Navegando por Assunto "Sludge"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Estudo da reciclagem de lodo de eta na fabricação de agregado sintético em mistura com cinza volante de carvão mineral
(Universidade Federal do Pará, 2016-11-22) SILVA, Elzelis Muller da; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968
The Wastes (sludge) generated in the Water Treatment Plants (WTP) and fly ash from coal-fired power plants cause problems by the amount and concentration of harmful substances in them. Thus, this study aimed to produce synthetic aggregates using sludge WTP Bolonha (Belém/PA) and fly ash assessing their technical and environmental viability. The composition of the synthetic aggregates consisted of a high concentration of these residues in mixture with clay to molding and sintering at temperatures of 1200°C and 1250°C. The physical, mineralogical and microstructural analyzes of the synthetic aggregate were performed. Two concrete were produced, one with synthetic aggregate, and other references. In concrete were assessed their physical and mechanical properties in fresh and hardened state, and their microstructures. For the characterization of the concrete waste leaching and dissolution testing were performed. Synthetic aggregates were classified as lightweight aggregate for its low bulk density (<2.0 g / cm3) according to NBR 7211 (ABNT, 2009). The concrete produced with sintered aggregate (AGS-02) at 1250 °C was classified as non structural lightweight concrete according to the norms NBR 6118 (ABNT, 2014) and NBR 8953 (ABNT, 2015). The concrete of waste were classified as waste class IIB, non-hazardous and inert by NBR 10004 (ABNT, 2004) and within the limits of Resolutions No. 20/1986 and 430/2011 CONAMA into rivers class 2. It is noteworthy the synthetic aggregate meets the demands of the construction industry, reduces the consumption of raw materials and offers an alternative to the final disposal of waste.
Acesso aberto (Open Access)
Estudo de viabilidade econômica da implantação de leito de secagem para tratamento de efluentes sanitários gerados em uma mineradora no estado do Pará
(Universidade Federal do Pará, 2022-12-28) FERREIRA, Cleyton Eduardo Costa; MENDONÇA, Neyson Martins; http://lattes.cnpq.br/7534816053779593
Waste management is one of the main challenges of modern society, especially when it comes to finding more sustainable and economical alternatives for the treatment and disposal of these materials. In this context, biosolids, a byproduct generated from wastewater treatment, have been identified as a possible source of nutrients and organic matter for agriculture and other sectors, thus contributing to a more circular economy. Biosolids contain a large amount of nutrients that can be used to improve soil quality and increase agricultural productivity (OLIVEIRA et al., 2018). In addition, the use of biosolids as fertilizer can reduce the need for chemical inputs, contributing to the reduction of the environmental impact associated with final disposal (RIBEIRO et al., 2015). This study was conducted in a mining company in the state of Pará, Brazil, which has eight decentralized anaerobic wastewater treatment plants. The study aimed to define the treatment route for biosolids, as well as to evaluate the economic viability of implementing a drying bed for the production of biosolids to be applied in the restoration of degraded areas. It was found that 11,776 kg of total suspended solids (TSS) per year of sludge are generated, resulting in the design of a drying bed with three cells, each with 22 m², an operation cycle of 25 days, and a Surface Application Rate of 13.30 Kg TSS/m²xdia. For sanitization, CaO was chosen. The implementation cost of the drying bed was R$ 100,358.70, operational costs were R$ 2,059.62/month, and the solution via incineration was R$ 18,415.80/month. Based on the simple and discounted payback, the investment returns in approximately 7.14 and 7.19 months, respectively, and is part of the synergistic costs with the current sanitation management. The other indicators point to the investment as viable and capable of financial surplus. Therefore, the company will have financial and environmental gains with the implementation of the project.
Acesso aberto (Open Access)
Importância da frequência de descarte de lodo na eficiência dos decantadores de estações de tratamento de água em ciclo completo
(Universidade Federal do Pará, 2004-10-20) CUNHA, Márcia Valéria Porto de Oliveira; PEREIRA, José Almir Rodrigues; http://lattes.cnpq.br/9918600634569244
In this work, different periods of discharge of the sludge stored in the decanters of the ETA Bolonha had been evaluated, with the purpose to recommend the operational routine that presents the best ones results in the efficiency of the decanters. The three experimental phases had been divided in three stages: being in phase 1 evaluated the efficiency of the current operation routine of the decanters what is the total discharge of sludge in 12 in 12 days. In phase 2, the operational routine was modified to a daily discharge during the time of 5 minutes and so it coud take care of the recommendations of the executive project; by the other hand, in phase 3, the operational routine was modified again, discharge of sludge of 5 in 5 days during the time of 5 minutes, in order to getting better results of efficiency. In these three phases it was realized the control of total suspended solids, dimming and color in the effluent tributary and, as well as quantified and characterized the sludge generated in the decanters. With the research it was possible to observe that according to the point of view of efficiency of the decanters, the implemented operational routine in phase 3 (discherge of sludge to each 5 days) it was showed more adequate. By the way, it recommends that tests with other operational routines should be done in order to remove the sludge deposited in the decanters to diminish the losses of water of this operation. Moreover, it is important to study other ways to remove the deposited sludge in the intermediate tray of the decanter to prevent the accumulation of sludge on tray.