Patricia Torres

Plant biosolids composting of wastewater treatment

It was evaluated the bio solid composting in Canaveralejo Wastewater Treatment Plant in Cali - Colombia. Although the process was viable, the bulking agent (BA) incorporation improved the final product C/N relation. Municipal yard trimmings and sugar cane waste were the best bulking agent and amendment material, respectively. The B:BA:AM optimal relation, on percent, was 72:10:18. In terms of waste management and considering the increasing on the municipal wastewater treatment plants number, this study showed that the bio solid compost could be considered as a material with agricultural potential use; additionally when the option is just the bio solid final disposition, the composting process can reduce its disposal volume at 70%.

TRATAMIENTO DE AGUAS RESIDUALES DEL PROCESO DE EXTRACCIÓN DE ALMIDÓN DE YUCA EN FILTRO ANAEROBIO: INFLUENCIA DEL MEDIO DE SOPORTE

The cassava starch extraction produces wastewater with a high contamination level (COD: chemical oxygen demand) and acid character. The application of the anaerobic filter technology with three different supports medium showed that the best medium in terms of removal efficiencies COD and TSS (70 and 90% respectively) was the coconut shells. Additionally, this alternative is more competitive on prices and easy access as compared with another supports mediums.

Productive use of sludge from a drinking water treatment plant for manufacturing ceramic bricks

One of the most important problems for water treatment systems based on chemical coagulation process is the sludge generation, whose final disposition is made predominantly onto water, affecting their quality and potential uses. The productive use of this sludges represents a way to relieve some of the problems of solid waste management that helps in the recovery of natural resources and reduces the environmental pollution. This study allowed the evaluation of the use of aluminous sludge for the manufacture of ceramic bricks. The results show that it is feasible to use these sludges in partial replacement of one of the constituent materials of brick, in this case the sand in percentages above 10%; however, to avoid compromising the compression resistance it should be optimized the previous sludge dewatering to increase the potential waste-to-energy scheme. The brick obtained has appropriate characteristics for non-structural use.

Wastewater use in agriculture: irrigation of sugar cane with effluents from the Cañaveralejo wastewater treatment plant in Cali, Colombia.

In Valle del Cauca, south‐west Colombia, surface and ground waters are used for sugar cane irrigation at a rate of 100 m3 of water per tonne of sugar produced. In addition large quantities of artificial fertilizers and pesticides are used to grow the crop. Preliminary experiments were undertaken to determine the feasibility of using effluents from the Cañaveralejo primary wastewater treatment plant in Cali. Sugar cane variety CC 8592 was planted in 18 box plots, each 0.5 m2. Six were irrigated with conventional primary effluent, six with chemically enhanced primary effluent and six with groundwater. For each set of six box plots, three contained local soil and three a 50:50 mixture of sand and rice husks. The three irrigation waters were monitored for 12 months, and immediately after harvest the sugar content of the sugar cane juice determined. All physico‐chemical quality parameters for the three irrigation waters were lower than the FAO guideline values for irrigation water quality; on the basis of their sodium absorption ratios and electrical conductivity values, both wastewater effluents were in the USDA low‐to‐medium risk category C2S1. There was no difference in the sugar content of the cane juice irrigated with the three waters. However, the microbiological quality (E. coli and helminth numbers) of the two effluents did not meet the WHO guidelines and therefore additional human exposure control measures are required in order to minimize any resulting adverse health risks to those working in the wastewater‐irrigated fields.

Combined treatment of leachate from sanitary landfill and municipal wastewater by UASB reactors.

Landfills are among the most affordable and acceptable methods in terms of public health and environmental protection for the final disposal of solid waste. Leachate treatment incorporated into anaerobic domestic wastewater systems could be a viable and efficient alternative which would allow minimizing implementation and operation costs of the landfill, to reduce requirements of chemical inputs such as pH conditioners and phosphorus supply. This study showed the potential of anaerobic treatment in an UASB reactor treating a combination of domestic wastewater and leachate in a 5% volumetric ratio of leachate. Under these conditions the reactor assimilated properly the leachate fraction incorporated. With a HRT of 8 h and a mean volumetric organic load of 2.84 kg m(-3) d(-1) COD removal efficiencies around 70% were obtained, without inhibition problems; however, the necessity of a complementary treatment for improving carbonaceous and nitrogenous organic matter reduction is evident.

Perspectives for Sustainable Resource Recovery from Municipal Solid Waste in Developing Countries: Applications and Alternatives

© 2012 Marmolejo et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Perspectives for Sustainable Resource Recovery from Municipal Solid Waste in Developing Countries: Applications and Alternatives