Iranian Journal of

Background and Objective: Today, workshop industries play an important role in urban development by creating effective employment in urban areas. It has been stated that these small industries can cause environmental pollution. The purpose of this study was to investigate and analyze the contaminations caused by the workshops in Qom in 2016.
Materials and Methods: The present study was descriptive-analytic-cross sectional. First, all of the city's businesses were listed in 67 relevant :::::::union:::::::s. After identifying the polluting businesses, a total of 223 classes of all :::::::union:::::::s were randomly screened. Sewage, solid waste, air, sound, soil and landscape pollution were investigated. According to 15 specialists and using Expert Selection software, each pollution type and rating of each class were weighed and determined.
Results: The results showed that the wastewater, solid waste, air, noise, and landscape pollution with a score of 0.399, 0.259, 0.169, 0.097, and 0.027, respectively, are important.  Accordingly, in terms of the total contamination of the studied occupational units, authorized dealers of car sales, carwash, guest house, carpet cleaning, bath, brick plants, chalk plants, gemstones, chelokbaby, mosaic making, lathes and blacksmans, iron doors and window making, general blinds and shuttering, ceramic making, wood processing industry, mechanical, polishing with a total score of 1, 0.889, 0.881, 0.872, 0.709, 0.644, 0.644, 0.641, 0.62, 0.609, 0.582, 0.569, 0.552, 0.546, 0.518, 0.499, and 0.499 had unfavorable status, respectively.
Conclusion: In order to reduce the environmental pollution caused by these businesses, continuous monitoring and inspections should be carried out in the short term. Moreover, the polluting industries should be relocated out of the city in the long term.
 

Background and Objective: The aim of this study was to assess the sensitivity and uncertainty analysis of a mass balance model to estimate the rate of aerobic processes in a landfill.
Materials and Methods: Monte Carlo simulation is a common method to evaluate uncertainty of the results of a model. Here, we used a Monte Carlo (MC) simulation. The data obtained from the experiments were used as a baseline. Considering a uniform Probability Distribution Function (PDF) within ±15% deviation, samples were taken from the baseline data. Using randomly selected inputs, model was executed for 1000 iterations and outputs were evaluated. Then, the total Sobol index for each input parameter was determined. The uncertainty of each output was presented by standard error and means observed in MC simulation. 

Results: The results of this study revealed that while the uncertainty for the rate of composting process was mainly originated from the measured value of CO₂ flux, the evaluated value for the rate of anaerobic digestion process was highly influenced by the value measured for CH₄ emission flux. All inputs contributed equally to the uncertainty in the evaluated values for the rate of methane oxidation process. Although a variability of 15% was assumed for the model inputs, the mean value for the outputs from Monto Carlo simulations were close to those obtained by using base values that were in most cases within ±10% limit.

Conclusion: The majority of the uncertainty in the outputs came from the variability in the measurement of the flux of CH₄ and CO₂. The error in these parameters, however, can be minimized by increasing frequency and replicates of gas samples as these parameters are measured directly for each location.

Background and Objective: Concentration prediction with Gaussian dispersion models is highly sensitive to meteorological data. The lack of sounding data station in developing countries may lead to large error and uncertainty in air pollution modeling results. In this paper, the effects of estimated upper air data on the model output concentration values were investigated.

Materials and Methods: AERMOD model was executed once with real upper air data and also with estimated upper air data separately. T-Student and LEVENE tests were used to evaluate the significant differences between concentrations in two modes of using actual and estimated upper air data.

Results: The results showed that large differences in concentration between the two methods. In long term modeling, there was up to 33% differences between real and estimated upper meteorological data and up to 63% differences for short term modeling. A large difference was also observed between boundary layer parameterization values in each case. The statistical analysis showed a meaningful difference (p=0.00) between the cases. The differences between Z_ICNV, DT/DZ, W* were 7.1%, 48%, and 19%, respectively.
Conclusion: The use of estimated upper meteorological data in comparison with measured data may lead to a large error. The AERMOD modeling results with estimated meteorological data must be expressed with appropriate uncertainties and confidence interval.
 

