Soil and Waste Treatment - Waste Treatment PDF

Jordi Garrigó Reixach Subject: Soil and waste treatment Section: Waste treatment FIRST SEMESTER THIRD YEAR ENVIROMENTAL SCIENCE DEGREE SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH...

Jordi Garrigó Reixach Subject: Soil and waste treatment Section: Waste treatment FIRST SEMESTER THIRD YEAR ENVIROMENTAL SCIENCE DEGREE SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT GENERAL TOPICS UNIT 1: Sources and types of waste. Problem of waste. 2.1. Introduction UNIT 2: 2.2. Waste management Waste minimization. 2.3. Waste treatment. Thermal conversion Treatment of waste. UNIT 3: 2.4. Waste landfill Recovery of waste. Plans and waste management. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.1. Introduction Unfortunately, even today, wastes are deposited without any treatment in many parts of the world. This has dangerous consequences for the environment … Groundwater pollution Air pollution Biodiversity loss … and should be avoided. Sanitary risk Evolution of landfills numbers in U.E.S. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.1. Introduction TREAT THE WASTE! Energy Loss (Radiation) Final phase of Fuel treatment Waste sub products (recycled and recovered) Mass Loss (unburned C in ash and other waste) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management 20 – 30 Gallon containers Solid waste generation Paper and plastic bags Bulk bins Other Storage (US gallon = 3.785 L) Home separation for recycling Point service Level of service Citizens deliver Collected by Frequency of collection to recycling Transport truck center Direct transport Reuse Piggyback collection Recycled Transfer station separate vehicle Recovered Shred/hale Shred/pulp Energy recovery/ Material recovery thermal reduction Residue Incineration Pyrolysis Reuse as fuel Residue Land disposal SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management Collection Pick-up Landfill Treatment / Valorization Separation technologies Break bag Incineration Size separation Size reduction Thermal conversion Gasification Density separation Magnetic separation Pyrolysis Compression Biological conversion Composting Bio methanation Conversion technologies Ex.: landfill liner system Acid hydrolysis / alkaline hydrolysis Chemical conversion Methanol conversion SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Collection Collection Based on decisions made by elected representatives. The generated wasted can be collected by: -city employers -private firms that contrat with city goverment (contract collection) -private firms that contrat with private residents (private collection) MAIN POINT TO COLLECTION: separation of waste in the source is required! Colours can be different depends on the waste management legislation! SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection Paper and cardboard Plastics and containers Glass Organic Remain fraction SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection Bulky Electrical & electronic Equip. (WEEE) Textile Batteries Specialised companies Medicines and Drugs Used oil End-of-life tire (sp.NFU) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection “Yellow Container” YES (SÍ) NO Metallic cans Organic matter Drink cans (soda, refresh, beer,…) Glass packaging Cans of preserves (vegetables, meat, fish, pet food, …) Paper and carboard Aerosols (deodorant, lacquer, kitchen cleaners, wood polishes,...) Toys Aluminum trays and plates Appliances Metallic can and caps Biberons Tetra Brik Rubber gloves Brik of milk, cream, smoothies, juices, wine, … Kitchen utensils Plastic food packaging Fruit boxes Bottles (water, soft drink, milk, juice, oil, liqueurs, sauces,...) Plastic buckets Dairy product packaging (yogurts, flan and other milk desserts, cheese, butter, margarine,...) Batteries Trays and boxes made of "white cork", expanded polystyrene or EPS Plastic egg cups, disposable plastic caps, SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection Glass container (hemispherical) green. YES (GLASS) NO (“CRYSTAL”) Glass bottles of any color Vehicle glasses Glass jars (conserves, semiconserved honey, …) Lamps Cosmetic jar and perfume bottle Mirrors Window glasses Fluorescent tubes These "crystals" must be deposited in the "Clean Points" or in "Collection and Recycling