63 research outputs found
Submarine disposal method of mine tailings (slurry sludge)
Madencilik endüstrisi modern toplumun gelişmesinde rol oynayan en önemli endüstriyel faaliyetlerinden biri olmakla birlikte dünyanın
en büyük atık üreten endüstrisidir. Gelişen teknoloji ve endüstriyel faaliyetlerin ihtiyacı olan hammaddelerin madencilik faaliyetleri
ile doğal kaynaklardan elde edilmesi, biyolojik çeşitliliğin yok edilmesine ve çevre kirliliği sorunlarına neden olabilmektedir.
Madencilik faaliyetlerinden vazgeçilmesi mümkün olmadığına göre, madenlerin çıkartılmasında kamu yararının yanında doğal
kaynakların korunması ve çevre kirliliği oluşturmaması konusunda da daha duyarlı olunmalı ve uygun bertaraf yöntemleri için çeşitli
mühendislik tekniklerinin uygulanması hedeflenmelidir. Madencilik faaliyetleri sonucu oluşan atıklardan olan çamur genel olarak
arazilerde (atık barajlarında veya atık döküm sahalarında) depolanarak bertaraf edilmektedir. Bu depolama alanlarında ise asit
maden drenajı (sülfit oksidasyonundan dolayı), geoteknik stabilite ve diğer bazı sebeplerden dolayı çevresel sorunlar meydana
gelebilmektedir. Yerüstü atık barajları depolama alanlarında oluşan olumsuz nedenlerden dolayı maden atığı çamurların sucul alıcı
ortamlarda bertarafı, özellikle sabit indirgeme koşulları altında ve sülfit minerallerinin jeokimyasal olarak istikrarlı olduğu derin
deniz altlarında bertarafı bir seçenek olarak görülebilir. Bu çalışmada, maden atıklarının ve maden cevheri zenginleştirme
atıklarından olan sulu çamurun (maden atık çamurunun) genel bertaraf yöntemleri, özellikle denizaltına deşarj ve denizaltında
depolama yöntemi incelenmiştir. Bu yöntemin olası olumlu/olumsuz çevresel etkileri tartışılmıştır. Türkiye’de bulunan maden atığı
çamuru derin denizaltı depolama (Karadeniz için) tesisi ve bu deşarjın (yöntemin) etkilerini belirlemek için yapılan deneysel çalışmalar
değerlendirilmiştir. Bu kapsamda yapılan deneysel çalışmalar değerlendirildiğinde, derin deniz deşarjı tesisiyle Karadeniz’e deşarj
edilen maden atık çamurlarının denizin tabanına doğru hareket eden bir atık olduğu (negatif yüzerliliğe sahip veya batan atık), anoksik
bölgeden oksijenli bölgeye yükselemediği belirlenmiştir.The mining industry is one of the most important industrial activities that are playing a role to development of the modern society and
at same time, this industry is the world's largest waste-producing industry. The raw materials, which are needed for the developing
technology and industrial activities, are obtained from naturel sources with the mine activities. These mine activities can lead to
destruction of biological diversity and environmental pollution problems. According to the abandonment of mining activities not
possible, these activities should also be more sensitive to protection of natural sources and prevention of environmental pollution. The
appropriate disposal methods and application of various engineering techniques should be investigated for this purpose. Mine waste
sludge (or slurry sludge) which is produced from ore process generally is disposal in on-land storage facilities. The various
environmental problems can arise due to acid mine drainage (due to sulfite oxidation), geotechnical stability and some other reasons
in on-land storage areas. Due to negative effects of on-land storage facilities on the environment, mine tailings (or mine waste sludge)
disposal in the receiving environments such as submarine, under constant reduction conditions and geochemically stable sulphite
minerals, can see as a new and safer alternative method to land storage facilities. In this study, general disposal methods (especially
submarine disposal method) were investigated for mine waste sludge or mine tailings that are forming from ore process. Possible
positive and negative environmental effects of this method were discussed. Submarine disposal plant of mine tailings (for the Black
Sea) in Turkey and studies to determine the effects of this discharge were evaluated. According to the results of these experimental
studies, the mine tailings (or mine waste sludge) which is discharged to Black Sea are defined as a negative buoyancy waste because
of it moved to bottom of the sea and could not to reach the strata where living organisms from the anoxic zone
Determination of Radiological Parameters Using Natural Radioactivity Concentrations of Central Anatolia Region Soil Samples
Yatay deşarj edilen soğuk-yoğun atıksuların bazı deşarj parametrelerinin belirlenmesi
Termal
kirlilik, okyanus, göl veya nehir gibi sucul alanlarda ortam sıcaklığının insan
faaliyetleri sonucunda artması veya azalması olarak tanımlanır. Termal
kirliliğe, enerji santralleri, sıvılaştırılmış doğalgaz terminalleri (LNG) ve
endüstriyel tesislerin ısıtma veya soğutma amaçlı kullanılan daha sonra alıcı
ortamlara deşarj edilen suları neden olur. Alıcı ortamlara deşarj edilen termal
atıksuların en önemli kaynaklarından biri LNG gazlaştırma terminallerinden
kaynaklanan soğuk sulardır. Soğuk sular genellikle kıyısal sulara deşarj
edilirler. Bu sular deşarj edildikleri alıcı ortamlara göre yoğunluklarının
yüksek olması nedeniyle bir çeşit negatif yüzen (batan) jetlerdir. Alıcı ortam
canlı türlerine olumsuz etkilerinden dolayı soğuk sular, yüksek seviyede
seyrelme sağlayacak şekilde deşarj edilmelidir. Bu çalışmada, yatay olarak
deşarj edilen soğuk-yoğun suyun birinci seyrelme ve çarpma noktası gibi bazı
deşarj parametreleri laboratuvar ortamında dairesel deşarj portu kullanılarak
belirlenmiştir. Soğuk-yoğun atıksuyun alıcı ortam içerisindeki davranışını (jet
geometrisini) belirlemek için renk maddesi olarak Rhodamin B ilavesi
yapılmıştır. Renklendirilmiş soğuk-yoğun
