Determinacion de indicadores de madurez en la produccion de composta (Spanish text).

摘要

The management and disposal of municipal and industrial biosolids is known to be a critical issue to modern societies. Compost production using biosolids has been used as an alternative for the biosolids treatment and disposal. Several methods were compared to evaluate compost maturity, using biosolids obtained from the Barceloneta Wastewater Treatment Plant with triturated sugarcane (US 67-22-2) as substrates. Parameters used to characterize and evaluate compost maturity were: Carbon/Nitrogen ratio (C/N), cationic exchange capacity (CEC), pH, temperature, moisture content, CO₂ and CH ₄ production, O₂ consumption, germination tests and changes in microbial populations. Composts were prepared using Carbon/Nitrogen ratios (20:1, 25:1 and 30:1) and were placed in an isolated reactor to monitor changes through the composting process. Composts were maintained in the reactor for 15 days, and were monitored during the composting process (60 days). The 30:1 C/N ratio showed the best composting characteristics achieving a higher maturity level than the two other ratios (20:1 and 25:1). The C/N ratio, pH and moisture content decreased during the composting cycle. The gas analysis inside the reactor showed a high correlation between the production of CO₂ and the consumption of O₂. The CH₄ percent in the reactor remained constant during the decomposition process. Once the compost was retired from the reactor (day 15), none of the samples showed maturity characteristics, but stability characteristics were evident in the 30:1 samples. The biological essays using microbial populations and germination tests were efficient presenting the difference between the C/N ratios and the stages during the composting process.