Background: The entrance of untreated wastewater or disposal LEACHATE to water resources such as surface water, groundwater or irrigation water increases the risk of contaminant accumulation. Removal or deduction of water contaminant concentration is then crucial before entering water to the natural resources or its transfusion directly to the soil as irrigation water. Four studies were carried out in a pilot plant to evaluate the effect of natural zeolite to decrease chemical and biological index of COMPOST factory LEACHATE. Land treatment was considered as the main strategy; however, some pounding and column experiment was implemented as well. Wastewater chemical and biological indexes were analyzed. These indexes consisted of Na, K, Mg, Ca, Co3, HCO3, Ni, Cd, Pb, Cr, chemical oxygen demand (COD), fecal coliform and total coliform (TC). In addition, soil was analyzed for EC, pH, cation and anion.Results: In the first study, three types of zeolite derived from Semnan, Mashhad and Miyaneh mines were tested with four sizes (70, 140, 270 and 840μm) at 25°C in summer 2007. It was concluded that high value of the cation concentration in the LEACHATE causes neither adsorption of remaining cation nor heavy metals. There was no statistically significant difference between the zeolite sizes and the heavy metal adsorption. The results also showed that the adsorption ratios were 52%, 23% and 40% for Na, Ca and Mg, respectively. In the second study, a loamy sand soil was enriched by adding 5% and 10% of the zeolite. The result uncovered that adding 10% of the zeolite to the soil brings about more elements’ absorption in comparison to application of the 5% zeolite. Irrigation with the LEACHATE reduced soil specific yield significantly. In the third study, a complete randomized design experiment was used with six treatments (two kinds of soil, loamy sand and clay loam, and three levels of zeolite, 0%, 5% and 10%) and three replications performed in the lysimeter size. The results revealed that irrigation with the LEACHATE reduces soil bulk density, infiltration rate and saturated hydraulic conductivity. Heavy metals could not be absorbed by loamy sand soil, whereas clay loam soil had a high ability to absorb heavy metals and reduce the salinity. In loamy sand and clay loam soil, 10% zeolite had a significant effect on heavy metals’ absorption. The result of subsequent study (the same setup as the third study) exhibited the fact that the COD was significantly decreased by application of 5% zeolite, whilethis reduction occurredvia applying 10% of zeolite in TC.Conclusions: In short, this research indicated that the wastewater can be treated in a simple, economically process of land treatment through application of a clay loam soil texture with a cation pre-treatment.

Continuous population growth and enhancement of human life have led to an increase in waste production. Thus, waste management has become a problem of many countries. Over recent years, organic wastes management policies have been increasingly tending toward recycling. COMPOST process is widely applied to transform wastes into fertilizers, in which LEACHATE management is a problem due to its adverse effects on the environment and human health. Control, collection, disposal, and treatment of LEACHATE requires a special attention to prevent soil, surface and ground water contamination. The LEACHATE contains toxic organic compounds and phenolic compounds. The first are resistant to biodegradation, nitrogen, aromatic and the latter threats human and aquatic life. This is why the LEACHATE requires chemical treatment including advanced oxidation processes (AOPs). Combining UV radiation by the hydrogen peroxide (H2O2) is one of the advanced oxidation processes. During photolysis, UV radiation directly breaks down a complicated compound to more simple ones, by more energy than the compound binding energy. High energy cnsumption enhances the costs of this method. So it can be improved economically by controling parameters including pH and UV contact time that affect oxidation process.The LEACHATE effluent was prepared from COMPOSTing plant, Golestan, Iran. The LEACHATE was characterized immediately after transferring to the lab. Furthermore, samplings were carried out three times to measure COD, BOD, total suspended solids (TSS), and turbidity of the stored samples. Total nitrogen contents of unviable cells were analyzed by Kjeldahl determination (2300 Kjettec Analyzer Unit, Foss Tecator, Sweden). The RSM approach used in the present study was under a CCD approach including four independent variables; initial pH, H2O2 and UV contact time. The design consisted of 2k factorial points augmented by 2k axial points and a center point where k is the number of variables. The two operating variables were considered at three levels; low (-1), central (0) and high (+1). With the RSM approach, ANOVA was carried out for a second-order response surface model. The significance of each coefficient was determined by the F -values and the values of probability (prob>F). The larger the magnitude of the F -value and the smaller the p -value, the more significant the corresponding coefficients. Values of ‘ prob>F’, less than 0.0500, also indicate highly significant regression at a 95% confidence level. A total number of 20 experimental runs was set.Optimal condition obtained for H2O2/UV process were of initial pH 7.5, hydrogen peroxide of 2.3 mL/L, and UV-contact time of 95 min. In these conditions, the removal rates of COD and color and turbidity for H2O2/UV process were 12.32%, 20.83%, and 8.68 NTU, respectively. The RSM applied in this study can present the effects of the operating variables as well as their interactive effects on the responses. In the present study, most effective factors on the advanced oxidation process including pH, hydrogen peroxide dosage and UV-contact time were tested. The results indicated that the H2O2/UV process has been successful in reducing turbidity but not in COD removal efficiency.

