Industrial Compost Research Articles

Performance of Biodegradable Biochar-Added and Bio-Based Plastic Clips for Growing Tomatoes.

Increasing quantities of waste from using conventional plastic in agriculture and horticulture is one of the most pressing issues nowadays. Conventional plastic accessories (e.g., mulching films, clips, pots, strings, etc.) are typically fossil-derived, non-biodegradable and difficult to recycle after their use. Therefore, there is a need for biodegradable and bio-based alternatives with similar properties to conventional plastics, which can be disposed of through degradation in water, soil or compost under specific conditions. This work investigated the properties and the performance of biodegradable biochar-added and bio-based stem and arch support clips. In addition, the investigated clips were composted with tomato residues during 16 week laboratory composting. The scope of this work included: (1) the production of stem and arch support clips in a pilot installation using injection molding technology, (2) an analysis of their chemical composition, biodegradability, disintegration and phytotoxicity, (3) an evaluation of their performance in the greenhouse cultivation of tomatoes and (4) an evaluation of the composting of the clips with on-farm organic waste as an end-of-waste management method. The stem support clips during industrial composting (58 °C) degraded at 100% after 20 weeks, whereas during home composting (30 °C) the degradation was slow, and after 48 weeks the maximum weight loss was 5.43%. Disintegration during industrial composting resulted in 100% fragmentation into particles with sizes less than 2 mm. Phytotoxicity tests demonstrated that the substrates after industrial and home composting did not have a negative effect on the growth of the test plants (i.e., mustard, wheat, cuckooflower). The biochar-added stem support clips proved to be satisfactory alternatives to conventional non-biodegradable, fossil-derived clips and can be disposed of through composting. However, more work is needed to determine the optimal conditions for composting to ensure rapid degradation of the clips in relevant environments.

A 24-Hour Waste Audit of the Neuro ICU during the COVID-19 Pandemic and Opportunities for Diversion.

We conducted a series of 24-hour waste audits in a 20-bed pod of a Neurosciences Intensive Care Unit (Neuro ICU) during the COVID-19 pandemic to 1) determine the unit's waste generation practices, 2) calculate associated downstream greenhouse gas emissions, and 3) identify opportunities to reduce landfill waste and emissions. We collected and weighed municipal solid waste, regulated medical waste, and mechanical recycling. We then compared the current, "as-is" practices to an ideal, "should-be" model which adds the alternative waste and reprocessing streams of industrial composting, advanced recycling, and sterilization followed by reuse. We found that the unit produced a total of 97.3 kg of waste over 24 hours, or 4.9 kg of waste per patient per day. 96.8% of this waste is currently landfilled. Emissions generated by processing landfill waste totaled 119.7 metric tons per year of CO2 equivalents. With the should-be sorting model, 24.7% of total waste produced by the unit could be diverted from landfills. Of this potentially divertible waste, 47.9% could undergo post-consumer industrial composting, 28.0% could undergo mechanical recycling, 22.2% could undergo advanced recycling, and 1.9% could undergo sterilization followed by reuse. Emissions from processing landfill waste in the should-be model totaled 110.6 metric tons per year of CO2 equivalents, representing a 7.7% decrease. These findings highlight the potential utility of alternate waste streams in this setting as well as the urgent need for complementary upstream waste reduction strategies to meaningfully reduce the Neuro ICU's landfill reliance and greenhouse gas emissions.

Comparison of composting factors, heavy metal immobilization, and microbial activity after biochar or lime application in straw-manure composting

Composting is an efficient way of disposing agricultural solid wastes as well as passivating heavy metals (HMs). Herein, equivalent (3%) biochar (BC) or lime (LM) were applied in rice straw and swine manure composting, with no additives applied as control group (CK). The results indicated that both the additives increased NO3­-N content, organic matter degradation, humus formation, and HM immobilization in composting, and the overall improvement of lime was more significant. In addition, the additives optimized the bacterial community of compost, especially for thermophilic and mature phase. Lime stimulated the growth of Bacillus, Peptostreptococcus, Clostridium, Turicibacter, Clostridiaceae and Pseudomonas, which functioned well in HM passivation via biosorption, bioleaching, or promoting HM-humus formation by secreting hydrolases. Lime (3%) as additive is recommended in swine manure composting to promote composting maturity and reduce HM risk. The study present theoretical guidance in improving composting products quality for civil and industrial composting.

