Displaying items by tag: Ash

Japan: Taiheiyo Cement has installed an ash washing facility at a waste incineration plant in Kumagaya, Saitama prefecture for desalination and lowering of chloride content. After rinsing, the installation will supplement cement production at Taiheiyo Cement’s 1.8Mt/yr integrated Kumagaya plant with up to 69,400t/yr of ash. The total cost of investment was US$7.17m.

Brazil: A research team at the University of São Paolo (USP) has concluded a study of cement hydration and pozzolanic activity when using 10% sugarcane bagasse (SB) and bamboo leaf ash (BLA) mixture. A paper released by the team has stated that the additive lowered the calcium hydroxide and heat required for hydration, saving on costs and emissions in cement production. Both binary and ternary concretes had higher compressive strengths with than without the mineral-rich additive. The study was supported by public and private funding.

US: Elixsys has completed a 100hr continuous pilot test to extract ammonium sulphate and calcium carbonate from flue gas desulphurisation solids at a coal-fired power plant in Pennsylvania. Products made using the company’s proprietary process meet the specifications for fertiliser-quality ammonium sulphate and technical-grade calcium carbonate.

The company intends to start a commercial-scale project of its technology in 2019 once it finds a utility partner. Full-scale operations are planned by 2022. The company is also starting pilot testing on another process to extract metals from coal ash.

Poland: Lafarge Poland officially opened the Siekierki ash separation plant in July 2018. The unit was developed with local power generation company PGNiG Termika. The plant uses technology from the US’ Separation Technologies, using its proprietry electrostatic process.

The unit converts fly ash into two products: ProAsh containing less than 5% flammable parts and HiCarbon fuel containing about 30 - 50% flammable parts. ProAsh ash is used as a construction product used in cement production, ready-mix concrete and prefabricated construction. HiCarbon is used as a fuel because it contains significant amounts of unburnt carbon and so it can be reused in furnaces.

The National Fund for Environmental Protection and Water Management (NFEP&WM) awarded the project a loan of around Euro9m. PGNiG Termika operates a 2078MW coal-power plant at Siekierki.

Italy: Cemitaly has been allowed to use slag and ash in cement production at its Taranto plant following an investigation, according to the Il Fatto Quotidiano newspaper. The former Cementir unit was investigated in 2017 as part of an illegal waste probe that examined whether the Taranto plant purchased ‘illegal’ by-products from Enel and the ILVA steel plant to produce cement.

UK: The UK Quality Ash Association (UKQAA) has appointed Tarmac’s Allan Everett as the association’s new chair, taking over from Power Minerals’ Ivan Skidmore. Everett will be joined by Richard Boult, who has also been announced as the UKQAA’s new Technical Committee Chair. Boult is Commercial Technical Manager at Cemex UK. He will work with UKQAA’s Technical Committee members to develop and assess technical projects exploring new sources and uses for quality ash.

The UKQAA is an industry association for the use of quality ash in construction and engineering applications and represents a range of members from across the construction supply chain.

Chile: AES Gener is exploring options to sell by-products from its Guacolda coal-fired power station to cement producers. The power-generation company has asked for permission to do so and has approached Polpaico, owned by Holcim, and BSA, owned by Hurtado Vicuna group, according to the Diario Financiero newspaper. Guacolda produces around 40,000t/yr of synthetic gypsum and 60,000t/yr of Ash. AES Gener is already selling 30,000t/yr or half of the ash generated at its Ventanas power plant, to Melón. The company also has agreements in place with a number of universities to explore the use of these materials in concrete, cement, agriculture and mining activities.

US: Georgia Power has started preparation activity to permanently close all of the company's 29 ash ponds located at 11 coal-fired generation facilities across Georgia. Twelve ponds are scheduled for closure by mid-2018, 16 are expected to close by 2026 and one pond is expected to close by 2030. At present, around 50% of the coal combustion by-products Georgia Power produces are used to make Portland cement, concrete, cinder blocks and gypsum wallboard.

"Our primary focus throughout the closure process is maintaining a reliable generation fleet, while conducting the closure process in the most efficient way possible," said Mark Berry, vice president of environmental affairs for Georgia Power. The company will upgrade each plant to accommodate the dry handling of Coal Combustion Residuals (CCR) required by new federal regulations. The closure of all 29 ash ponds is expected to cost over US$1bn over the next 10 years. In addition, the company has invested approximately US$5bn in new environmental compliance technologies for its coal-fired generation fleet.

US: According to Charlotte Business Journal, Duke Energy has proposed excavating 12 more of its 36 coal ash ponds in North and South Carolina and burying the waste in a fully-lined landfills or structural fill projects.

To date, Duke has proposed closure plans for 24 of the 36 ash ponds. In every case, it has proposed excavation and reburial. However, Garry Miller, head of closure engineering for Duke, said that might not be the case for the remaining 12 ponds. He said that the engineering work that remains to be done at those plants could yet show that a 'cap in place' process, which critics have said would be insufficient to protect against further contamination of groundwater, can effectively close them.

Miller said that none of the waste ash from Duke's 36 ash ponds would undergo beneficial reuse, the process of using the ash for commercial products such as a replacement for Portland cement in concrete and gypsum board. However, he added that Duke does send a portion of the dry ash it is currently producing at its largest plants for reuse. However, the time constraints imposed by North Carolina's Coal Ash Management Act of 2014 make it impossible for the existing ash ponds. "As we close these basins, the quantity in them is such that the market cannot handle it in a timely manner," said Miller.

Duke's current cost estimate for closing the ponds is US$3.4bn, although this is subject to revision.

Canada: A British Colombia programme that recycles Keurig coffee K-Cups into cement has been so successful that it may expand into Alberta. The Lafarge cement plant in Kamloops, British Colombia, Canada used about 1.4m K-Cups as ash in its cement in 2014 after teaming up with Van Houtte Coffee Services, which collects the used pods for recycling.

"I think we've been fairly successful here," said Eric Isenor, the Lafarge Kamlooops plant manager. "Van Houtte is happy with the programme so far and is looking to expand." He added that the company might start collecting the used pods in Alberta, Canada for recycling in British Colombia.

The single-serving coffee pods are not recyclable because they are a mixture of materials coffee grounds, a paper filter, plastic cup and foil top that cannot be efficiently separated. After collecting the used coffee pods, Van Houtte, a coffee service that delivers supplies to offices and retailers around Kamloops, brings them in large bins to the Lafarge cement plant for processing. The pods are dried out, shredded and heated to 2000°C to form ash, which is then used for cement production.