scholarly journals Algal Remediation of Wastewater Produced from Hydrothermally Treated Septage

2019 ◽  
Vol 11 (12) ◽  
pp. 3454 ◽  
Author(s):  
Kyle McGaughy ◽  
Ahmad Abu Hajer ◽  
Edward Drabold ◽  
David Bayless ◽  
M. Toufiq Reza

Hydrothermal carbonization (HTC) is a promising technology to convert wet wastes like septic tank wastes, or septage, to valuable platform chemical, fuels, and materials. However, the byproduct of HTC, process liquid, often contains large amount of nitrogen species (up to 2 g/L of nitrogen), phosphorus, and a variety of organic carbon containing compounds. Therefore, the HTC process liquid is not often treated at wastewater treatment plant. In this study, HTC process liquid was treated with algae as an alternative to commercial wastewater treatment. The HTC process liquid was first diluted and then used to grow Chlorella sp. over a short period of time (15 days). It was found that the algae biomass concentration increased by 644 mg/L over the course of 10 days, and which subsequently removed a majority of the nutrients in the HTC process liquid. Around 600 mg/L of algal biomass was collected in the process liquid at the end of treatment (day 15). Meanwhile, chemical oxygen demand (COD), total phosphorous, total Kheldjal nitrogen, and ammonia were reduced by 70.0, 77.7, 82.2, and 99.0% by fifteen days compared to the untreated wastewater, respectively. This study demonstrates that HTC process liquid can be treated by growing algae creating a potential replacement for expensive synthetic nutrient feeds for algal production.

2017 ◽  
Vol 75 (11) ◽  
pp. 2649-2658 ◽  
Author(s):  
Andrzej Jucherski ◽  
Maria Nastawny ◽  
Andrzej Walczowski ◽  
Krzysztof Jóźwiakowski ◽  
Magdalena Gajewska

The aim of the present study was to assess the technological reliability of a domestic hybrid wastewater treatment installation consisting of a classic three-chambered (volume 6 m3) septic tank, a vertical flow trickling bed filled with granules of a calcinated clay material (KERAMZYT), a special wetland bed constructed on a slope, and a permeable pond used as a receiver. The test treatment plant was located at a mountain eco-tourist farm on the periphery of the spa municipality of Krynica-Zdrój, Poland. The plant's operational reliability in reducing the concentration of organic matter, measured as biochemical oxygen demand (BOD5) and chemical oxygen demand (COD), was 100% when modelled by both the Weibull and the lognormal distributions. The respective reliability values for total nitrogen removal were 76.8% and 77.0%, total suspended solids – 99.5% and 92.6%, and PO4-P – 98.2% and 95.2%, with the differences being negligible. The installation was characterized by a very high level of technological reliability when compared with other solutions of this type. The Weibull method employed for statistical evaluation of technological reliability can also be used for comparison purposes. From the ecological perspective, the facility presented in the study has proven to be an effective tool for protecting local aquifer areas.


2012 ◽  
Vol 66 (10) ◽  
pp. 2131-2137 ◽  
Author(s):  
André Luis de Sá Salomão ◽  
Marcia Marques ◽  
Raul Gonçalves Severo ◽  
Odir Clécio da Cruz Roque

There is a worldwide demand for decentralized wastewater treatment options. An on-site engineered ecosystem (EE) treatment plant was designed with a multistage approach for small wastewater generators in tropical areas. The array of treatment units included a septic tank, a submersed aerated filter, and a secondary decanter followed by three vegetated tanks containing aquatic macrophytes intercalated with one tank of algae. During 11 months of operation with a flow rate of 52 L h−1, the system removed on average 93.2% and 92.9% of the chemical oxygen demand (COD) and volatile suspended solids (VSS) reaching final concentrations of 36.3 ± 12.7 and 13.7 ± 4.2 mg L−1, respectively. Regarding ammonia-N (NH4-N) and total phosphorus (TP), the system removed on average 69.8% and 54.5% with final concentrations of 18.8 ± 9.3 and 14.0 ± 2.5 mg L−1, respectively. The tanks with algae and macrophytes together contributed to the overall nutrient removal with 33.6% for NH4-N and 26.4% for TP. The final concentrations for all parameters except TP met the discharge threshold limits established by Brazilian and EU legislation. The EE was considered appropriate for the purpose for which it was created.


2019 ◽  
Vol 10 (2) ◽  
pp. 121
Author(s):  
Cássio Rodrigo Dias Gomes ◽  
Éverton Hansen

No Brasil, apenas uma pequena parcela do esgoto gerado pelas cidades é devidamente tratado em estações de tratamento de efluentes . O uso de soluções individuais (fossa séptica e sumidouro) é empregado em parte do esgoto gerado, e aproximadamente um terço do esgoto doméstico não possui coleta, tampouco tratamento. O presente estudo foi desenvolvido no município de Dois Irmãos, no Rio Grande do Sul. O município avaliado encontra-se em crescimento, com a implantação prevista de novos condomínios residenciais. Desta forma, o uso de estações compactas para o tratamento de efluentes líquidos foi avaliado, verificando sua eficiência e viabilidade econômica, em comparação com a tecnologia de fossa séptica e filtro anaeróbio coletivos, convencionalmente utilizada pelo município (estação de tratamento convencional). O trabalho mostra de forma comparativa, os custos de implantação, operação e manutenção, além de trazer as informações sobre a eficiência dos sistemas de tratamento de efluentes, quais sejam estação de tratamento compacta e estação de tratamento convencional. A questão mais relevante quando se compara os dois sistemas é a diferença no custo de implantação, onde o sistema compacto analisado seria até 81,22% mais econômico do que o convencional. Além da questão econômica, a eficiência do sistema compacto mostra-se superior ao sistema convencional. A estação compacta apresentou 97,97% de remoção de demanda bioquímica de oxigênio, enquanto a estação convencional removeu 77,67% do mesmo parâmetro. Palavras-chave: Estação de Tratamento de Efluente. ETE Compacta. ETE Convencional.ABSTRACTIn Brazil, only a small portion of the sewage generated by the cities is properly treated in wastewater treatment plants. The use of individual solutions (septic tank and sump) is used in part of the generated sewage, and approximately one-third of the domestic sewage has no collection or treatment. The present study was developed in the city of Dois Irmãos, Rio Grande do Sul. The evaluated municipality is growing, with the expected implementation of new residential condominiums. Thus, the use of compact stations for the treatment of liquid effluents was evaluated, verifying their efficiency and economic viability, in comparison with the technology of collective septic tank and anaerobic filter, conventionally used by the municipality (conventional treatment station). The work compares the implementation, operation and maintenance costs, as well as information on the efficiency of wastewater treatment systems (compact treatment plant and conventional treatment plant). The most relevant issue when comparing the two systems is the difference in deployment cost, where the compact system analyzed would be up to 81.22% more economical than the conventional one. Besides the economic issue, the efficiency of the compact system is superior to the conventional system. The compact station showed 97.97% of biochemical oxygen demand removal, while the conventional station removed 77.67% of the same parameter.Keywords: Effluent Treatment Station. Compact STE. Conventional STE.


2008 ◽  
Vol 57 (8) ◽  
pp. 1287-1293 ◽  
Author(s):  
A. Jobbágy ◽  
G. M. Tardy ◽  
Gy. Palkó ◽  
A. Benáková ◽  
O. Krhutková ◽  
...  