Soft, environmentally degradable microfluidic devices for measurement of sweat rate and total sweat loss and for colorimetric analysis of sweat biomarkers

AbstractAdvanced capabilities in noninvasive, in situ monitoring of parameters related to sweat serve as the basis for obtaining real‐time insights into human physiological state, health, and performance. Although recently reported classes of soft, skin‐interfaced microfluidic systems support powerful functions in this context, most are designed as single‐use disposables. As a result, associated waste streams have the potential to create adverse environmental impacts. Here, we introduce materials and fabrication techniques that bypass these concerns through biodegradable microfluidic systems with a full range of features, including measurement of sweat rate and total loss, and colorimetric analysis of biomarkers. The key components fully degrade through the enzymatic action of microorganisms in natural soil environments, or in industrial compost facilities, to yield end products with beneficial uses as fertilizers and species to improve soil health. Detailed characterization of the constituent materials, the fabrication procedures, the assembly processes, and the completed devices reveal a set of essential performance parameters that are comparable to, or even better than, those of non‐degradable counterparts. Human subject studies illustrate the ability of these devices to acquire accurate measurements of sweat loss, sweat rate, pH, and chloride concentration during physical activities and thermal exposures.image

Development of a Sharing Concept for Industrial Compost Turners Using Model-Based Systems Engineering, under Consideration of Technical and Logistical Aspects

The trend of sharing concepts is constantly increasing, whether this may be for economic or environmental reasons. Consequently, numerous scientific research works have addressed the subject of sharing concepts. Many of these works have dealt with questions on the topic of sharing concepts itself, however, much less research has been dedicated to the question of how the sharing concept can be developed in the very first place. Thus, the purpose of this work was to systematically use systems engineering methods to develop a sharing concept for heavy-duty agricultural vehicles, while having a strong focus on technical and logistical aspects. Due to the multidisciplinary complexity of the sharing concept, a method from the field of model-based systems engineering, ARCADIA, was chosen. On ARCADIA’s top level, operational analysis was carried out to identify the key stakeholders. The next level, systems analysis, showed that the sharing model can be divided into three main processes: (1) data acquisition and preparation; (2) location planning; (3) and route planning. For these main processes, corresponding methods, algorithms and models were sought and compared against each other in the last level, logical analysis. It can be concluded that the ARCADIA method has provided a framework for evaluating the correlations and interrelationships between methods, algorithms and models at different levels to develop a sharing concept for compost turners from a technical perspective.

Lab-scale and on-field industrial composting of biodegradable plastic blends for packaging

Background: The acceptance of compostable plastic packaging in industrial composting plants is not universal despite available certification for compostability due to the persistence of compostable plastic residues reported by some industrial plants. This study aims to better understand this discrepancy by comparing the disintegration rate of two compostable plastic blends designed for rigid packaging (polylactic acid based) and soft packaging (polybutylene succinate based) between a controlled lab-scale test and an on-field test in an industrial composting plant. Methods: The thermophilic lab-scale disintegration test was conducted according to ISO 20200 in triplicates for 4, 8 and 12 weeks while the on-field test was conducted by exposing duplicate test material in the compost pile of an industrial composting plant in northern Germany, for three weeks. The mass change of the remaining test material >2mm was used as an indicator of disintegration. Results: The rigid packaging blend (1 mm thickness) retained on average 76.4%, 59.0% and 55.7% of its mass after 4, 8 and 12 weeks respectively in the lab-scale test. After exposure to industrial composting on-field, the remaining mass was 97.2% and 99.5%. The soft packaging blend (109±9 µm sample thickness) retained on average 45.4%, 10.9% and 0.3% of its mass after 4, 8 and 12 weeks respectively and 94.0% and 93.8% after exposure to industrial composting on-field. Conclusions: The results show a substantial difference in disintegration rates between the lab-scale and the on-field test after three to four weeks. The difference between the tests that might contribute significantly to the differing disintegration rates is the composition of the composting substrate. Besides the design and characteristics of the packaging itself, the composting substrate and thermophilic composting duration of individual plants are important to determine the suitability of treating compostable plastic packaging in industrial composting plants as well as inform potential solutions.

Home and community composts in Nantes city (France): quality and safety regarding trace metals and metalloids.