Centers" SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Collection Paper and cardboard in container blue YES NO Newspapers and magazines Information, advertising, … leaflets Bricks Small cardboard boxes (biscuits, detergent, shoes,...) Diapers Egg cartons Dirty papers Paper bags Wax papers Cardboard boxes (chopped)? Metalized paper Plasticized paper SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection Organic matter WASTE IS PROHIBITED YES NO OUTSIDE THE CONTAINER Fruit and vegetable scraps Animal excrement (In the waste container) Cooked foods, dairy products, meat Glass, metals and plastics (in the and fish scraps. Container for yellow container) organic matter Diapers and sanitary napkins (in Natural sawdust, dirty kitchen paper the waste container) and wood ashes. Tobacco filters and sawdust made of treated wood (in the Coffee and infusion grounds and waste container) filters Clay, ceramic (in the waste Leaves, flowers and plants, green or container) dried Aluminum paper (in the waste Remains of orchard, lawn, and container) Garden chopped pruning Medicines, medicine containers composter Rice, boiled pasta, leftover nuts, and x-rays (at the pharmacy or chopped bread, eggshells and shells recycling center) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Collection Collection methods - door to door collection -waste containers curbside pickup -backyard pickup Door-to-door waste collection was the most used in the past and is still used in areas with high population density or with reduced sidewalk space. It generates problems with schedules, noise, dirt,... The system of street collection in waste containers being imposed. To take into account… DENSITY! SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Collection Collection methods Allows the selective collection of waste - waste containers curbside pickup Attention! Less populated - door to door collection areas → by requiring residents to transport waste -backyard pickup to a specific point. To take into account… DENSITY! SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Collection WASTE COLLECTION SYSTEM DESIGN CALCULATION: Estimating Truck Capacity ratio of the density after compaction to that before compaction SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Collection WASTE COLLECTION SYSTEM DESIGN CALCULATION: Estimating Truck Capacity stop SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Separation in the plant https://www.youtube.com/ watch?v=c2Tr-U0nALM https://www.youtube.com /watch?v=20Ihfe6X_UM Organic matter SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.2. Waste management. Separation in the plant Eddy current (Corrientes de Foucault) Eddy current separation (ECS) is a physical technology of separating nonferrous metallic particles from other particles. In ECS, alternating eddy current was induced in nonferrous metallic particles when meeting variable magnetic field generated by the rotation of magnetic drum of eddy current separator. The alternating eddy current caused a new magnetic field in nonferrous metallic particles. The magnetic field of eddy current separator and the new magnetic field had the same magnetic field direction. Thus, repulsive force between the two magnetic fields was generated and changed the movement of nonferrous metallic particles and separated them from other particles. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.2. Waste management. Treatment fractions RAEE Resíduos de Aparatos Eléctricos y Electrónicos WEEE Waste Electrical and Electronic Equipments SOURCE: State Framework Waste Management Plan (PEMAR 2016-2022) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Thermal conversion Heavy metals THERMAL CONVERSION Lead Inorganic mercury Acid gases Pollutant generated Methyl mercury Sulfur dioxide in those process Cadmium Nitrogen oxides Chromium Arsenic Organics … Dioxin and furans PCBs (polychlorinated biphenyls) INCINERATION GASIFICATION PYROLYSIS According to the needs of O2 and temperature THERMICAL CONVERSION O2 PRODUCTS INCINERATION EXCEED HOT GASES (N2, CO2, H2O) O2 SOLIDS (ASH) 900-1200ºC HOT INFLAMABLE GASES (N2, CH4, GASIFICATION DEFICIT CO2). SYNGAS. HEATING VALUE 5500 COKE (C, INERT) LIQUID 750-850ºC kJ/m3 PYROLITIC OIL HOT INFLAMABLE GASES (N2, CO, H2, COKE (C, INERT) PYROLYSIS ABSENCE GASEOUS HIDROCARBONS). (ACETIC ACID, 300-750ºC ACETONE, HEATING VALUE 