جستجوی مقالات مرتبط با کلیدواژه « Waste management » در نشریات گروه « اکولوژی »

Vegetable waste (VW) could cause environmental problems if not properly managed. Due to rural living conditions and a relatively low residence density, VW is usually disposed of in landfills. Waste management should be engineered in a way to process the waste into value-added products in a sustainable manner. This review evaluates four bioprocessing techniques for this

anaerobic digestion (AD), vermicomposting (VC), black soldier fly composting (BSFC), and composting.

A systematic search involved databases from Scopus using keywords like “vegetable waste; anaerobic digestion; composting; vermicomposting; black soldier fly”. By reviewing and synthesizing 173 articles (with 162 from 2019–2023), this paper summarizes and illustrates the information collected.

In a systematic search, AD and composting easily surpassed 2000 publications (from 2013 to January 2023). Besides composting emerged as a cost-effective (for MYR 1.40/kg) bio-processing technique in terms of production cost. This review on VW composting is based on an acceptable C/N ratio (30–50), moisture content (50%–80%), ratio of VW to additives (typically 30:70), efficient additives, and inoculation strategy. This review also summarizes the maturity index and illustrates the usage of compost and leachate as fertilizer.

VW composting in rural areas is reliable and beneficial because it uses a small-scale reactor and has the potential for a circular economy in the community.

Composting is known since long for reducing the use of synthetic chemical fertilizers. These fertilizers are applied to the crops for the supply of required macro/micronutrients. The present study describes how to decompose biodegradable solid wastes quickly into compost without harming the environment.

The microbial inoculums were developed from cow dung concentrate. The cow dung concentrate was mixed with water. The cow dung concentrates, and water mixture was then mixed with another water solution containing Jiggery. After a week, a creamy layer was observed to have formed. This confirms the development of microbial inoculum.

After 2-3 days, temperature started to increase slowly. On the 15th day, temperature of the compost pile was 40 °C. At this temperature, the waste changed its colour and showed rapid decomposition. On the 25th day, temperature was noted to be around 60 °C. This showed the completion of the process. After 30 days, the compost was ready and showed signs of the process of maturation. Decrease in temperature confirmed completion of maturation process and complete conversion into compost.

The cow dung microbial inoculum consists of decomposing bacteria, protozoa and fungi which are effective to convert biodegradable waste into bio-fertilizer. The regular application of synthetic fertilizers causes adverse effect on greenhouse, environmental pollution, killing of earthworms and other beneficial micro-organisms of the soil, marine inhabitants, depletion of ozone layer, increase of toxicity among human beings due to excessive heavy metals, spoilage of soil fertility, and change in the soil pH.

Waste and waste disposal is a universal problem and attention is required in all ways. The plant generated waste (leaf litter) is also a type of organic waste that creates multiple issues in urban areas. Vermicomposting is a suitable alternative safe, hygienic, and cost-effective disposal of organic solid waste with the help of earthworms. The present study focussed on the conversion of leaf litter of Lagerstroemia speciosa trees from the local places to beneficial vermicompost. Vermicompost was prepared using leaf litter (LL) supplemented with cattle dung (CD), food waste, and earthworms. The study also explored the physical factors like temperature, pH, moisture, and biomass reduction of the vermicompost (100% & 50% LL) and CD. An alkaline pH (8.97±0.04), nominal temperature (22.63±0.26°C) and high moisture content (72±2.75%), as well as increased biomass reduction (7.45±0.69 cm) was observed at the end of the vermicompost process. The study also performed plant growth analysis using vermicompost as manure. Increased growth, germination, and pest resistance were observed in the plants in which compost was utilized. The current study paves the way to create a green environment by reducing and converting leaf litter into vermicompost which will act as a circular economy.

Tourism industry growth in many regions of the world, along with the positive and negative economic and social consequences, has environmental impacts leading to irreversible damage. The present study aimed to investigate the impact of the tourism industry on municipal solid waste amounts especially plastics in Nowshahr City, Northern Iran. The physical components of solid waste were determined based on a simple random sampling method. The samples were collected during a one-year study period (from spring 2015 to winter 2016). The Kolmogorov-Smirnov test was performed to determine the normality of data distribution. Also, the One-Way ANOVA and Tukey tests were implemented to investigate significant differences between the seasons. The Delphi-AHP method was used to find the main criteria of solid waste increasing or the tourism effects reducing. The result showed that plastic (15.98%) and polyethylene terephthalate (PET) bottles (11.42%) constituted the highest physical components of solid wastes in the study period. The highest amounts of PET and plastic wastes were observed in the summer, exhibiting significant difference than in the winter (p < 0.05). The results showed that amount of waste in Nowshahr is completely influenced by the number of tourists, irregular presence of tourists throughout the year and season. Also, the lack of environmental awareness in the region has led to the accumulation of significant amounts of recyclable waste such as plastic. The result indicated that the importance of knowledge about the amount of produced wastes in managing and reducing environmental effects in tourism areas. Therefore, special attention should be paid to the public education and culture regarding to the separation of wstes from the source and also recycling the solid wastes as well as the public participation in study area.