Anaerobic treatability of real COMPOST LEACHATE was assessed using laboratory-scale anaerobic sequencing batch reactor at mesophilic conditions. Interventional study was conducted at wide range of organic loading rate 0.93–25 g l-1 day-1 by varying hydraulic retention times 23 and 12 h. Initial chemical oxygen demand (COD) was 1.85-25 g l-1. pH variations; total, soluble (SCOD), readily biodegradable (rbCOD) chemical oxygen demand; volatile fatty acids degradation; biogas production; and methane fraction were considered in this study. The organic matter removal efficiencies were in the range of 76-81% depending on loading rates applied. The maximum volumetric methane production rate of 5.7 l CH4 l-1 day-1 was achieved at the loading rate of 19.65 g l-1 day-1. About 85% of removed organic matters during the biodegradation were converted to the methane. The results have shown that the anaerobic batch reactor could be an appealing option for changing COMPOST LEACHATE into the useable products such as biogas and other energy-rich compounds, which may play a serious role in meeting the world’s ever-increasing energy requirements in the future.

A lab-scale SBR equipped with a flat sheet membrane in submerged configuration that is named MSBR was used for treatment of COMPOSTing LEACHATE. It was fed by biologically treated LEACHATE with overall 70-1360 mg/L Chemical Oxygen Demand (COD). The values of pH, Electrical Conductivity (EC), and Dissolved Oxygen (DO) were monitored routinely. However, analysis of total COD, Soluble COD (SCOD), Biological Oxygen Demand (BOD5), Total Suspended Solids (TSS) and Volatile Suspended Solids (VSS) were done in feed and filtrate, whenever the system reached steady state twice a week for about 6 months. In all loading rate, BOD5 concentration was less than standard limit. The removal efficiency of total COD increased in bioreactor with time in all experiments was up to 80%. Influent SCOD varied spectacularly (50-1050 mg/L) due to the LEACHATE collection during different seasons but in the effluent it remained relatively stable. About 60% of the feed SCOD was non biodegradable type that was separated by the membrane. Up to 99 % further solids was removed with micro pore membrane which might be mainly included in colloidal solids. The value of EC for the LEACHATE sample was 0.86-4 mS/cm in 22oC which decreased by membrane significantly. It was concluded that, MSBR as a versatile technology with high throughput could treat COMPOSTing LEACHATE below the standard limit if used after proper processes.