The purpose of the experiments was to increase the rate of activated sludge denitrification in the combined biological treatment system of the Southpest Wastewater Treatment Plant in order to gain savings in cost and energy and improve process efficiency. Initial profile measurements revealed excess denitrification capacity of the preclarified wastewater. As a consequence, flow of nitrification filter effluent recirculated to the anoxic activated sludge basins was increased from 23,000 m3 d−1 to 42,288 m3 d−1 at an average preclarified influent flow of 64,843 m3 d−1, Both simulation studies and microbiological investigations suggested that activated sludge nitrification, achieved despite the low SRT (2–3 days), was initiated by the backseeding from the nitrification filters and facilitated by the decreased oxygen demand of the influent organics used for denitrification. With the improved activated sludge denitrification, methanol demand could be decreased to about half of the initial value. With the increased efficiency of the activated sludge pre-denitrification, plant effluent COD levels decreased from 40–70 mg l−1 to < 30–45 mg l−1 due to the decreased likelihood of methanol overdosing in the denitrification filter


2012 ◽  
Vol 7 (1) ◽  
Author(s):  
S. S. Fatima ◽  
S. Jamal Khan

In this study, the performance of wastewater treatment plant located at sector I-9 Islamabad, Pakistan, was evaluated. This full scale domestic wastewater treatment plant is based on conventional activated sludge process. The parameters which were monitored regularly included total suspended solids (TSS), mixed liquor suspended solids (MLSS), mixed liquor volatile suspended solids (MLVSS), biological oxygen demand (BOD), and chemical oxygen demand (COD). It was found that the biological degradation efficiency of the plant was below the desired levels in terms of COD and BOD. Also the plant operators were not maintaining consistent sludge retention time (SRT). Abrupt discharge of MLSS through the Surplus Activated sludge (SAS) pump was the main reason for the low MLSS in the aeration tank and consequently low treatment performance. In this study the SRT was optimized based on desired MLSS concentration between 3,000–3,500 mg/L and required performance in terms of BOD, COD and TSS. This study revealed that SRT is a very important operational parameter and its knowledge and correct implementation by the plant operators should be mandatory.


2017 ◽  
Vol 77 (1) ◽  
pp. 70-78 ◽  
Author(s):  
Yanjun Mao ◽  
Xie Quan ◽  
Huimin Zhao ◽  
Yaobin Zhang ◽  
Shuo Chen ◽  
...  

Abstract The activated sludge (AS) process is widely applied in dyestuff wastewater treatment plants (WWTPs); however, the nitrogen removal efficiency is relatively low and the effluent does not meet the indirect discharge standards before being discharged into the industrial park's WWTP. Hence it is necessary to upgrade the WWTP with more advanced technologies. Moving bed biofilm processes with suspended carriers in an aerobic tank are promising methods due to enhanced nitrification and denitrification. Herein, a pilot-scale integrated free-floating biofilm and activated sludge (IFFAS) process was employed to investigate the feasibility of enhancing nitrogen removal efficiency at different hydraulic retention times (HRTs). The results showed that the effluent chemical oxygen demand (COD), ammonium nitrate (NH4+-N) and total nitrogen (TN) concentrations of the IFFAS process were significantly lower than those of the AS process, and could meet the indirect discharge standards. PCR-DGGE and FISH results indicated that more nitrifiers and denitrifiers co-existed in the IFFAS system, promoting simultaneous nitrification and denitrification. Based on the pilot results, the IFFAS process was used to upgrade the full-scale AS process, and the effluent COD, NH4+-N and TN of the IFFAS process were 91–291 mg/L, 10.6–28.7 mg/L and 18.9–48.6 mg/L, stably meeting the indirect discharge standards and demonstrating the advantages of IFFAS in dyestuff wastewater treatment.


2021 ◽  
Vol 221 ◽  
pp. 31-40
Author(s):  
A.S. Mubarak ◽  
Parvaneh Esmaili ◽  
Z.S. Ameen ◽  
R.A. Abdulkadir ◽  
M.S. Gaya ◽  
...  