Home and community composting are key strategies for local organic waste management. The quality and safety of industrial composts are controlled, but those of home and community composts are not, and this could make them unsafe for use in kitchen gardens. Home (n = 20) and community (n = 41) composts, from urban and suburban areas including mildly Pb-contaminated allotment gardens, were analyzed for quality and safety regarding trace metals and metalloids (TMM) using mid-infrared Fourier transform spectrometry (FT-MIR) and portable X-ray fluorescence spectrometry, respectively. Home composts had a significantly higher Pb content (98mg.kg-1 ± 10mg.kg-1) than community composts (21mg.kg-1 ± 2mg.kg-1). Numerous home composts (85%) and a few community composts (17%) exceeded the organic farming thresholds for Pb (45mg.kg-1) and Zn (100mg.kg-1). The high mineral matter content and the relative abundance of chemical functions attributable to silicates (up to 35%) highly paralleled with TMM contents, mostly concentrated in the fine fraction. Co-inertia analysis highlighted strong and significant links between TMM contents and the whole chemical signature delivered by FT-MIR spectrometry. Pb-contaminated soil could be carried into home compost by green waste or by voluntary addition. Covariance analyses indicated that mineral matter and chemical functions only partly explained the variability in Pb content, suggesting a more complex combination of drivers. Community composting appears as a suitable local solution resulting in high-quality compost that complies with European organic farming regulations, while home composting from allotment gardens should be seriously evaluated to comply with such safety requirements.

(Invited) Biodegradable Organic Electronics: Degradation of Eumelanin Studied by Fluorescence Spectroscopy

A paradigm shift in resource exploitation and e-waste management is needed to promote sustainability in electronics. Reusing and recycling electronic devices is not only environmentally desirable but also economically viable and increasingly socially acceptable. A promising route to alleviate the environmental footprint of electronics is based on the use of abundant materials, novel production schemes involving non-toxic materials (through green chemistry processes), and eco-design of devices that includes environmentally acceptable end-of-life scenarios. Within this context, we integrate biosourced electro- and photo-active organic electronic materials, such as melanin, indigo, tannin and lignin derivatives (some of these readily available from biomass feedstock, abundant in Canada) into electronic and energy storage devices, such as transistors andbatteries. Biosourced organic electronic materials can be biodegradable. As such, they offer the opportunity for an environmentally benign device end-of-life scenario (as opposed to the present accumulation of e-waste).The melanin biopigment family serves as a prototypical environmentally benign class of materials for sustainable organic electronics and its powering elements. Among melanins, eumelanin is a brown-black type found in the human body, other mammals, reptiles, amphibians, and fishes as well as in invertebrates, such as cuttlefish and insects. Sepia Melanin (natural eumelanin) is a type of biosourced eumelanin extracted from the ink sac of cuttlefish. Synthetic eumelanin is commercially available (indicated here as Sigma eumelanin).We recently reported on encouraging studies on the biodegradability of eumelanin in industrial compost conditions (Di Mauro, E., Rho, D. & Santato, C. Biodegradation of bio-sourced and synthetic organic electronic materials towards green organic electronics. Nature Communications, https://doi.org/10.1038/s41467-021-23227-4); unfortunately, we did not report on intermediates of the biodegradation process. Insight on intermediates is expected to bring about an increase of the mineralization rate of eumelanin. Here, we will discuss possible oxidative degradation pathways of the biopigment eumelanin tin industrial compost conditions hrough fluorescence spectroscopy. Indeed, literature reports that oxidized (by oxidative cleavage of the quinoid structure of the indole moiety), naturally occurring eumelanin can give a lipofuscin-like yellow fluorescence.

Understanding the factors affecting the self-heating process of compost piles: Two-dimensional analysis

Industrial compost piles contain large volumes of bulk organic materials. Normally, there are two main heat generation processes—oxidation of cellulosic materials and biological activity within the compost pile. Biological heating occurs at a lower temperature range, but it may `kick-start' the oxidation reaction. Nevertheless, biological heating is desirable and is a key component in composting operations. However, there are cases when the temperature within the compost piles increases beyond the ignition temperature of cellulosic materials which can result in spontaneous ignition. This investigation considers the self-heating process that occurs in a compost pile using a two-dimensional spatially-dependent model incorporating terms that account for self-heating due to both biological and oxidative mechanisms. The variation of temperature distribution within different pile geometries is examined.

