High-strength wastewater treatment in a pure oxygen thermophilic process: 11-year operation and monitoring of different plant configurations

2015 ◽  
Vol 71 (4) ◽  
pp. 588-596 ◽  
Author(s):  
M. C. Collivignarelli ◽  
G. Bertanza ◽  
M. Sordi ◽  
R. Pedrazzani

This research was carried out on a full-scale pure oxygen thermophilic plant, operated and monitored throughout a period of 11 years. The plant treats 60,000 t y−1 (year 2013) of high-strength industrial wastewaters deriving mainly from pharmaceuticals and detergents production and landfill leachate. Three different plant configurations were consecutively adopted: (1) biological reactor + final clarifier and sludge recirculation (2002–2005); (2) biological reactor + ultrafiltration: membrane biological reactor (MBR) (2006); and (3) MBR + nanofiltration (since 2007). Progressive plant upgrading yielded a performance improvement chemical oxygen demand (COD) removal efficiency was enhanced by 17% and 12% after the first and second plant modification, respectively. Moreover, COD abatement efficiency exhibited a greater stability, notwithstanding high variability of the influent load. In addition, the following relevant outcomes appeared from the plant monitoring (present configuration): up to 96% removal of nitrate and nitrite, due to denitrification; low-specific biomass production (0.092 kgVSS kgCODremoved−1), and biological treatability of residual COD under mesophilic conditions (BOD5/COD ratio = 0.25–0.50), thus showing the complementarity of the two biological processes.

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Máté Osvald ◽  
Gergely Maróti ◽  
Bernadett Pap ◽  
János Szanyi

Reinjection of heat-depleted thermal water has long been in the center of scientific interest in Hungary regarding around 1000 operating thermal wells. While the physical and chemical aspects of reinjection have partly been answered in the past years, the effects of biological processes are still less known. We carried out our investigations in the surface elements of the Hódmezővásárhely geothermal system which is one of the oldest operating geothermal systems in Hungary. About one-third of the used geothermal water has been reinjected since 1998 by two reinjection wells at the end of the thermal loops. During the operation, plugging of the surface system was experienced within a few-day-long period, due to biological processes. The goal of our research was to find the dominant species of the microbial flora and to make a proposal to avoid further bacterial problems. We found that the reinjected, therefore the produced, water’s chemical oxygen demand, phenol index, and BTEX composition basically determine the appearing flora on the surface. When the concentration of these compounds in the thermal water is significant and residence time is long enough in the buffer tank, certain bacteria can be much more dominant than others, thus able to form a biofilm which plugs the surface equipment much more than it is expected.


2019 ◽  
Vol 17 (1) ◽  
pp. 1288-1300
Author(s):  
Anna Kwiecińska-Mydlak ◽  
Marcin Sajdak ◽  
Katarzyna Rychlewska ◽  
Jan Figa

AbstractCoke oven liquor is one of the most contaminated liquid streams generated by the coal processing industry, thus its proper treatment and utilization is crucial for sustainable and environmentally neutral plant operation. The conventional wastewater treatment process comprises of chemical and biological processes. Within the current research the detailed role of chemical treatment is described. Commercially available iron-based coagulants (PIX100, PIX100COP, PIX113, PIX116) were tested to understand their removal efficiency and impact on the stream parameters. The influence of iron dose in the range of 300-500 mgFe/L on the process performance was also examined.It was found that the main role of chemical treatment was to bind toxicants harmful to activated sludge microorganisms, i.e. free and complex cyanides and sulphides. Among the tested iron-based conventional coagulants ferrous salts were more efficient than ferric salts. It was also observed that efficiency of the process strongly depended on wastewater properties (especially in regard to pH, which should be in the range of 9-10) and the coagulant selection needed to be done individually for a given wastewater type. The removal rates of particular contaminants were diversified and for free cyanides, complex cyanides and sulphides they were in the range of 23-91%, -156-77% and -357-98%, respectively. The expected, simultaneous removal of chemical oxygen demand (COD) during the treatment was not observed and even the parameter value increased after the process due to probable formation of compounds less vulnerable to oxidation.


