Environmental Problems, Their Causes, and Sustainability 1

Power plantSteamElectricityTurbineGeneratorSmokestackCraneWetscrubberBoilerFurnaceElectrostaticprecipitatorConveyorWaste pitWaterBottomashDirtywaterFlyashConventionallandfillWastetreatmentHazardouswastelandfillFigure 24-12 Solutions: waste-to-energy incinerator with pollution controls that burns mixed solid waste andrecovers some of the energy to produce steam used for heating or producing electricity. (Adapted from EPA,Let’s Reduce and Recycle)problems because of the difficulty of having to constantlyadjust combustion conditions for differentmixes of trash.In refuse-derived fuel incinerators, burnable waste isseparated from unburnable and recyclable materials.Burning only combustible waste produces more energyand also leads to less air pollution.Figure 24-13 lists the advantages and disadvantagesof using incinerators to burn solid and hazardouswaste. Study this figure carefully.Since 1985, more than 280 new incinerator projectshave been delayed or canceled in the United States becauseof high costs, concern over air pollution, and intensecitizen opposition.Figure 24-13 Trade-offs: advantages and disadvantages of incineratingsolid waste. These trade-offs also apply to the incineration of hazardouswaste. Pick the single advantage and disadvantage that you thinkare the most important.AdvantagesReduced trashvolumeLess need forlandfillsLow waterpollutionQuick andeasyT rade-OffsIncinerationDisadvantagesHigh costAir pollution(especiallytoxic dioxins)Produces ahighly toxic ashEncourageswaste productionDiscouragesrecycling and wastereduction546 CHAPTER 24 Solid and Hazardous Waste