The moisture content of urban soild wastes in Iran is very high. A large volume of Leacahate is, therefore, produced in the process of converting these wastes into COMPOST. The leach ate contains relatively large amounts of organic matter, plant nutrients, soluble salts as well as small amounts of some heavy metals. The effects of urban solid waste leach ate on growth and yield of corn and heavy metals and nutrients concentrations in plant as well as the effects of leach ate residual on soil were studied in field trial conducted in one site (Zeinal) in central Iran (Isfahan). The treatments included applications of 0, 400 and 800 metric tons of LEACHATElha as the main plots and two leaching treatments (0 and 15 cm water height)as the sub-plots in a split plot design. Application of the leach ate decreased crust formation and greatly improved germination and growth of corn. Biological yield of corn increased from 6.8 to 11.4and 8.9 tonslha for 400 and 800 tons/ha of LEACHATE applications (as compared to the control field ),respectively. Leaching increased corn yield. Uptakes of N , P , K , Fe , Mn , Zn and Cu by corn increased as a result of LEACHATE application. Concentrations of Fe , Mo , Zn , Cu and Cr in plant tissues also increased but no toxic symptoms were observed in plants. Concentrations of Pb, Cd, Cr, Co , and Ni in aerial tissues of corn did not increase as a result of LEACHATE application .The residual effects of LEACHATE application on soil were a decrease in pH and corresponding increases in organic matter content, in electrical conductivity and in available amounts of N,P,K, Fe ,Mn , Zn , and Cu. It is concluded that COMPOST LEACHATE has the potential to be used as an organic liquid fertilizer and soil amendment to improve soil productivity at least for a limited period of time.

Application of COMPOST from solid waste refuses is common in agricultural lands, but, solid waste has high moisture percentage. During the process of COMPOSTing, it produces considerable amount of LEACHATE and if not properly collected, it can cause environmental problems. Therefore, a greenhouse experiment was conducted to study the effects of municipal waste LEACHATE and solid waste COMPOST on yield and yield components of wheat. Treatments were four irrigations with different LEACHATE to water ratios (T0=water, T2= 20%, T4=40%, T6= 60% V/V basis) and a loamy soil with 15 ton per hectare solid waste COMPOST in a completely randomized design with three replications. Results indicate that different LEACHATE to water ratios and solid waste COMPOST had significant effects on yield and yield components of wheat. Yield and yield components were decreased with increasing ratios of LEACHATE to water more than 20/80 ratio. The highest yield and yield components were obtained in 20/80 LEACHATE to water ratio and in soil with COMPOST. Furthermore, the comparison of control soil with and without COMPOST revealed a positive effect of COMPOST on number of grain per spike, spike length, grain weight per spike, grain and straw yield per pot, probably. Due to increase in organic matter content and more availability of nutrient elements in soil and soil physical improvement. LEACHATE to water ratio of 20/80 (T2) showed a more positive effects with respect to plant height, number of grain per spike, grain weight per spike, 1000 grain weight, grain and straw yields per pot than the addition of COMPOST effects.

COMPOST LEACHATE is a liquid resulting from physical, chemical and biological decomposition of organic materials. The main objective of this study was to evaluate the influence of LEACHATE COMPOST on the physical, hydraulic and soil moisture characteristic curves. Also, the effect of LEACHATE on the aerial organ fresh weight of corn was investigated. LEACHATE was added to clay loam and sandy clay loam soils at the rate of zero, 1. 25 and 2. 5 weight percent. The soil water characteristic curve and the estimation of the parameters of the van Gnuchten and Brooks and Corey models were performed using RETC software. LEACHATE increased the bulk density and decreased the available water of the clay loam soil. Only 1. 25% of the LEACHATE increased the available water in the sandy clay loam soil. Two levels of LEACHATE decreased the bulk density of sandy clay loam soil. LEACHATE decreased the saturation hydraulic conductivity of the clay loam and increased this parameter of sandy clay loam soil. LEACHATE was more successful in increasing the aerial organ fresh weight of corn in the sandy clay loam soil. Therefore, LEACHATE was more useful in sandy clay loam than in clay loam soil, and 1. 25% treatment was better in the sandy clay loam soil. Also, the used LEACHATE increased the repellency of both soils. LEACHATE caused the parameters of van Gnuchten and Brooks and Corey models to increase, as compared to the control in both soils.

This study was conducted to evaluate the effect of Municipal waste COMPOST LEACHATE (MWCL) on Capsicum annum plant and chemical properties of a clay loam soil with five ratios of MWCL to irrigation water (0, 20, 40, 60 and 100 percent) treatments each with three replications by using a completely randomized factorial design under greenhouse condition. Electrical conductivity, organic matter and concentration of available nutrients of N, P, K, Ca and Mg in soil increased with increasing percentage of MWCL, but pH of the soil was decreased. Increased concentrations of MWCL caused drastic decreases in plant growth. The MWCL of 100 percent treatment caused the seedlings to be died off. The treatment with 20 percent MWCL increased plant fresh and dry weight, fresh and dry weight of green chili. Plant content of N, P and K increased with increasing concentrations of MWCL. The use of 20 percent MWCL seems to cause increasing green chili yield. An application of high concentrations of MCWL to soil is not recommended due to increase of EC of soil solution.

