HAZARDOUS WASTE MANAGEMENTCHE 252

Definition

HW include solid, sludge, liquids/ containerized gas or combination that may cause pollution damage to health and even death. This definition not include that which discharge directly into air/water.

UNEP (Dec 1985)HW means solid, sludge, liquids & containerized gas other than radioactive & infectious waste- by reasons of their chemical activities/ toxic explosive, corrosive or other characteristics cause danger to health/ environment whether along when coming into contact with waste.

ClassificationsThe basis to determine if the waste is hazardous occur two ways :-A) Lab testB) on the list of specific hazard waste

Lab testingCorrosivity (highly alkaline/ acidic)Ignitability (easily ignited & posing fire)Reactivity (potentially harmful, sudden reaction ie: explosion)Toxicity (capable release substance to water in significant conc)

20 top hazardous substances

Engineering classification system for hazardous waste

CategoryCharacteristicExamplesInorganic aqueous wasteLiquid waste composed primarily of water but containing acid/ alkali/concentrated solutions of organics hazardous substanceSpent sulfuric acid from galvanizing.Spent caustic bath from metal finishingRinse water from electroplating

Organic aqueous wasteLiquid waste composed primarily of water but containing admixtures or dilute concentration of organic hazard (pesticides)Rinse water from pesticides containers.Washing chemical reactors/formulation tanks

Organics liquidsLiquid waste containing mixtures/concentrated solutionSpent halogenated solvents from metal degreasing/dry cleaningDistillation residues from chemical intermediatesOils Petroleum derive oilUsed lubricating oil from internal combustion enginesUse hydraulic and turbine oils from heavy equipments

Engineering classification system for hazardous waste

CategoryCharacteristicExamplesInorganic sludge/solidSludge, dust, solid and other non-liquid waste containing inorganic hazardous substanceWaste treatment sludge from mercury cell process of chlorine productionEmission control dust from steel manufacture and smelters.Waste sand from coking operationOrganic sludge/solidTar, sludge, solid and other non liquid waste containing organic hazardous substanceSludge from painting operationsTar residue from production of dyestuff intermediatesSpent filter cake from production of pharmaceuticalsSoil contaminated with spilled solvents

Exposure routeEffects of HW

HW and their effects

SubstanceSNTMCeffectsLeadKidney, Brains damage to childrenArsenicRed+white blood cells decreaseMercuryKidneyCadmiumKidneyChromium

ORIGIN/SOURCE OF HWDeliberate add to soil, water/ air by humanEvaporation/wind erosion from waste dump into the atmosphereLeaching from waste dumps into ground water stream of water.Leakage from underground tank/pipelineEvaluation & subsequent deposition by accidents fire/explosionRelease from improper operated waste treatment storage.

Physical-chemical propertiesVapor pressure exerted by the vapor on liquid at equilibrium. Varies with T and measure in ATM.Solubility solute will dissolve into another solvent. Depends on T and chemical.Diffusion coefficient movement of a contaminant under influence of concentration gradient.Bioconcentration Factor (BCF)amount of a chemical that is likely to accumulate in aquatic organism.Sorption component moves from one phase to another boundary.

VOC (volatile organics compounds) easily to vaporise.Contaminant release can occur in liquids, solid or gas phase.

Liquids release- contaminated runoff, direct aqueous discharges to surface water, leachate to ground water.Air emissions- stack emission including gaseous and particulates and volatile emission from lagoons. Solid- suspended solid in water.Physical-chemical properties

TREATMENT & DISPOSALNeutralizationOxidationReductionReverse osmosisIon ExchangeCarbon adsorptionAcid removalPhenol destructionEvaporative strippingLand farmingIncinerationRecycle

Hazardous waste can be :TREATMENT & DISPOSAL