• Journal of Korean Society on Water Environment
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• v.20 no.5
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• pp.457-465
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• 2004

The objective of this study is to evaluate the possibility to apply the Moving Bed Biofilm Reactor(MBBR) in the activated sludge treatment process with existing aerobic HRT. Optimal operation conditions were assumed according to the analysis of organic matter and nutrients removal efficiencies depending on loading variations. The process was operated under different conditions: RUN I(HRT=7.14hr, $I{\cdot}R=100%$), RUN II(HRT=6.22hr, $I{\cdot}R=100%$), RUN III(HRT=6.22 hr, $I{\cdot}R=150%$), RUN IV(HRT=6.22hr, $I{\cdot}R=200%$), the TBOD removal efficien cies are 88%, 88.5%, 94.6%, 97.6%, respectively. Overall TSS removal efficiency is 90%, and it is increasing in RUN IV. In the case of Nitrogen, the highest removal efficiency of 90% was observed in RUN III and RUN IV, Nitrification and Denitrification rates are 0.013-0.016kg $NH_3-N/kg$ Mv-d and 0.009-0.019kg $NO_3/kg$ Mv-d, respectively. Phosphorus removal efficiencies are 89.6% in RUN I, 91.5% in RUN II, 84.3% in RUN III, and 76.4% in RUN IV. The process under shorter SRT yields better performance in terms of phosphorus removal. It was noticed that to achieve the effluent phosphorus concentration ofless than 1mg/L and removal efficiency higher than 80%, SRT should not be longer than 10 days. Experimental result shows that HRT of 6.22 hours is suitable for this treatment process, and, as a result, the aerobic reactor including moving media and DO depletion tank have a sufficient effect to the process performance.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.29-37
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• 1994

Anaerobic treatment of wastewater of the red- bean processing industry was carried out and discussed an anaerobic sludge bed reactor( ASBR) as a preliminary study to evaluate applicability of given processes. The dimension of reactor were same as 0.09m- ID$\times $1.5m- height. The type of substrate and the hydraulic retention time( HRT) were considered as experimental variables. The synthetic wastewater with glucose in the laboratory, the wastewater from the red bean processing industry mixed with synthetic wastewater with variation of mixing percent were fed as substrate. The hydraulic retention time was changed from one day to five days. The gas production, the methane content in produced gas, efficiencies of COD removal and 55 removal were evaluated as principal characteristics. With synthetic wastewater as a substrate and at a hydraulic retention time of one day, characteristics of ASBR was the gas production(12$\ell$/day ), the methane content of produced gas(60%), the efficiency of COD removal(92%) and 55 removal(30%). With the real wastewater and at a hydraulic retention time of one day, the gas production and the efficiency of COD removal of the ASBR decreased with the proportion of real wastewater. The gas production and the efficiency of COD removal with real wastewater only was decreased to 70% and 87% of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. With real wastewater only as a substrate in the ASBR, the gas production was decreased with an increase of HRT, but the efficiency of COD removal increased with HRTI like the usual trend reported. As a conclusion, the wastewater of the red- bean Processing industry could be treated by anaerobic digestion successfully in the ASBR.Anaerobic treatment of wastewater of the red- bean processing industry was carried out and discussed an anaerobic sludge bed reactor( ASBR) as a preliminary study to evaluate applicability of given processes. The dimension of reactor were same as 0.09m- ID$\times $1.5m- height. The type of substrate and the hydraulic retention time( HRT) were considered as experimental variables. The synthetic wastewater with glucose in the laboratory, the wastewater from the red bean processing industry mixed with synthetic wastewater with variation of mixing percent were fed as substrate. The hydraulic retention time was changed from one day to five days. The gas production, the methane content in produced gas, efficiencies of COD removal and 55 removal were evaluated as principal characteristics. With synthetic wastewater as a substrate and at a hydraulic retention time of one day, characteristics of ASBR was the gas production(12$\ell$/day ), the methane content of produced gas(60%), the efficiency of COD removal(92%) and 55 removal(30%). With the real wastewater and at a hydraulic retention time of one day, the gas production and the efficiency of COD removal of the ASBR decreased with the proportion of real wastewater. The gas production and the efficiency of COD removal with real wastewater only was decreased to 70% and 87% of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. With real wastewater only as a substrate in the ASBR, the gas production was decreased with an increase of HRT, but the efficiency of COD removal increased with HRTI like the usual trend reported. As a conclusion, the wastewater of the red- bean Processing industry could be treated by anaerobic digestion successfully in the ASBR.