2018 ◽  
Vol 203 ◽  
pp. 03005
Author(s):  
Idzham Fauzi Mohd Ariff ◽  
Mardhiyah Bakir

A dynamic simulation model was developed, calibrated and validated for a petrochemical plant in Terengganu, Malaysia. Calibration and validation of the model was conducted based on plant monitoring data spanning 3 years resulting in a model accuracy (RMSD) for effluent chemical oxygen demand (COD), ammoniacal nitrogen (NH3-N) and total suspended solids (TSS) of ±11.7 mg/L, ±0.52 mg/L and ± 3.27 mg/L respectively. The simulation model has since been used for troubleshooting during plant upsets, planning of plant turnarounds and developing upgrade options. A case study is presented where the simulation model was used to assist in troubleshooting and rectification of a plant upset where ingress of a surfactant compound resulted in high effluent TSS and COD. The model was successfully used in the incident troubleshooting activities and provided critical insights that assisted the plant operators to quickly respond and bring back the system to normal, stable condition.


2012 ◽  
Vol 8 ◽  
pp. 44-47
Author(s):  
Ghazal Nosheen ◽  
Muhammad Ullah ◽  
Kashif Ahmad Khan ◽  
Attiq Ur Rehman

The disposal of untreated industrial effluent into receiving water courses has become a major environmental challenge being faced by most of the developing countries. The high-strength and toxic wastes are responsible for a variety of water-borne diseases. In Pakistan numerous industrial units that dispose their effluent directly into receiving stream without any treatment. This study was, therefor designed to assess the wastewater characteristics of some major industrial units in the surrounding area of River Kabul, which is one of the most signifi cant resources of water in the north region of the country.The main objectives of this study were to evaluate the wastewater characteristics of some major industrial units in terms of BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), and TSS (Total Suspended Solids) etc. For this purpose, various representative samples were collected from the major industrial units like sugar, paper, ghee (Butter) and textile mills, and were analyzed using standard laboratory techniques. The results indicates that the BOD of sugar, paper, ghee (butter) and textile mills is in the range of 2235mg/L, 1150mg/L, 844mg/L and 745mg/L, respectively. Whereas, the COD of sugar, paper, ghee and textile mills was noticed to be 3945mg/L 2045mg/L, 2240mg/L and 1244mg/L respectively. Owing to the disposal of such highstrength wastes water without treatment, a remarkable increase in the TSS from 96 to 382mg/L, and decrease in DO (Dissolved Oxygen) concentration from 8.8 to 6.7mg/L of River Kabul was observed. The results of this study suggest that all the wastewater coming from the industrial sources should be properly treated as an integral part of their production before their fi nal disposal into River Kabul to secure its natural water quality.DOI: http://dx.doi.org/10.3126/hn.v8i0.4924Hydro Nepal: Journal of Water, Energy and Environment Issue No. 8, 2011 JanuaryPage: 44-47Uploaded date: 23 June, 2011


1991 ◽  
Vol 23 (7-9) ◽  
pp. 1417-1425 ◽  
Author(s):  
Sheng-Kun Chen ◽  
Chin-Kun Juaw ◽  
Sheng-Shung Cheng

Two sets of fixed-film biological processes were operated separately for nitritification of amnonium and for denitritification of nitrite associated with organic compounds. High strength amnonium wastewater (50-1000 mg NH4+-N/l) could be effectively nitritified by a draft-tube fluidized bed which was operated at an extremely high loading of 1.0 kg NH4−1-N/m3.day with 95% amnonium conversion and 60 to 95% nitrite formation. Additionally, a biofilm fixed-bed was employed to denitritify the high strength nitrite (200 to 1000 mg NO2−-N/l) associated with organic compounds of glucose, acetate and benzoic acid. Complete nitrite removal could be achieved with sufficient HRT and COD/NO2−-N ratio. The conversion ratios were estimated experimentally at 2.5 for glucose and acetate, and 2.0 g ∆COD/g ∆NO2−-N for benzoic acid. A proposed process of an aerobic nitritifying biofilm reactor combined with an anoxic denitritifying biofilm reactor in series could be employed for complete nitrogen removal.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Akhil Arora ◽  
M. M. Faruque Hasan