Purpose The composting of manure is the common practice for the feedlots of cattle, but emission of gasses during composting was poorly understood. So, there is need to enhance nutrient contents in composting material, reduce odor and other impurities by various amendment in composting material. This study was planned to find best composting condition for quality compost production. Method Experiment was performed under completely randomized design (CRD) with three factors. First factor (treatment) comprised of three levels e.g.: T1: CM + WS (25% + 75%), T2: CM+WS (50%+50%) and T3: CM +WS (75% +25%). Second factor was composting conditions consisted of two levels e.g., aerobic and anaerobic conditions. Third factor was duration of composting (days). Results Composting conditions significantly influenced emission of greenhouse gasses and compost quality. Maximum gas volume (658 ml) and methane production (58.89%) were produced under anaerobic decomposition of cow manure and wheat straw 3:1, respectively. Maximum carbon dioxide (18.56%) was produced under the aerobic decomposition of cow manure and wheat straw mixed in 1:3 ratio. Nutrient analysis of compost revealed that high-quality compost with maximum total organic carbon (20.1%), total nitrogen (2.47%), phosphorus (0.76%) and potassium (1.49%) was observed from compost produced from anaerobic decomposition of cow manure and wheat straw mixture  @ 3:1.Conclusion This work highlights that the anaerobic composting of cow manure and wheat straw has potential to produce the biogas as well as best quality compost.

Purpose :

The study was conducted to develop and assess the feasibility of the low-cost mechanical interface as an alternative to the conventional land-based bin type vermicomposting process. The idea was to reduce the drudgery, enrich the nutrient status and reduce the cost of preparation of vermicompost.   

Method:

 A smart vermicomposting bin comprising of Arduino, feeding hopper, shredding rollers, spiral mixing unit, degradation bin and harvesting gate was fabricated for the preparation of vermicompost from Dal Lake aquatic weed in Kashmir valley. Eisenia fetida earthworm facilitated the degradation process.

Results:

  The Dal lake aquatic weed was degraded in the smart vermicomposting bin. The turning frequency was set as 10 days and 20 days. The performance parameters at 10 days turning interval were pH 7.05, electrical conductivity 0.837 dSm-1, available nitrogen 1.15%, available phosphorus 0.06%, available potassium 1.91%, organic carbon 26.2% and C:N ratio 16.3:1 after 60 days degradation period. The comparative evaluation revealed that increase in available nitrogen, phosphorus and potassium at 10 days turning interval was higher by 4.01%, 6.06%, 4.94% than 20 days turning interval. The benefit – cost ratio was 0.45 in first year and 1.78 in second year with a pay-back period of 19 months. The unit cost of vermicompost production was Rs. 13 per kilogram.  

Conclusion:

 The involvement of mechanical intervention in vermicomposting can help in reducing the dependence on scarce land and addressing the issue of peak labour shortage. Moreover, the automation of the system can reduce the human errors.

Purpose :

Our study concerned the recovery and reuse of sludge from aquaculture system implemented in Ain Defla District situated in the North-West of Algeria. As a biotreatment and ecological stabilization technique, vermicomposting of aquacultural sludge with Eisenia fetida earthworms has been advocated. The main goals were to assessthe impact of vermicomposting on the quality of aquacultural sludge in terms of stabilization and hygienization, and to investigate its potential use in agriculture as a biofertilizer without compromising the quality of agricultural products.

Method :

The vermicompost was used to amend the soil and assess its impact on some growth parameters of Phaseolus vulgaris.L snap bean was considered. The physical and chemical parameters of sludge were also evaluated.

Results:

 Significant increase of earthworms’weight and length by more than 27 and 22%, respectively, after 21 days of sludge vermicomposting was obtained. Also, significant differences were noted for selected plants’ agronomic parameters in soils amended with aquacultural sludge, compared to the control (unamended soil). In fact, beans with vermicomposted sludge had substantial increases in plant height, leaves weight, and chlorophyll (a) level of 29 cm, 3.6 g, and 0.8 g/g, respectively, compared to 20 cm, 1.5 g, and 0.46 g/g in control.The results also showed that the vermicomposting process allowed for decreased faecal coliforms and streptococcus in the aquacultural sludge.

