The removal of SO2 over modified activated carbon catalyst in fixed bed reactor

مقدم أطروحة جامعية

Nasir, Zaynab Adnan

مشرف أطروحة جامعية

Rauf, Shahrazad R.
Ibrahim, Niran Khalil

الجامعة

الجامعة التكنولوجية

الكلية

-

القسم الأكاديمي

قسم الهندسة الكيمياوية

دولة الجامعة

العراق

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2012

الملخص الإنجليزي

Flue gas desulfurization process has been studied in a fixed bed reactor using Modi^ed Activated Carbon (MAC) catalysts.

Activated carbon (AC) was selected as a support due to its availability, low cost, high activity towards sulfur dioxide removal and ability to be regenerated by simple methods.

The experimental set up consists of three sections: SO2 generation section, test section (reactor) and the analysis section.

The reactor was constructed from QVF column of 2.54cm inside diameter and 50cm length.

AC particles with mean particle size of (dp) =1.09 mm were used.

All the experiments were conducted at atmospheric pressure, initial SO2 concentration (Co) =2500 ppm and bed temperature was (Tbed) = 90 C, that it was the optimum temperature of Jabbar.

MAC was prepared by loading a series of nickel and copper oxides (1, 3, 5, 7, and 10) wt% onto AC.

In some of the experimental runs, the original activated carbon was pretreated with two different concentrations of nitric acid of (10 and 45) wt%.

The desulfurization performance of the MAC was investigated at ذ gas ^ow rate of 140 l/h and bed height of 4 cm.

For metal oxide loading, the results showed that the SO2 removal efficiency, breakthrough time (و0.0ل) and sorption capacity increase with increasing metal oxide loading up to a value of 7 wt% beyond which the desulfurization performance decreases.

The chemical state of the 7Ni/45NAC catalyst was characterized using XRD, it was found that NiO phase shows ma^r peaks but minor peaks for Ni, Ni(OH)2 and Ni2O3 were detected.

Moreover the removal efficiency of SO2 increases with increasing the concentration of ^O3.

The copper oxide supported catalysts showed higher desulfurization activity as compared to the nickel oxide supported catalysts, ق0.0ل for 7Cu/AC compared to 7Ni/AC increases from 3 to 4 h and sorption capacity increases from 191 to 200 mg/g.

Using 7Ni/AC catalyst, the effect of two process variables: namely flue gas flow rate of 80 < Q < 290 l/h (equivalent to 263 < Vg < 955 cm/min) and bed height of 4 < H < 8 cm on the desulfurization activity and the characteristics of the mass transfer zone (MTZ) were examined, (MTZ) is the adsorption zone in the bed in which a gradient in adsorbate concentration from zero to equilibrium.

On increasing gas ^ow rates for all bed heights a similar behavior was observed.

As the ذ gas flow rate increases, the SO2effluent concentration and breakthrough time decrease and the SO2 removal ef^ciency increases up to a point beyond which any increase in the ذ gas ^ow rate results in an increase in SO2 ef^uent concentration and breakthrough time, and the decrease in the SO2 removal ef^ciency.

The effluent concentration of SO2 decreases, the breakthrough time and the removal ef^ciency increase by increasing the bed height of the catalyst from 4 to 12 cm for all flue gas flow rates studied.

The effect of the pretreatment of the original AC with HNO^ on the characteristics of MTZ was investigated.

The Lmtz decreases and the breakthrough time (T0.05) and exhaustion time (10.95) increase by increasing the concentration of HNO^ and bed height.

On increasing the super^cial gas velocity two regions are developed.

In the £rst region, as the superficial gas velocity increases T0.05 and T0.95 decreases but the Lmtz is prolonged while in the second region, T0.05 and T0.95, and Lmtz increase as the super^cial gas velocity increases.

Based on the experimental results the Lmtz is correlated in terms of superficial gas velocity (Vg) and bed height (H) using STATISTICA software as: LMTZ 5 .

, Correlation Coefficien (R) = 0.800

التخصصات الرئيسية

العلوم الهندسية والتكنولوجية (متداخلة التخصصات)

الموضوعات

• المفاعلات الكيميائية

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-419127