AbstractMedical oxygen concentrators (MOCs) are used for supplying medical grade oxygen to prevent hypoxemia-related complications related to COVID-19, chronic obstructive pulmonary disease (COPD), chronic bronchitis and pneumonia. MOCs often use a technology called pressure swing adsorption (PSA), which relies on nitrogen-selective adsorbents for producing oxygen from ambient air. MOCs are often designed for fixed product specifications, thereby limiting their use in meeting varying product specifications caused by a change in patient’s medical condition or activity. To address this limitation, we design and optimize flexible single-bed MOC systems that are capable of meeting varying product specification requirements. Specifically, we employ a simulation-based optimization framework for optimizing flexible PSA- and pressure vacuum swing adsorption (PVSA)-based MOC systems. Detailed optimization studies are performed to benchmark the performance limits of LiX, LiLSX and 5A zeolite adsorbents. The results indicate that LiLSX outperforms both LiX and 5A, and can produce 90% pure oxygen at 21.7 L/min. Moreover, the LiLSX-based flexible PVSA system can manufacture varying levels of oxygen purity and flow rate in the range 93–95.7% and 1–15 L/min, respectively. The flexible MOC technology paves way for transitioning to an envisioned cyber-physical system with real-time oxygen demand sensing and delivery for improved patient care.


2017 ◽  
Vol 76 (4) ◽  
pp. 813-822 ◽  
Author(s):  
Bismark Dwumfour-Asare ◽  
Philomina Adantey ◽  
Kwabena Biritwum Nyarko ◽  
Eugene Appiah-Effah

Greywater management in Ghana receives little or no attention although untreated greywater is associated with environmental and public health risks. This paper assesses greywater characteristics and handling practices among urban households in three selected communities in Kumasi, the second largest city of Ghana. The study involved in-depth surveys (interviews and observations) with 90 households, and collection of 18 greywater samples from nine greywater sources for laboratory analysis. Average greywater generation is 43.36 ± 17 litres per capita per day, equivalent to 36% of average water consumption. Greywater is untreated before disposal (≈99%), and disposal is mainly (89%) into drains and onto streets. Biochemical oxygen demand (BOD) and chemical oxygen demand (COD) levels are high but give very low BOD/COD ratios (0.20 ± 0.07) indicating a very low biodegradability potential. Nutrient levels are high: 12 times (P) and 30 times (N) in excess of standard discharge limits. Other contaminants detected are heavy metals (Fe, Pb, Zn and Cd), microbes (total coliforms, Escherichia coli and Salmonella spp.), and organic micropollutants – benzalkonium chloride, parabens (methyl and propyl), sodium benzoate and hypochlorite – and details of the levels are discussed in the paper. Greywater reuse could be useful for biomass production, but it also presents a challenge and threat to natural biological processes and water sources.