• Korean Chemical Engineering Research
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• v.53 no.1
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• pp.121-126
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• 2015

The objective of this study is to evaluate the catalytic potential of the porous material prepared from water treatment sludge. The textural properties of the catalyst were studied using $N_2$ adsorption and desorption isotherms, scanning electron microscope, and X-ray diffraction. The pellet-type catalyst prepared using water treatment sludge is determined to be a material that contains mesopores as well as micropores. The specific surface area of the catalyst is $157m^2/g$. Acidic characteristics of the catalyst are analyzed by temperature-programmed desorption of ammonia and infrared spectroscopy of adsorbed pyridine. 2-Butanol dehydration reaction was carried out in a fixed bed catalytic reactor. Yields of 1-butene, trans-2-butene, and cis-2-butene at $350^{\circ}C$ were 25.6 wt%, 19.2 wt%, and 29.9 wt%, respectively. This catalytic activity of the catalyst based on water treatment sludge in 2-butanol dehydration is due to the acid sites composed of Bronsted acid sites and Lewis acid sites. It was confirmed that the catalyst based on water treatment sludge can be utilized to produce $C_4$ olefin through butanol dehydration.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.242-249
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• 1998

The engineering aspect of water treatment processes in the recirculating aquaculture system was studied. To recycle the water in the aquaculture system, a wastewater treatment process was required to maintain high water quality for the growth and health of the cultured fish. In this study, three different biofilm processes were used to reduce the concentration of organic matters and ammonia from the recirculating water - two phase fluidized bed, three phase fluidized bed, and trickling filter. The objectives of this research were to evaluate the optimum treatment conditions of the biofilm processes for the recirculating aquaculture system, and thereby reduce the volume of biofilm processes, which are commonly used for the recycle water treatment processes for aquaculture. The result of this study showed that the removal efficiency of organic matters by trickling filter was found to be lower than that of the fluidized bed. In the trickling filter system, anthracite showed better organic removal efficiency than crushed stone as a media. In the two phase fluidized bed, the maximum removal efficiency of either organics or ammonia was obtained when both the packing rate of media was maintained to $40\%$ of total reactor depth excepting sediment zone and the bed expansion rate was maintained to $100\%$. When 100 tilapia (Oreochromis niloticus) of each average 200g was reared, the pollutant production rate was 0.07g $NH_4\;^+-N/kg$ fish/day and 0.06g P04-3-P/kg fish/day, and sludge production rate was 0.39 g SS/kg fish/day. In the two phase and three phase fluidized bed, the volume of water treatment tank could be calculated from an empirical equation by using the relationship between the influent COD to $NH_4\;^+-N$ ratio (C/N, -), media concentration (Cm, g/L), influent ammonia nitrogen concentration (Ni, mg/L), effluent ammonia nitrogen concentration (Ne, mg/L), bed expansion rate $(E,\;\%)$, and influent flowrate $(Q,\;m^3/hr)$. The empirical equation from this study is $$V_2\;=\;10^{3.1279}\;C/N^{3.5461}\;C_m\;^{-3.7473}\;N_i\;^{4.6477}\;E^{0.0326}\;N_e\;^{-0..8849}\;Q\;(Two\;Phase\;FB) V_3\;=\;10^{11.7507}\;C/N^{-1.2330}\;C_m\;^{-6.5715}\;N_i\;^{1.5091}\;N_e\;^{-1.8489}\;Q (Three\;Phase\;FB)$$

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.48-58
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• 2003

To obtain the preliminary design data for combustion of paper sludges, decomposition characteristics and combustion kinetics of paper sludges reactor have been determined in a TGA reactor. Also, the combustion characteristics of paper sludges have been determined in a fluidized bed reactor. The data obtained from the TGA reactor indicate that dewatering of paper sludge is terminated at temperature below 130${\circ}$C. With heating rate of 20${\circ}$C/min, combustion is terminated at temperature below 340${\circ}$C .The combustion rate is found to be first order with respect to temperature and oxygen concentration. Activation energies for paper wastes are found to be 570, 700, 2600, 4600 Kcal/mole, respectively. The calcination conversions were investigated with the operating temperature and residence time. In this investigation, it was found that calcination conversion was affected by the operating temperature and residence time. The optimum conditions of operating temperature and mean residence time were 850${\circ}$C and 6 minutes of respectively.

• Environmental Engineering Research
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• v.25 no.1
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• pp.80-87
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• 2020

Landfill waste decomposition generates a dark effluent named, leachate which is characterized by high organic matter content. To minimize these polluting effects, it becomes necessary to develop an effective landfill leachate treatment process. The objective of this study was to evaluate the performance of an innovative approach based on air stripping, anaerobic digestion (AD) and aerobic activated sludge treatment. A reduction of 80% of ammonia and an increase of carbon to nitrogen ratio to 25 were obtained, which is a suitable ratio for AD. This latter AD was performed in fixed bed reactor with progressive loading rate that reached 2 and 3.2 g COD/L/d for the raw and diluted leachate (1:2), respectively. The anaerobic treatment led to significant removal of chemical oxygen demand (COD) and biogas production, especially for the diluted leachate. The COD removal was of 78% for the raw leachate and a biogas production of 4 L/d with 70% methane content. The use of the diluted leachate led to 81% of COD removal and 7 L/d biogas with 75% methane content. It allowed a removal of 77% COD and more than 97% of the organic compounds present in the initial leachate sample.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.1
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• pp.37-42
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• 1988