Application of COMPOST and COMPOST LEACHATE as organic fertilizers can improve plant growth, nutrients uptake and increase phytoavailability of nutrients in soil. A factorial experiment (4×4×2) was conducted in a completely randomized design to evaluate the effect of COMPOST and COMPOST LEACHATE on growth and chemical composition of barley and bioavailability of some nutrients in calcareous clay loam soil and sandy soil under greenhouse conditions. Treatments consisted of four levels of COMPOST (0, 15, 30, and 60 g kg-1), four levels of COMPOST LEACHATE (0, 10, 20, and 40 g kg-1), and two culture mediums (clay loam soil and sandy soil) with three replicates. Results indicated that application of COMPOST and COMPOST LEACHATE significantly increased barley shoot dry matter, the number of tillers, spikes and grain yield in clay loam soil and sandy soil. The maximum barley shoots dry matter and numbers of tillers in both culture mediums were obtained at the highest level of COMPOST or COMPOST LEACHATE, and the maximum number of spikes and grain yield were obtained at the lowest level of COMPOST or COMPOST LEACHATE. Application of COMPOST in clay loam soil and sandy soil increased shoot and root concentrations of nitrogen (N), phosphorus (P), Iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu). However, addition of COMPOST LEACHATE only increased shoot concentrations of Fe and P. Increasing COMPOST levels increased post harvest concentrations of NO3- N, P, Fe, Mn, Zn, Cu and also electrical conductivity and organic matter content of clay loam soil and sandy soil. Addition of COMPOST LEACHATE significantly increased concentrations of Fe, Zn, Cu and also electrical conductivity and organic matter content of both culture mediums. In both culture mediums and both COMPOST and COMPOST LEACHATE treatments, post harvest concentrations of micronutrients were above critical levels. Therefore, addition of these nutrients is not required for the next cultivation. Generally, COMPOST and COMPOST LEACHATE are appropriate organic fertilizers for barley production; however, high salinity level in COMPOST LEACHATE, the rate and frequency of LEACHATE application, particularly in sand, needs intensive control and monitoring. Prior to any fertilizer recommendation, the results of this study need to be verified under field conditions, as well.

The amount of municipal waste LEACHATE produced during the process of COMPOSTing of solid waste refuse is high, due to its higher moisture content. Therefore, improper collection methods and uses can cause environmental problems. This study was conducted in order to investigate the effect of municipal soild waste COMPOST  LEACHATE (MSWC LEACHATE) on yield and yield components of wheat (Triticum aestivum) with four irrigation treatments of different LEACHATE-to-water ratios (T0=water, T20=20%,T40=40%, T60=60% V/V basis) in a completely randomized design with three replications under greenhouse conditions. Results obtained indicate the significant effect of different LEACHATE to water ratios on ECe, pH, TN, available P and OC of soil, yield and yield components of wheat. ECe, TN, available P and OC of soil increased, but the soil pH decreased with MSWC LEACHATE concentrations and the maximum was recorded for the T60 treatment. The number of grains per spike (more than 1.4 times), plant height (13.8%), grain weight per spike (more than 1.6 times), grain and straw yields (more than 1.5 and 1.6 times, respectively), and the ratio of grain weight to straw weight in a LEACHATE-to-water ratio of 20/80 (T20) treatment increased when compared to their respective controls and the other treatments (p≤0.05). Spike length and 1000 grain weight in a LEACHATE-to-water ratio of 20/80 (T20) treatment were not significantly different from their respective controls. Increasing the LEACHATE concentrations to more than 20%, reduced yield and yield components of wheat compared to control, probably due to a soil salinity increase and its negative impacts on the parameters studied (p≤0.05).