The Slag Regime of Equipment Used for the Secondary Treatment of Steel and the Durability of Its Refractories

2015 ◽  
Vol 56 (4) ◽  
pp. 327-332
Author(s):  
O. Yu. Sheshukov ◽  
I. V. Nekrasov ◽  
M. A. Mikheenkov ◽  
D. K. Egiazar’yan ◽  
L. A. Ovchinnikova ◽  
...  
2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Nusa Idaman Said ◽  
Ikbal Ikbal ◽  
Satmoko Yudo

Sejalan dengan pertumbuhan penduduk yang sangat pesat dan meningkatnya pencemaran air tanah maupun air permukaan, serta distribusi sumber air untuk konsumsi pemakaian air yang tidak merata telah menyebabkan ketidak-seimbangan antara  pasokan dan kebutuhan akan air. Oleh karena itu, menjadi perhatian yang penting dalam melakukan upaya-upaya dalam hal penyediaan sumber air. Salah satu alternatif yang banyak mendapat perhatian di banyak negara di dunia adalah menggunakan teknologi daur ulang air limbah sebagai sumber air baku untuk penyediaan air bersih. Industri migas merupakan salah satu industri yang mempunyai kebutuhan akan air bersih yang besar, khususnya kilang minyak. Pemakaian air di kilang minyak tersebut cukup besar yaitu sebesar 1.400 m3 perjam, apabila air hasil buangannya dapat di daur ulang sebesar 10% atau lebih saja maka kebutuhan air bersih akan dapat dihemat. Tujuan dari kegiatan ini adalah melakukan desain instalasi daur ulang air di suatu kilang minyak. Konsep yang umum dari daur ulang adalah melakukan pengolahan air limbah untuk dijadikan air bersih, dengan menggunakan kombinasi proses pra-pengolahan (preliminary treatment), pengolahan primer (primary treatment), pengolahan primer lanjutan (advanced primary treatment), pengolahan sekunder (secondary treatment), dan pengolahan tersier (tertiary/advanced treatment). Dengan kombinasi proses tersebut dapat mengolah air limbah sampai menghasilkan air olahan dengan kualitas sebagai air minum.  Hasil dari kegiatan ini adalah diperolehnya desain pilot plant instalasi daur ulang air limbah di industri migas dengan kapasitas  9 m3/jam. Kata kunci: pencemaran air, air limbah, desain daur ulang air, kilang minyak


1988 ◽  
Vol 23 (4) ◽  
pp. 568-577
Author(s):  
Harold S. Bailey

Abstract The water quality of the upper 110 kilometres of the St. Croix River is considered to be pristine. A major industrial discharge renders the lower 14 kilometres of the river a water quality limited segment. Prior to 1970 the Georgia-Pacific Pulp and Paper Mill at Woodland, Maine, discharged untreated effluent directly into the river causing dissolved oxygen concentrations to drop well below 5 mg/L, the objective chosen in the interest of restoring endemic fish populations. Since 1972, the Mill has installed primary and secondary treatment, regulated river discharge rate and effluent composition which has greatly improved the summer dissolved oxygen regime. By 1980, dissolved oxygen concentrations were generally above 5.0 mg/L and restocking the river with Atlantic Salmon (Salmo salar) was initiated.


1982 ◽  
Vol 14 (6-7) ◽  
pp. 429-442
Author(s):  
I L Bogert

A one-year experimental program conducted at Edgewater, New Jersey, U.S.A. evaluated the concept of providing secondary treatment by the installation of rotating biological contactors (RBC's) in modified primary sedimentation tanks. A primary tank was divided horizontally into two zones separated by an intermediate floor. Four RBC's were placed in the upper zone. The lower zone provided secondary sedimentation. High rate primary sedimentation was provided to remove grit and trash without removing substantial portions of BOD and SS. The experimental program funded by the U.S. EPA and the Borough of Edgewater was conducted over a full year at different loads. The system proved to be an effective secondary treatment process with little difference in treatment efficiency between summer and winter conditions.


