Ayırımsız nötron aktivasyon analizi sonuçlarını kullanarak geliştirilen hava kirliliği analiz yönteminin İzmir iline uygulanması

Abstract

Ill ÖZET Bu tezde İzmir ilini konu alan bir hava kirliliği analizi sunulmuş tur. Çalışmada alışılagelmiş kirlilik değerlendirmesinden ayrı olarak, elementlerin atmosferdeki davranışları incelenmiştir. Ayrıca kimyasal elementlerle meteorolojik parametreler arasındaki ilişki araştırılmıştır. Çalışmada uygulamanın İzmir ilinde yapılmasının nedeni; İzmir' in Türkiye'nin büyük endüstri ve yerleşim merkezlerinden birisi olması, aynı zamanda bu bölgenin meteorolojik koşullar açısından büyük de ğişiklikler göstermesidir. Kirlilik parametreleri Şubat ve Temmuz 1975 aylarında İzmir'in Konak semtinden alman hava kiri filtrelerinden elde edilmiştir. Çalışmanın birinci bölümünde hava kirliliği tanımlanmıştır. Ayrı ca İzmir ilinin topoğrafik, coğrafik ve endüstriyel özellikleri anlatıl mıştır. İkinci bölümde çalışmada kullanılan kimyasal ve istatistiksel me totlar geniş şekilde anlatılmıştır. Bu bölümde rüzgâr analizinde kulla nılan Lambert metodu verilmiştir. Ayrıca hava kirini toplamada kul lanılan filtreleri değerlendirme yöntemi anlatılmıştır. Bu değerlendir mede kullanılan «Ayırımsız Nötron Aktivasyon Analizi» (N. N. A. A.) detaylı bir şekilde açıklanmıştır. Çalışmanın üçüncü bölümünde İzmir'in hava kirliliği kriteri araş tırılmıştır. Araştırma zenginleşme faktörü metodu ile yapılmıştır. Bu metotla yapılan araştırmada İzmir'de kış periyodunda Cl, V, Cr, Zn, As, Se, Br, Sb, I ve Cs elementlerinin zenginleşme faktörleri büyük bu lunmuştur. Bu bölümde ayrıca İzmir havası, temiz kabul edilen Türki ye'de Van, Dünya'da Twin Georges ve Jungfraujoch merkezlerinin ha vaları ile karşılaştırılmıştır. sonuçda İzmir havasının kirli olduğu gö rülmüştür.IV Dördüncü bölümde, rüzgâr yönü ve şiddeti, bağılnem ve sıcaklıkla kirleticilerin taşınımı ve miktarlarındaki değişimleri araştırılmıştır. Çalışmanın beşinci bölümünde İzmir havasındaki eser elementlerin ve katı parçacıkların (T. S. P.) günlük konsantrasyonlarının dağılımı gözönüne alınarak gruplandırma yapılmıştır. Son bölümde ise elde edilen sonuçlar verilmiştir.