Conclusion:

 The end-product was a safe biofertilizer for use in agriculture.

Purpose Crude oil pollution adversely affects the environment and its remediation presents significant challenge due to its complex nature. Bioremediation approaches have proved effective and the use of organic wastes makes the process eco-friendly. Therefore, this study investigated the effects of organic manures amendments of crude oil polluted soil on the growth and performance of maize (Zea mays L.) under potted environment at the botanic garden of University of Port-Harcourt, Nigeria.Method The loamy soils in different pots (5.0 kg each) were polluted with crude oil in six factorial treatments set (0.0%, 2.0%, 4.0%, 6.0%, 8.0% and 10.0%) and allowed for two weeks. Thereafter, the polluted soils were subjected to different organic manure amendment: poultry-manure, cow-dung, saw-dust, combined poultry-manure + cow-dung, combined poultry-manure + saw-dust and combined cow-dung + saw-dust manures with two sets of control: polluted soil + no organic manure and non-polluted soil + no organic manure. The amended soils were allowed for two weeks before sowing viable maize seeds and the seedling monitored every two weeks after germination for a period of eight weeks.Results Crude oil pollution impaired the maize seed germination, growth and development. Organic manures amendments of polluted-soil significantly improved (P < 0.05) maize plant agronomic characteristics with combined manures especially poultry-manure + cow-dung showing highest improvement than other combined or single manure treatment.Conclusion Combined organic manures amendments of crude oil polluted soil especially cow-dung + saw-dust were found to be environmentally friendly and beneficial for maize crop production.

PurposeThe management of household wastes has been a real challenge for the capital city of Cameroon for some years now. In order to adopt ecological and sustainable strategies for better management of organic fraction of solid wastes, the present work was aimed to propose a sustainable alternative for the recycling of household organic waste through a vermicomposting process. Method A vermicomposting of household organic waste was carried out during 46 days, preceded by 23 days of pre-composting. Then, three treatments were established by mixing epigeic earthworms with different proportion of pre-composted waste. Maturation parameters such as pH, electrical conductivity (EC), C/N ratio, ammonium (N-NH4+) and total organic matter (TOM) were monitored about four weeks. The agronomic quality of the vermicompost was also determined at the end. Results During pre-composting, the temperature reached a maximum of 54.3±5.4°C suitable for the elimination of potential pathogen. The pH varied between 9.44 and 8.53 leading towards neutrality at the end of the vermicomposting process. The obtained mean values of C/N ratio and the TOM were respectively 11.04-11.68 and 25.82-27.19% in line with the AFNOR (NFU 44-051) guideline. The obtained vermicompost revealed high levels of nutrients such as N, P, K, Ca and Mg. The phytotoxicity test on lettuce showed germination rates above 50%, revealing the non-toxic nature of the vermicompost produced. Conclusion The vermicompost were rich in nutrients and exhibited the non-phytotoxicity. Thus, vermicomposting can be applied in the context of Cameroon to transform organic waste into organic fertiliser suitable for sustainable agriculture.

This paper presents an overview of the current municipal solid waste (MSW) management in Rasht City, Guilan Province, Iran, followed by evaluating the potential for waste-to-energy. The data of different MSW functional elements were collected from previous works, available reports, interviews and meetings with specialists in the field. About 800 tons MSWs are generated in Rasht per day, of those, over 75% are organic wastes followed by paper and cardboard comprising 5.9%. The daily theoretical energy contained in the city MSWs was estimated to be over 591.62 megawatt hour (MWh, over 215942.54 MWh per year). Almost 500 tons of daily MSWs are directly transferred to Saravan as the biggest landfill in north of Iran with an area of about 30 ha, while the remaining portion is treated in the Guilan composting plant. Landfill mining calculations showed that we could recycle about 3008947, 36793, 61443 and 18366  tons of plastics, textile, wood and  rubbers collected from Saravan landfill respectively. A simple assessment of waste-to-energy potentials from organic wastes using operational conversion coefficients revealed that by employing the combination of waste-to-energy and gas turbine technology, an estimated energy of 227.668 MWh can be produced from the Rasht daily food wastes. Although MSW management in Rasht  has been improved over the last decade owing to the establishment of waste recycling and composting organization, however it is still far from the standard situation due to lack of comprehensive waste management planning, financial resources and infrastructures