Background and Objective: Treatment of hospital wastewaters has an important role in reducing the discharge of organics and pharmaceutical compounds into aquatic environments. Nowadays, advanced oxidation processes were extensively used for the removal of organic compounds from treated effluents. The study aimed to examine organic compounds removal from real treated effluent of a hospital treatment plant using a lab scale UV/H₂O₂/TiO₂ process by optimizing the process.
Materials and Methods: The effluent characteristics including COD, TOC and DOC were measured and recorded. A hybrid advanced oxidation process (UV/H₂O₂/TiO₂) was used for the removal of organic compounds. The experiments were designed using surface response methodology (RSM). The effects of the independent factors including pH, duration of UV irradiation, H₂O₂ and TiO₂ concentrations on COD, TOC, DOC and the approximate cost of treatment were assessed by analysis of variance (ANOVA).
Results: The optimal condition was 7.2 for pH, 50 mg/L for H₂O₂, 100 mg/L for TiO₂ and 19.65 min for irradiation time. This condition provided the maximum removal percentage for organic compounds with a minimum cost. The removal efficiency for TOC, DOC and COD were 63.9, 52.9, and 64.7%, respectively. The treatment cost was approximated to be $ 0.71 per one liter of the effluent.
Conclusion: Irradiation and H₂O₂ concentration had the greatest impact on the cost of the treatment. UV/H₂O₂/TiO₂ process seems to be an expensive process for tertiary treatment of wastewater. However, further investigations are required to evaluate the cost effectiveness of the process for a full scale operation.
 
 

Background and Objective: Hydrocarbon processing industries are considered as potential sources of volatile organic compounds (VOCs) due to their specific nature. These compounds can directly or indirectly through producing secondary pollutants have adverse effects on the health of individuals. Therefore, identification of them is an important step in the formulation of control programs. This study aimed to identify the type and amount of the most important volatile organic compounds in the South Pars region.
Materials and Methods: In this study, industrial processes located in the region were investigated and information was gathered for estimation of VOCs emissions. The emission was estimated over a one-year period and was ranked according to three criteria including emission, health hazards and ozone production potential.
Results: The results showed that the greatest emission was due to equipment leakage and storage tanks (64%), cooling towers (21%) and flaring (11%). The 171 VOCs were determined in Plum of these processes and propylene had the greatest contribution (21%). The alkenes had the highest share in total mass (41%) and ozone production (78%). By weighting the list based on the three criteria mentioned above, formaldehyde is the most important emitted VOC and the main sources of it were olefins and aromatic units.
Conclusion: This method can be a useful tool for identifying effective organic compounds in such areas. Here, the optimum control strategy is mitigating of emission of formaldehyde from the aromatic and olefins processes. The next priority is to control propylene, ethylene and butylene emission sources.
 

Background and Objective: The purpose of this cross-sectional study is to evaluate the microbial contamination of food-handlers' hands and food contact surfaces in food preparation and distribution centers.
Materials and Methods: This study was performed in 2019 in Fardis city of Alborz province. In this study, 100 samples of food contact surfaces and 48 samples of staff hands were collected from three traditional bakery units, pastry centers and snack shops and the microbial load was determined using a luminometer device. The samples were then analyzed for the presence of coliforms, Escherichia coli and Staphylococcus aureus bacteria.
Results: Among the samples studied, 62 samples (62%) of contact surfaces and 27 samples (56.25%) of food-handlers' hands had microbial load more than 30 RLU.  According to the results, the main cause of microbial contamination of equipments were 44.40% of Coliform bacteria and 11.10% of Staphylococcus aureus on the equipment of confectionery centers,  10% of Escherichia coli, 20% of coliforms and 20% of Staphylococcus aureus were detected on food tools and 2.30% of Escherichia coli, 14% of coliforms and 14% of Staphylococcus aureus –on the tools of traditional bakeries.Moreover coliform bacteria was noticed onconfectionary-handlers' hands and all three types of bacteria were also found on the hands of bakers.
Conclusion: The results showed that the cleanliness of food contact surfaces and the personnel hands hygiene was in poor condition which may pose serious threat to public health. Therefore, adequate personal hygiene practices, food safety and inspections should be implemented to protect the health of society.

Background and Objective: Improper landfilling of drilling waste has adverse effects on the environment and human health. This study aims to select suitable landfills for oil and gas drilling waste on Qeshm Island using GIS and AHP.
Materials and Methods: In this study, a weighted map was prepared based on each criterion affecting the site location. In the next step, each of the prepared layers was ranked. Higher rating indicated the importance of each layer while lower values corresponded to their insignificane.
Results: The reasults of this study showed that the distance from population centers (weight 0.222), communication network (roads) (weight 0.169) and surface waters (weight 0.142) are important parameters for landfill siting. The combination of ranked maps and the weights obtained from AHP, divided the landfill area to “completely suitable”, “suitable”, “relatively suitable”, “relatively unsuitable” and “unsuitable”.
Conclusion: Priorities identified in “completely suitable” areas can be the basis for decision-making, and appropriate locations can be on the agenda as next priorities.

