RESUMO

Sewage sludge contains plant nutrients and organic matter in its composition, making it a potential partial substitute for mineral fertilizers if it meets environmental, agronomic, and sanitary standards. The objective was to evaluate the content of nutrients and heavy metals in the sludge generated in four wastewater treatment stations (WWTPs) in Rio de Janeiro state and assess its potential value and usefulness. The samples of 19 batches from the WTTPs Alegria, Barra da Tijuca, Ilha do Governador, and Sarapuí were analyzed. The WWTPs differ in methods and processes used for treating sewage and sludge. The total contents of C, N, P, K, Ca, Mg, Fe, Al, Na, Co, Mn, As, Ba, Cd, Cr, Cu, Ni, Se, Pb, and Zn were evaluated, as well as the ratio C/N, pH, organic matter content, and electrical conductivity. The grouping of sludge samples was assessed using principal components (PCA) and cluster analysis. The economic valuation of sludge was conducted utilizing the substitute goods method, which compared the sludge's N-P-K contents with the prices of consolidated nutrient sources. All the evaluated sludge batches exhibited concentrations of heavy metals below the limits allowed by Brazilian law, along with high levels of nutrients and organic matter. Considering the chemical characteristics, all evaluated materials showed potential for agricultural use, but it is crucial to evaluate the microbiological characteristics of sludge batches before agriculture application. PCA and cluster analysis demonstrated that sludge samples from the same WWTP clustered close to each other, demonstrating higher similarity among themselves than with samples from other WWTPs. The sludge had an average added value of U$ 88.46 per megagram, considering the total contents of N, P, and K in its composition. Land application of sewage sludge can reduce the need to purchase mineral fertilizers, thereby supporting the feasibility of reusing this material in the agricultural sector.

Assuntos

RESUMO

The waste generated in the production of wine and grape juice is characterized by a high concentration of organic matter, when properly treated, can serve as sustainable strategies for its use and destination, and among these, the production of biocompost. Thus, the objective of this study was to evaluate the process of composting grape marc, sheep manure, and mango leaves, evaluating in the biocompost its physical-chemical, nutritional and microbiological characteristics for use in agriculture. The composting pile assembly followed the proportion of 30% of sheep manure as nitrogenous material and 70% of carbon-rich material (divided into 50% of grape marc and 20% of hose leaves), the initial C/N ratio was 33:1, and the process lasted 120 days according to legislation. When evaluating the results, the process occurred in an accelerated manner, where at 30 days the biocompost was already stabilized, and at the end of the process (120 days) it presented a C/N ratio of 5.85, as well as acceptable levels for the macronutrients K and P, and without risk of phytotoxicity, and could be used as organic fertilizer or as soil conditioner, reducing environmentally inadequate destination and generating savings with their reinsertion in the production chain.

Assuntos

RESUMO

The Brazilian Biodigester Septic Tank (BBST) is an on-site appropriate technology for blackwater treatment, which was developed to yield an effluent suitable for agricultural use. Although several studies have proven its efficacy for secondary blackwater treatment, there are few published studies about the microbiological quality of its effluent, and most of them focus on the quantification of total or thermotolerant coliforms. This study evaluates the performance of a BBST for the removal of human adenovirus (HAdV), Enterococcus spp., Salmonella sp., and Escherichia coli. The results further clarify the safety and risks associated with the reuse of the obtained effluent. The full-scale system consists of three 1.2 m3 interconnected reactors, with a blackwater input of 0.045 m3/day, and hydraulic retention time of 80 days. Six sample campaigns were performed at different stages of the monthly operating cycle. The system presented an average removal efficiency of 5.09 log10 for E. coli, 3.22 log10 for Enterococcus spp., 1.2 log10 for Salmonella sp., and 3.0 log10 for HAdV. According to the World Health Organization standards, the obtained effluent is suitable for subsurface irrigation, and for use in crops that develop distant from the soil or highly mechanized crop systems.

Assuntos

RESUMO

Large volumes of produced water are generated as a byproduct in activities of oil and gas exploitation, which can be reused in agriculture after a treatment process. Activated sludge treatment has been successfully used to remove oil from wastewater, but systematic studies on the toxicity of this effluent using this treatment are scarce in the literature. In this study, it was investigated the performance of an activated sludge system in the treatment of a synthetic produced water under different initial conditions in terms of salinity and oil and grease concentration. Furthermore, it was evaluated this effluent phytotoxicity in the germination, and seedling and plant growths of sunflower and corn seeds using untreated and treated synthetic produced water. Results revealed the activated sludge effectiveness in oil and grease and salinity removal from produced water, viz. high removal efficiency of 99.01 ± 0.28 and 91.07 ± 0.39%., respectively. Untreated produced water showed considerable toxic effects on the germination (74.67 ± 2.31% and 82.67 ± 2.31 for sunflower and corn seeds, respectively) and growth stages of sunflower and corn seed plants. The germination percentage was approximately 100% for both types of seed. The seedling and plant growth of the two seeds irrigated with treated produced water had similar performance when used tap water. These results highlighted the potential reuse as an unconventional water resource for plant irrigation of the synthetic produced water treated by an activated sludge process, which technology has showed high removal performance of salinity and oil.

