سید نادعلی علوی بختیاروند

 Composting process as a biological method in waste management has many problems including odor emission. Ammonia, volatile organic compounds and hydrogen sulfide are factors that cause odor. The purpose of this study is to review studies on odor emission and strategies of reducing odor emission in the composting process.

 In this study, the keywords including Odor compost, Food waste composting, Odor emission composting process and Odor composting were searched in scientific databases such as Google scholar, Scopus, ScienceDirect, PrpQuest and PupMed. As a result of this search, more than 200 articles were identified and extracted.

 The results of the investigated studies showed that the major components of odorous gases in the composting process are ammonia gases, hydrogen sulfide and VOCs. Studies on controlling and reducing the emission of odorous gases from the composting process are included in two groups: improvement of the composting process by adjusting environmental conditions and using additives with the aim of reducing odor production.

 The review of studies showed that by adjusting the physical and chemical factors of the composting process, it is only possible to reduce only one of the odorous gases, and due to the composting process is a biochemical procedure and the sensitivity of microorganisms, as well as the production mature fertilizer, the adjustment of the composting conditions is limited and the operable range is very narrow so principally, this method is difficult to control odor in practice. Therefore, the use of additives is suggested as a suitable strategy to control odor emission in the composting process. These additives reduce the odor emission in the composting process by creating porosity, gas absorption, and gas precipitation. 

Increasing global consumption of fossil fuels leads to greenhouse gas emissions, climate change and environmental pollution. Agricultural, animal and food industrial waste is one of the main sources of pollution. The bioethanol industry is one of 17 highly polluted industries. In the process of producing bioethanol, vinasse is produced, and so far 22.4 Giga litter of vinasse has been produced worldwide.With fossil fuel resources running out, energy production from renewable sources, including organic waste, has been considered in recent years and has transformed biological hydrogen production into a new approach to replace it with fossil fuels. The purpose of this study was to evaluate Biohydrogen production from Vinasse bioethanol processing industry as clean and renewable energy.

In this review study conducted in 1398, 150 indexed articles from the past 15 years were used in the databases of ProQuest, Science Direct, Pubmed, Google Scholar and Scopus.

The results showed that vinasse is the most effective organic material for high-efficiency Biohydrogen production and dark fermentation hydrogen is the most promising biological hydrogen production method. Microbial species, reactor type, pH, temperature, substrate type and concentration, organic loading rate (OLR), hydraulic retention time (HRT), nitrogen, phosphate and iron concentrations are among the parameters influencing the process to maximize biohydrogen productivity and efficiency and concentration. High volatile fatty acids are also a major inhibitor of Biohydrogen production.

Compared to the thermal energy content of methane, ethanol and gasoline, hydrogen thermal energy is high (142 kj/g) and water is the only by-product of hydrogen burning. Anaerobic treatment is the most effective way to reduce the pollution of Vinasse. In addition to reducing environmental pollution, the economical result of Biohydrogen production as a clean energy source is that by optimizing the operating conditions of the process we can achieve maximum efficiency and productivity of Biohydrogen production.

Solid waste management is one of the biggest environmental challenges facing the world today due to the increasing population and urbanization, and use of earthworms has been receiving considerable attention in recent years for waste disposal and convert its into useful materials .The aim of the study was produced vermicompost from bagasse and kitchen waste.
In this experimental was prepared the bagasse and kitchen waste treatment in three replication (a total of 9 units Laboratory). parameters such as pH , total carbon , total nitrogen , phosphorous and potassium was measured for 60 day.
In the end, pH did not change as compared to the initial level and trend. The results showed decreased in total carbon, total nitrogen , C/N and increased , phosphorous and potassium .the highest phosphorous and potassium content obtained 1:2 ratio.
In the vermicomposting process, the best of mixture bagasse with kitchen waste was observed in 1:2 ratio and superior to other treatment.

