![]() ![]() All the products obtained at 183 d were within the parameters to be considered as organic fertilizers, but the SC product transformed into an organic fertilizer fastest and had least water usage. The VC product had the highest GI values. The CP product had higher pH, EC, and EUA values than both VC and SC. All three systems reduced the C/N ratio to less than 15/1. The temperature ranged between 20 and 34 ☌ in VC and SC, while in CP between 20 and 61 ☌. ![]() The variables evaluated showed significant differences between time and treatment. Temperature, total N (Nt), organic C (OC), C/N ratio, pH, enzymatic urease activity (EUA), germination index (GI) and electrical conductivity (EC) were measured throughout the time of study. A mixture of bovine manure and sawdust was subjected to each of three systems for 183 d. The objective of the present study was to compare over time physical, chemical and enzymatic parameters of OW transformed as vermicomposting (VC), semicomposting (SC) and composting (CP) for elaboration of organic fertilizers. ![]() Supporting resource recovery from wastewater will need a step-wise approach to address a range of constraints to deliver a high rate of return in direct support of Sustainable Development Goals (SDG) 6, 7 and 12, but also other Goals, including adaptation to climate change and efforts in advancing “netzero” energy processes towards a green economy.Organic wastes (OW) of diverse nature must be subjected to controlled decomposition processes to avoid risks of contamination and obtain products useful for agriculture. These estimates and projections are based on the maximum theoretical amounts of water, nutrients and energy that exist in the reported municipal wastewater produced worldwide annually. At the energy front, the energy embedded in wastewater would be enough to provide electricity to 158 million households. Beyond nutrient recovery and economic gains, there are critical environmental benefits, such as minimizing eutrophication. The full nutrient recovery from wastewater would offset 13.4% of the global demand for these nutrients in agriculture. Among major nutrients, 16.6 Tg (Tg = million metric ton) of nitrogen are embedded in wastewater produced worldwide annually phosphorus stands at 3.0 Tg and potassium at 6.3 Tg. Wastewater production globally is expected to increase by 24% by 2030 and 51% by 2050 over the current level. The study estimates suggest that, currently, 380 billion m3 (m3 = 1,000 L) of wastewater are produced annually across the world which is a volume fivefold the volume of water passing through Niagara Falls annually. ![]() Based on the synthesis of wastewater data, this study provides insights into the global and regional “potential” of wastewater as water, nutrient and energy sources while acknowledging the limitations of current resource recovery opportunities and promoting efforts to fast-track highefficiency returns. There is a proactive interest in recovering water, nutrients and energy from waste streams with the increase in municipal wastewater volumes and innovations in resource recovery. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |