ABSTRACT Proper waste management is a major worldwide concern; waste is disposed of directly into the environment, affecting water, soil and air quality. The development and production of green energy sources is strongly encouraged in modern society. The aim of this study, in accordance with Sustainable Development Goals (SDGs) 1, 2 and 7 of the 2030 Agenda of the UN, is to combine the correct disposal of animal waste with the generation of energy to mitigate the energy insecurity of families in an extremely vulnerable semi-arid region in the north-east of the country using biodigesters. To this end, a conceptual proposal was drawn up for a low-cost, easy-to-maintain and easy-to-use biodigester. A small-scale prototype was used to assess its operation by evaluating the main factors that affect biogas production (pH, temperature and the biomass properties: total solids, fixed solids, volatile solids, concentration of volatile fatty acids and C/N ratio). Evaluation of the test prototype gave satisfactory results that corroborate other studies and make it possible to propose an economically viable and efficient full-scale biodigester for biogas production. concern environment water quality society study SDGs (SDGs 1 203 UN semiarid semi arid northeast north east biodigesters end lowcost, lowcost low cost, cost low-cost easytomaintain easy maintain easytouse use smallscale small scale pH, pH (pH properties solids CN C N ratio. ratio . ratio) fullscale full 20

RESUMO A agricultura familiar busca utilizar práticas agrícolas menos agressivas, entretanto existem poucas máquinas adequadas à realidade deste segmento, isso tem levado ao uso de práticas tecnicamente incorretas, que vem contribuindo para o empobrecimento, compactação e desertificação dos solos agrícolas. Diante disso, as semeadoras puncionadoras apresentam-se como uma possibilidade promissora para realizar o processo de semeadura para agricultura familiar, visto que realiza a distribuição de semente de forma pontual, contribuindo para a menor mobilização do solo e consequente preservação e conservação da estrutura do mesmo. O objetivo do trabalho foi avaliar a qualidade de distribuição de sementes por uma semeadora puncionadora para a agricultura familiar. O ensaio foi realizado em um solo classificado como Argissolo Vermelho-amarelo. Foi utilizada a estatística descritiva para avaliar a qualidade da distribuição de sementes pelo sistema puncionador. O Controle Estatístico do Processo foi adotado para avaliar o controle de qualidade do processo de distribuição de sementes. Os resultados demostraram que a semeadora puncionadora apresentou desempenho semelhante à semeadora de precisão pneumática, obtendo 90,2% de espaçamentos aceitáveis, sendo uma alternativa viável para realizar o processo de semeadura para a agricultura familiar, fato comprovado pelo estudo do CEP que indicou a adequação do processo de semeadura aos padrões de qualidade, pois obteve 88,4% de precisão no processo, possibilitando a elevação da qualidade de semeadura. O sistema puncionador proporcionou menor mobilização do solo quando comparado ao sulcador de disco e semeadora manual, mostrando-se como uma solução eficaz para a agricultura conservacionista.

ABSTRACT Family farming seeks to use less-aggressive agricultural practices, however, there is little machinery available that is suitable for the reality of this sector. This has led to the use of technically incorrect practices, which have contributed to the impoverishment, compaction and desertification of agricultural soils. Punch seeders are seen as a promising alternative for carrying out sowing in family farming, as they employ localised seed distribution with less disturbance of the soil and the consequent preservation and conservation of its structure. The aim of this study was to evaluate the quality of seed distribution by a punch seeder used in family farming. The experiment was carried out in a soil classified as a Red-Yellow Argisol. Descriptive statistics were used to evaluate the quality of seed distribution by the punch system. Statistical Process Control was adopted to evaluate quality control in the seed distribution process. The results showed that the performance of the punch seeder was similar to that of the precision pneumatic seeder, with 90.2% acceptable spacing. As demonstrated by the SPC study that showed the process to be compatible with quality standards, the punch seeder is therefore a viable alternative in the sowing process for family farming, since an improvement in sowing quality, with a precision of 88.4% was obtained. The punch system resulted in less soil disturbance when compared to the disc harrow and manual seeder, and proved to be an effective solution for conservation agriculture.