WASTES INCINERATION PLANTS

Transcription

1 WASTES INCINERATION PLANTS

2 CRITERIA OF WASTE CLASSIFICATION FROM ENERGY UTILISATION STANDPOINT

3 MAJOR TYPES OF WASTES 1. Municipal 2. Medical 3. Industrial 4. Sewage sladge 5. Agriculture wastes 6. Building wastes 7. Opakowania 8. Ashes 9. Fuels from wastes

4 EU s WASTE CLASSIFICATION In EU (and in Poland) waste ore divided into 20 groups (which are followed by subgroups and sorts).

5 SAFETY CRITERION In every group and in every subgroup there are dangerous wastes, which were specified.

6 COMBUSTIBLE AND NONCOMBUSTIBLE WASTES Wastes could be divided from the standpoint of possibility of utilization of their heat of combustion: combustible, like: paper, plastic, wood, leather, gum, food, garden residues, fabrics and others, noncombustible, like: glass, ceramic, stones, metals and others.

7 CRITERION OF COMBUSTIBILITY OF WASTES Notion of combustibility: notion of combustibility is not obvious, it requires criteria of combustibility There are three major factors deciding on combustibility of wastes: o moisture content (< 50 %), o burning matter content (min. 25 %), o ash content (< 60 %).

8 TANNER S CRITERION OF COMBUSTIBILITY OF WASTES Tanner s diagram shows the area of combustibility of wastes.

9 WASTE INCINERATION PLANTS (WIP)

10 DEVELOPMENT OF WIP I st generation ( ) major objectives: reduction of volume of waste and maximum burning, development of furnaces waste burning (mainly grates), usually lack of heat utilization, lack of flue gas cleaning. II-nd generation ( ) dedusting of flue gas, utilization of waste heat (heat utilization boilers). III-rd generation ( ) reduction of gaseous pollutant emissions (mainly sulfur, chlorine and fluor compounds, reduction of heavy metals reduction, problems with safety of storage of solid residues, improvement of waste heat utilization. IV-th generation (1990-) improvement of effectiveness of flue gas cleaning, mainly from NOx, dioxins and furans, improvement of parameters of solid aside products of waste utilization (ash) to safety storage: - cement blocks, - vitrification.

11 CHARACTERISTIC FEATURES OF WIP 1. Reduction of wastes volume (up to 90%) and weight (up to 65%). 2. Wastes organic matter incineration. 3. Utilization of combustion heat of waste. 4. Meeting of gaseous pollutant emissions limits. 5. Safety of landfill of solid residue of waste incineration.

12 MAJOR COMPONENTS OF WIP a) Waste receipt and handling installation b) A combustion system c) Heat recovery system (boiler) d) Air pollution control system e) Combustion solid residue handling system

13 CONFIGURATION OF WIP Przetwarzanie wsadu Obróbka termiczna (spalanie) Odzysk ciepła Oczyszczanie spalin Odpady Składowisko Gorąca woda Para wodna Energia elektryczna Surowce wtórne

14 WASTES CINCINERATION SYSTEMS I. Incineration management waste burning, waste co-firing in: heating plants, power plants and cement plants II. Incineration technology waste combustion, waste pyrolysis, waste gasification. III. Waste type municipal solid waste incineration plants (MSWIP), sewage sludge incineration plants, hazardous waste incineration plants.

15 SOLID WASTES BURNING SYSTEMS

16 SOLID WASTES BURNING FURNACES 1. Pusher furnaces 2. Suspension burning systems 3. Grates 4. Fluidised bed systems 5. Rotary kilns 6. Multiple hearth furnaces

17 APPLICATIONS OF WASTE BURNING SYSTEMS Furnace Type of waste Jet furnaces Pusher furnaces Rotary kilns Fluidized beds Solid: grains, uniform, non-uniform, thick, organic compounds - with easy melting ash. Gaseous: heavy organic vapours. Liquid: organic liquids, water wastes with high content of organic compounds. Solids/sludge: sludge.

18 PUSHER FURNACES ADVANTAGES -simple design -low cost -easy maintenance -combustion control DISADVANTAGES -manual service -low capacity Pusher

19 ADVANTAGES -reliability -wide range thermal load variation -ability to burn different types of waste -low requirement of waste dispersion DISADVANTAGES -complicated drive -careful conservation required -expensive GRATES

20 MECHANISM OF WASTE BURNING ON GRATE

21 FLUIDIZED BED FURNACES ADVANTAGES: -long residence time -good burntout -ability to burn wastes with 60% of water -lack of mooving parts DISADVANTAGES -exploitation problems -complicated system of supply -large emissions of dust -require automatic control

22 Circulating fuidized bed boiler 91.2 MW th, 31.8 kg/s, 59 bar, 480 C FUEL: Industrial waste, Demolition wood PENDENT SUPERHEATER IDLE PASS CONVENTIONAL FURNACE AND SEPARATOR INTREX SH STOCKHOLM ENERGI AB HÖGDALEN, SWEDEN STEP GRID PIIRTEK OY Example of a waste sample

23 ROTARY KILNS

24 ROTARY KILNS ADVANTAGES: -good burntout -universal -wide range of the temperature -long residence time ( h) -ability to burn wastes of 60% of water -ability to burn waster of different shapes and sizes DISADVANTAGES -complicated design -limited capacity (< 8 t/h) -expensive

25 MULTIPLE HEARTH FURNACES ADVANTAGES: -ability to burn sludge -long residence time -good burntout DISADAVANTAGES -complicated design -require drive -limited capacity -expensive

26 RECOMMENDATIONS FOR APPLICATION Type of furnace OF SELECTED FURNACES municipal hospital/ medical Type of waste dangerous sewage sludge Grates n Rotary kilns Fluidized n Pyrolitic pushers ** - basic *- applied n not recommended

27 PROBLEMS OF BURNING OF SOLID WASTES

28 SELECTED PROBLEMS OF SOLID WASTES BURNING Dust emission Gaseous pollutant emissions Emission of dioxins and furans Landfill of waste ashes Exploitation of waste incinerators

29 PROBLEMS OF EXPLOITATION OF SOLID WASTE INCINERATORS Localization of waste incinerator Transport of wastes Odours from incinerators Landfill of waste ashes Safety of incineration staff Technical problems

30 SOME TECHNICAL PROBLEMS OF SOLID WASTED INCINERATORS Corrosion of heat-exchanging surfaces Burn throughout of grates Deposits at the hest exchanging surfaces Ash sintering and defluidization

31 ASH SINTERING Ash sintering in fluidized bed during sewage sludge burning Mineur M., The behaviour of a stationary fluidised bed upon the combustion of sewage sludge, VGB PowerTech, 12, 2002, pp

32 ASH DEPOSITION ON HEAT EXCHANGING SURFACES

33 CORROSION OF HEAT EXCHANGING SURFACES