Characterization of greenhouse gas emissions and stable isotopic composition of ammonia during industrial composting process

Carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4) and ammonia (NH3) emitted during the composting of livestock and poultry waste are important gaseous atmospheric pollutants. However, most previous studies on compost-related anthropogenic emissions of these gases were based on small reactor composting. Our understanding of their in situ emissions during industrial composting remains extremely limited. In order to explore the influence of gas produced by industrial composting on regional environment, we monitored CO2, CH4, N2O and NH3 emissions during industrial composting for 19 days and characterized the isotopic composition of emitted NH3. On average, the emission rates of CO2, CH4, N2O, and NH3 during the composting cycle were 86.8 g CO2-C·d-1·m-2, 9.8 g CH4-C·d-1·m-2, 3.7 mg N2O-N·d-1·m-2 and 736.6 mg NH3-N·d-1·m-2, respectively. The contribution of CH4 to daily global warming potential (GWP) was the highest (65%), followed by CO2, NH3(indirect), and N2O. Moreover, ammonia emitted from industrial compost had a mean δ15N value of -11.6‰±1.2‰ (range: -21.8‰--7.2‰). Overall, this study provided useful information for understanding greenhouse gas emission dynamics and characterizing atmospheric NH3 sources during composting process in livestock and poultry breeding areas.

Use of industrial composts for the degradative disposal of pesticides

Destruction of pesticides using municipal solid waste (MSW) composting is one of the only rational uses for such waste. Voluminous production of compost featuring high heavy-metal-content, and negative costs of such material, make it possible to inexpensively implement certain large-scale processes at minimal cost. One of these is bioremediation of pesticides which, for various reasons (banned, expired, fall in demand, loss of activity, etc.), cannot be used as intended. An important aspect, however, is that not all pesticides are successfully degraded using MSW industrial compost. Mandatory checks are necessary to ensure that methods are effective for each active substance present in the materials undergoing remediation or destruction. This paper presents research results on the degradation of thiamethoxam, clothianidin, fludioxonil, and E-azoxystrobin using industrial composts produced at the ‘SPbGUP MPBO-2’ waste facility (Yanino region, St. Petersburg, Russia). It was shown that the compost contains microorganisms previously described in the literature as degraders of one or more of the pesticides analyzed. These include fungi of the genera Cladosporium and Phanerochaete. A number of degradative bacteria are also present, such as: Stenotrophomonas maltophilia; Bacillus subtilis and another Bacillus spp.; Pseudomonas; Achromobacter; Mesorhizobium; Microbacterium; and Pseudoxanthomonas. Degradation of thiamethoxam and clothianidin in compost was shown. A resistance to degradation, however, was noted with fludioxonil and E-azoxystrobin.

Influence of water ageing on the mechanical properties of flax/PLA non-woven composites

Flax fibres are widely used in the automotive sector to reinforce polyolefins, such as for dashboard and interior door panels. A promising option is poly-(lactid) (PLA), as it leads to higher mechanical properties and offers an additional end-of-life scenario following recycling: industrial composting. However, like other composite systems such as flax/polyolefin, flax/PLA composites are also sensitive to water. Here, a non-woven flax/PLA composite is aged under several conditions (50% RH/75% RH/98% RH/Immersion) until saturation. After ageing, all samples are reconditioned at 50% RH, and their residual properties are assessed. The presence of a critical relative humidity between 75 and 98% is highlighted, above which, increases in moisture content irreversibly decrease the composite's mechanical properties. After ageing at 98% RH and in immersion, tangent modulus was reduced by 23.0 and 33.8% and ultimate strength by 26.7 and 37.4%, respectively, compared to reference materials. This decrease is mainly due to microstructure evolution in the form of increasing porosity. This microstructure evolution is induced by the swelling of flax fibres, which generates high local stresses, above what PLA can withstand. As a result, micro-cracks appear in the matrix, responsible for reduction in mechanical properties.

Decentralized Composting of Food Waste: A Perspective on Scientific Knowledge

Composting has been demonstrated to be an effective and sustainable technology to treat a wide variety of organic wastes. A particular aspect of composting is the number of technological options that can be used, from full-scale plants to small composters. In this sense, the interest in composting at home or on a community scale is exponentially growing in recent years, as it permits the self-management of organic wastes and obtaining compost that can be used by the same producer. However, some questions about the quality of the obtained compost or the environmental impact of home composting are still in an early stage of development and provide little knowledge. In this review, the main points related to home and community composting are analysed in detail according to the current scientific knowledge by highlighting their advantages and possible drawbacks. Particularly, the composting process performance is analysed, with temperature stratification being one of the main problems related to small amounts of organic matter. Simultaneously, compost quality is determined using parameters such as stability and/or maturity, concluding that home compost can be similar to industrial compost in both aspects. However, sanitisation of home compost is not always achieved. Regarding its environmental impact, gaseous emissions, especially greenhouse emissions, are the most studied category and are generally low. Finally, the effects of pandemics on home composting are also preliminary commented, concluding that this strategy can be a good alternative to have cities that are more resilient.