A pilot composting project was initiated as part of a 200 tons/day solid waste recycling plant with active involvement of several local stakeholders. The project aimed at introducing compost production and use in the village of Al Jalameh, Palestine. This paper describes the successes and lessons from the pilot project. Based on the data collected on the population, waste production and economic activities, the best production methodology and composting units were designed and piloted. The compost was produced from animal manure, farm waste and organic fraction of domestic solid waste. Approaches to increase profit and sustain the initiative was implemented. The facility managed by Al Jalameh Agricultural Cooperative Society, recycles 60% organic fraction of domestic waste reducing the quantity of waste to the landfill. An estimated 1425 m3/year of compost are required for local agriculture while 800 tons/year is produced. With most of their compost coming from Israeli sources, the composting facility is at a competitive advantage. To increase the profit, around 28,125 kg of waste plastic sheets from greenhouses are collected for recycling each year generating a stable income of 5625.00 JOD/year. The compost produced in the village is purchased by the local farmers increasing access to compost at competitive price. Farmers are economically encouraged by compost production that could solve the organic waste management issue and at the same time guarantee a sort of “self-production” of fertiliser useful for local agriculture. This initiative could be extended to other villages in Jenin and other developing countries where agriculture is their major occupation.

The consecutive amendment of composted tannery sludge (CTS) could promote changes in the status of soil microorganisms. Thus, this study evaluated the changes on microbial C and enzyme activities in soil after 9 years of CTS amendment.

CTS was amended from 2009 to 2018 at five rates: 0, 2.5, 5, 10, and 20 ton ha−1. In 2018, the soil chemical properties (pH, electric conductivity, P, K, Cr, and total organic C), microbial C and enzyme activities were evaluated after 30 days from the amendment.

The values of chemical properties increased after nine years of CTS application. The content of microbial C and the enzyme activities increased with the amendment of 2.5 and 5 ton ha−1, and decreased with the amendment of 10 and 20 ton ha−1.

This study showed that the amendment of 10 and 20 ton ha−1 of CTS increased soil pH and Cr concentration and promoted a decreasing on soil microbial C and enzyme activities.

Four different types of composts were assessed in two methods of application for their potential to support organic tomato yield. A 2-year experiment was conducted using four different soil conditioners: cow manure (CM), household compost (HC), spent mushroom compost (SMC), and vermicompost (VC). Three different application rates (10, 20, and 30 t ha−1 for all composts except VC and 3, 6, and 9 t ha−1 for VC) were included as a second factor. Two methods of fertilizer placement (as a row behind the root area and broadcast on the field) were considered as a third factor. The yield was influenced by different soil conditioners and placement method in the first year; in the second year, just interactions were significantly different. Treatments with CM showed significantly higher tomato yield in the first year (103 t ha−1) compared to other composts, but in the second year, SMC produced a higher yield (58 t ha−1). The experiment indicated that the treatment with CM in high level with broadcast application had higher dry matter (DM) production (3.1 t ha−1) in 2014, and treatment with CM in low rate and broadcast application had higher DM production (5.8 t ha−1) in 2015. Compost broadcast on the plots showed a higher yield production in case of similar rates and compost type. The proper rate of compost application is dependent on the method of compost placement.

In this study, vermicomposted tannery wastes were applied in the organic cultivation of sweet pepper in a greenhouse. The effects of this organic matter addition on plant development and on the distributions of Cr(III) and Cr(VI) in plant tissues and organs were assessed. In a greenhouse, organic sweet peppers were cultivated adding vermicomposted tannery to the substrate (sample VRC) and the results were compared with the samples control (dYL; only soil) and reference (NPK; adding mineral fertilizer). The growth, nutritive value and fruit production were assessed to evaluate the plant development in different types of substrate. Besides evaluating the biostimulant effect of vermicomposts, the distributions of Cr in plant tissues were also studied. Up to three harvested sweet peppers were obtained per plant, compared with only one fruit for the reference treatment with NPK addition. Based on the Cr dynamics in the plants, the highest concentration was found in the fruits, varied as follows: fruits > stem and stalks > leaves = root; however, the Cr concentration in the fruits was statistically the same across all treatments. Additionally, only Cr(III) was detected and quantified in the fruits. The addition of vermicompost was biostimulating to plants and positively influenced their development. Based on the Cr dynamics in the plants, since the Cr concentration was the same across all treatments, it demonstrated that the addition of tannery residues to the vermicompost did not negatively influence the health benefits or food security of the produced fruits.

