Cement & Green Concept Exam Revision Notes 2024 PDF

# Cement + Green Concept - Questions and Answers ## Complete the following: 1. Transesterification reaction for biodiesel production is - Triglycerides + Alcohol + --> Biodiesel + Glycerol 2. Hydrogen needs extensive safety measures due to its - Leakage, explosions, and associated hazards 3...

# Cement + Green Concept - Questions and Answers ## Complete the following: 1. Transesterification reaction for biodiesel production is - Triglycerides + Alcohol + --> Biodiesel + Glycerol 2. Hydrogen needs extensive safety measures due to its - Leakage, explosions, and associated hazards 3. The main components of OPC are: - C3S, C2S, - C4AF, and C3A 4. Hydrogen could be produced by: - Methane pyrolysis, - Coal gasification, while green hydrogen is mainly produced by - Electrolysis of water method. - Steam reforming of bio-based 5. Steam reforming of NG is: - Reaction of NG with steam, and the gas produced is: - Synthesis gas 6. Iron slag cement has low cost .... 7. DiCalcium Silicate is responsible for settling and early strength in ordinary Portland cement. 8. Green concepts are any approach to decrease GHG, and the following are examples of green alternatives: - Biodiesel; green H2; and green concrete. 9. Removal of humidity in pre-treatment of biodiesel is important in order to avoid saponification 10. Separation process in biodiesel industry is done to remove byproducts such as: - Glycerol; soap; excess alcohol; and water traces. 11. Rapid hardening cement differs from Portland cement as its very fine: 99.5% pass mesh 30C 12. The percentage of sulfur trioxide should not exceed 3.5% 13. The excess presence of volatile materials in cement cause cracking. 14. In green concrete, superplasticizers are added to save water. 15. Pyrolysis is a process that involves heating of biomass in the absence of oxygen. 16. In trans-esterification, ethanol is the most used alcohol because of its low cost. However, greater conversions into biodiesel can be reached using methanol. 17. Ferric oxide is used as a fluxing agent in OPC industry. 18. OPC must have a very fine size where 98% of particles must pass through a screen of 200-mesh. ## What is the most common used catalyst in Transesterification process? - Ethanol (T) ## What is added to clinker to retard the cohesion of cement? - Gypsum (T) ## What is produced by electrolysis with nuclear energy? - Yellow H2 (F) ## What is the fineness of rapid hardening cement? - 98% should pass through mesh 200 (F) ## What does a decrease in hydraulic factor mean? - Slow settling and low early strength (T) ## What is produced from NG steam reforming and released to air as Syn gas? - Blue hydrogen (F) ## What percentage of biodiesel fuel does B40 contain? - 40% (T) ## What needs less energy, buildings made from OPC or buildings made from green concrete? - OPC (F) ## What is added to the rotary furnace in cement industry? - Gypsum (F) ## Imp. Different Colors: | Color | Method/Source | Released to | |:------------------|:----------------------------|:--------------------------| | Brown H2 | Coal | Atmosphere | | Grey H2 | Steam Reforming | Air | | Black H2 | Coal Gasification | Emissions | | Blue H2 | NG Steam Reforming / Partial Oxidation of refinery residue | Captured by C and Storage | | Green H2 | Electrolysis of water (renewable) / Steam reforming of bio-based | | | Turquoise H2 | Methane pyrolysis | | | Pink/Purple H2 | Electrolysis with nuclear energy | | | Yellow H2 | Electrolysis with solar power | | | White H2 | Naturally occurs underground | Difficult to exploit | ## Manufacturing Process: Block Flow Diagram: Raw Material --> Crushing --> Grinding --> Reaction in kiln --> Clinker cooling --> Clinker grinding --> Cement - Final product. ## Simplified Block Flowsheet for Production of Biodiesel: - Triglycerides, Alcohol --> Pre-treatment --> Reaction "catalyst" --> Separation --> By-products --> Washing - Water --> Impurities --> Drying --> Storage and distribution --> FAMES. # Mid-terms Exam ## General Instructions: - The exam is composed of 3 sections - All 3 sections are to be answered in the space provided in the ANSWER SHEET except for the figures of section 3 which are to be answered in the place provided in the exam sheet. - The 3 sections are marked out of 75 marks. This will be multiplied by a factor and the full mark will be out of 20 marks. ### Section 1: (Multiple Choice) | Question | options | |:----------|:--------| |Q1 | a b c d | |Q2 | a b c d | |Q3 | a b c d | |Q4 | a b c d | |Q5 | a b c d | |Q6 | a b c d | |Q7 | a b c d | |Q8 | a b c d | |Q9 | a b c d | |Q10 | a b c d | ### Section 2: (V or X) | Question | options | |:----------|:--------| |Q51 | V X | |Q52 | V X | |Q53 | V X | |Q54 | V X | |Q55 | V X | |Q56 | V X | |Q57 | V X | |Q58 | V X | |Q59 | V X | |Q60 | V X | ### Section 3: (Fill in the blanks) | Question | options | |:----------|:--------| | Q101 | ............. liter | | Q102 |............. 9 | | Q103 |............. mol | | Q104 |............. kg | | Q105 |............. | | Q106 |............. | | Q107 | a) ............. g | | | b) ............. g | | | c) ............. liter | | | d) ............. mmHg | | Q108 | ............. Kcal/g | | Q109 | ............. g | | Q110 | a)............. | | | b)............. | ## Questions 8-10: 8. What is the pressure, in Pa, inside a 1 m³ cylinder containing 10 kg of H2(g) at 25 °C? a) [1x10^7x8.31x25]/[1x10^3] b) [5x10x8.31x298]/[1] c) [1x8.31x25]/[1x10^3] d) [5x10x8.31x298]/[1] 9. The combustion reaction of pentyl alcohol, C5H11OH and oxygen can be represented by the unbalanced equation below. C5H11OH+.... O2→..... CO2 + ..... H2O What is the coefficient for O2? a) 6.5 b) 6 c) 7.5 d) 8 10. The number of moles of air necessary for complete combustion of ethyl vinyl ketone, C5H8O is equal to, gmol: a) 6.5 b) 7 c) 32.5 d) 35 ## Section 2 - True or False Read the following statements carefully. Place "V" in front of the correct statements and "X" in front of the wrong ones. Transfer your answers to the Answer Sheet on page 1 (10 marks) - 51- If the temperature in Kelvin of 2 dm³ of an ideal gas is doubled and its pressure increased by a factor of four, the final volume will remain 2 dm³. - 52- Equal masses of gases occupy the same volume at constant temperature and pressure. - 53- The mass of 1.12 liters of gas Y at STP is found to be 6.23 g. The molar mass of gas Y is 125. - 54- Oxygen will have a density of 1.1 g/m³ at 25 °C and 0.85 atm. - 55- If equal masses of hydrogen and carbon dioxide will be placed together in the same container, their partial pressure will be equal. - 56- In van der Waals equation, a and b are constant that depends on gas type only. - 57- The pressure a gas would exert under ideal conditions is always greater than the observed pressure of a real gas. - 58- Carbon releases more energy per gram than hydrogen when burned in air. - 59- The cause of the greenhouse effect is carbon monoxide gas. - 60- Heat of combustion of CO2 equals heat of formation of C. ## Section 3 101. a) C12H26 + 8 O2 + 32 N2 --> 5 CO2 + 6 H2O + 32 N2 b) Mair = 8x32 + 32x28 = .... g c) 740 * V = (5+6+32) * 0.082 *(120+273)/760 V = ... L d) PCO2 = 5+6+32 * 440 = ... mmHg 102. q C8H18 = q C8H18 + 7 x –157 = -1330 kcal/mole C.V = 11.6 …. kcal/gm 103. C15 H4 --> C3 H2 104. 4 x 18 = 72 gm 105. 30L 106. ( P + an^2) (V-nb) = nRT n = m/M M =17 ( 20 + (4.17)^2 * 7^2) ( 7 - 17 * 0.0371) = m * 0.082 (100+273) / 17 * 0.0082 (100+273) Shift Solve ---> m = …. g 107. % = 156 *100 / 760 = ... 108. 4NH3 + 3O2 --> 2N2 + 6H2O 16 / 4 = 12 / 3 = 4 4 NH3 --> 2N2 16 ? 8 VN2 = 8 cm^3 109. 2NH3 = √2 H2S 17 ? 34 110. Cancelled # Important Note: - The provided document and image are incomplete. I've done my best to extract all the information available and convert it to a structured markdown format. - It's likely some information in the document and image is missing. If you can provide a complete version, I can give you a more accurate and comprehensive response.