26000kJ/m3 METHANOL) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Thermal conversion THERMAL CONVERSION INCINERATION Prior to 1940, incineration was common in North America and western Europe. Many incinerators were eliminated because of foul odors and dirty smoke environmental conflict! Pros: – Reduce volume 90%, weight 75% – Heat from burning converted to electricity Cons: – Can create air pollution – Concentrates toxins in ash – More costly than landfills SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Thermal conversion THERMAL CONVERSION MSW is not a very good fuel! SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  N2 2.3. Waste treatment. Thermal conversion. Incineration CO2 H2O INCINERATION O2 Reductions: Dioxins 90% volume Furans 75% weight Gas Scrubbing 900-1200°C System? Weighing scale Unloading point ash SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Thermal conversion. Gasification Ash / Slag Smokestack GASIFICATION Air + O2 Air 5 SOLID WASTE Electricity GASIFIER GAS PURIFICATION SYNGAS COMBUSTION + heat 1 C+ 1/2O2 CO 3 4 Water H2S 2CO + O2 2CO2 C+ O2 CO2 2 CH4 + O2 2CO2 + H2O C+ CO2 2CO NH3 6 C+ H2O CO + H2 Suspended Particles C+ 2H2 CH4 CO2 sequestration 750-850°C SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Thermal conversion. Pyrolysis PYROLYSIS 300-750°C SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Thermal conversion. Pyrolysis Pyrolysis of Solid Waste Pyrolysis is a thermal degradation of a substance in the absence of oxygen, whereby these substances are decomposed by heat, without combustion reactions occurring. The basic characteristics of this process are the following: The only oxygen present is the content of the waste to be treated. The working temperatures are lower than those of gasification, ranging from 300°C to 750°C. As a result of the process, the following is obtained: Gas, whose basic components are CO, CO2, H2, CH4 and more volatile compounds from the cracking of organic molecules, together with those already existing in the waste. This gas is very similar to the synthesis gas obtained in gasification, but there is a greater presence of tars, waxes, etc. to the detriment of gases, due to the fact that pyrolysis works at lower temperatures than gasification. Liquid waste, basically composed of long-chain hydrocarbons such as tars, oils, phenols, waxes formed by condensing at used temperature. Solid waste, composed of all non-combustible materials, which have either not been transformed or come from a molecular condensation with a high content of carbon, heavy metals and other inert components of the waste. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion BIOLOGICAL CONVERSION COMPOSTING BIOMETHANIZATION Compost microorganisms SPECIAL REQUERIMENTS ! The requirements are different for composting and for bio methanization. Acidogenic Acetogenic Methanogenic bacteria bacteria archaea Temperature Moisture Organic load (charge) Balance between C and N Technology Aerobic or anaerobic environment SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion Temperature < 20 ºC Psychrophilic (psychros gr  cold) 20-40 ºC Mesophilic 40-60 ºC Thermophilic > 60 ºC Hyperthermophilic Optimum Total Solids concentration 40-65% for composting 4-30% for biomethanization SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion C/N Ratio C/N ratio low – Excess N is lost as ammonia C/N ratio high – Microbes lack sufficient N and composting is slow OPTIMUN RATE: Microbes assimilate C Need starting ratio (C/N) of 30/1 or 40/1 Optimum Oxygen Level (in aerobic processes like composting) Composting microbes require at least 5% Optimum is 10% or more Atmosphere is 21% Insufficient oxygen – Anaerobic decomposition, little heat produced, slow composting – Produces methane and other odorous compounds SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion AEROBIC VS ANAEROBIC AEROBIC → Aerobic New Organic Matter + O2 + Microorganisms CO2 + H2O + NO3- +SO42- + Microorganisms Glucose aerobic degradation 38 adenosine C6 H12 O6 + 6O2 → 6CO2 + 6 H2O + ENERGY triphosphate, ATP ANAEROBIC Organic Matter + Anarobic Microorganisms → CH4 + CO2+ New Microorganisms Glucose anaerobic degradation Biogas: 0,8 m3 Biogas/kg glucose Composition 1:1 → (CH4 :CO2 ) C6 H12 O6 → 3 CH4 + 3CO2 Heat power: 4250 kcal/m3 1 m3 biogas = 0.6 L diesel (gasoil) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Composting “Coping” natural decomposition and humification to transform organic material into compost HUMUS? Pieces of fruit Vegetable scraps CO2and other gases Coffee beans Eggshells heat Grass and plant clippings Dry leaves water Finely cut wood and bark chips Shredded newspaper It is important that composter is in Straw O2 Garden contact with the "natural" soil to composter Sawdust from untreated wood ensure drainage and the load of microorganisms. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Composting COMPOSTING 1. Mesophilic phase Bacteria: 4. Maturation phase Gram- Bacteria: Pseudomonas Gram- Gram + Actinomycetes Bacillus Fungus: Lactobacillus Ascomycota Actinomycetes Zygomycota Fungus: Oomycote Ascomycota Algae Penicillium Nematoda Aspergillus Zygomycota Mucor 3. Cooling phase 2. Mesophilic phase Bacteria: Bacteria: Actinomycetes Bacillus Fungus: Thermus Source: Joaquín Moreno Casco (2008) Ascomycota Hydrogenobacter Basidiomycota Actinomycetes: Protozoa SOIL AND WASTE TREATMENT Streptomyces JORDI GARRIGÓ REIXACH WASTE NematodaTREATMENT 2.3. Waste treatment. Biological conversion. Composting COMPOSTING TECHNOLOGIES Static piles: is the simplest and least cost approach to composting large volumes of organic waste materials. Windrow (rows) composting: the way of setting the piles Passively aerated windrows (PAWS) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Composting COMPOSTING TECHNOLOGIES Forced aeration, static piles Enclosed (in-vessel) composting Vermicomposting (worms) Composting at home!!! SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Composting Criteria for fertilizers made from residues Concentration limits of heavy metals in fertilizers (solid or liquid) made from residues (mg/kg dry matter) Heavy metal A B C Cd 0.7 2 3 Cu 70 300 400 Ni 25 90 100 Pb 45 150 200 Ni 200 500 1000 Hg 0.4 1.5 2.5 Cr 70 250 300 Cr+4 No detectable según el método oficial Cr+6 is irritating and can cause blindness in prolonged exposure (in drinking water its limit is 0.05 mg/L according to the WHO). Cr+3 is considered an essential element. Real Decreto 506/2013, de 28 de junio, sobre productos fertilizantes. Ministerio de la Presidencia. «BOE» núm. 164, de 10 de julio de 2013. Referencia: BOE-A-2013-7540 SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Biomethanization 1. Receipt + mixture 5. Final products Heat Livestock Urban Solid waste Waste 3. Biogas treatment Power Biofilter electric Selection of turbines garbage bag Electricity 4. Phase separation Receiving tank Solid phase Post-digestion Centrifuge Agricultural Grinder use pump Digestion Liquid phase Mixing vessel Pasteurization Process line Heat line 2. Bio digestion Biogas line SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization Optimal pH Complex Organic Compounds carbohydrates, proteins, fats Hydrolytic bacteria 4.8 – 5.0 Hydrolysis Simple Organic Compounds Sugars, amino acids, fatty acids Acidogenic bacteria Acidogenesis 5.5 – 6.0 Organic acids and alcohols Acetogenic bacteria Acetogenesis 5.5 – 6.0 Acetic acid H2, CO2 Acetate Methanogenic archaea CH4, CO2 Methanogenesis 6.5- 7.2 (biogas) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization High solids Typical mass balance (dry anaerobic digestion) 20-30% TS SSO (Source-Separated Organics) TS, Total Solids SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Biomethanization Low solids Typical mass balance (wet anaerobic digestion) 4-10% TS SSO (Source-Separated Organics) TS, Total Solids SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization Configurations AD (Anaerobic Digestion) 35ºC 55ºC SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.3. Waste treatment. Biological conversion. Biomethanization Configurations AD (Anaerobic Digestion) Mechanical Shaker Shaker Shaker OFUSW OFUSW BIOGAS INPUT BIOGAS INPUT BIOGAS Thermophilic Heating Reactor Heating Mesophilic Reactor Anaerobic Heating Reactor THERMOPHILIC OFUSW EFFLUENT Organic fraction of MESOPHYLIC EFFLUENT Urban Solid Waste EFFLUENT OUTPUT SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization Typical Biogas Parameters Biogas CH4: 60% by volume CO2: 40% by volume H2S: 200 to 4000 ppm Trace contaminants (highly variable): siloxanes, chlorinated organics and VOCs Biogas yield Methane Methane yield Waste Type (m3/Tm waste) (%) (m3/Tm waste) Leaves 23 60 24 Grass 34 60 20 Mixed paper 112 60 67 Brush 67 60 40 Food waste 144 60 86 FOG (Fats, Oil and Grease) 390 60 234 SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization Biogas upgrading Two steps involved in biogas treatment: Cleaning (removal of minor impurities components of biogas) Upgrading (removal of CO2 content) aims to increase the low calorific value of the biogas, and thus, to convert it to a higher fuel standard The final product is called biomethane which composed of CH4 (95– 99%) and CO2 (1–5%), with no trace of H2S. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization + Composting SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.3. Waste treatment. Biological conversion. Biomethanization + Composting BIOMETHANIZATION..common in developing countries Fuel Animal Dung Biogas plant Light Biofertilizer SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill Types of landfills Real Decreto 426/2020, de 7 de julio, por el que se regula la eliminación de residuos mediante depósito en vertedero. Legislación basada en la Ley 22/2011, de 28 de julio, de residuos y sueños contaminados. Residuos peligrosos: residuo que presenta una o varias de las –Hazardous waste landfills características… H1 Explosivo, H2 Oxidante…etc. Residuos no peligrosos: residuos que no están cubiertos por el –Non-Hazardous waste landfills apartado e) del artículo 3 de la Ley 22/2011 Residuos inertes: aquellos residuos no peligrosos que no experimentan – Inert waste landfills transformaciones físicas, químicas o biológicas significativas. “Liquid” waste Infectious waste Tires (NFU) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.4. Waste landfill Site selection for the disposal of solid wastes In choosing a localization for a landfill, consideration should be given to the following variables: -Public opposition A landfill should be located more than: -Proximation of major roadways -300 m from water streams --Speed limits -500 m from houses, schools and --Load limits on roadways parks -Bridge capacities -No minimal distance from airport -Traffic patterns and congestion runways (but more than 10.000m) -Haul distance (in time) -Hydrology -Availability of cover material -Climate (for example, floods, mud slides, snow…) -Zoning requirements -Buffer areas around the site (for example, high trees on the site perimeter) -Historic buildings, endangered species, wetlands and similar environmental factors) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.4. Waste landfill SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  Landfill barriers 2.4. Waste landfill Hazardous Non-Hazardous Inert waste waste landfills waste landfills landfills MASS OF WASTE MASS OF WASTE MASS OF WASTE DRAINAGE LAYER ≥ 0.5M DRAINAGE LAYER DRAINAGE LAYER ≥ 0.5M for leachate collection for leachate collection for leachate collection WATERPROOF ARTIF. LINING ARTIFICIAL GEOLOGICAL WATERPROOF ARTIF. LINING ARTIFICIAL GEOLOGICAL BARRIER ≥ 0.5m BARRIER ≥ 0.5m When the natural geological ARTIFICIAL GEOLOGICAL When the natural geological barrier is not enough BARRIER ≥ 0.5m barrier is not enough When the natural geological NATURAL GEOLOGICAL barrier is not enough NATURAL GEOLOGICAL BARRIER BARRIER Material of permeability and NATURAL GEOLOGICAL Material of permeability and thickness equivalent to: k ≤ 1.0 BARRIER thickness equivalent to: k ≤ 1.0 x 10-7 m/s and thickness ≥ 1m Material of permeability and x 10-9 m/s and thickness ≥ 1m thickness equivalent to: k ≤ 1.0 x 10-9 m/s and thickness ≥ 5m >5m >1m >1m SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill Environmental risks: Excessive slope → Stability Inadequate waterproofing of the base → Leaching non-controlled Mismanagement of the gases generated → Air pollution Slipping of the waste mass on the impermeable layer → Stability Air pollution Biodiversity impact Groundwater pollution Soil fertility effects Visual and health impacts SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill Operating methods employed in landfill The trench method: used on level or gently sloping land where the water table is low. A trench is excavated. The solid waste is placed in it and compacted. The soil that was taken from the trench is laid on the waste an compacted. The area method: the solid waste is deposited on the surface, compacted and covered with a layer of compacted soil. The cover material may come from on or off site SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill Sectional view through a MSW landfill TRENCHES Length: 30 – 300 m Widths: 5 – 15 m Depth: 3 – 9 m Source: Tchobanoglous et al., 1993 SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  Landfill barriers 2.4. Waste landfill The regularization, waterproofing and drainage layers will be placed if necessary, in the opinion of “the competent authority” for the authorization of the closure of the landfill. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill LANDFILL GASES natural byproduct of the decomposition of Typical constituents found in Municipal Solis Waste organic material in anaerobic (without landfill gas oxygen) conditions. It contains several % Component gases: (dry volume basis) Methane 45- 60 The generation of landfill gases depends on: Carbon dioxide 40- 60 Nitrogen 2- 5 Waste composition (in particular the amount Oxygen 0.1- 1.0 of readily degradable organic material). Sulfides, disulfides, mercaptans,… 0- 1.0 Age of waste. Ammonia 0.1- 1,0 Density of the waste. Hydrogen 0- 0.2 Moisture content and its distribution through Carbon monoxide 0- 0.2 the waste mass. Trace constituents 0.01- 0.06 Acidity / alkalinity (pH). Characteristic Value Nutrient availability. Temperature (°C) 35-50 Temperature. Density (g/cm3) 1.02- 1.05 Presence of toxic agents and chemical Moisture content Saturated inhibitors High heating MSW:value (kJ/m3Solid Municipal ) Waste 16,000- 20,000 Source: Tchobanoglous et al., 1993 SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT 2.4. Waste landfill Evolution of the landfill gases SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  Valorization of landfill gases 2.4. Waste landfill Collection of landfill gases How methane gas flow from the landfill and through filters to provide both heat and electricity Suction Scrubber (purifier) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill -Rainfall Leachate -Surface drainage Liquid that passes through the landfill and that has -Groundwater extracted, dissolved and suspended matter from it. come from -Liquid produced from the decomposition of the waste Leachate constituents Source: Tchobanoglous et al., 1993 SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  Landfill barriers 2.4. Waste landfill Non hazardous waste Non hazardous waste Inert waste high biodegradable low biodegradable Hazardous waste organic matter (>15%) organic matter (0.30m) MINERAL DRAINING LAYER MINERAL DRAINING LAYER REINFORCING WATERPROOF GEOSISNETTIC or CLAY (>0.30m) (>0.30m) BARRIER Waterproofing WATERPROOF BARRIER WATERPROOF BARRIER MINERAL WATERPROOF Non-compulsory REGULARIZATION LAYER BARRIER (K≤10-9 m/sec. in 1m GAS COLLECTION LAYER GAS COLLECTION LAYER GAS COLLECTION LAYER (if deemed necessary) (if deemed necessary) REGULARIZATION LAYER REGULARIZATION LAYER REGULARIZATION LAYER (≥ 0.50m) (≥ 0.50m) (≥ 1 m) WASTE MASS WASTE MASS WASTE MASS WASTE MASS Desarrollo técnico del Real Decreto 181/2001 relativo a las instalaciones dede vertido de residuos (in BOE-A-2002-1697-consolidado) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill The “bathtub effect” (sp. “efecto borde de bañera”) is the accumulation of infiltrated leacheate above the impermeable liner. SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  2.4. Waste landfill A secure landfill design for toxic or radioactive waste disposal SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT  Main ideas from UNIT 2 Separation at the source is the key-factor to a appropriate valorisation of wastes The collection of wastes can be different depending on the management Biological treatments are applied to organic substrates Environmental requirements are crucial for microorganism involve in biological treatments Thermal valorisation is one of the easiest way to treat the waste, but other more sustainable approaches should be studied Landfill has to be avoided as final destination of wastes Construction of landfills has to be done following the legislation and technical procedures to avoid environmental risks and, always, depending on the nature of waste. The landfill is a “living being” which evolves until maturation (leachates and biogas composition) SOIL AND WASTE TREATMENT JORDI GARRIGÓ REIXACH WASTE TREATMENT