Soil polluted with total petroleum hydrocarbon (TPHs) is a great threat to human health. Phytoremediation, the use of vegetation for treatment of contaminated soils, is an attractive and cost-effective alternative to reduce pollutant from soil. This paper evaluates the effects of the plant and nutrients on the removal of TPHs from soil. Soils were collected at depth of 0-30 cm, and then polluted with 1 and 2.5 % w/w of crude oil. After preparing the experimental pots, Rhizosphere microbial number, plant biomass, and residual TPHs were determined. TPHs and heterotrophic bacterial number were measured by GC and HPC method respectively. Data were analyzed using the Statistical Package for Social Sciences (SPSS 17 for Windows) software and Excel. It was found that the average percent of TPH removal in planted soil (28.42%) was higher than that in unplanted soil (12.2%) (p<0.05). Moreover, the average percent of TPH removal in treatments received nutrient and free nutrient treatments was 35.5and 17.7% respectively. Generally compared with the other studies, high clay and salinity of the experimental soil had a negative effect on phytoremediation efficiency. Finally, regarding to the high clay and salinity of the experimental soil, the phytoremediation efficiency was relatively desirable.

Petroleum contaminated soil is an environmental problem that affects human health. Phytoremediation is a cost-effective method for removal of petroleum from soil. This study evaluated the effects of the plant and nutrients on the removal of total petroleum hydrocarbons (TPHs) from the soil.

Soils were collected from Ahwaz desalting unit No. 2 and then polluted with 2. 5% w/w of crude oil. Microbial number and residual TPHs of the studied pot experiments were determined at day 0 and 90. TPHs and heterotrophic bacterial number were measured by gas chromatography (GC) and heterotrophic plate count (HPC) method، respectively.

The average percentage of TPH removal in the rhizosphere soil (≈ 20%) was higher than those in the non-rhizosphere soil (≈ 7%). In addition، the average number of heterotrophic bacteria in the rhizosphere soil (7. 14 CFU/g) was higher than in the non-rhizosphere soil (6. 16 CFU/g). Moreover، the TPH removal and microbial number in the soil that received nutrient were higher than in the free-nutrient soil.

Although high clay and salinity of the soil had an inhibitive effect on phytoremediation efficiency، results showed a native plants performed phytoremediation properly even in improper condition of environment.

Fluoride is one of the most important elements in the composition of teeth and bones. This element can enter the body via different ways. However, drinking water is the most important way to receive fluoride by a lot of people. An Increase in fluoride level in the body causes dental fluorosis and its absence leads to teeth decay. Standard rate of fluoride in drinking water is determined by the ambient air temperature. In general, standard level of fluoride in drinking water in winter, mainly due to less water consumption, is high, and in summer, due to more consumption of water, is not remarkable. In this study, fluoride has been determined in 4 groundwater and surface water resources on 1.5 year period. From each resource every month, 4 samples were obtained and analyzed according to SPANDS method. Results shownd that fluoride concentration in Sanandaj water resources (0.31 mg/l average) was less than the recommended standards. Fluoride concentration did not show significant differences in different water resources of this city (p-value> 0.05). Fluoride levels in Sanandaj drinking water are low. Therefore, according to cold climate of Sanandaj and low Per capita water consumption in winter and low fluoride capture from other sources, fluorination of drinking water or using fluoride mouthwash are recommended to provide the required amount of fluoride for the people of Sanandaj, especially the children.

Backgrounds and Selection of proper coagulants for turbidity removal and determination of effective methods to reduce coagulants dose and related costs in water treatment plants is of critical importance. The present study investigates the effect of returned sludge on improving the performance of poly-aluminum chloride (PAC) in turbidity, coliform bacteria, heterotrophic bacteria removal from drinking water during rapid mixing phase. In order to determine the optimal returned sludge volume injected during rapid mixing with PAC for turbidity, total coliform and hetrophic bacteria, experiments were conducted based on variables such as injected silt volume (from 0 - 125 ml), and varying turbidities from 58 - 112 NTU. At the end of each JAR experiments, remaining turbidity, microbial parameters of samples were measured. Coagulant efficiency in turbidity removal and microbial parameters were determined by Covariance, Duncan analyses and graphs were drawn by MS Excel. The results statistically showed significant among variables (P<0.05). The results showed that the maximum turbidity removal efficiency of 98.92 at 30 ppm was 10 ml while the maximum turbidity removal efficiency of 98.31 at 10 ppm was 4 ml. The maximum total coliform removal efficiency of 95.68 obtained for 10 ppm in 10 cc injected sludge volume. This study shows that addition of returned sludge to flash mixing can reduce the turbidity of samples.