Assuntos

RESUMO

The swine confinement farms and the improper disposal of their wastes carry result in contamination of water and soil. On many farms is common slurry application to soil as a means of fertilization, but without any control over the quality of the effluent being released. What is a parasite Ascaris suum from pigs can infect humans, but is not given due importance to the presence of this contaminant as soil and water. In this work the effluent of a pig was treated in a system composed of anaerobic baffled reactor (ABR) and a UASB followed by polishing ponds for removal of helminthes eggs. The experiment was conducted at the Hélio Barbosa Experimental Farm pig in the city of Igarapé / MG. Values found in the influent of helminthes eggs in the range from 2891 to 88,848 eggs L-1, while the effluent showed absence of eggs, showing the high efficiency of the treatment system. While the sludge ponds, it showed high concentration of viable eggs ranged from 10.1% to 59.8%, not being in conformity with the requirements for reuse in agriculture.(AU)

Os confinamentos suínos e a disposição inadequada desses dejetos trazem como consequência a contaminação de águas e do solo. Em muitas granjas é comum a aplicação dos dejetos ao solo como forma de fertilização, porém, sem nenhum controle sobre a qualidade do efluente que está sendo lançado. O Ascaris suum é um parasita de suínos que pode infectar humanos, porém não é dada a devida importância à presença deste como contaminante do solo e água. Neste trabalho o efluente de uma suinocultura foi tratado em um sistema composto por reator anaeróbio compartimentado (RAC) e um reator anaeróbio de manta de lodo UASB seguido de lagoas de polimento para remoção de ovos de helmintos. O experimento foi realizado na suinocultura da Fazenda Experimental hélio Barbosa em Igarapé/MG. No afluente foi encontrado valores de ovos de helmintos na faixa de 2.891 a 88.848 ovos L-1, enquanto o efluente apresentou ausência de ovos, mostrando a alta eficiência do sistema de tratamento. Quanto ao lodo das lagoas, este apresentou elevada concentração de ovos viáveis variando entre 10,1% a 59,8%, fora dos padrões preconizados para a sua utilização na agricultura.(AU)

Assuntos

RESUMO

The swine confinement farms and the improper disposal of their wastes carry result in contamination of water and soil. On many farms is common slurry application to soil as a means of fertilization, but without any control over the quality of the effluent being released. What is a parasite Ascaris suum from pigs can infect humans, but is not given due importance to the presence of this contaminant as soil and water. In this work the effluent of a pig was treated in a system composed of anaerobic baffled reactor (ABR) and a UASB followed by polishing ponds for removal of helminthes eggs. The experiment was conducted at the Hélio Barbosa Experimental Farm pig in the city of Igarapé / MG. Values found in the influent of helminthes eggs in the range from 2891 to 88,848 eggs L-1, while the effluent showed absence of eggs, showing the high efficiency of the treatment system. While the sludge ponds, it showed high concentration of viable eggs ranged from 10.1% to 59.8%, not being in conformity with the requirements for reuse in agriculture.

Os confinamentos suínos e a disposição inadequada desses dejetos trazem como consequência a contaminação de águas e do solo. Em muitas granjas é comum a aplicação dos dejetos ao solo como forma de fertilização, porém, sem nenhum controle sobre a qualidade do efluente que está sendo lançado. O Ascaris suum é um parasita de suínos que pode infectar humanos, porém não é dada a devida importância à presença deste como contaminante do solo e água. Neste trabalho o efluente de uma suinocultura foi tratado em um sistema composto por reator anaeróbio compartimentado (RAC) e um reator anaeróbio de manta de lodo UASB seguido de lagoas de polimento para remoção de ovos de helmintos. O experimento foi realizado na suinocultura da Fazenda Experimental hélio Barbosa em Igarapé/MG. No afluente foi encontrado valores de ovos de helmintos na faixa de 2.891 a 88.848 ovos L-1, enquanto o efluente apresentou ausência de ovos, mostrando a alta eficiência do sistema de tratamento. Quanto ao lodo das lagoas, este apresentou elevada concentração de ovos viáveis variando entre 10,1% a 59,8%, fora dos padrões preconizados para a sua utilização na agricultura.

