Enhancing Solid Waste Management: The Advantages of Biodecomposers and Composting: Part 1

The relentless growth of the global population and economic expansion exacerbates the escalating challenge of Urban Solid Waste (USW) management. This paper explores the efficiency of bio-decomposers in treating organic waste, contrasting with traditional landfill and incineration methods, and emphasizes the social and environmental benefits of composting. The social and environmental advantages of converting waste to compost are scrutinized, underscoring the role of composting in promoting soil health and reducing greenhouse gas emissions. By highlighting specific case studies and providing data-driven results, this study aims to advocate for broader adoption of these technologies to improve waste management and sustainability, using the potential of bio-decomposers and composting as sustainable alternatives that can transform waste into valuable resources.

Properly managing solid waste has become a crucial global issue as the world population grows and urbanization rapidly expands. Urban solid waste generation per capita increased from 348 kg to 379 kg annually between 2010 and 2019, therefore innovative waste management solutions have become urgent. In this context, domestic waste plays a significant role, as it is generated daily in residences and directly impacts the quality of community life. Current practices predominantly involve landfill disposal, contributing to environmental degradation and health risks. Domestic composting, which involves transforming organic waste into compost, reduces the volume of waste destined for landfills [1]. Thus, this paper discusses the potential of bio-decomposers and composting as sustainable alternatives that may transform waste into valuable resources (Panorama RSU, 2020).

Bio-decomposers: A sustainable solution for organic waste

Bio-decomposers offer a method to accelerate the decomposition of organic matter, converting waste into bio fertilizers and compost. These products are able to enrich soil, support agricultural activities, and reduce reliance on chemical fertilizers. The functionality of bio-decomposers in different settings, including residential areas, industrial restaurants, and community gardens, will be evaluated, focusing on their capacity to handle varying organic residues [2]. The principal function of Bio-composers is to provide a good composting of domestic organic waste. Composting, the natural process of organic waste decomposition, presents numerous advantages, such as reducing landfill use, mitigating methane emissions, and creating economic opportunities by selling compost. Despite its established benefits, the adoption of composting practices needs to continue being improved. This section reviews innovations in composting technologies, including community-based approaches and home composting systems, which have shown promising results in waste volume reduction and resource recovery [2].

State-of-the-art in organic waste management and composting technologies

Recent advances into organic waste management and composting technologies have significantly improved process efficiency, environmental sustainability, and economic viability. The synthesis of findings from thirteen critical studies in the field provides a holistic view of the current landscape and future directions.

Advanced composting technologies: The studies by Ghinea C, et al. [2] & Wei Y, et al. [3] emphasize the importance of advanced composting systems such as the Intelligent Bio-drying + Continuous Dynamic Trough (IB+CDT). These systems, along with optimized composting recipes, have been found to substantially reduce moisture content and enhance nutrient recovery, thereby improving the overall efficiency of the composting process.

Integration into waste management systems: Municipal Household Waste Management (MHWM), implemented through Waste Classification And Recycling (WCR), has long faced the challenge of recycling formalization [4,5] developed a stochastic tripartite evolutionary game to model the behavioral interaction of the three participants. They found that stochastic interference, cost reduction, and simplification of emergent rules for the WCR of MHWM, as well as the benefits of reward and performance improvement, have different incentive effects.

Nutrient recycling and environmental impact: Show that modern composting techniques may effectively recover nutrients while minimizing environmental impacts such as greenhouse gas emissions and leachate production [2,6-9].

Economic aspects and scalability: The studies by Vaverková MD, et al. [10] delve into the economic analyses of composting technologies. These studies suggest that these technologies cannot only be cost-effective but also scalable, thereby offering viable business models for organic waste management. This insight may be particularly useful for waste management professionals and policymakers.

Environmental and public health implications: Research has also emphasized the importance of minimizing environmental and public health impacts through advanced composting methods, which reduce leachate production and control pollutant emissions [11,12].

Biochar as a compost additive: Biochar has many potential uses owing to its unique physicochemical properties and attracts increasing attention as an additive in composting. Nguyen MK, et al. [13] and Guo XX, et al. [14] verified that the combined application of biochar and compost shows good performance as fertilizer; applying biochar improved compost maturity by promoting enzymatic activity and germination index.

Specific studies on composting efficiency: Additional detailed studies like those by Ghinea C, et al. [2] and Boldrin A, et al. [15] and provide insights into the optimization of composting processes through careful selection of composting materials and the establishment of practical composting recipes.

Innovations in composting modalities: Explorations into novel composting systems and their integration into urban and rural waste management systems display significant potential for substantial impact on waste reduction [15].This comprehensive narrative with specific citations provides a detailed overview of the state-of-the-art in bio-decomposers and composting technologies, drawing from a broad spectrum of recent research to highlight advancements, challenges, and potential directions.

These recent advancements in composting technologies have markedly increased efficiency, fostering environmental and economic benefits. Innovations such as Intelligent Bio-drying and optimized composting recipes enhance nutrient recovery and reduce environmental impacts. Economic analyses suggest cost-effectiveness and scalability, while integration into waste systems shows potential for global application. Adopting bio-decomposers is pivotal in transforming organic waste management into a sustainable practice.

