Clean Index Research Articles

Formation and characterization of leaf waste into organic compost.

In solid waste management, pollution-free disposal of leaf waste in urban areas is still not standardized and adopted. According to the World Bank report, 57% of wastes generated in South East Asia are consisted of food and green waste, which can be recycled into valuable bio-compost. The present study shows a method of leaf litter waste management by composting it using essential microbe (EM) method. Different parameters, such as pH, electrical conductivity, macronutrients, micronutrients, and potentially toxic elements (PTE) were measured at zero to 50 days of composting using appropriate methods. The microbial composting was shown to mature within 20 to 40 days, and its maturity could be evaluated by the attainment of stable pH (8), electrical conductivity (0.9 mS/cm), and C:N ratio ≥ 20. The analysis was also performed on other bio-composts viz. kitchen waste compost, vermicompost, cow dung manure, municipal organic waste compost, and neem cake compost. The fertility index (FI) was evaluated based on six parameters viz. total carbon, total nitrogen, N ratio, phosphorus, potassium, and sulphur contents. The PTE values were used to calculate their clean index (CI). The results showed that leaf waste compost has a higher fertility index (FI = 4.06) than other bio-composts, except the neem cake compost (FI = 4.44). The clean index of the leaf waste compost (CI = 4.38) was also higher than other bio-composts. This indicates that leaf waste compost is a valuable bio-resource with high nutritive value and low PTE contamination, with a favourable prospective to be used in organic farming.

Evaluation of sludge quality in Indian sewage treatment plants to develop quality control indices.

Dewatered sludges from twenty-two sewage treatment facilities were characterized to develop the quality control indices in India. This study used fertilizer index (FI) and clean index (CI) as a tool for categorizing sludge utilization into different classes (A, B, C and limited use classes LU-1, LU-2, LU-3) by their fertilizing potential, toxicity level, pathogen presence, and vector attraction reduction criteria. The findings revealed that total P (as P2O5), total N, and K (as K2O) in the sludge samples ranged from 0.9 to 5.7%, 1.2 to 3.8%, and 0.1 to 1.5%, respectively. Moreover, all sludges belong to Class C and lower category due to the presence of toxic metals and pathogens. The helminth eggs were found in the range of 25-1450 Numbers/4gTS in sludge samples. The highest number of helminth eggs of 1450/4g of TS was found in the fecal sludge. The specific oxygen uptake rate (SOUR) values in the sludge samples varied from 0.3 to 4.9, with a median value of 1.3 and an RSD of 86% is way too high. It indicates that the sludge samples need further treatment to be less attractive as a food source for vectors and rodents. However, sludge samples have fertilizing potential and FI values ranges from 4.1 to 4.9, and CI value ranges from 2.5 to 5.0. It indicates that compost is best in quality and has high-fertilizer potential and low heavy-metal content, which is suitable for high-value crops such as organic farming. Further sludge treatment using typical composting, aerobic or anaerobic digestion, and solar or thermal drying could bring the sludges into the Class A and B categories.

Study on the qualitative assessment of in-vessel food waste compost by indexing method

The consumption of different food-based goods produces a considerable amount of waste that needs to be conserved in an eco-friendly manner. A study was carried out on food waste compost made from the in-vessel compost process for use in agriculture and its marketability for its fertility and contamination potential. Food waste samples were collected from the canteen and hostels of GITAM University, Visakhapatnam (Andhra Pradesh), India and were transferred to a 125Kg in-vessel food waste composter (Molten Mind F125) and allowed to digest for 24 hrs followed by curing for seven days. After curing, the samples were characterized for nutrient content for fertility index (FI) and heavy metal contamination for clean index (CI). The compost quality index was derived from FI and CI to assess its suitability for agriculture. The pH of the food waste compost sample was reported as 8.4 and the C/N ratio was 28, which was higher than the standard ratio (15-20). The other physicochemical characteristics were analyzed using the standard methods and the concentration of metals was analyzed using Inductively Coupled Plasma Mass Spectrometry ( ICPMS). From the analysis, it was evident that heavy metal concentrations were well within the permissible limits. Further, the compost was characterized to know the fertility index (FI) and contamination index (CI) and its suitability to the soil. FI value was reported as more than 3.1 and CI value more than 4, which indicated that compost was best in quality, having high-value potential and low heavy-metal content, which will be suitable for high-value crops such as organic farming.