Poultry industries produce a lot of feathers which are considered as waste and needs to be managed properly. Poultry feathers are rich with keratin protein and therefore they could be a source for good nitrogen fertilizer. Proper treatment of poultry feather waste (PFW) might be an environmental friendly solid waste management tool and a good source of N-rich organic fertilizer. PFW was treated under a mixture of both aerobic and anaerobic processes. Treated poultry feather waste (TPFW) was analyzed for different nutrient elements. TPFW was applied to the soil at 4, 8, 12 and 16 t/ha along with control. Ipomoea aquatica was grown as the test plant to evaluate the growth performance under different rates of TPFW application. Plants were harvested 7 weeks after seed germination. TPFW contained higher amount of organic matter (35.9%) and total nitrogen (4%). Other major nutrient elements were found to be satisfactory. Color of the plants were observed greener in TPFW applied plants than control plants and the green color was pronounced with increasing rate of TPFW application. Plant height (cm/plant), leaf number per plant and weight of plants (g/plant) was also increased significantly due to the application of TPFW at 12 t/ha and above. Proper treatment of PFW might be an environmental friendly, cost effective and sustainable strategy for PFW management that will also play a vital role in nutrient (especially nitrogen) recycling to the soil.

The study evaluates and provides an overview of the nutritional importance of 19 selected food wastes as aids in human/livestock/soil/plant health.
Nitric acid-digested extracts of food wastes belonging to four different classes (fruits, vegetables, oilseeds and beverages) were analysed for different elements in an inductively coupled plasma mass spectrometer.
Our study recommends spent coffee grounds, tea leaves, radish peel, watermelon rind and pineapple skin that contain substantially high concentrations of essential elements such as N, P, K, S and Fe for their use as: (a) substrates for composting, (b) biofertilizers, (c) soil amendments, and (d) bioadsorbents of toxins. Although these food wastes are rich in essential nutrients, we do not suggest them for the preparation of food supplements as they contain non-essential elements in concentrations beyond the human safety limits. However, food wastes like banana peel, plum pomace and pistachio shell that contain low and permissible concentrations of toxic elements can be recommended as dietary supplements for oral intake in spite of their lesser essential elemental composition than the other residues examined.
Our study confirms that food wastes are rich sources of essential nutrients and there is need to harness their real industrial systems.

The aim of this research was to evaluate the suitability of pineapple waste for production of decomposable nursery pots.
The experiment was completely randomized, with three replicates and eighteen formula treatments. Treatments consisted of varying ratios of pineapple waste to binder, including 2:1, 1:0 (fresh pineapple waste), 1:1, 1:1.5, and 1:2; the textures tested were coarse, medium, and fine, and the pot thicknesses were 0.5, 1.0 and 1.5 cm.
The results revealed that the physical and chemical properties of pineapple waste were suitable for use in nursery pots on an experimental scale. The optimal physical and chemical properties for a decomposable pot included a 1:0 ratio of pineapple waste to binder, a coarse structure, and a pot thickness of 1 cm. With these properties, the pot degraded in more than 45 days, N and P release rates were 0.49% and 7.97 mg-P/kg, respectively, and the average absorption rate was 258.43%. Saturation occurred in 45 min, and the water evaporated in 444 h.
In terms of cost production per pot, fresh pineapple waste cost 0.0075 USD for a three-and-a-half inch diameter decomposable pot (excluding logistical costs). Therefore, this study provides a possible method for waste management.

Chicken processing results in the production of a lot of blood which if disposed on land poses environmental hazards in terms of land pollution. The aim of the study was to develop an aerobic composting process for chicken blood to produce a nitrogen-rich soil amendment for use in agriculture. The study involved composting of blood and maize stover of different proportions (10%, 30%, 70% and 100% maize stover) in compost bins over 72 days and determining which proportions would yield compost with greater potential to support plant growth.

The performance of the different compost mixtures was evaluated by monitoring internal temperature, mineral N (NH4 + -N and NO3 − -N), C/N ratio, pH, electrical conductivity and total cations. The concentration of ammonium N decreased by 8.75%, 50.5%, 33.5% and 18.8% for the 10%, 30%, 70% and 100% stover treatments, respectively, with composting time. Nitrate N peaked to 1.93 and 1.06 mg/kg for the 30% and 70% treatments, respectively, on day 43, while it peaked to 1.54 and 0.54 mg/kg for the 10% and 100% treatments, respectively, on day 50. The C/N ratios decreased significantly (p < 0.001) for all treatments.

The 10% and 30% treatments had better composting performance than the 70% and 100% treatments as they reached and maintained thermophilic temperatures for at least 8 days. The 10% and 30% treatments appeared to have the greater potential of supporting crop growth.