The complete study will present data collected from implementing bio-decomposers in a residential block, an industrial restaurant, and through municipal waste management in Manaus. Comparative analysis will focus on the reduction of waste volume, improvement in waste processing time, and quality of the produced compost and biofertilizers. The complete work will focus on developing a bio-decomposer with its own feeding and aeration system that is simple to operate. To this end, this initial study presents the first stages of a batch composting process. Thus, this section will show the initial study with two small domestic compost bins (4L) set up, one with earthworm humus and the other without humus). A layer of sawdust was added to the bottom of each compost bin, and then earthworm humus was added to compost bin A (with humus). The compost bins were fed daily, with food waste from two residences containing three inhabitants. After introducing organic waste, a thin layer of sawdust was placed on the material, and the compost bin was closed. The waste was homogenized and weighed before being introduced into each compost bin. Once the total volume of the compost bin was completed, time was started to evaluate the degradation kinetics of organic matter.

200 g of gardening soil and 470 g of worm humus were added to the compost bin with worms, and then 150 g of chopped organic matter (fruit and vegetable remains) was added to each compost bin; this organic matter was covered with sawdust.

As this was an exploratory study, the experiments were carried out once, mainly because of the time it would require.

Organic fertilizer analysis

The compost bins were opened weekly for aeration and temperature and humidity measurements. At fortnightly intervals (every 15 days), small samples of the fertilizer produced (up to that moment) were collected and carried out in the laboratory, analyzing the macronutrient content: Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, and organic Carbon.In order to measure the temperature, a stick thermometer was used. It was inserted into three points of the compost bin (one point in the center and two at the opposite ends), and the temperature was given by the average of these three points.For humidity, a sample of fertilizer (with and without humus) was collected from the two compost bins, placed in separate containers, and previously weighed; their wet masses were weighed, then taken to an oven at 45°C for 12 hours, and weighed again (dry weight).

Monitoring home composting

The organic matter added to the compost bins consisted of peels and remains of banana, apple, papaya, mango, melon, carrot, coriander, pepper, potato, sweet potato, avocado, tomato, cucumber, cassava and lettuce. The material to be fed into the composters was previously chopped into particles with sizes between 3 and 5 cm, homogenized, divided into two parts, and added to the two composters so that they received the same material.

Figure 1 shows the evolution of the temperature of the compost bins and the ambient temperature over time. The compost bins were fed until day 35, and from day 70 onwards, the collection of fertilizer samples (in production) began for macronutrient analysis. It is observed that the highest temperatures were obtained between day 42 and day 68, where it remained around 40ºC; this period is called the thermophilic phase; from day 68 to day 98, the temperature tends to decrease, characteristic of the phase mesophilic, but there is still composting activity. From day 98 onwards, the temperature stabilizes and equals the ambient temperature, and the fertilizer maturation phase begins. This process is in accordance with the literature, such as the work presented by Meena, et al. [16]. The way the curves overlap shows the reproducibility of the process.

Figure 1: Temperature x composting days.

Heat production indicates that biological activity occurs in the mass of organic matter due to the metabolism of the microorganisms responsible for the degradation process. The temperature may vary according to the moisture content, aeration, the C/N ratio of the material mixture, the shape and size of the composting reactor (compost bin), and the ambient temperature. Composting occurs between the thermophilic and mesophilic phases.

Analysis of the organic fertilizer produced

Heat production indicates that biological activity occurs in the mass of organic matter due to the metabolism of the microorganisms responsible for the degradation process. The temperature may vary according to the moisture content, aeration, the C/N ratio of the material mixture, the shape and size of the composting reactor (compost bin), and the ambient temperature. Composting occurs between the thermophilic and mesophilic phases.

From the tables and figures, we realized that the magnesium, potassium, and organic carbon content, one of the main determining factors for good composting, was satisfactory. Despite this, the nitrogen content, another determining variable, was below the minimum required; therefore, fertilizer, although it can be used, would not be ideal for agriculture. A possible cause for this low nitrogen content may have been the amount of dry matter added to compost because this dry matter unbalances the carbon/nitrogen ratio, causing one of these components to increase while the other decreases in position.

The potassium levels were significant and satisfactory in both compost bins. It is worth remembering that, according to the Ministry of Agriculture and Livestock, potassium is the primary nutrient applied in Brazil, with 38%, followed by phosphorus, with 33%, and nitrogen, with 29%.

During the study, it was encountered and effectively addressed several challenges, underscoring the thoroughness of our research. Weekly openings of the compost bins for aeration and temperature and moisture measurements were conducted. Small samples of the produced compost were collected every two weeks for laboratory analysis of macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium) and organic carbon. The data showed satisfactory magnesium, potassium, and organic carbon levels, although nitrogen content was below the minimum standards for Class A organic fertilizers. Challenges such as ants and escaping worms were noted, and measures were taken to address these issues effectively. Furthermore, the work explores the role of public policy in supporting these technologies through incentives, awareness campaigns, and mandatory recycling programs.

In summary, biodecomposers and composting offer a practical solution to the escalating waste management crisis. They also contribute to environmental sustainability and public health improvement and bring people together around a single objective. Recommendations will include strategies for scaling up these technologies, enhancing public-private partnerships, and incorporating these practices into national waste management policies to maximize their impact.

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