2013 ◽  
Vol 68 (9) ◽  
pp. 1994-1999 ◽  
Author(s):  
Muhammad Umar ◽  
Felicity Roddick ◽  
Linhua Fan

The UVC/H2O2 process was studied at laboratory scale for the treatment of one moderate (conductivity ∼8 mS/cm) and two high salinity (∼23 mS/cm) municipal wastewater reverse osmosis concentrate (ROC) samples with varying organic and inorganic characteristics. The process efficiency was characterized in terms of reduction of dissolved organic carbon (DOC), chemical oxygen demand (COD), colour and absorbance at 254 nm (A254), and the improvement of biodegradability. The reduction of colour and A254 was significantly greater than for DOC and COD for all samples due to the greater breakdown of humic compounds, as confirmed by fluorescence excitation-emission matrix spectra. Fairly small differences in the reduction of DOC (26–38%) and COD (25–37%) were observed for all samples, suggesting that the salinity of the ROC did not have a significant impact on the UVC/H2O2 treatment under the test conditions. The biodegradability of the treated ROC samples improved markedly (approximately 2-fold) after 60 min UVC/H2O2 treatment. This study indicates the potential of UVC/H2O2 treatment followed by biological processes for treating high-salinity concentrate, and the robustness of the process where the characteristics of the secondary effluent (influent to RO) and thus resultant ROC vary significantly.


2018 ◽  
Vol 77 (7) ◽  
pp. 1899-1908 ◽  
Author(s):  
Güçlü Insel ◽  
Ahmet Karagunduz ◽  
Murat Aksel ◽  
Emine Cokgor ◽  
Gokce Kor-Bicakci ◽  
...  

Abstract In this study, an integrated aerobic membrane bioreactor (MBR)-nanofiltration (NF) system has been applied for advanced treatment of Opium processing wastewaters to comply with strict discharge limits. Aerobic MBR treatment was successfully applied to high strength industrial wastewater. In aerobic MBR treatment, a non-fouling unique slot aeration system was designed using computational fluid dynamics techniques. The MBR was used to separate treated effluent from dispersed and non-settleable biomass. Respirometric modeling using MBR sludge indicated that the biomass exhibited similar kinetic parameters to that of municipal activated sludge systems. Aerobic MBR/NF treatment reduced chemical oxygen demand (COD) from 32,000 down to 2,500 and 130 mg/L, respectively. The MBR system provided complete removal of total inorganic nitrogen; however, nearly 50 mgN/L organic nitrogen remained in the permeate. Post NF treatment after MBR permeate reduced nitrogen below 20 mgN/L, providing nearly total color removal. In addition, a 90% removal in the conductivity parameter was reached with an integrated MBR/NF system. Finally, post NF application to MBR permeate was found not to be practical at higher pH due to low flux (3–4 L/m2/hour) with low recovery rates (30–40%). As the permeate pH lowered to 5.5, 75% of NF recovery was achieved at a flux of 15 L/m2/hour.


Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 726 ◽  
Author(s):  
Kimberly Swain ◽  
Bassim Abbassi ◽  
Chris Kinsley

Significant over-strength discharge fees are often imposed on breweries for the disposal of high-strength effluent to sanitary sewers. In this research work, the removal performances of electrocoagulation (EC) compared with operating electrocoagulation and chemical coagulation in sequence (EC-CC) or vice-versa (CC-EC) was examined to determine the capability of treatment in reducing the strength of the wastewater. Optimal operating parameters regarding electrolysis time, initial pH, and applied power were determined in conjunction with nutrient removal performance, electrode consumption and energy usage. Combined EC-CC treatment has been demonstrated to be economically feasible for brewery wastewater applications from an energy consumption perspective due to the efficiency of nutrient removal and the reduction of sewer discharge costs. Treatment by EC-CC at 5 W for 20 min using aluminum electrodes resulted in enhanced and consistent removal efficiencies of 26%, 74%, 76%, and 85% for chemical oxygen demand (COD), reactive phosphorous (RP), total phosphorous (TP) and total suspended solids (TSS), respectively. Energy consumption was the main contributor to operating cost. By considering potential recovered over-strength discharge fees (ODF), EC-CC treatment is economically feasible and beneficial in a brewery wastewater application. The results demonstrated the effectiveness of the CC-EC process to remove phosphorous, organics and solids from brewery wastewater at lower power supply, so that the recovered ODF cost for CC-EC at 5 W-EC is 23% higher than at 10 W-EC.


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