Assuntos

RESUMO

Sewage sludge is a residue from waste water treatment plants and vinasse is a main effluent from alcohol distilleries. The main differences between them are observed in the nitrogen (N) and potassium (K) contents. Sewage sludge is poor in K, and the vinasse in N. This research was carried out to evaluate sewage sludge and vinasse effects on the nitrogen contents of the plant-soil system and the effects of their application on planted-cane and 1st. ratoon-cane under field conditions, on a Typic Haplustox, in Pontal, State of São Paulo, Brazil, using the sugarcane cultivar SP81-3250. A randomized blocks experimental design was used with 13 treatments and three replications. The results were organized in a 3 × 2 × 2 factorial scheme (three residue forms, two application modes and two rates of N or K) and a control treatment (mineral fertilization). Sewage sludge provided the highest N plant contents and the highest residual N soil contents. Sewage sludge and vinasse can replace mineral fertilization for both planted-cane and 1st. ratoon-cane.

O lodo de esgoto é um resíduo obtido em Estações de Tratamento de Esgoto. A vinhaça constitui-se no principal efluente das destilarias de álcool. A principal diferença entre ambos está nos conteúdos de nitrogênio (N) e potássio (K), sendo o lodo de esgoto pobre em K e a vinhaça pobre em N. O objetivo deste trabalho foi avaliar o efeito do lodo de esgoto e da vinhaça sobre o nitrogênio no sistema solo-planta e os reflexos na produtividade da cana-de-açúcar por dois anos consecutivos. O experimento foi conduzido em um Latossolo Vermelho Amarelo Distrófico plintico, localizado no Município de Pontal, SP. A cultivar de cana-de-açúcar testada foi a SP81-3250. Os fatores de estudo foram três resíduos (lodo de esgoto, vinhaça e lodo de esgoto+vinhaça), dois modos de aplicação (linha de plantio e área total), duas doses (100 e 200% do N e K necessários à cultura) e um tratamento testemunha (adubação mineral). O lodo de esgoto proporcionou maior acúmulo de N na planta e maior teor residual de N no solo. A aplicação de lodo de esgoto e vinhaça na cultura da cana-de-açúcar pode substituir a adubação mineral, tanto para cana-planta quanto para cana-soca.

RESUMO

Sewage sludge is a residue from waste water treatment plants and vinasse is a main effluent from alcohol distilleries. The main differences between them are observed in the nitrogen (N) and potassium (K) contents. Sewage sludge is poor in K, and the vinasse in N. This research was carried out to evaluate sewage sludge and vinasse effects on the nitrogen contents of the plant-soil system and the effects of their application on planted-cane and 1st. ratoon-cane under field conditions, on a Typic Haplustox, in Pontal, State of São Paulo, Brazil, using the sugarcane cultivar SP81-3250. A randomized blocks experimental design was used with 13 treatments and three replications. The results were organized in a 3 × 2 × 2 factorial scheme (three residue forms, two application modes and two rates of N or K) and a control treatment (mineral fertilization). Sewage sludge provided the highest N plant contents and the highest residual N soil contents. Sewage sludge and vinasse can replace mineral fertilization for both planted-cane and 1st. ratoon-cane.

O lodo de esgoto é um resíduo obtido em Estações de Tratamento de Esgoto. A vinhaça constitui-se no principal efluente das destilarias de álcool. A principal diferença entre ambos está nos conteúdos de nitrogênio (N) e potássio (K), sendo o lodo de esgoto pobre em K e a vinhaça pobre em N. O objetivo deste trabalho foi avaliar o efeito do lodo de esgoto e da vinhaça sobre o nitrogênio no sistema solo-planta e os reflexos na produtividade da cana-de-açúcar por dois anos consecutivos. O experimento foi conduzido em um Latossolo Vermelho Amarelo Distrófico plintico, localizado no Município de Pontal, SP. A cultivar de cana-de-açúcar testada foi a SP81-3250. Os fatores de estudo foram três resíduos (lodo de esgoto, vinhaça e lodo de esgoto+vinhaça), dois modos de aplicação (linha de plantio e área total), duas doses (100 e 200% do N e K necessários à cultura) e um tratamento testemunha (adubação mineral). O lodo de esgoto proporcionou maior acúmulo de N na planta e maior teor residual de N no solo. A aplicação de lodo de esgoto e vinhaça na cultura da cana-de-açúcar pode substituir a adubação mineral, tanto para cana-planta quanto para cana-soca.