atıksuyun anlık fotoğraflarını çekmek için yüksek çözünürlüklü kamera ve atıksu
jet merkezinde meydana gelen sıcaklık değişimlerini (seyrelmeler) ölçmek için
de hassas termal problar kullanılmıştır. Farklı atıksu yoğunlukları elde etmek
için -3 °C, -5 °C ve -7 °C gibi üç değişik sıcaklık fark değerleri
uygulanmıştır. Bu çalışmada elde edilen sonuçlara göre soğuk su deşarjlarının
tabana çökme eğilimde olan negatif yüzen (batan) jet gibi davrandığı
belirlenmiştir. Ayrıca bu çalışmada, ortalama normalize edilmiş çarpma noktası
mesafesi ve birinci seyrelmenin 2.333 ve 0.491 olduğu bulunmuştur
REMOVAL OF COPPER FROM INDUSTRIAL WASTEWATER USING MANGANESE FERRITE NANOPARTICLES: EVALUATION OF EQUILIBRIUM AND KINETIC MODEL
In this study, the removal of Cu(II) from real industrial wastewater, being taken from galvanotechnic industry, by means of manganese ferrite (MnFe2O4) nanoparticles (NPs) was investigated. The effects of pH, adsorbent dosage, and contact time on Cu(II) removal from wastewater were monitored using the real wastewater while the effect of initial concentration was studied on synthetic aqueous solutions. Optimal conditions were found for copper removal in this study. Cu(II) removal and adsorption capacity of MnFe2O4 NPs were achieved as 84.25% and 43.02 mg/g, respectively. In addition, other optimum conditions such as pH, adsorbent dosage and contact time were found as 5, 2 g/L and 120 min in this study, respectively. The removal of copper using MnFe2O4 NPs was fitted with Freundlich isotherm and pseudo second-order kinetic models. According to data obtained from desorption studies, MnFe2O4 NPs are regenerable and can be used several times. The results indicated that MnFe2O4 NPs are suitable adsorbents for removing Cu(II) from industrial wastewater
Investigation of horizontal cold water discharge initial dilutions at various temperature differences using duckbill valve
Thermal pollution, that is a temperature change in natural water body, can have adverse effects on the organisms in the aquatic environment as river, lake, or ocean. A common cause of thermal pollution is the use of water as a cooling and heating system by power plants, liquefied natural gas (LNG) regasification terminals, and industrial manufacturers. Cold water discharges into a receiving water body, which are mainly originated from LNG regasification terminals from open cycle heating units, are a kind of thermal effluent. Disposal of cold water with an environmentally protective way can be applied as a dilution method using marine outfall systems. In order to obtain a better dilution in a marine outfall, there is a multiport diffuser at the end of the pipeline. Experimentally performed single port analysis of an outfall is a method of initial dilution investigation for performance determination of designed system. Because of the fact that cold water discharge is denser than receiving ambient water in the marine environment, it is a negatively buoyant dense jet. In this study, horizontally discharged cold water jet initial dilutions at various temperatures were experimentally investigated in a laboratory model using duckbill valve discharge port. Three discharge temperature differences were used as T-0=-3, -5, and -7 degrees C in the laboratory model for determination of the initial dilutions, S, in the cold water jet centerline. Densimetric Froude numbers (F) were calculated as 446.03, 358.43, and 321.76 for the selected temperature differences, respectively. This laboratory model study was also aimed at obtaining some experimental coefficients, such as impingement point distance, as design criteria for horizontally discharged cold water outfalls using duckbill valves
Determination of some discharge parameters of horizontally discharged cold-dense wastewaters
Thermal pollution is defined as increase or decrease in temperature of an aquatic environment which may be ocean, lake or river by human influence. A common cause of thermal pollution is the use of water as a cooling and heating system by power plants, liquefied natural gas (LNG) re-gasification terminals and industrial manufacturers. One of the important sources of thermal effluents is cold water discharges, which are mainly originated from LNG re-gasification terminals from open cycle heating units. Cold water can be frequently discharged into coastal waters. Due to its high density, cold water discharge is a kind of negatively buoyant jet. Because of some undesired effects of cold water on receiving water species, should be discharged properly into the marine environment with a high level of initial dilution. Some discharge parameters of horizontally discharged cold-dense wastewater such as initial dilutions, impingement points were determined in a laboratory system using circular port in this study. To determine the behavior of the cold-dense wastewater (wastewater jet geometry) Rhodamine B as a colorant was added to the wastewater. A high-resolution camera was used to take snapshots of the colored cold-dense wastewater. Temperature changes (dilutions) in the cold-dense wastewater jet centerline were detected with sensitive thermal probes. To gain different densities, three discharge temperature differences were used as -3 degrees C, -5 degrees C and -7 degrees C. According to the results of this study, it was determined that the cold water discharges behaved like a negative buoyant jet. In addition, it was calculated that the averages of the normalized impingement point and initial dilution of the cold water were found 2.333 and 0.491, respectively
Adsorption of Heavy Metals from Industrial Wastewater by Using Polyacrylic Acid Hydrogel
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