Petrol ürünleri kaynaklı endüstriyel kazaların etki alanı modellemesi
Impact area modelling of industrial accidents caused by petroleum products
Yazar: DERYA KORAŞ
Danışman: PROF. DR. DİDEM SALOĞLU DERTLİ
İstanbul Teknik Üniversitesi / Lisansüstü Eğitim Enstitüsü / Afet ve Acil Durum Ana Bilim Dalı / Afet Yönetimi Bilim Dalı
Derece: Yüksek Lisans, 2024
Konu: Kazalar = Accidents ; Kimya Mühendisliği = Chemical Engineering
Dizin: Acil durum yönetimi = Emergency management

Özet:
Endüstriyel tesisler, çeşitli sektörlerde hammadde ve bileşenlerin işlenmesi, üretimi ve depolanması için malzeme, ekipman ve işgücü gibi kaynakların organize edilerek faaliyetlerin gerçekleştirildiği fiziksel mekanlardır. Çeşitli kimyasallar ile işlem yapılan bu işletmelerde, beklenmedik toksik, reaktif veya yanıcı sıvı ve gaz salınımları sonucunda ortaya istenmeyen sonuçlar çıkabilmekte ve bu olaylar canlılarda ve çevrede beklenmedik etkilerin ortaya çıkmasına neden olabilmektedir. 
İtalya'nın Seveso kasabasında gerçekleşen endüstriyel kaza sonrasında, endüstriyel kazaların oluşmasının engellenmesi ve gerekli önlemlerin alınması amacıyla hazırlanmış olan Seveso Direktifi kabul edilmiştir. Önce Bhopal'de ve Mexico City'de, sonrasında da Enschede, Baia ve Toulouse'daki yaşanan kazalar direktifin tekrardan gözden geçirilmesi gerekliliğini ortaya koymuş ve AB, SEVESO II'nin kapsamını genişleterek direktifi 16 Aralık 2003 tarihinde yayımlamış ve bu direktif ile tehlikeli maddeler içeren büyük endüstriyel kazaların önlenmesine yönelik çeşitli kontrol yükümlülükleri getirmiştir.
Seveso-II Direktifinin ülkemiz mevzuatına uyumlaştıran "Büyük Endüstriyel Kazaların Önlenmesi ve Etkilerinin Azaltılması Hakkında Yönetmelik (BEKRA)" Çevre, Şehircilik ve İklim Değişikliği Bakanlığı ile Çalışma ve Sosyal Güvenlik Bakanlığı'nca oluşturulan bir komisyon hazırlanarak, 30 Aralık 2013 tarihinde Resmî Gazete'de yayımlanarak yürürlüğe girmiştir. Büyük endüstriyel kazaların önlenmesi, önlenemediği durumlarda da etkilerinin azaltılarak, canlı ve çevre için olası bir kazada kayıpların önüne geçilmesinde önemli bir adımdır.
Endüstriyel kazalarda olası yangın, patlama ve toksik yayılım alanlarını hesaplayabilmek için kantitatif kaza modelleri bulunmaktadır. Kazanın olası sonuçları, kazanın öznesi olan kimyasal maddenin cinsi ve miktarı, olay ve ortamın fiziksel koşullarına göre farklı davranan yangın, patlama ve dağılım modelleri kullanarak mesafe ve zamana bağlı olarak nicel olarak tahmin edilebilmektedir. Buna yönelik karmaşık model ve yöntemler içeren çeşitli yazılımlar, Türkiye menşeli AFAD-EKA, Hollanda menşeli TNO EFFECTS yazılımı, Norveç menşeli PHAST yazılımı, ABD menşeli ALOHA yazılımı, AB menşeli ADAM yazılımı vb., mevcuttur.
Sunulan tezde, EFFECTS yazılımı ile gerçek veriler kullanılarak, petrol ürünleri ve türevlerini tesisinde bulunduran ve BEKRA sistemine kayıtlı alt ve üst seviyeli endüstriyel tesisin kaza sonucu ortaya çıkan yangın ve patlama etki alanı modellemeleri çalışılmıştır. Ortam şartları değiştirilerek, kaza olasılığı hesaba katılmadan, tankın keskin kenarından yırtılma sonucu ortaya çıkan endüstriyel kaza sonucu oluşan jet yangın modeli, genleşen buhar patlaması sonucu ortaya çıkan ateş topu modeli, kimyasal maddenin kaynak etrafında havuzlanması sonrasında meydana gelen havuz yangını modeli, buhar bulutu patlama modeli incelenmiştir.

Abstract:
Industrial facilities are physical locations where resources such as materials, equipment, and labor are organized to carry out activities for the processing, production, and storage of raw materials and components in various sectors. In these facilities, where various chemicals are processed, unexpected releases of toxic, reactive, or flammable liquids and gases can occur, resulting in undesirable consequences. These events can lead to unexpected effects on living organisms and the environment.
The Seveso Directive was adopted in the aftermath of an industrial accident in the Italian town of Seveso, with the aim of preventing industrial accidents and taking necessary measures. Accidents that occurred first in Bhopal and Mexico City, and then in Enschede, Baia, and Toulouse, highlighted the need to revise the directive, and the EU published the directive on December 16, 2003, expanding the scope of SEVESO II and introducing various control obligations to prevent major industrial accidents involving dangerous substances.
The Regulation on the Prevention of Major Industrial Accidents and the Reduction of Their Effects (BEKRA), which harmonizes the Seveso-II Directive with Turkish legislation, was prepared by a commission established by the Ministry of Environment, Urbanization and Climate Change and the Ministry of Labor and Social Security, and was published in the Official Gazette on December 30, 2013, and entered into force. The prevention of major industrial accidents and the reduction of their effects in the event that they cannot be prevented is an important step in preventing losses for living beings and the environment in the event of a possible accident.
