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SELECTING OPTIMAL REGIONAL MSW SYSTEM FOR THE KRAKOW AREA. Tomasz Stypka, Agnieszka Flaga-Maryańczyk stypka@gmail.com. The goal of the project:. to evaluate and compare the present and future municipal solid waste management systems in Krakow, Poland. Comparison of waste composition.
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SELECTING OPTIMAL REGIONAL MSW SYSTEM FOR THE KRAKOW AREA Tomasz Stypka, Agnieszka Flaga-Maryańczyk stypka@gmail.com
The goal of the project: • to evaluate and compare the present and future municipal solid waste management systems in Krakow, Poland.
Krakow: 2001 main assumptions: • Separate collection of recyclables, „bring” system located in 150 places around the city. • “Bring and earn” collection banks (paper, metal, glass). • Curb site collection of mixed household waste picked up from each household. • Composting of green waste (glass clippings and branches) and waste from farmers’ markets (fruit and vegetables)
Krakow: 2001 main assumptions: • Disposal at „Barycz” and other landfills in the Krakow neighbourhood.
Krakow – future state • Mass burn incinerator (200 000 tons/yr) • Two composting facilities (2 x 6000 tons/yr and 9000 tons/yr) • Sorting facility with the capacity of 20 000 tons/yr • Recycling system based on “bring” principle • The separate collection of dry and wet waste introduced in parts of town • Organic waste collected from green areas, farmers markets, community gardens, and individual home districts.
300 250 200 stage 2001 150 incineration 100 50 0 totalmass (kt) Total volume (000m3) Waste streams disposed at Krakow landfill according to two scenarios
Abiotic depletion for the two Krakow scenarios. • Hg responsible for 41% of the index at the thermal stage • SOx „savings” from LFG burning and energy production • Fluoresent lamps recycling promise large savings at the recycling stage
Climate change for the two Krakow MSWM systems • Methane requires special attention (21 GWP) • Low impact of the recycling, because the boarders of the system include the energy savings, but not the reduction of the emissions from the energy production
Human toxicity of the two Krakow MSWM systems • Incineration is 10 000 more toxic for humans than other stages • Collection equals landfilling • Cr (VI) is responsible for high index value. • Dioxins 500 more toxic than Cr, but • 0.1 g/yr dioxine • 1 277 kg Cr • If Cr(III) is emitted the emissions of nickel and arsenic become more important in the HTP index.(The emissions of dioxins still do not have significant impact on the HTP index value.)
Freshwater Aquatic Ecotoxicity of two Krakow MSWM systems • Air emission makes 99,9% of the total FAET • Hydrogen fluoride (HF) is the biggest contributor to the FAET and not because of its high toxicity, but because of the emission.volume; half of water environment toxicity is attributed to its presence in water. • Cumakes 21% of FAET • Ni makes 19% of FAET • Phenol at the collection stage has a negative impact (diesel production) • Leachate makes 99% of the FAET
Freshwater Aquatic Ecotoxicity of two Krakow MSWM systems • Leachate makes 99% of the FAET • 22 kg of AOX per year.(absorbable chlorinated organics; the equivalent amount of chlorine, bromine and iodine contained in organic compounds in water or wastewater, expressed as chloride) • AOX makes 89% of FEAT even the FEATP for AOX is comparable with Hg, Cd, Ni, and Cu. • Disposal of the ashes from the waste incineration does not have any significant impact on the water environment. • Recycling: Paper reduction by 44 090 Mg reduction of AOX110 kg. • Phenol is the second important pollutant responsible for the aquatic toxicity. 0,02% of the whole index.
Terrestrial ecotoxicity of the two Krakow MSWM systems • incineration 10 000 times bigger damage to the soil than the present system. • 101 kg (Hg)- 89%, 1280 kg of chromium (Cr)-7%, 507 kg of arsenic (As ) 2% and 507 kg of nickel (Ni) 1% • paper recycling reduces Hg emission by 0,0623 kg/yr (equivalent to 197 kg of 1,4 dichlorobenzene), which is twenty times higher than the emission from the present system.
Smog creation by two Krakow MSWM systems Diesel burning and plastic containers production result in emissions of hydrocarbons, nitrogen oxides, sulfur oxides, and carbon monoxide Methane at the landfill site
Acid rain creation by two Krakow MSWM systems No coefficient to reduce the impact of acidification Collection -Diesel burning, Energy savings included at the incineration stage 54% of the index value at the thermal treatment is caused by SO2 Recycling stage – energy savings are responsible for positive value.
Eutrophication caused by two Krakow MSWM systems NOx generated during the diesel oil combustion in trucks, Model estimates that at the present waste disposal scenario a collection stage generates 2,57*105 kg of NOx/yr; it is 97% of the total value of the eutrophication index.
Odour emissions from the two Krakow MSWM systems • IWM-1 Model estimates only 3 odour generating emissions • Waste incineration reduces approximately 100 times the odour nuisance. This is mainly caused by the reduced emission of hydrogen sulfide (H2S). • Reduction of H2S during the paper production gives positive value of odour index
The summary of the AHP procedure • Model the problem as a hierarchy containing the decision goal, the alternatives for reaching it, and the criteria for evaluating the alternatives. • Establish priorities among the elements of the hierarchy by making a series of judgments based on pairwise comparisons of the elements. • Synthesize these judgments to yield a set of overall priorities for the hierarchy. • Check the consistency of the judgments. • Come to a final decision based on the results of this process.
Establish priorities among the elements of the hierarchy by pairwise comparisons
Comparison of the impact of the two Krakow MSWSs on the natural environment
Sensitivity analysis: impact of the „natural environment” rating on the final result
Sensitivity analysis: impact of the „air” rating on the final result of analysis
Conclusions: • Present system is superior in: cost, abiotic depletion, human toxicity, freshwater aquatic ecotoxicity, terrestrial ecotoxicity, acidification, and eutrophication • New system is superior in: energy consumption, climate change, photochemical smog creation and odour creation and waste reduction. • Using the AHP method with the assumed relative weights shows that the new, proposed system of waste disposal in Krakow is a better solution than the present one
Conclusions: • The system with the incinerator and extensive recycling performs significantly better taking into account its impact on the natural environment, while the present system is cheaper and puts less stress on the manmade environment, • The new system performs well on the natural environment thanks to a good performance in the categories “impact on air” and “impact on soil”
Conclusions: • weights assigned at the top level of goals hierarchy, and weights assigned within subcategory „impact on the natural environment” are criticial in the whole analysis.
The end • Thank you for your patience and attention