2017 ◽  
Vol 12 (2) ◽  
pp. 95 ◽  
Author(s):  
Rachman Syah ◽  
Mat Fahrur ◽  
Hidayat Suryanto Suwoyo ◽  
Makmur Makmur

Pengolahan air buangan tambak superintensif (TSI) adalah usaha untuk mengurangi beban bahan pencemar yang terkandung di dalam air buangan TSI sehingga aman dan tidak membahayakan saat dibuang ke lingkungan. Penelitian ini bertujuan untuk mengevaluasi desain dan performansi Instalasi Pengolahan Air Limbah (IPAL) dalam memperbaiki kualitas air buangan TSI sebelum dibuang ke badan air. IPAL terdiri atas kolam sedimentasi, dua kolam aerasi, dan satu kolam penampungan. Ke dalam kolam penampungan ditebari ikan mujair serta rumput laut Gracilaria sp. yang dibudidayakan dengan metode long line, berfungsi sebagai biokontrol. Sampel air diambil di bagian inlet IPAL, oulet kolam sedimentasi atau inlet kolam aerasi-1, outlet kolam aerasi-1 atau inlet kolam aerasi-2, outlet kolam aerasi-2 atau inlet kolam penampungan, serta outlet kolam penampungan, setiap dua minggu selama 105 hari pemeliharaan. Parameter yang diukur adalah total padatan tersuspensi (TSS), total amonia nitrogen (TAN), nitrit, nitrat, fosfat, bahan organik terlarut (BOT), dan biological oxygen demand (BOD-5). Spesifikasi teknis IPAL yang diamati meliputi ukuran dan volume IPAL, volume dan waktu tinggal air buangan tambak, dan efisiensi kinerja IPAL, serta rasio volume IPAL dan volume total air tambak. Hasil penelitian menunjukkan bahwa IPAL dapat mengurangi beban bahan pencemar dengan tingkat efisiensi antara 53,1%-99,4%; namun masih diperlukan peningkatan kapasitas dalam mengurangi konsentrasi BOT. IPAL menghasilkan efisiensi yang tinggi terhadap TSS, TAN, nitrit, Total Nitrogen (TN), dan fosfat. Rasio volume IPAL dan volume air tambak 30:70 dengan waktu tinggal minimal lima hari, dapat dijadikan acuan dalam pembangunan IPAL tambak superintensif.A wastewater treatment plant (WTP) in a super-intensive shrimp farm is used to reduce organic matters contained in super-intensive shrimp farm effluent. Through the WTP, the waste water from shrimp facilities can safely and harmlessly be released to the receiving environments. The aims of this study were to evaluate the design and performance of a WTP in reconditioning waste water released from a super-intensive shrimp farm prior to release to water bodies. The WTP was made of a series of sedimentation pond, two aeration ponds, and one reservoir or equalitation pond. The tilapia fish and seaweed, Gracilaria sp., were stocked in the equalitation pond where the seaweed was cultured using long line method; these organisms were used as bio-control. Water samples were collected fortnightly during 105 days of culturing duration from the WTP inlet, outlet of sedimentation pond or at inlet of the first aeration pond; outlet of the first aeration pond or inlet of the second aeration pond, outlet of the second aeration pond or inlet of equalitation pond and the outlet of equalitation pond. The measured variables were total suspended solid (TSS), total ammonia nitrogen (TAN), nitrite, nitrate, phosphate, total organic matters (TOM), and five days biological oxygen demand (BOD5). The evaluated technical performances of the plant were its size and volume; volume and retention time of effluent, efficiency of WTP performance and volume ratios of the WTP and total volume of shrimp pond. The results of the study indicated that the WTP was able to reduce concentrations of nutrients and solids in effluent by 53.1%-99.4% of efficiency. However, its capacity need to be increased due to reducing concentrations of TOM. The WTP was highly efficient in reducing the concentrations of TSS, TAN, nitrite, total N, and phosphate. The volume ratios between the plant and pond waters were 30:70 with minimum retention time five which days could be proposed for wastewater treatment pond for super-intensive shrimp ponds.


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