Background and Objective: Antibiotics are hardly decomposable and resistant contaminants in the environment that according to their anti-biological properties, it is necessary to eliminate or reduce the amount of them before entering the environment. Therefore, the main goal of this research is to investigate the Fenton and Fenton-like process efficiency for the treatment of wastewater containing Spiramycin antibiotic.
Materials and Methods: The effect of independent variables including pH, contact time, oxidant concentration (H₂O₂), and catalyst concentration (Fe²⁺ and Fe³⁺) on the COD removal efficiency were measured using COD meter. The ranges and number of experiments were assigned by RSM (Response surface method) using design expert software.
Results: The optimum conditions of Fenton process with treatment efficiency of 63.31% were obtained at pH 4, hydrogen peroxide concentration of 50 mg/L, Fe²⁺ concentration of 75 mg/L and contact time of 5 min. The optimum conditions of Fenton-like process with treatment efficiency of 51.21% were obtained at pH 3, hydrogen peroxide concentration of 60 mg/L, Fe³⁺ concentration of 137.5 mg/L and contact time of 32.5 min. Based on the ANOVA analysis results, the f value in Fenton method indicates that the model is significant.
Conclusion: According to the results, Fenton oxidation process was selected as the optimum method to remove COD from synthetic wastewater containing Spiramycin antibiotic which may be applied as an efficient method for the treatment of wastewaters containing antibiotic.

Background and Objective: The Pesticides used in agriculture have caused great concern due to their adverse effects on human health. In this study, the effect of rinsing, crushing, filtering, clarifying with bentonite and pasteurization on the reduction of diazinon, ethion and phosalone during Asari grape juice was investigated.
Materials and Methods: Vineyard was sprayed during three growth stages before flowering, sour grape (ghooreh) and during grape ripening with phosalone, diazinon, ethion and in doses of 525, 600, 750 g of active substance per hectare, respectively. Twenty-four hours after the last spraying step, the grape sample was harvested and exposed to the process of rinsing (20-30 s), crushing, filtering, clarifying and pasteurizing. Then, the pesticides residue concentration was determined after each step by GC-MS/MS.
Results: The initial concentrations of diazinon, ethion and phosalone in unprocessed grape samples were 0.640, 0.716 and 0.550 mg/kg, respectively. The reduction values of diazinon during the juicing processes of rinsing, crushing, filtering, clarifying with bentonite and pasteurization, in comparison with the concentration of unprocessed grapes, were 25.72, 41.96, 74.54, 90.21 and 100% (not found), respectively; while these values were 9.78, 28.50, 69.45, 89.38 and 96.74% for ethion and 17.32, 28.47, 46.40, 80.25, 93.28% for phosalone, respectively. All processes significantly reduced insecticides residue.
Conclusion: Findings showed that the processes of grape juice production could significantly decrease the diazinon, ethion and phosalone residues.

Background and Objective: Pharmaceutical wastewater has a high level of pollution load that should be treated before discharging to the environment. Integrated processes using different mechanisms are one of the most fruitful methods in wastewater treatment. In this study, combined Integrated Fixed Film Activated Sludge (IFAS) and photocatalytic processes are utilized using of Fe₃O₄/TiO₂ nanocatalysts to decrease the COD value of pharmaceutical wastewater.
Materials and Methods: In this study, the variables of each process are optimized using Response Surface Methodology (RSM). In the IFAS process, the variables were dissolved oxygen (DO), media filling percentage and hydraulic retention time (HRT); while in the photocatalytic process, the effects of pH of wastewater, catalyst dose and reaction time were investigated.
Results: In optimal conditions (DO 3 mg/L, HRT 24 h and media filling percentage 65%), COD removal rate was obtained 59.15%. With the initial concentration of 1725 mg/L COD and the mentioned efficiency, the concentration of COD in the effluent diminished to 704 mg/L. However, in the photocatalytic process, during optimal conditions (pH 6.8, reaction time 105 min and catalyst dose 60 mg/L), The efficiency of the process was determined 81%, which by considering the input COD (704 mg/L), the output concentration was reduced to 134 mg/L.
Conclusion: According to the standards provided by the Environmental Protection Agency (EPA), the effluent from the combined process can be discharged into the environment.
 

