Recycling Of Organic Wastes Research Articles

Structural diversity and efficacy of culturable cellulose decomposing bacteria isolated from rice-pulse resource conservation practices.

The diversity of cellulolytic bacteria from the rice-pulse system can be sourced for identification of efficient cellulose decomposing microbial strains. In the present study, the abundance, structural diversity, and cellulolytic potential of the culturable bacterial community were studied in 5-year old rice-pulse system under different resource conservation technologies. Higher cellulose (68% more) and xylanase (35% more) activities were observed under zero tilled soil. The populations of cellulolytic bacteria were significantly higher (44%) in zero tillage (ZT) treatment than those of conventional practice. Results revealed that the cellulolytic bacterial diversity was found to be significantly higher under ZT practice, but the present population may not be sufficient for effective recycling of organic wastes in this system. Out of 290 bacterial isolates, 20 isolates had significantly higher cellulolytic activities, of which the top three superior isolates were received from ZT practice. The cellulolytic bacterial diversity based on 16S rDNA sequencing data revealed that the Firmicutes was the most dominant phyla and the Bacillus spp. were the common genus, the observation also showed that there were 17 different haplotypes were recorded among 20 isolates of cellulolytic bacteria. The present findings indicated that long-term ZT in the rice-pulse system could be a unique source for efficient cellulose decomposing bacteria and further the efficient bacterial strains isolated from this system can be used as efficient bioinoculants for in situ as well as ex-situ decomposition of rice straw particularly in conservation agriculture.

Influence of Pyrolyzed Grape-Seeds/Sewage Sludge Blends on the Availability of P, Fe, Cu, As and Cd to Maize

Current intensive agricultural practices, although highly successful in terms of production, have been found to be environmentally unsustainable. One of the crucial approaches to increase agricultural sustainability is the recycling of organic wastes, since these materials often contain many beneficial nutrients for soil and agriculture. Recently, pyrolytic conversion of biodegradable waste into charred material has gained global attention as an amendment to recycle nutrients while improving soil health. Increasing interest in the beneficial applications of pyrolyzed biomass has expanded multidisciplinary areas for science and engineering. The fertilizers used in this study were prepared by pyrolyzing mixtures of two abundant residues in Mediterranean areas: grape seeds and sewage sludge, in different proportions (100% GS, 75% GS-25% SS, 50% GS-50% SS, 25% GS-75% SS, 100% SS). In addition, fresh sludge was mixed with pyrolyzed grape seeds and included as an additional treatment. In this study, the positives and negatives of the application of biochars on agronomic potential and environmental risk have been addressed, taking into account P, Zn, Cu, Fe, As and Cd. In order to choose the best mixture, it is necessary to find a compromise between maximizing the beneficial elements that are translocated to the plant crop, as well as reducing the elements that are leached. Results of a 6-week greenhouse study indicated that the unpyrolyzed sludge mixture contained the largest amount of available nutrients Fe, Cu and P. In agreement, this treatment mixed with a Chromic Luvisol soil (40 ton/ha) increased the uptake of these elements in corn (Zea mays L.—LG ambitious). The yield also increased by 60% in this treatment. However, this mixture also contained more contaminants (As, Cd) which were extracted with Ammonium Bicarbonate-DTPA. According to our results, the treatments where grape seeds and sewage sludge were mixed at 50% and then pyrolyzed exhibited the optimal compromise between efficiency (nutrients uptake) and tolerable levels of potentially toxic elements in leachates.

