ABSTRACT
RESUMO Este trabalho apresentou estudos de custos de operação e manutenção (O&M) na estação de tratamento de esgotos (ETE) de nível terciário, intitulada ETE do Baldo, localizada na cidade de Natal, Rio Grande do Norte. Teve como objetivo avaliar a eficiência econômico-ambiental da ETE através da determinação de indicador de desempenho, calculado via identificação e quantificação de todos os custos operacionais e de manutenção envolvidos nos seus processos internos de tratamento. Na pesquisa, foram identificados os diversos componentes dos custos de O&M responsáveis pelas atividades necessárias ao funcionamento da ETE de julho de 2016 a dezembro de 2018, reunidos em quatro grupos de custos. Os custos mensais foram correlacionados com os dados de vazões do período, e os de O&M por metro cúbico de esgoto tratado ao longo dos anos de 2016, 2017 e 2018 assumiram valores médios de R$ 0,32, R$ 0,30 e R$ 0,38·m−3, respectivamente. Os custos referentes ao pessoal e ao consumo energético exerceram, em todos os meses analisados, o primeiro e o segundo componentes de maior representatividade no custo total, assumindo as seguintes composições percentuais: 56,72 e 26,75% no segundo semestre do ano de 2016; 46,69 e 28,73% no ano de 2017; e 52,44 e 27,56% no ano 2018. Por fim, recomendam-se estudos na implementação de melhorias nos grupos pessoal e energia, tendo em vista que são responsáveis por cerca de 75% de todos os custos de O&M da ETE.
ABSTRACT This study presented operational and maintenance costs (O&M) at the tertiary wastewater treatment plant (WWTP) entitled Baldo's ETE, located in the city of Natal, Rio Grande do Norte. Its aim was to evaluate the economic and environmental efficiency of the WWTP through the determination of a performance indicator, calculated from the identification and quantification of all the operational and maintenance costs involved in its internal processes of treatment. The research identified the various components of O&M costs responsible for the activities necessary for the operation of the WWTP from July 2016 to December 2018, assembled into 4 cost groups. The monthly costs were correlated with the flow data of the period. O&M costs per cubic meter of sewage treated over the years 2016, 2017, and 2018 assumed average values of R$ 0.32, R$ 0.30, and R$ 0.38·m−3, respectively. Personnel and energy consumption costs accounted for the first and second most representative components of the total cost in all the months analyzed, with the following percentage compositions: 56.72 and 26.75% in the second half of 2016; 46.69 and 28.73% in 2017; and 52.44 and 27.56% in the year 2018. Finally, studies on the implementation of improvements in the personal and energy groups are recommended, as they account for about 75% of all O&M costs of the WWTP.
ABSTRACT
El objetivo de esta investigación fue determinar el impacto económico de la variación del precio de leche en una finca lechera de Santa Bárbara de Barinas, estado Barinas, Venezuela. La metodología se basó en entrevistas, verificación de datos y revisión de informes. El período de estudio comprendió desde el 01 de enero al 31 de diciembre de 2011. El resultado económico consideró el valor y la estructura de costos de la producción y los indicadores de rentabilidad. Los resultados arrojaron que los costos de producción fueron distribuidos así: costos fijos (44%); costos variables (56%). Los insumos de mayor impacto económico fueron: alimento concentrado (47,29%) y mano de obra (26,60%). El costo de producción unitario de 1 litro de leche en bolívares (Bs./L) pasó de 2,62 a 2,43 Bs./L, desde el período enero-septiembre a octubre-diciembre 2011, respectivamente, variando el precio de venta unitario de 2,50 a 3,60 Bs./L en los períodos señalados. En consecuencia, hubo pérdidas económicas en el primer período, las cuales fueron compensadas con los ingresos procedentes de la venta de leche durante el segundo período, alcanzando ingresos netos (IN) de 80,98 miles de Bs./año. Con la venta de becerros y algunos animales de descarte, el IN total alcanzó los 88,69 miles de Bs./año. Se concluye, que bajo este esquema de regulación de precios del sector lechero, el sistema de producción de ganadería no es sostenible, pues sólo permite generar una relación beneficio/costo de 1,10; con una rentabilidad en la inversión del 3,03%. Se recomienda que el Estado venezolano establezca las medidas correctivas en el sector ganadero, para recuperarse de la crisis económica actual. Finalmente, el productor debe mantener un registro actualizado de costos, que podría ser utilizado como información de base, para la toma de decisiones sobre el negocio ganadero.
The purpose of this research was to determine the economic impact of the variations in the price of milk in a dairy farm, located in Santa Bárbara de Barinas, the State of Barinas, in Venezuela. The methodology used was interviews, data verification and reports review. The study period comprised from January 1 to December 31, 2011. The financial analysis considered both the value and structure of production costs, and the profitability indicators. The results showed that the production costs were distributed, as follows: fixed costs (44%) and variable costs (56%); the inputs with the greatest economic impact were concentrated food (47.29%) and labor cost (26.60%). The unit cost of production of 1 L of milk (Bs/L) decreased from 2.62 Bs./L to 2.43 Bs./L from the periods January-September to October-December 2011, respectively, with an increase in the unit selling price from 2.50 to 3.60 Bs./L in the periods indicated. Consequently, there were economic losses in the first period, which were set off with the incomes from the milk sales in the second period, reaching a net income (NI) of up to 80.98 thousand Bs./year. Adding the revenue from the sale of calves and some discarded animals, the total NI was 88.69 thousand Bs./year. It is concluded that, under the current scheme of price regulation in the dairy sector, the livestock production system is not sustainable, as it only generates a benefit/cost ratio of 1.10, with a return on investment of 3.03%. It is recommended that the Venezuelan Government establish corrective measures in the livestock sector to recover from the current economic crisis. Finally, the producer must keep an updated cost structure that can be used as a baseline information for the decision-making of the cattle business.