Background and Objective: Based on its unique characteristics, oil industry wastewater must be treated before discharging into the environment. The study aimed to optimize the catalytic sonopraxone process in the treatment of petroleum wastewater using a statistical method.
Materials and Methods: The synthesis of Iron Oxide-Zinc Oxide was carried out by air oxidation and layer-by-layer self-assembly method. XRD, SEM, EDAX, FT-IR, BET, DRS, VSM and TGA techniques were used to investigate the structure. In this study, applied CCD method optimization of pH parameters, reaction time, ozone gas concentration, hydrogen peroxide concentration and catalyst amount in the process. In optimal conditions, BOD₅ and TPH removal values, reaction kinetics and synergistic effect of mechanisms were studied. COD, TPH and BOD₅ were measured by spectrophotometer (DR6000), GC-FID and incubator, respectively.
Results: The results indicated that the Fe₃O₄@ZnO structure is well formed. A quadratic model was proposed to model the process based on the correlation coefficient. Based on ANOVA analysis and p and f indices, the proposed model was reported to be significant. Optimum conditions include pH 6.4, ozone concentration 1.3 mg/L.min, hydrogen peroxide concentration 2.5 mL/L, reaction time 51 min and catalyst amount equal to 0.64 g/L. In these conditions, the amount of COD reduction was 82.3 and 70% theoretically and experimentally, respectively. Also, in optimal conditions, BOD₅ and TPH removal rates were 90.5% and 85.8%, respectively. The kinetics of the process follows the kinetics of the first order (R²=0.98) and the presence of different mechanisms together causes a synergistic effect and increases the efficiency of the process.
Conclusion: This process can improve the quality of oil effluent based on COD, BOD₅, and TPH removal.
 

Background and Objective: Visual pollution is one of the important components of the man-made environment in urban spaces. The purpose of this research was to investigate the visual pollution of workshops in Qom city using Expert Choice software and then the occupational ranking was done in terms of visual pollution.
Materials and Methods: This study was a descriptive-analytic cross-sectional study conducted in 670 trade units associated with 67 urban trade unions. The data collection tools were local visits, database preparation and completion of a questionnaire based on urban-environmental aesthetic criteria. The purpose of this study was to investigate the visual pollution caused by the occupations and workshops of Qom.
Results: The results showed that, in terms of total visual pollution, the units of oil changes with a total score of 1, materials and construction materials with 0.988, Smoothies with 0.980, Mechanics with 0.973, ceramic makers with 0.944, Chips and grills with 0.933, mosaics with 0.914, carwash with 0.885, stones cutting with 0.872, carpet with 0.870, trowel and blacksmiths with 0.857, burners with 0.830, battery makers with 0.825, iron manufacturers with 0.872 and manufacturers of general blinds and blinds with 0.753 were inadequate.
Conclusions: In order to reduce the number of visually impaired businesses in the short term, continuous inspections of businesses must be undertaken and, in the long run, by organizing the program, the polluting industries must be transferred out of the city.
 

Background and Objective: Pharmaceutical compounds can cause potential risks to aquatic and terrestrial organisms. So far, different methods have been used to eliminate these pollutants, photocatalytic processes are one of the most efficient processes to eliminate pharmaceutical compounds. In this study, the efficiency of a novel MOF-based nanocomposite, PMo/UiO-66 as a photocatalyst for amoxicillin degradation under visible light irradiation was evaluated.
Materials and Methods: The study of the chemical decomposition of amoxicillin using the PMo/UiO-66 system was conducted at different stages. First, the PMo/UiO-66 MOF nanocomposite was synthesized using the solvothermal method, then the properties of the synthesized nanocomposite were investigated using XRD, FTIR, and SEM techniques. The effect of different operational parameters such as pH (3, 6, and 9), catalyst concentration (15, 20, 25, and 30 %w/w), initial concentrations of amoxicillin (20, 30, 40, and 50 mg/L) at different times on the removal efficiency was investigated. The reusability of the catalyst for four cycles was assessed.
Results: The results showed that PMo/UiO-66 nanocomposite at pH 6, 25 %w/w nanocomposite concentration, and the amoxicillin concentration of 20 mg/L led to complete decomposition of amoxicillin after 120 min. The kinetic of amoxicillin removal followed the first-order model. Reusability tests showed that the photocatalytic efficiency of the synthesized catalyst was not substantially reduced after four cycles.
Conclusion: The current study confirmed that the PMo/UiO-66 system has an appropriate efficiency for photocatalytic removal of amoxicillin under optimized test conditions.