Enhancing nutrient recycling from excreta to meet crop nutrient needs in Sweden \u2013 a spatial analysis

Increased recycling of nutrient-rich organic waste to meet crop nutrient needs is an essential component of a more sustainable food system. However, agricultural specialization continues to pose a significant challenge to balancing crop nutrient needs and the nutrient supply from animal manure and human excreta locally. For Sweden, this study found that recycling all excreta (in 2007) could meet up to 75% of crop nitrogen and 81% of phosphorus needs, but that this would exceed crop potassium needs by 67%. Recycling excreta within municipalities could meet 63% of crop P nutrient needs, but large regional differences and imbalances need to be corrected to avoid over or under fertilizing. Over 50% of the total nitrogen and phosphorus in excreta is contained in just 40% of municipalities, and those have a surplus of excreta nutrients compared to crop needs. Reallocation of surpluses (nationally optimized for phosphorus) towards deficit municipalities, would cost 192 million USD (for 24 079 km of truck travel). This is 3.7 times more than the total NPK fertilizer value being transported. These results indicate that Sweden could reduce its dependence on synthetic fertilizers through investments in excreta recycling, but this would likely require valuing also other recycling benefits.

Design and Construction of a Shredding Machine for Recycling and Management of Organic Waste

Design and Construction of a Shredding Machine for Recycling and Management of Organic Waste

Environmental entrepreneurship: characteristics of organization and development

The growing awareness of environmental issues, such as the accelerated depletion of natural resources and declines in the quality of the environment, has led to the emergence of the concept of balanced (sustainable) development, which implies continual coordination with an equal focus on the following three key components of development – economic, social, and environmental. The purpose of this paper is to analyze some of the key characteristics of the development and organization of environmental entrepreneurship. The authors explore in detail the concept of environmental entrepreneurship. An expert survey was conducted to determine some of the key ideas for the development of environmental entrepreneurship, as well as some of the key prospects for integrating environmental aspects into entrepreneurial activity as a whole. Among the key areas for the development of environmental entrepreneurship listed in the paper are production of organic output, environmental construction, environmental tourism, and waste management and recycling. The authors provide an in-depth insight into some of the key principles and lines of activity on each of the areas mentioned.

Green potential of Pleurotus spp. in biotechnology.

BackgroundThe genus Pleurotus is most exploitable xylotrophic fungi, with valuable biotechnological, medical, and nutritional properties. The relevant features of the representatives of this genus to provide attractive low-cost industrial tools have been reported in numerous studies to resolve the pressure of ecological issues. Additionally, a number of Pleurotus species are highly adaptive, do not require any special conditions for growth, and possess specific resistance to contaminating diseases and pests. The unique properties of Pleurotus species widely used in many environmental technologies, such as organic solid waste recycling, chemical pollutant degradation, and bioethanol production.MethodologyThe literature study encompasses peer-reviewed journals identified by systematic searches of electronic databases such as Google Scholar, NCBI, Springer, ResearchGate, ScienceDirect, and ISI Web of Knowledge. The search scheme was divided into several steps, as described below.ResultsIn this review, we describe studies examining the biotechnological feasibility of Pleurotus spp. to elucidate the importance of this genus for use in green technology. Here, we review areas of application of the genus Pleurotus as a prospective biotechnological tool.ConclusionThe incomplete description of some fungal biochemical pathways emphasises the future research goals for this fungal culture.

Soil-plant nitrogen pools in nectarine orchard in response to long-term compost application

The search for sustainable source of N, the need of soil organic matter restoration, along with the call for recycling of organic wastes has led to a rise of the use of organic fertilizers. The aim of the present experiment was to evaluate: the effectiveness of compost application as a N fertilizer, the impact on N distribution in soil and plant and on tree performances, in a long-term experiment (14 years).The study was carried out in the Po valley, Italy and, since orchard planting (2001), the following treatments were applied: 1. unfertilized control; 2. mineral fertilization; 3. compost at a rate of 5 t DW ha−1 yr−1; 4. compost at a rate of 10 t DW ha−1 yr−1. Soil total N, potentially mineralizable, microbial and extractable N were higher in compost in comparison to mineral (fertilizer). The effect was found both in the row and in the inter-row and the rise of N fractions was evident in the shallowest soil layer of the row. Soil mineral, potentially mineralizable N was increased by mineral (11.1 mg kg−1) and compost 10 (12.4 mg kg−1) fertilization compared with control (6.7 mg kg−1). Vegetative growth and yield were increased in trees treated with mineral and compost 10; moreover, these plants were able to recycle (66.1 and 70.5 kg ha−1 yr−1, respectively) and remobilize (41.5 and 48.7 kg ha−1 yr−1, respectively) a higher amount of N than those of control and compost 5. In conclusion, organic fertilization strategy promoted the buildup of soil N reserve, meaning a capacity of the ecosystem to sequestrate N. The application of compost 10 showed a similar effect on plant growth and production as mineral fertilization, but introduced the advantage of the use of a cheap, renewable waste material, providing a new insight on N fertilization management.