For the purpose of cultivating landscape plants, the culture soil of briquet ashes and sludge cakes from urban drainages was used as a bed soil. And Taxus cuspidata, syringa vulgaris, Ligstrum obtusifolia and Buxus microphylla were selected as experimental materials on this soil. The comparison of their growth showed the following results. Each plant showed a slight difference in primary growth and two months after planting, there were notable differences between treated and control plots respectively. Syringa vulgaris shoved the highest growth and the next were Ligstrum obtusifolia and Taxus cuspidata in series. Especially Taxus cuspidata showed the lowest quantity of dry weight compared with other plants, and influenced a little by mean temperature and solar radiation. It is expected to get a high effect in landscape planting by using briquet ashes and sludge cakes.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.83-90
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• 2018

This paper introduces a innovative diamond wire saw cutting technology and its experimental verification that can be utilized for cutting heavy structures. While conventional diamond wire saw cutting technologies such as water cooled cutting method and dry cutting method cause severe environmental problems due to generating massive concrete sludge or dust scattering, the proposed method can eliminate those problems considerably. Through extensive experiments using heavy structure test bed and real bridge pier structure, comprehensive analysis and comparative evaluation about various cutting methods were performed. As a result, the innovative diamond wire saw cutting method could achieve a similar cutting and cooling performance to the water cooled cutting method without generating concrete sludge and it showed an improved cutting and cooling performance to the dry cutting method without dust scattering. Consequently it is confirmed that the suggested cutting technology can be a promising environment-friendly alternative in the field of heavy structure dismantling.

• Advances in environmental research
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• v.9 no.4
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• pp.233-249
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• 2020

To date, there is no central wastewater (WW) treatment plant in Erbil city, Kurdistan region, Iraq. Therefore, raw WW disposes to the environment and sometimes it used directly for irrigation in some areas of Erbil city. Disposal of the untreated WW to the natural environment and using for irrigation it causes problems for the people and the environment. The aims of the current work were to study the characteristics, design of primary and different secondary treatment units and reusing of produced WW. Raw WW samples from Ashty city-Erbil city were collected and analyzed for twenty three quality parameters such as Total Suspended Solids (TSS), total dissolved solids, total volatile and non-volatile solids, total acidity, total alkalinity, total hardness, five-day Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), biodegradability ratio (BOD5/COD), turbidity, etc. Results revealed that some parameters such as BOD5 and TSS were exceeded the standards for disposal of WW. Design and calculations for primary and secondary treatment (biological treatment) processes were presented. Primary treatment units such as screening, grit chamber, and flow equalization tank were designed and detailed calculation were illustrated. While, Conventional Activated Sludge (CAS), Sequencing Batch Reactor (SBR) and Moving Bed Biofilm Reactors (MBBR) were applied for the biological treatment of WW. Results revealed that MBBR was the best and economic technique for the biological treatment of WW. Treated WW is suitable for reusing and there is no restriction on use for irrigation of green areas inside Ashty city campus.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.425-433
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• 2011

In order to obtain optimum pre-treatment methods and improve T-N and T-P removal efficiencies, removal rates of pollutants in small-scale livestock wastewater treatment apparatus with water plant filtration bed or activated sludge tank were investigated. Based on the results from the optimum pre-treatment in small-scale livestock wastewater treatment apparatus, removal efficiencies of pollutants in livestock wastewater treatment plant with water plant filtration and activated sludge beds. The removal rates of COD, SS, T-N, and T-P in effluent were 83, 89, 63 and 87% in small-scale livestock wastewater treatment apparatus with water plant filtration bed, respectively. The removal rates of COD, SS, T-N, and T-P in effluent were 96, 95, 86 and 92% in small-scale livestock wastewater treatment apparatus with activated sludge tank, respectively. For increasing the COD, SS, T-N, and T-P removals in small-scale livestock wastewater treatment apparatus, the water plant filtration and activated sludge beds are recommended. In livestock wastewater treatment plant with water plant filtration ($1^{st}$ treatment) and activated sludge ($2^{nd}$ treatment) beds, the concentrations of COD, SS, T-N, and T-P in effluent were 39, 15, 42 and $1mg\;L^{-1}$, respectively. It was shown that the concentrations of COD, SS, T-N, and T-P met acceptable effluent quality standard for livestock wastewater. Based on the above results, the removal rates of COD, SS, T-N, and T-P in effluent were over 99.8, 99.9, 99.2, and 99.9% in livestock wastewater treatment plant, respectively.