Tailor-made compostable polyurethanes

Designed polyurethanes with degradable ester units all throughout the polymer backbone and quaternized ammonium units in the hard segment (tensile strength ∼30 MPa, elongation at break ∼1400%) show degradation in 35 days in industrial compost.

Effects of the Microbial Action Network in the Humification of Industrial Composting of Chicken Manure

Effects of the Microbial Action Network in the Humification of Industrial Composting of Chicken Manure

Effects of the Microbial Action Network in the Humification of Industrial Composting of Chicken Manure

Effects of the Microbial Action Network in the Humification of Industrial Composting of Chicken Manure

Development of a Sharing Concept for Industrial Compost Turners Using Model-Based Systems Engineering, Under Consideration of Technical and Logistical Aspects

Development of a Sharing Concept for Industrial Compost Turners Using Model-Based Systems Engineering, Under Consideration of Technical and Logistical Aspects

Field studies on the deterioration of microplastic films from ultra-thin compostable bags in soil

In recent years, some countries have replaced single-use plastic bags with bags manufactured from compostable plastic film that can be used for collecting food wastes and composted together with the waste. Because industrial compost contains undeteriorated fragments of these bags, application to field soil is a potential source of small-sized residues from these bags. This study was undertaken to examine deterioration of these compostable film microplastics (CFMPs) in field soil at three different localities in Italy. Deterioration of CFMPs did not exceed 5.7% surface area reduction during the 12-month experimental period in two sites located in Northern Italy. More deterioration was observed in the Southern site, with 7.2% surface area reduction. Deterioration was significantly increased when fields were amended with industrial compost (up to 9.6%), but not with home compost. Up to 92.9% of the recovered CFMPs were associated with the soil fungus Aspergillus flavus, with 20.1%–71.2% aflatoxin-producing isolates. Application of industrial compost resulted in a significant increase in the percentage of CFMPs associated with A. flavus. This observation provides an argument for government regulation of accumulation of CFMPs and elevation of hazardous fungi levels in agricultural soils that receive industrial compost.

Industrial Composting of Sewage Sludge: Study of the Bacteriome, Sanitation, and Antibiotic-Resistant Strains.

Wastewater treatment generates a huge amount of sewage sludge, which is a source of environmental pollution. Among the alternatives for the management of this waste, industrial composting stands out as one of the most relevant. The objective of this study was to analyze the bacterial population linked to this process and to determine its effectiveness for the reduction, and even elimination, of microorganisms and pathogens present in these organic wastes. For this purpose, the bacteriome and the fecal bacteria contamination of samples from different sewage sludge industrial composting facilities were evaluated. In addition, fecal bacteria indicators and pathogens, such as Salmonella, were isolated from samples collected at key stages of the process and characterized for antibiotic resistance to macrolide, β-lactam, quinolone, and aminoglycoside families. 16S rRNA phylogeny data revealed that the process clearly evolved toward a prevalence of Firmicutes and Actinobacteria phyla, removing the fecal load. Moreover, antibiotic-resistant microorganisms present in the raw materials were reduced, since these were isolated only in the bio-oxidative phase. Therefore, industrial composting of sewage sludge results in a bio-safe final product suitable for use in a variety of applications.

Features of the industrial composting implementation of organic waste in St. Petersburg

Relevance of the work is due to a lack of developed infrastructure in Russia for processing organic waste by composting to obtain high-quality organic fertilizer. The authors reviewed the Best Available Techniques (BAT) reference books for industrial composting. Based on the literature review, visiting the solid waste landfill and the waste processing station, two technologies were proposed for consideration: open and closed composting of organic waste. The performed ecological and economic analysis has appealed that the most effective option for processing organic waste is the use of closed composting technology in the aerobic bioreactor. The article substantiates the expediency of creating an infrastructure for industrial composting of organic waste.