Recycling of Organic Wastes in Agriculture: An Environmental Perspective

Inadequate organic waste management leads to a plethora of problems such as environmental pollution, eutrophication, esthetic damage to urban landscape, greenhouse gases emission and effects on human health. Unwise and non-scientific disposal of wastes not only poses a grave threat to environmental quality but also results in loss of economic value of wastes. Since organic wastes are an abundant pool of organic matter and valuable plant nutrients, agricultural recycling of these wastes appears to be a promising alternative enabling value addition and their resourceful utilization. Land application of organic wastes stabilized through techniques such as composting, vermicomposting and anaerobic digestion yielding excellent organic fertilizer like compost augments soil fertility and crop yield. Additionally, the practice incorporates indirect environmental benefits such as reduced greenhouse gas emissions, land conservation due to reduced landfilling of wastes and substitute to chemical fertilizers. Economically also, agricultural utilization of organic wastes reduces the cost of landfilling, transportation of wastes, imports and production cost of chemical fertilizers and opens avenues for rural employment. However, effective utilization of organic wastes for agricultural purposes requires thorough and strict risk assessment to prevent the adverse effects of contaminants like heavy metals, persistent organic pollutants to ensure agro-environmental sustainability. The present article aims to enlist the positives and negatives associated with this practice enabling to devise an approach or strategy deriving maximum environmental and economic benefits.

Waste Composition Evaluation for Solid Waste Management Guideline in Highland Rural Tourist Area in Thailand

This study investigated municipal solid waste generation rate and its compositionincluding the level of knowledge, attitude and practice on municipal solid waste (MSW) management of highland rural tourist area in Chiang Rai Province, Mae Salong Nok Sub-district, Thailand in order to propose the guidelines for effective MSW in rural tourist areas. Samples of MSW were collected during weekdays and several weekends, and separated into 4 categories: general,recyclable, organic and hazardous waste. About 40 % of the MSW consisted of organic waste; plastic bags were widely present, comprising more than 60 % of the mass of the general waste group. Level of knowledge, attitude and practice(KAP) on MSW was evaluated using questionnaires. While respondents scored 80 % and 76 %, respectively, on their level of knowledge of, and attitude to MSW, practice fell far short at only 37 %. The results led to a recommendation to strengthen waste separation at source, implement waste reduction and recycling concepts to reduce the volume of plastic bags, and introduce composting of food waste. The study also highlights economic and financial benefits of waste recycling. Additional value-added could be derived from the organic waste recycling program by promoting production of bioextracts and compost at household level, in order to reduce the amount of organic wastes and carbon emissions. The general and recyclable wastes could also be converted to energy as refuse-derived fuel 2 (RDF-2); the estimated average heating value of this RDF-2 was 23.56 MJ kg-1. To sustain MSW management in tourist areas, environmental education and environmental awareness campaigns are needed, using the appropriate local languages for communication, and introduction of a fairer system based on the polluter-pays principle for the business sector.

Why adoption is slow despite promising potential of biogas technology for improving energy security and mitigating climate change in Sri Lanka?