Physicochemical and fertility characteristics of microalgal soil ameliorants using harvested cyanobacterial microalgal sludge from a freshwater ecosystem, Republic of Korea

The recovery and reuse strategy of cyanobacterial microalgal sludge (CyanoMS) is a novel sustainable platform that can mitigate cyanobacterial harmful algal blooms (CyanoHABs) in the freshwater system. This study aimed to assess the nutritional feasibility of harvested CyanoMS for microalgal soil ameliorants (MSAs) as efficient biofertilizers by the composting process. Most MSAs exhibited stable nutrient levels during the sequential metabolic phases for the entire period. The qualitative value of all MSAs using CyanoMS as a biofertilizer was verified by the excellent Fertility Index (FI), Clean Index (CI), and plant growth values. Also, successfully matured MSAs provided long-term support for retarded release of nutrients along the microbial transitional pathway. However, suitable CyanoMS contents of 11.7–37.6% (w/w) in MSAs were critical for efficient microbial activation and substrate inhibition. Since these results were fundamentally based on microbial transition on the CyanoMS content, optimum weight content and composting period were required. Nevertheless, MSAs were commercially applicable to high value-added crops due to their high fertilization potential and recyclable value.

Industrial Composting of Commingled Municipal Solid Waste: A Case Study of Shiraz City, Iran

Composting is a preferable treatment option for putrescible waste disposal. In the small-scale composting, the control of the process is easy and high quality compost is usually produced while the conditions of industrial composting and small-scale composting are so different especially in developing country that municipal solid waste (MSW) is collected as commingled. Unfortunately, there is still a lack of information and experiences regarding the successful industrial composting from commingled municipal solid waste (CMSW). Therefore, this study was conducted on the compost production from CMSW in Shiraz City, Iran, with the composting capacity of 100 tonnes per day. The common process of windrow composting was modified for industrial composting in Shiraz City. The efficiency of the modified process was assessed using physical, chemical, and economic analyses. In addition, the maturity and stability of produced compost was evaluated using different indices such as fertilizing index (FI), clean index (CI), static respiration index (SRI), cumulative respiration index (CRI), and C-CO2 production index (C-CO2 Index). Finally, solutions and suggestions were presented to improve the system performance. Results showed that although the input putrescible waste to composting site has low homogeneity, produced compost in Shiraz City has a “good” quality. The produced compost with FI and CI of about 4.2 and 3.6, respectively, has high fertilizing potential and medium heavy metal content and can be sold without any restriction. Based on the economic analysis, poor marketing, strategies of bad marketing, lack of public awareness, and visible impurities, in spite of complying with the required standards, are the main reasons for the low sale price. The results of this study can be valuable for industrial composting in the cities where wastes are not separated at source.

Evaluate the Quality of Some Imported Composts in Erbil Governorate

     One of the main limitations concerning the use of compost as fertilizer materials is the uncertainty of nutrient availability to plants, especially Nitrogen (N) and Phosphorus (P), due to their presence in both organic and inorganic forms, which are not all immediately plant available. When a good quality compost is applied to an agricultural soil it could reconstitute soils and be an important fertilization backup. The present study was carried out to evaluate the quality of some imported composts in Erbil. The compost samples included 10 most common compost imported from different countries (Bulgari, Pakistan, Russia, Morocco, Egypt, Tabriz, Turkey, Poland, Malaysia, and Jordan) with five replications were bought in different local agrochemical market and shopping. Using a completely randomized design (CRD). The results revealed that the fertilizer index (FI) of imported compost was ranged from 4.42 to 4.92 while the clean index (CI) was ranged from 4.20 to 4.80, all composts have a fertilizer potential value >4. However, the clean index value of compost has medium-heavy metals content, the statistical analysis in the present study indicated that imported composts (Bulgari, Pakistan, Russia, Morocco, Egypt, Poland, Jordan) has a good quality, while (Tabriz, Turkey, Malaysia) are best and proper for agriculture land. In general, the mean concentrations of all heavy metals were lower than the permissible limit of Indian and German standards. However, the concentrations of Cd in Bulgaria, Pakistan, Morocco, Egypt, Tabriz, Poland, Jordan compost were higher than the permissible limit of Indian and Germany standards. In addition, the concentration of Ni in Bulgaria, Morocco, Turkey, Poland and Jordan higher than the Indian and Germany standards (Table 5 and 6).

Spectral characterization and quality assessment of organic compost for agricultural purposes

PurposeThe study presents the physico-chemical, heavy metal and spectral characterization of aerobic compost to assess the suitability of its use for different purposes generated from two different municipal solid waste dumpsites located in the cities of Solan and Mandi in Himachal Pradesh.MethodsThe spectral characteristics of the compost material were determined using Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD) technique. The heavy metal analysis of compost material was analyzed through atomic absorption spectroscopy (AAS). The study also focused on the determination of the qualitative nature of compost by utilizing an indexing method based on Fertilizer Control Order (FCO) Standards. The utility of the compost was characterized on the values of ‘Fertility Index’ and ‘Clean Index’.ResultsThe Fertility Index (FI) of compost for Solan and Mandi was observed 3.5 and 3.6, respectively, whereas Clean Index (CI) of compost for both regions was observed 4.0 and 5.0 at the 60th day of sampling, respectively, with the former being classified as category D and the second being classified as category A of high fertilizing potential.ConclusionsThe MSW compost of Solan cannot be used as fertilizer due to its low fertilizing potential. The heavy metal concentration for the study regions has been found within the permissible limits of the fertility control order standards. It is concluded from the study that aerobic composting is a suitable option for processing of waste as well as it can reduce the weight of organic waste in the dumpsite.