V SUMMARY APPLICATION OF AN AIR POLLUTION ANALYSIS METHOD DEVELOPED BASED ON THE RESULTS OF THE NON-DESTRUCTIVE NEUTRON ACTIVATION ANALYSIS TO THE PROVINCE OF IZMIR. This thesis deals with an air pollution analysis applied to the pro vince of İzmir. Unlike the usual pollution evaluation, the present study is focused on the behavior of elements in the atmosphere. In addition, the rela tion between the chemical elements and the meteorological parameters is studied. İzmir is selected as an interesting and suitable province for applying this analysis on the grounds that it is one of the largest industrial and residential centers in Turkey and it exhibits large vari ations in meteorological conditions. Air pollution parameters have been obtained from the filtered dirt data collected in the Konak district of İzmir during the months ot February and July 1975. The first chapter of the thesis presents a general introduction to the study of air pollution. Pollutans and pollutant sources are briefly classified and general information is given on the air pollution aspects of the atmosphere. This chapter is concluded with a description of topographical, geographical and industrial features of the province of İzmir.VI The second chapter is devoted to the methods used in the study. First a wind analysis is presented. It is noted that the State Meteorolo gical Office determines the mean wind velocity by using two different methods. In the first method the velocity readings taken by local sta tions daily at 7.00, 14.00 and 21.00 are directly averaged out. In the second method the mean velocity is calculated by dividing the sum of velocities to the total frequency. On the other hand, the method used in thepresent work is based upon the Lambert formula that provides an accurate assessment of the dominant wind direction as well as the ave rage speed. The second chapter continues with a presentation of the techniques used to evaluate the pollutants collected in filters. The Non-destructive Neutron Activation Analysis method used to conduct quantitative and qualitative analysis of the chemical elements contained in the pollu tants is described in detail. The third chapter presents the details of the air pollution criterion established in this thesis for the province of Izmir. One of the methods to evaluate air pollution is the method of Enrichment Factor. This met hod is briefly described and a procedure is established to use it to deter mine the air pollution criterion in Izmir. The Enrichment Factor is given by the expression C C X(Air) Al(Air) Ef = / C # C x(Rock) ` Al(Rock) The case in which Ef is greater than 1 indicates that the element in question is being added to the air from a source, other then its natural source. The evaluation performed in this manner, indicated that the amounts of some of the elements in Izmir are above «normal». The ele ments which exceeded normal during winter are the following: CI, V, Cr, Zn, As, Se, Br, Sb, I and Cs.VII Air qualities of different places are in general compared using the double normalization method. In this method the enrichment factor values obtained at a given place are divided by the corresponding va lues obtained at a place of reference where the ait quality is considered to be universally acceptable. In this study, the air quality in Izmir is evaluated in comparison to that in Van. Results indicate that the air in Izmir is considerably polluted. In particular the values of the, Na, C], K, V, As, Br, Sb, Cs, La and Th elements are rather high. Chapter 4 seeks a relationship between the trace elements and the total solid particulates (T. S. P.) contained in the Izmir air and the meteorological parameters. In the winter period, high T. S. P. levels were encountered during those southeasterly (S. E.) winds that were above 90 % persistent on a daily basis. Such persistent southeasterly winds occurred on the 12th through 16th days of February in the year the data was taken (1975). The presipitation in the amount of 58.1 mm/m2 that occurred on the 14th ot February cleaned the atmosphere and helped to decrease the T.S.P. content. The average T.S.P. contenat on the 12th, 13th, 15th and 16th of February amounted to 128.6 ^g/m3. This should be compared with the average T.S.P. of 85,9 /*g/m3 mea sured during highly persistent westerly winds. When the summer and winter average T.S.P. amounts are com pared, it is noted that the summer T.S.P. amounts are higher. This is due to the fact that, in Izmir, summers are hotter and much drier. In areas which remain under the effect of the maritime climate, for example in Istanbul, the Cl/Na ratio is around 1.6. On the other hand, in the province of Izmir where combined effects of both the conti nental and maritime climates are observed, this ratio displays daily variations. The Cl/Na ratio was observed to increase in the winter period and decrease in the summer period. The increase in the winter can be explaned by residential heating and traffic congestion. In the fifth chapter the trace elements and T.S.P. contained in the air of Izmir are classified according to a new method. In this method the daily measured amounts of these elements and T.S.P. are firstVIII classified into various weight categories. The frequency of occurrence in a category (i.e. number of days the element weight was measured to be in the weight interval represented by that category) is plotted against the identification number assigned to each category. The resulting curves are fitted by various theoretical curves. The follo wing equations are tried for curve - fitting. 1 - Straight line equation, 2 - Exponential curve equation, 3 - Po wer curve equation, 4 - Logarithmic curve equation, 5 - Gompertz cur ve equation, 6 - Polynomial curve equation. The results are checked with the x2 (che square) accuracy test. It is found that the polynomial curve equation exhibits close to 100 % accuracy : y = do + dxX+daX^dsX^d.x4 Following this, the coefficients of the polynomial curve equations of the elements and T.S.P. are classified again. The elements and/or T.S.P. the coefficients of which are close to each other are collected in the same category. The resulting categories are significant because they bring the elements and/or T.S.P. displaying similar features together in the same group. The sixth chapter presents the important conclusions of the study. 1. Measurements taken during the winter period indicated that the amounts of CI, V, Cr, Zn, As, Se, Br, Sb, I and Cs were much higher than what the method of enrichment factor considers normal. 2. It was concluded on the basis ot the double normalization method that the air in İzmir is considearbly dirty in comparison to that in Van which is rated clean by universal standarts. Especially, the amounts of Na, CI, K, V, As, Br, Sb, Cs, La and Th in İzmir are greater than in Van. 3. The results of the enrichment factor and the double normalization analyses indicate that the Izmir air is unacceptably dirty. Pollution is more prominent during winter.IX 4. This study has revealed that in Izmir winters are dominated by easterly winds and summers by westerly winds. The temperature diffe rence between these two periods is, on the average, 20°C. Moreover the relative humidity in the winter is 20% higher than in the summer. 5. The high T.S.P, levels of the winter are attributed to the persis tent southeasterly winds, the T.S.P. amount was found to decrease in the presence of westerly winds. Summer T.S.P. levels were found to be higher than in the winter. The reason may be traced to the dry and hot weather conditions prevailing- in İzmir during the summer months. 6. İzmir is subject to combined effects of the maritime and conti nental climates. Therefore, there are seasonal variations in the Ci/Na ratio. The winter average of this ratio is greater than the summer ave rage. This is due to the residential heating and traffic congestion that occur in the winter. 7. A classification of elements and T.S.P. has been done. For the winter period the first group, contains: Na, CI, K, Cr, Zn, Cs and La; the second group: Ti, Fe, Se, Ce and T.S.P; the 3rd group: Al, Sc, I and Th, the 4th group: V, Mn, As and Br, the 5th group Co and Sb and 6th group. Mg. For the summer period, on the other hand. 1st group is Mg, K, Sc, Ti, V, Cr, Se, Ce and Th 2nd group is CI, I and T.S.P., 3rd group is Na, Zn and As., 4th group is Mn, Fe and Cs,, 5th group is Al, Co and Sb., 6th group is Br and La. 8. The classification established in this study is significant because it brings those elements possessing similar features together, and there fore, investigation of one element gives useful information on all the other elements in the same group