Despite multiple economic, environmental and health benefits of biogas and governmental support to scale up biogas technologies, the rate of biogas adoption has been slow in many developing countries. Although technical barriers in biogas technologies have been mostly addressed, there are persisting gaps in knowledge about the role of administrative (regulatory) and market-based policy instruments in the waste-to-energy value chain for facilitating biogas adoption. Therefore, using the case of Sri Lanka, this study investigates policy instruments along the waste-to-energy value chain that affect biogas technology adoption. Additionally, a consistent analytical framework is developed for simultaneously assessing technical and economic potentials as well as environmental impacts of biogas adoption at large scales. Quantitative assessments are complemented with qualitative assessments including key expert interviews. The findings indicate that biogas energy potential from organic waste recycling is 29–42 PJ which accounts for 16–23% of the household energy demand. Biogas technology adoptions also offset 3.9–4.8 million tons of CO2 equivalent gases (or 8.6− 10.8% of nationwide GHG emissions). Despite considerable technical potential and positive environmental externalities, biogas adoptions in Sri Lanka are mainly occurring through administrative enforcement rather than market-based incentives. The ways and impacts of introducing market-based instruments to increase the investment attractiveness of the biogas technology are discussed.

Lignite Gasification in Thermal Steam Plasma

Recycling of organic waste is an increasingly hot topic in recent years. This issue becomes even more interesting if such processing leads to a source of hydrogen or syngas for fuel production. A process of high-temperature decomposition of lignite was studied on the plasma gasification reactor PLASGAS, where water-stabilized plasma torch was used as a source of high-enthalpy plasma. The plasma torch power was 120 kW and allowed heating of the reactor to more than 1000 °C. The material feeding rate in the gasification reactor was 30 or 60 kg per hour that is comparable to a small industrial production process. The efficiency evaluation of the thermal decomposition process was performed. Energy balance of the process was carried out as well as an influence of the lignite particle size and the addition of methane (CH4) on the synthesis gas composition. The ratio H2/CO was in the range of 1.5–2.5 depending on the experimental conditions.

Design opportunities for organic waste recycling in urban restaurants.

This research project focuses on the problem of organic (or food waste) waste recycling in Flanders, Belgium. Here, the total amount of organic waste produced annually by restaurants is estimated at 166,000 tonnes. Despite being in the evolution towards a circular economy, more than 61% of the restaurants do not collect organic waste separately from residual waste. Within the research, this problem was explored from a human-centred perspective by analysing existing food-waste collection and processing equipment, and by observing the kitchen workflow and interior design of different urban located restaurants. The aim of the research was to identify design opportunities to integrate and optimize the collecting and recycling of food waste in restaurants. In sum, it was possible to distinguish different elements, variables and constraints across the various restaurants related to the disposal and handling of food waste in the kitchen and in the clearing area during the shift. The paper concludes with design requirements for the optimization of food-waste recycling systems, which are related to the cost of the system, the effort that is needed, the lack of space, potential bad odour, hygiene matters, integration in the workflow, organization of the workspace and use of additional resources and energy.

Waste-to-Energy Development Using Organic Waste Recycling System (OWRS): A Study Case of Giwangan Market

Food wastes were the major problem in the traditional market since there were inadequate organic waste processing facilities provided. Most of all these wastes end into the landfill, and the wastes have high energy recovery potential to be generated with a scientific treatment. This research proposes the waste-to-energy implementation planning for energy harvesting from the organic waste generation of the Giwangan traditional market, Yogyakarta Province, Indonesia by using organic waste recycling system (OWRS) as a pretreatment technology. The proposed recycling system consists of two major processes such as dewatering process and pyrolysis process. The dewatering process aims to decrease the water content and remind solids, where the pyrolysis process aims to convert solids into charcoals. The product of dry organic material from the OWRS system becomes the input for gasification to produce synthetic gas as fuel on the internal combustion engine. Pretreatment process by using OWRS system can increase the calorific value of food waste by 5,815.33 kcal/kg, and it can remove the water content of fruit waste and vegetable waste up to 99.25% and 99.06% respectively. The liquid product from OWRS system generates the C/N ratio with value 4.06. The implementation of OWRS system which produces the updraft for gasifier process can generate the energy by 5.14 kW and achieves the efficiency by 11% of electrical power from the total organic waste generated by Giwangan  traditional market.

Recycling of Organic Waste for its Potential to be Used as Fertilizer

Recycling of Organic Waste for its Potential to be Used as Fertilizer

Konya‘da Sürdürülebilir Kentsel Yeşil Alanlar için Geri Dönüşüm Modeli

Kentsel yeşil alanlar, kentlerin sürdürülebilirliğini sağlamak için kapsamlı bir araç olabilir. Yeşil alanların planlama, tasarım, uygulama, bakım ve işletme süreçlerinde sürdürülebilir olması, kentlerin de sürdürülebilir gelişmesine katkı sağlamaktadır. Yeşil alanların sosyal, ekonomik ve ekolojik açıdan sürdürülebilir olmasını sağlamanın pek çok yolu bulunmaktadır. Bunlar arasında geri dönüşüm ve yeniden değerlendirme kapsamında kompost yapımı ve kullanımı yer almaktadır. Kentsel yeşil alanlarda periyodik bakım sonucunda ortaya çıkan atıklar, diğer atıklarla birlikte katı atık depolama alanında bertaraf edilmektedir. Ancak organik atıkların kompost yapımında kullanılması ile hem geri dönüşüm sağlanıp hem de yeşil alanların periyodik bakım masrafları azaltılarak yeşil alanların sürdürülebilir olması sağlanabilir. Bu çalışmanın amacı yeşil alanlarda ortaya çıkan organik atıkların kompost yapılarak yeşil alanlarda kullanımı ile geri dönüşüm ve yeniden değerlendirme fikrini geliştirmektir. Bu amaç doğrultusunda Konya‘daki yeşil alanlarda ortaya çıkan organik atıklardan kompost yapılması ve gübre yerine kullanılması için bir model önerilmiştir. Böylece tasarım, uygulama ve bakım masrafları çok yüksek olan yeşil alanların maliyetleri azalacak ve kendi içinde sürdürülebilir olacaktır. Kentsel yeşil alanların sürdürülebilir olması da Konya‘nın kentsel sürdürülebilirliğine katkı sağlayacaktır.

The role of management instruments in the diversion of organic municipal solid waste and phosphorus recycling

Organic waste, which contains essential plant nutrients such as phosphorus, constitutes 30%–50% of municipal solid waste in developed countries. Unfortunately, much of this resource is buried in landfills or incinerated. Many jurisdictions have, therefore, adopted the diversion of organic waste and the recycling of nutrients as policy goals. We used data sets from Europe and Ontario, Canada, to explore the impact of socio-economic and management factors on the rates of organic waste diversion and examined the effect of this diversion on phosphorus recycling. Organic diversion rates were highly correlated with income in Europe and with infrastructure, such as source-separated organic waste collection, in Ontario. Significant correlations were also observed between diversion rates and the use of policy instruments such as economic incentives, legislative organic waste bans, and curbside bag limits. We estimated that 39%–63% of the phosphorus in diverted organics is returned to arable land. Ultimately, we found that although socio-economic factors influence the success of organic waste diversion, policies, accessible infrastructure, economic incentives, and legislative requirements can be leveraged to improve the recycling rate of organic waste and the nutrients they contain.

