First major milestone reached as incinerator construction continues

In a little over 17 months, much of the waste produced in Meath will be incinerated and converted to electricity at Carranstown, Duleek. The controversial incinerator being built by Indaver Ireland is currently taking shape in the shadow of the Irish Cement plant at Platin, with the tipping gates, waste bunker and lift-tower aleady in place. Up to 300 workers will be working on site over the next year, installing the extensive technology which will run the facility. The company has appointed Bart Verlinden, a Belgian with extensive experience of running incinerators, to manage the facility in keeping with Indaver's EPA licence which stipulates that the site must be managed by someone with over 10 years' experience of running such a facility. The incinerator is expected to start accepting waste in May 2011 with test commissioning due to take place the previous February. Work on the facility began in September of last year in what was once a potato field in a prime agricultural area outside Duleek. There are currently 80 people working on-site and, as work continues in 2010, there will be 300 people working there. After a decade-long planning process and thousands of objections, the proposed waste-to-energy plant at Carranstown is finally taking shape. According to Jane Hennessy of Indaver, the planning period took so long that technology has made great strides in the interim and she says the new facility will be even cleaner and more efficient that when first mooted. Commitment "We are committed to minismising the impact of the facility on the local community and, for that reason, the incinerator itself will be located to the rear of the site. When the work started last year, it initially involved taking soil from the fields and building mounds of earth, or berms, to shield the whole thing from the road," she said. She added that the road outside the plant was widened and a turning lane was provided to reduce the impact of the site on traffic. The biggest milestone at the site so far was the excavation and construction of the bunker which will hold the waste for incineration and which will be capable of holding 10 days' supply of rubbish. The excavation of the waste holding area, or waste bunker, was completed in October. The watertight floor is over one metre thick and consists of layers of concrete and a specalised liner. The concrete floor slab of the waste bunker was poured on 11th November. Over 110 trucks delivered concrete over a 12-hour period from local concrete plants and the total volume poured was 918 cubed metres. The cement was supplied by Kilsaran Concrete and came from four local quarries. Progress continues on the site and the main structures visible at present include the waste bunker, six-storey lift shaft and stairwell and waste reception or tipping gates. The international Irish-owned PM Group is carrying out the engineering design and construction management of site and other key suppliers are Babcock and Wilcox Vølund, a Danish provider of the waste-fired power plant technology; LAB, a French supplier for the flue gas cleaning system, and MWH for process design integration. John Sisk and Sons are civil contractors on site. Offices on site - which were provided by Meath company, Insta Space - include a visitors room where the local community can meet with Indaver and see what is going on at the site. "Indaver works with the Irish-owned main contractors on-site to ensure that as many subcontractors as possible are locally-based firms," according to Jane Hennessy. Some of the local companies on-site include C&M Construction, Duleek; Cemex Ltd, supplying stone from Annagor quarry, Duleek; Cianans Cleaning Services, FSA Construction Ltd, and all reinforcement bars supplied to the site is from Fairyhouse Steel, based in Ratoath. Jade Scaffolding, Navan; Keegan's Quarries, Kilsaran Concrete Products and Panda Waste are also among those providing services on the site A local Mace shop is also based on-site, feeding workers and providing the essentials. Jane Hennessy said that, by next February, the bunker will be completed, gas cleaning components will be installed in March and, by February 2011, cold commissioning will take place to make sure that everything is working. The first burning of waste should begin the following May. Bunker When the incinerator is finally commissioned in 2011, waste will be accepted at tipping gates where it will be tipped into the bunker in an enclosed building. Giant fans will suck the waste through the system, ensuring no odours or litter. Grabs will pick up the waste, ensuring an even mix and feeding the material into a hopper and grate furnace, where it will be burned at 850 degrees. The control room will constantly monitor the stack for emissions. The heat generated by the furnace will heat up a boiler, creating steam to drive a turbine which will generate electricity which will be used on-site. An additional 15mW or more will be fed into the national grid - that is sufficient to heat 20,000 homes per year. Metals will be recovered from the bottom ash and boiler ash and will be collected in a silo and sent off-site for disposal. The incinerator will use a sophisticated gas cleaning system which will use recycled water from the process to cool gases and lime will be injected to remove acids and activated carbon will be injected into the flue gas to absorb dioxins, heavy metals and other hydrocarbons Activated carbon (with adsorbed particulates) is removed by the baghouse filter, which is the first stage dioxin removal. Before leaving the stack, the flue gas will pass through a monitoring station connected to the control room which will continuously monitor temperature and emmissions. As work continues on the Duleek site, project engineer Oliver Kelly uses sophisticated software which allows him to 'virtually walk through' the development, checking that everything fits in with the proposed design and is in line with the original plan. He said that, since the planning process first started, things have become more efficient. They will be using higher efficiency pumps and will reuse as much heat and energy as possible.