What are the facts about incineration?

200,000 tonne incinerators
These incinerators are built with two operational lines (one is closed down for servicing whilst the other continues to operate). An additional third line is an option which may be added later (this is an option that East Sussex may pursue). A plant of this size employs 25 people, operational and administrative.

The process
Typically, Household Refuse and Trade vehicles arrive at the plant where they are weighed and logged. They then pass through automatically operated doors into a reception chamber. The waste is transferred to a refuse bunker where remotely operated overhead travelling cranes fitted with grabs lift the waste into feed chutes where it continues into the combustion chamber. The action grate in the chamber feeds burning refuse beneath the newly charged material causing it to be dried and ignited before passing down to the burning phase. Temperatures of between 800º and 1200º are required and the flow rate is controlled to ensure that all material is burned before it passes into the discharge chute. The ash is cooled and ejected onto a conveyor that serves both or all three lines. The conveyor takes the ash beneath a magnetic extractor and the ferrous metals are transferred to a storage bunker and the ash drops into an ash pit. The bottom ash is loaded into trucks using a hydraulic clam shell grab. The lorries then take the bottom ash for disposal. The hot gases are directed through to the reactor tower and are treated with hydrated lime and activated carbon before passing through a fabric filter. The flue gas and lime mixture is frequently re-circulated to optimise the process and approximately 20% of the cleaned gases are returned to the combustion chamber to reduce NOX emissions. The gases discharge into the atmosphere up through the chimney. The fly ash is contained in builders’ type material drawstring bags and trucked to specialist landfill for hazardous waste. That's the theory...

Input
Each line has an input of 11.41 tonnes of rubbish per hour, totalling 22.83 tonnes per hour. 547.92 tonnes of waste burnt per day which arrives by lorry. 250 lorry journeys during daylight hours = for example; one lorry every 2 minutes on the A27 and A26

Visible products
Fly ash and bottom ash accounts for 1/3 of the waste. The gases, water vapour and ultra fine particles such as mercury and cadmium emitted to air account for 2/3 of the waste. 4,800 tonnes of fly ash per annum 61,866 tonnes of bottom ash per annum (contaminated with heavy metals: lead, cadmium, arsenic, chromium and others) 66,666 equates to 13.15 tonnes of fly ash per day 169.49 tonnes of bottom ash per day Total 182.64 tonnes of ash per day to be loaded and transported away by road

Unseen products
A 200,000 tonne incinerator produces the equivalent of 385 million miles’ worth of vehicle pollution every year. 91,250 waste truck movements per year in the Ouse Valley alone amounts to 730,000 miles diesel pollution, plus 385,000,000 miles’ worth from the incinerator 385,000,000 this is 1,056,794 vehicles miles of pollution every day Emissions to Air Cadmium (Cd), Carbon Dioxide (CO2), Carbon Monoxide (CO), Lead (Pb), Mercury (Hg), Oxides of Nitrogen (NOx), Sulphur Dioxide (SO2) and Thallium (Tl) Particulates and adsorbed heavy metals Acid Gases – hydrogen chloride (HCl) and hydrogen fluoride (HF) Volatile organic compounds (VOCs) Dioxins and furans Arsenic (As), Antimony (Sb), Chromium (Cr), Copper (Cu), Manganese (Mn), Nickel (Ni) and Vanadium (V)[8]

Effects
Almost 100% of the elemental mercury present in the waste is emitted to air. The bottom ash contains heavy metals: lead, cadmium, arsenic chromium and others. Some of the ash escapes during transfer to lorries and subsequent transportation and disposal.

Environmental implications
The emissions from the chimney affect a radius of between ten and fifteen miles. The escaping dust and ash affect the immediate vicinity of the plant and also affect all along the ash trucks’ routes.

Health implications
There are four main areas of concern:- Acidic gases - hydrogen chloride, hydrogen fluoride, nitrogen oxides and sulphur dioxide, are responsible for respiratory irritations and pose further problems for asthma sufferers. Dioxins suppress the immune system, cause cancer, result in fewer male offspring, cause endocrine disruption, learning disabilities and behavioural problems. Dioxins pass through to babies in pregnancy and breast-feeding. Fine dust penetrates deep into the lungs and exacerbates asthma and other respiratory diseases. Heavy metals - Cadmium can affect the lungs and kidneys Lead causes nerve and brain damage, Mercury affects the central nervous system Further areas of concern Arsenic (As), Antimony (Sb), Beryllium(Be), Manganese(Mn), Nickel (Ni) Thallium (Tl) and Vanadium (V).

[Info supplied by Dove]

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