Background and Objective: Soil contamination with heavy metals is the most important challenge and common environmental, economic, and public health issue in the world. Therefore, this research was conducted to evaluate the contamination and source identification of Fe, Zn, Cd, and Cr in the surface soils of Khorramabad county, west of Iran in 2020.
Materials and Methods: In this descriptive study, after dividing the study area into 11 homogeneous units, a total of 65 surface soil samples were collected. After preparing the samples, the content of the elements was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, enrichment factor (EF), pollution factor (CF), and Nemrow integrated pollution index (NIPI) were calculated. Statistical analyses of the data were performed using SPSS statistical software.
Results: The results showed that the average content of Fe, Zn, Cd, and Cr (mg/kg) in soil samples were 3.14, 1.13, 0.021, and 0.529, respectively. The EF values showed that the enrichment of Zn, Cd, and Cr was "extremely severe" and the average values of EF for the elements followed the descending order of Cd > Cr > Zn. The average values of CF and NIPI varied from 3.30×10^-5 to 0.182 and 0.043-0.136, respectively, indicating the level of "low pollution" and quality conditions of "no pollution" in all the studied stations. Based on the results of multivariate statistical analysis (PCC, PCA and HCA), Fe has a geological origin; while, Zn, Cd, and Cr mainly originated from a combination of geological processes and anthropogenic activities.
Conclusion: Although the average values of CF and NIPI showed that the study area has an acceptable soil quality, the values of EF indicated the impact of anthropogenic activities on soil contamination. Therefore, regular and periodic monitoring of soil samples as well as management and control of pollutant emission sources is recommended for maintaining environmental and human health.

Background and Objective: Vacuum Ultraviolet (VUV)-based advanced oxidation is a new category of advanced purification processes, so this study aimed to compare the efficiency of VUV and Ultraviolet-C (UVC) processes in combination with H₂O₂ and PMS in degrading Remdesivir.
Materials and Methods: The photoreactor was investigated with VUV and UVC lamps in combination with H₂O₂ and PMS for Remdesivir degradation. Also, the effect of variables such as solution pH, H₂O₂ dose, Remdesivir concentration, the presence of radical scavengers and anions, as well as hydraulic retention time was considered in the continuous process of Remdesivir removal.
Results: The findings showed that the optimal pH in the processes of VUV, UVC, and their derivatives was equal to 7. By adding 1 mM of PMS and H₂O₂ to the VUV process, the degradation efficiency of Remdesivir was increased from 92.2 ± 0.4% to 98.3 ±2.1% and 100 ± 0.3%, respectively, after 30 min. Also, in the UVC process combined with H₂O₂ and PMS, the degradation efficiency reached 77.8 ± 1.5 and 85.2 ± 1.3% after 40 min, respectively. The degradation kinetics in the examined processes were as follows: VUV/H₂O₂ > VUV/PMS > VUV > UVC/H₂O₂ > UVC/PMS > UVC. The hydroxyl radical was the main reactive oxygen species that led to the decomposition of Remdesivir. The continuous operation of VUV/H₂O₂ showed that the removal efficiency of Remdesivir reached 94.7 ±0.8% after 40 min.
Conclusion: Considering the high rate of Remdesivir degradation by adding H₂O₂, the VUV/H₂O₂ process can be introduced as an efficient technology for the removal of antiviral drugs.
 

Background and Objective: Compliance with the principles of environmental health is of particular importance in any gathering ceremony. This issue needs more attention in the Muharram and Safar mourning ceremonies due to the position of health in Islam and the presence of different populations in this ceremony. Based on this, the present study was conducted with the aim of environmental health management during Muharram and Safar days using the Analytic Hierarchy Process.
Materials and Methods: According to the main purpose of the study, a literature review was done. Then, a team of experts was formed and criteria, sub-criteria and programs related to the purpose of the study were determined by brainstorming, and the relevant questionnaire was prepared and after completion by 25 experts, the relevant criteria were prioritized using the Analytic Hierarchy Process.
Results: Based on the weighting with the Analytic Hierarchy Process method, the highest score (0.441) was awarded to the health inspection criteria, and then the administrative coordination criteria(0.186), education (0.182), reporting (0.169) and finally the support and services criterion (0.022) were prioritized.
Conclusion: The results of the study indicate the emphasis on environmental health management during the Muharram and Safar mourning ceremonies from the point of view of experts, that compliance with the three principles of health inspection, administrative coordination and continuous training has the particular importance.
 