1994 ◽  
Vol 29 (12) ◽  
pp. 31-40 ◽  
Author(s):  
Pia Prohaska Brinch ◽  
Kim Rindel ◽  
Kathryn Kalb

Due to the introduction of stricter nutrient effluent standards, many existing wastewater treatment plants performing only primary or secondary treatment are about to be upgraded. As the space available at the plants is, however, often limited, processes are required which will accommodate the need for increased treatment capacity without requiring much more space. In the hydrolysis of primary or pre-precipitated sludge direct-degradable organic carbon is produced which can speed up the reaction rate and increase both biological phosphorus and nitrogen removal. Full-scale tests with dosing of hydrolysate for biological P and N removal, respectively, have shown that this is a most viable process. The use of on-line monitoring has improved the process further.


Hydrology ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 77
Author(s):  
Nikolay Makisha

The research revealed in the paper considers the improvement of secondary treatment of wastewater in the aerobic reactor to provide removal of organics and nutrients. There were five types of polymer biofilm carriers taken into account initially; however, two of them were decided not to apply due to technological reasons. The main part of the research was divided into three substages to investigate each type of biofilm carrier. According to the literature review, the optimal efficiency may be reached if the carrier filling ratio is 10 to 30% of reactor volume. On this basis, there were three benches launched at each sub-stage with a corresponding filling ratio of 10, 20, and 30%. The fourth reactor at each sub-stage had no floating carrier to control the experiment. The research of all three types of carriers showed the effect of BOD removal in the range of 95–96% for benches equipped with a floating carrier, which can be considered similar to the control bench with the efficiency of 92%. In the case of ammonia nitrogen, the removal control bench showed only 55% of efficiency, while floating carriers helped to increase the efficiency up to 70–86%. Despite obtaining relatively positive results, the research has to be continued to achieve regulation requirements in treatment quality.


2016 ◽  
Vol 869 ◽  
pp. 765-767 ◽  
Author(s):  
Layane Rodrigues Almeida ◽  
João Sammy Nery Souza ◽  
Edson Cavalcanti Silva Filho ◽  
Josy Anteveli Osajima

The presence of organic pollutants, which cannot be eliminated by conventional processes of primary and secondary treatment, can be problematic. Photocatalytic processes offer an efficient breakdown of organic pollutants into non-toxic compounds such as CO2 and H2O. This paper proposes the use of the titanium dioxide embedded in palygorskite as a photoactive material in the degradation of cationic dye, Coomassie Brilliant Blue. The system was irradiated using UV light for a maximum time of 120 minutes. The concentration of the dye used was 1.0x10-4 mol L-1 in 0.5 g L-1 of the photoactive material. The kinetics of the system was monitored by UV-Vis spectrophotometry. In 120 minutes of radiation, the process of photocatalysis reduced the initial concentration of the Coomassie Brilliant Blue dye in half.


2009 ◽  
Vol 59 (4) ◽  
pp. 779-786 ◽  
Author(s):  
Gopal Chandra Ghosh ◽  
Takashi Okuda ◽  
Naoyuki Yamashita ◽  
Hiroaki Tanaka

The occurrence and elimination of seventeen antibiotics (three macrolides: azithromycin, clarithromycin and roxithromycin; five quinolones: ciprofloxacin, enrofloxacin, levofloxacin, nalidixic acid and norfloxacin; five sulfonamides: sulfadimethoxine, sulfadimizine, sulfamerazine, sulfamethoxazole and sulfamonomethoxine; and others: tetracycline, lincomycin, salinomycin and trimethoprim) were investigated at four full-scale sewage treatment plants in Japan. The highest concentration was recorded for clarithromycin (1,129 to 4,820 ng/L) in influent, followed by azithromycin (160 to 1,347 ng/L), levofloxacin (255 to 587 ng/L) and norfloxacin (155 to 486 ng/L). A vary inconsistence picture was obtained with negative to over 90% removal. Nalidixic acid (53 to100%) exhibited higher removal efficiency followed by norfloxacin (75 to 95%), levofloxacin (40 to 90%), ciprofloxacin (60 to 83%) and enrofloxacin (38 to 74%). Among macrolides, clarithromycin (50 to 88%) and azithromycin (34 to 86%) showed relatively higher removal efficiency than roxithromycin (−32 to 59%). For most of the antibiotics removal efficiency was higher in A2O and AO based secondary treatment process than CAS process. The effect of the antibiotics on bacterial ammonia oxidation determined by oxygen uptake rate presented that there was no significant effect below 0.05 mg/L of each antibiotics. Even at the same concentration, antibiotics in mixed condition had higher inhibition effects than individuals.


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