Quantitative accident models are available to calculate potential fire, explosion, and toxic dispersion areas in industrial accidents. The potential consequences of an accident can be quantitatively estimated as a function of distance and time using fire, explosion, and dispersion models that behave differently depending on the type and quantity of the chemical involved in the accident, the event and environmental conditions. Various software programs containing complex models and methods are available for this purpose, including Turkey-based AFAD-EKA, Netherlands-based TNO EFFECTS software, Norway-based PHAST software, US-based ALOHA software, EU-based ADAM software,
By changing the environmental conditions and without taking into account the probability of an accident, the following models were examined:
• Jet fire model resulting from an industrial accident caused by tearing from the sharp edge of the tank,
• Fireball model resulting from a deflagration to vapor explosion,
• Pool fire model resulting from the pooling of the chemical substance around the source,
• Vapor cloud explosion model.
Heat radiation and lethal effect field modeling are described for the accident scenario that may occur as a result of the spread of liquefied gas as a result of a 5 cm sharp-edged puncture of a tank containing kerosene, diesel, and LPG in the lower and upper level facility. In the modeling, the wind direction is assumed to be 90o to the right. If the tank (equipment) is considered as the accident center, according to the results obtained;
In this study for the lower level facility registered to the BEKRA system, for the results of the Diesel tank, the pool fire area will reach an area of 1550 m2 and a maximum distance of 21 m from the center, and the flare area will reach an area of 1650 m2 and a maximum distance of 38 m from the center. 
The largest impact area with heat radiation (kW/m2) 12700-1000 will be 41000 m2 with a radius of 114 m and a maximum distance of 120 m from the center. The 1% lethality contour, where the lethality area is the highest, will extend over an area of 4950 m2 and up to 45 m from the center. In an area of 2800 square meters, the probability of 1-0.70, which is the highest probability of lethality in the open air, will extend up to 30 m from the center. 
In the distance dependent graphs, the concentration is highest at 0 distance from the Diesel explosion point and the concentration decreases more slowly after 30 m. As the distance from the explosion point decreased, the concentration decreased depending on the distance. Heat radiation remained constant in the first 25 m, but decreased significantly after 40 m and approached zero.
As a result of these events, 1st degree, 2nd degree and 3rd degree burns were experienced, and people in the first 37 m are at 100% risk for 1st degree burns, and in 25 m they are at 100% risk for 2nd degree and 3rd degree burns. The exposure to heat radiation according to the degree of burns is 110 kw/m2 , which is higher than the 1st degree burn area at the distances where 2nd degree and 3rd degree burns will occur.
In the results of the LPG tank in the study for the upper level facility, overpressure area, jet fire area, explosion effect area, flammable area and low level flammable area were formed. 1% fatal effect area will be effective in an area of 292000 m2 with a maximum distance of 440 m from the center and 1% fatal contour will be effective in an area of 726000 m2 with a maximum distance of 1335 m from the center. The overpressure area will be effective on an area of 3400000 m2 and a maximum distance of 437 m from the center.
The lethality probability of LPG in the open air decreases from indoors to outdoors. For the area with the highest probability of 1-0.7, the impact area will affect an area of 120000 m2 up to a maximum distance of 320 m from the center. In the heat radiation scale modeling, for the blue area with the largest area of influence, it will affect an area of 2400000 m2 at a maximum distance of 990 m from the center. 
Another area modeled in the study is the heat radiation scale area. Heat radiation scales are generally divided into three degrees. For the red area, where the heat radiation is the highest, it will be effective in an area of 98000 m2, at a maximum distance of 270 m from the center point. For the green area, it will be effective in an area of 520000 m2 and a maximum distance of 570 m from the center point, and for the blue area with the lowest scale, it will be effective in an area of 2400000 m2 and a maximum distance of 990 m from the center point. 
In the graphs created for LPG depending on the distance, the concentration at 0 distance from the explosion point is the highest at 2400000 mg/m3. The concentration of the gas, which spreads with the wind, reached the breaking point between 0-200 meters and showed a rapid decrease. After 200 m, the decrease in concentration due to distance is slower and after 1700 m it approaches zero point. 
The accumulated gas mass around the tank resulted in a sudden fire and a linear decrease in heat radiation. At 0 distance the heat radiation was the highest and at 0-25 m the heat radiation remained constant. Between 200-700 m there was a parabolic decrease and after 550 m the concentration approached zero.
In these impact areas, 1st degree, 2nd degree and 3rd degree burns were experienced, and 1st degree burns are expected to occur in people between 0-385 m. In areas more than 600 m away, the occurrence of 1st degree burns is outside the impact area. 2nd degree burns will occur in the range of 0-300 m and will lose their effect in areas farther than 450 m For 3rd degree burns, the results will be seen in the range of 0-275 m and no effect will be seen in areas beyond 350 m.
In the heat radiation effect areas depending on the burn degrees and distance, 100%, 50% and 0% rates were examined and according to the 100% rate, 37.5 kW/m2 heat radiation exposure will be experienced at 385 meters with 1st degree burns, 31.5 kW/m2 at 300 m with 2nd degree burns, and 38.5 kW/m2 at 275 m with 3rd degree burns.
According to the results, liquid vapor concentrations and heat radiations are high at distance 0 and decrease with distance as you move away from the accident center. In terms of burn degrees depending on the distance, it is predicted that 3rd degree (lethal burns) will be experienced at the accident center and 1st and 2nd degree burns will be experienced as it moves away from the accident center.