GOODS-Herschel: identification of the individual galaxies responsible for the 80–290μm cosmic infrared background

We propose a new method of pushing $Herschel$ to its faintest detection limits using universal trends in the redshift evolution of the far infrared over 24$\mu$m colours in the well-sampled GOODS-North field. An extension to other fields with less multi-wavelength information is presented. This method is applied here to raise the contribution of individually detected $Herschel$ sources to the cosmic infrared background (CIRB) by a factor 5 close to its peak at 250$\mu$m and more than 3 in the 350$\mu$m and 500$\mu$m bands. We produce realistic mock $Herschel$ images of the deep PACS and SPIRE images of the GOODS-North field from the GOODS-$Herschel$ Key Program and use them to quantify the confusion noise at the position of individual sources, i.e., estimate a "local confusion noise". Two methods are used to identify sources with reliable photometric accuracy extracted using 24$\mu$m prior positions. The clean index (CI), previously defined but validated here with simulations, which measures the presence of bright 24$\mu$m neighbours and the photometric accuracy index (PAI) directly extracted from the mock $Herschel$ images. After correction for completeness, thanks to our mock $Herschel$ images, individually detected sources make up as much as 54% and 60% of the CIRB in the PACS bands down to 1.1 mJy at 100$\mu$m and 2.2 mJy at 160$\mu$m and 55, 33, and 13% of the CIRB in the SPIRE bands down to 2.5, 5, and 9 mJy at 250$\mu$m, 350$\mu$m, and 500$\mu$m, respectively. The latter depths improve the detection limits of $Herschel$ by factors of 5 at 250$\mu$m, and 3 at 350$\mu$m and 500$\mu$m as compared to the standard confusion limit. Interestingly, the dominant contributors to the CIRB in all $Herschel$ bands appear to be distant siblings of the Milky Way ($z$$\sim$0.96 for $\lambda$$<$300$\mu$m) with a stellar mass of $M_{\star}$$\sim$9$\times$10$^{10}$M$_{\odot}$.

Qualitative assessment of municipal solid waste compost by indexing method

Background A study was carried out to classify municipal solid waste (MSW) compost produced in Delhi, India for their marketability and use in different area with respect to physico-chemical properties, fertilizing and heavy metal polluting potentials. Results The pH of the compost was slightly alkaline (8.4 ± 0.02) and C:N ratio (9.46 ± 0.91) was low as compared to Fertilizer Control Order (FCO) Standard, Government of India, 1985. Sample analysis was carried out using standard methods. The concentrations of some selected heavy metals, e.g., Zn, Cd and Ni were within the permissible limit of FCO standard. However, the concentrations of Cu, Pb and Cr exceeded (66.7 %) the permissible limit of FCO standard. Further, the compost was characterized to know the fertilizing potential and its potential to contaminate the soil. Fertilizing index (FI) was calculated from the values of TOC, TN, TP, TK and C:N ratio and clean index (CI) was also calculated using heavy metal concentrations. FI value of compost was varied from 4.47 to 4.60, whereas CI value of compost was varied from 2.33 to 2.87, respectively. Conclusions The study results indicated that majority of MSW compost produced in Delhi failed to achieve quality control guidelines of FCO standard. The compost has fertilizing potential, however, certain risk to the environment. Hence, the prepared compost in Delhi was not suitable for its intended purpose. Post-treatment of compost is required to improve the quality of compost, which can be utilized for agricultural purposes.

Quantitative and physico-chemical characterization of domestic solid waste in a typical Nigerian municipality

In the present study solid waste were collected from households, banks, restaurants, higher institution, open dump and a final disposal site of Nigerian municipality with a view to determining waste generation rate, relative waste compositions and its physicochemical properties. During the course of study average rate of solid waste generation was found to be 0.39Kg/capita/day. A highly negative correlation (R2 = 0.99) was observed between per capita waste generation and household size (n) for n ? 4. The waste collected from households consisted of putriscibles (47%) 11% water proof, 6% plastics, 4% glass, 3% clothes/textiles, 2% diapers and 19% of other unclassified materials. Due to the activities of scavengers, the relative proportion of recyclables such as plastic, glass and metals decreased as waste materials transited from households to the final dumpsite via open dumps, while the other fractions increased. It was found that 79% of the solid waste generated can either be recycled (32%) or composted (47%) however; only 12% is recovered for recycling/reuse while composting is hardly practiced. The three most important factors responsible for relative differences in the composition of solid waste obtained from different sources are scavenging, biodegradation and leaching. The putriscible fractions from households, curb sides and the final disposal site were assessed for their suitability for composting using the clean index (CI) criteria. It was found that the final disposal site with a CI of 3.3 on a scale of 5 was a better source of compost material than freshly generated household waste (CI = 2.9) and curb side waste (CI = 2.4).