Use of digestate as an alternative to mineral fertilizer: effects on growth and crop quality

ABSTRACTNowadays, the recycling of organic wastes represents a key factor for improving soil and crop quality with socio-economic and environmental benefits. In recent years, the production of digestate significantly increased with a crescent need to be sustainable disposal. The use of digestate as soil amendment has been widely studied but few researches evaluated the digestate effects on crop quality. Since it has been proven that digestate increased soil fertility, we hypothesized that it could increase crop quality as organic fertilizers do. To verify this hypothesis, we analyzed the effects of two digestates on Cucumber quality. Cucumber was chosen because it is an important old crop used worldwide as fresh food, and in cosmetic and pharmaceutic industries. Results showed that digestates increased its content of phenols and flavonoids with antioxidant activity. Neohesperidine and hesperitin with well-known antioxidant, anti-inflammatory and anti-carcinogenic properties as well as naringin and narirutin with the power of reducing the risk of atherosclerosis and cardiovascular complications were manifested only in digestate amended cucumbers. These results highlighted the potentiality of digestates not only as crop growth promoter but also as phytochemical inducers representing a good option for the production of high-quality food with reduced chemical mineral fertilizer inputs.

Recycling of domestic organic waste with the use of composting and vermicomposting

The increase of the world population associated to the concentration of this population in urbanized environments has caused the growth of the production of residues of organic solids, that in most of the times are discarded in inadequate places that can pollute the environment. Another factor that is also related to population growth is the demand for more food, mainly agricultural products, which need different inputs, such as fertilizers to increase productivity. Given this context, it is essential to use technologies that allow the recycling of nutrients from organic waste, which have the potential to condition soils and fertilize agricultural crops. This work has the objective of evaluating two already consolidated technologies for recycling solid organic waste, such as composting and vermicomposting, implanted in compact systems. Among these feasible systems were evaluated the humic compounds and the slurries generated, the parameters being evaluated the assimilable phosphorus (P), the active acidity, organic matter and the organic carbon. The results obtained indicate that the vermicompost presents a higher production of humic compound and less of slurry in relation to the composting process, and that the humic compound produced in the composting process and the slurry produced by the vermicompost process have higher P indices, organic and organic carbon, in relation to their corresponding, and the acidity index was practically the same for the slurries and humic compounds produced in both organic matter recycling processes.

Simulating the Operation of an Adaptive System for Controlling a Drying Process in an Organic Waste Recycling Device

This paper describes the synthesis of an adaptive automatic control system for the vortex dryer of a plant for recycling organic wastes. The application of an adaptive controller for loading the dryer with wet fuel is presented.

Recycling of Organic Wastes through the Vermicomposting Process of Cow Dung and Crop Residues

Fertilizer is considered to be one of the main inputs for increasing crop yields. Chemical fertilizer industries are highly energy intensive and have a fundamental dependence on natural gas supply. On the other hand, organic fertilizers are the safer sources of plant nutrients without any detrimental effect on crops and soil. In the era of technological innovation, the farmers are interested to grow HYV rice and other diversified crops to support huge population of Bangladesh. So various harmful chemicals were used which degraded the health of the soil. Vermicompost is an excellent, nutrient-rich organic fertilizer and soil conditioner. It can bring back the fertility of the soil. Vermicomposting with earthworms has been recognized as a composting technique that transforms complex organic substances into stabilized, humus-like product. The application of vermicompost to the soil is considered as a good management practice in any agricultural production system because of the stimulation of soil microbial growth and activity and mineralization of plant nutrients and increased soil fertility and quality. This research focuses on producing nutrient-rich organic fertilizer by vermicomposting process from biomass. An experimental setup was carried out in Doulatpur, Kushtia targeting 10 tons output per month. Cow dung and crop residues were collected and followed vermicomposting method. Three cycles were maintained in the experiments i.e. 120 days per cycle-360 days in total and counted the vermi population for each consecutive cycle. The output fertilizer was analyzed in the laboratory and it was observed that the component ratios were suitable for agricultural lands. This fertilizer can also be used as a remedy for the barren lands. For the sustainable crop production and net improvement of soil productivity, vermicomposing is an excellent process to produce organic fertilizer from biomass.Journal of Bangladesh Academy of Sciences, Vol. 42, No. 1, 1-9, 2018