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            "text": "Waste combustion",
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                "embedded_text": "moving cast\nsteel bars.\nThrough the\nforward movement 6. Heat from the flue\nof these bars the gases heats the\nwaste tumbles water in the boiler\nslowly down the tubes turning the\nburning waste bed. water into super\nThe resulting burnt heated steam. This\nout product – 4. Primary heated 5. Secondary swirling air steam drives the\nIncinerator Bottom combustion air drawn from introduced above the grate turbine which in turn\nAsh – falls from the above the waste bunker is through cylindrical nozzles drives the generator,\nbase of the grate distributed into the waste bed ensures that the gases in the producing electricity.\ninto a quench bath. through holes in each cast waste are thoroughly mixed.\nsteel grate bar. This process This results in a fully optimised\ndries the waste and provides combustion process and\nthe correct amount of air to encourages low levels of\nallow good combustion of the toxicity in the gases leaving the\nwaste bed. In compliance with combustion chamber. NOx\nthe Waste Incineration levels are reduced by ammonia\nDirective, the combustion injection to the levels required\nprocess operates at <850ºC. in the Environmental Permit.\nWestern Riverside Waste Authority"
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                "embedded_text": "1. The Incinerator Bottom Ash 2. The Incinerator Bottom Ash is 3. Incinerator Bottom Ash is\nwhich drops from the grate into a moved by overhead ash cranes from discharged from the hoppers\nquench bath is then pushed by the ash bunker into elevated loading ash containers.\nhydraulic rams onto vibrating hoppers which are positioned over an\nThese containers are transported\nconveyors and from there falls internal roadway.\nthe jetty on dock tractors and\ninto the ash bunker.\ntrailers and placed on barges to\nAny oversized metal or other taken to the IBA processing\nobjects fall off the conveyor into at Tilbury.\nskips to be recycled.\nAround 170,000 tonnes of ash\nyear is sent for processing.\nWaste reuse, recycling and energy recovery in your area – our way forward"
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            "id": "p4.7",
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            "text": "7. Gases and smoke produced during combustion are drawn through the gas passes of the boiler by an induced draught fan.",
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            "text": "1. Waste is fed into one of the three feed hoppers by the overhead cranes. The waste then travels down the chutes and onto a horizontal feeder table.",
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            "text": "2. Hydraulically operated ram feeders push the waste onto the sloping grate.",
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            "text": "3. The sloping stoker grate consists of alternate rows of fixed and moving cast steel bars. Through the forward movement of these bars the waste tumbles slowly down the burning waste bed. The resulting burnt out product - Incinerator Bottom Ash - falls from the base of the grate into a quench bath.",
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            "text": "6. Heat from the flue gases heats the water in the boiler tubes turning the water into super heated steam. This steam drives the turbine which in turn drives the generator, producing electricity.",
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            "text": "4. Primary heated combustion air drawn from above the waste bunker is distributed into the waste bed through holes in each cast steel grate bar. This process dries the waste and provides the correct amount of air to allow good combustion of the waste bed. In compliance with the Waste Incineration Directive, the combustion process operates at <850°C.",
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            "text": "5. Secondary swirling air introduced above the grate through cylindrical nozzles ensures that the gases in the waste are thoroughly mixed. This results in a fully optimised combustion process and encourages low levels of toxicity in the gases leaving the combustion chamber. NOx levels are reduced by ammonia injection to the levels required in the Environmental Permit.",
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            "text": "Incinerator Bottom Ash (IBA)",
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            "text": "DID YOU KNOW?\nIncinerator Bottom Ash is a by-product of the combustion process and accounts for approximately 28% of the facility's waste throughput.",
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            "text": "1. The Incinerator Bottom Ash which drops from the grate into a quench bath is then pushed by hydraulic rams onto vibrating conveyors and from there falls into the ash bunker.",
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            "text": "Any oversized metal or other objects fall off the conveyor into skips to be recycled.",
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            "text": "2. The Incinerator Bottom Ash is moved by overhead ash cranes from the ash bunker into elevated loading hoppers which are positioned over an internal roadway.",
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            "text": "3. Incinerator Bottom Ash is discharged from the hoppers into ash containers.\nThese containers are transported to the jetty on dock tractors and trailers and placed on barges to be taken to the IBA processing facility at Tilbury.\nAround 170,000 tonnes of ash per year is sent for processing.",
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            "text": "Western Riverside Waste Authority",
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