbiologic waste treatment with the aim to biologically stabilize waste and dry it. Mechanical separation of combustible and incombustible part of waste follows. The combustible part usually has heating values between 15 and 20 MJ/kg.


**Table 4.** The certain parameters limits for RDF production and utilization