Background and Objective: Waste management is a crucial aspect of sustainable city development due to the increasing population, urbanization expansion, and changes in consumption patterns. The purpose of this study is to identify the waste landfill in Bushehr city by considering the relationships between various criteria using the DANP (DEMATEL-ANP) method.
Materials and Methods: 17 criteria were identified to identify the suitable landfill. The weighting of these criteria was done by DANP integrated multi-criteria decision-making technique. The internal relationships of the criteria and the causal relationships between the criteria were also determined. Then, these weights were multiplied in the spatial layer of each of the criteria in the environment of geographic information systems.
Results: The most crucial criterion for selecting a suitable location for urban landfill is land use, followed by the criteria of distance from residential areas, tourist places, and the road. The study identified and evaluated five locations in Bushehr city as potential landfills based on these criteria. The eastern and southeastern parts of Bushehr city emerged as the most suitable locations for landfill among the evaluated sites.
Conclusion: The DANP model proves highly effective in identifying landfills and offers a framework for addressing issues related to waste landfill selection. This research can serve as a valuable guide for planning and locating waste landfills, providing a basis for addressing both theoretical and practical challenges associated with landfill management.
 

Background and Objective: The increase in waste at integrated urban waste centers, along with the problems and adverse environmental consequences due to their inappropriate establishment have become more apparent. This research was conducted with the aim of determining and investigating environmental pollution in urban waste integration management centers.
Materials and Methods: This research investigated the environmental pollutants in the integrated waste center in Koohak at various distances ranging from 0 to 900 meters. Four main criteria—waste, water pollution, air pollution and sound pollution—were determined, each with 16 sub-criteria. The map of each criterion and sub-criteria were multiplied by the coefficients they received from the weights obtained using the Analytical Network Process (ANP) method. By combining the criteria using the Weighted Linear Combination (WLC) method and superimposing them, finally, the studied area was ultimately classified into three classes: inappropriate, medium, and suitable.
Results: Air pollution, with a weight of 0.26, had the highest rating compared to the other three criteria. Noise pollution (0.25), water pollution (0.24) and waste-related criteria (0.23) were ranked next. The results of the Kruskal-Wallis test indicated a significant difference in pollutant concentrations between different stations (p<0.05). Additionally, the results show that the average concentration of pollutants at distances of 0-300 meters differed significantly from those at all other distances (p<0.05). After determining the suitable zones using the WLC method, the results showed that 62.5 percent of the criteria were approved by the environmental organization.
Conclusion: By examining the results of the methods used in this research, it can be concluded that the combination of ANP and WLC methods provide effectivee results. However, uncertainty in subjective decisions and time constraints in decision-making have posed challenges in assessing waste collection in integrated urban waste centers.
 

Background and Objective: Composting is a sustainable solution for recycling organic solid waste (OSW). Various compounds can be used to enhance the quality of compost. This study aimed to investigate the effects of zeolite on the physical and chemical characteristics of compost produced through the anaerobic process.
Materials and Methods: This analytical study was conducted in 1402 at Kimia Sabzevar Company, located 5 km from Rudab Road. Cow manure and natural clinoptilolite zeolite were used in varying proportions (0%, 5%, 10%, 15%, and 20% of the total reactor volume) to prepare fertilizer via the anaerobic method. After 30, 45, and 60 days, a total of 90 samples were collected and sent to the laboratory for analysis. Parameters such as pH, electrical conductivity, temperature, carbon-to-nitrogen ratio, and nitrate content were measured to evaluate the quality of the fertilizer product.
Results: The results showed that in the early stages, pH changes were less pronounced in treatments with varying zeolite percentages, ranging from 7.9 to 8.57. The addition of zeolite in the composting process influenced temperature dynamics, with higher zeolite percentages maintaining elevated temperatures. Moreover, the nitrate content increased by 15% during the process.
Conclusion: The findings indicate that adding zeolite to fertilizer enhances temperature stability, accelerates the composting process, and reduces the time required for fertilization. Additionally, zeolite improved the physicochemical properties of the fertilizer produced through the anaerobic process.