1. What is the range of yield in the Semi-chemical process?
a) 70-95%
b) 60-80%
c) 30-40%
d) 55-65%
Explanation: 60-80% is the yield of the Semi-chemical process. It is because of its two phase expansion process.
2. What does NSSC cooking liquor contain?
a) CTMP+BOD
b) CTMP+APMP
c) APMP+BOD
d) Na2So3+Na2Co3
Explanation: It uses 10-15% of the chemical charge to act as a buffer. The pH is 7-10.
3. The de-fiberator is also known as?
a) Cold stock refiner
b) Hot stock refiner
c) Neutral stock refiner
d) Maximum stock refiner
Explanation: The de-fiberator is also known as ‘Hot stock refiner’. It’s an attrition mill as make-up chemical in kraft recovery plant.
4. The _________ liquor semi-chemical pulping process for corrugating medium uses green liquor as the pulping liquor
a) Green
b) Distilled
c) Pure
d) Indigo
Explanation: The green liquor semi-chemical pulping process is for corrugating medium and uses green liquor as the pulping liquor. The green liquor can be obtained from the associated kraft mill.
5. __________ is the use of waste liquor of a semi-chemical mill as the make-up chemical in the kraft recovery plant.
a) Diagonal recovery
b) Cross recovery
c) Multi recovery
d) Instant recovery
Explanation: Cross recovery is the use of waste liquor of a semi- chemical mill as the make-up chemical in the kraft recovery plant.
6. The low ________ removal makes chemical recovery difficult in the semi-chemical process..
a) Lignin
b) Pulp
c) Hardwood
d) Softwood
Explanation: The low lignin removal makes chemical recovery difficult in the semi-chemical process. The low lignin removal makes chemical recovery difficult.
7. What is the name of the process of breaking down the chemical structure of lignin and rendering it soluble in a liquid?
a) Delignification
b) Dissolving pulp
c) Cross recovery
d) Kraft green liquor semi-chemical process
Explanation: Delignification is the name of the process of breaking down the chemical structure of lignin and rendering it soluble in a liquid. The liquid is water, except for organosolv pulping.
8.What is the correct definition of Kappa number?
a) It is the measure of the protein content of pulp
b) It is the measure of the lignin content of pulp
c) It is the measure of the minerals content of pulp
d) It is the measure of the bleaching content of pulp
Explanation: It’s the measure of the lignin content of pulp. The more the Kappa number more the Lignin content.
9. What is the other name of permanganate number?
a) L number
b) K number
c) M number
d) C number
Explanation: The number is used to monitor the amount of delignification of chemical pulps after pulping process and in between bleaching stages.
10.The pulp viscosity is a measure of the average chain length of cellulose.
a) true
b) false
Explanation: The pulp viscosity is a measure of the average chain length of cellulose. It’s determined after dissolving the pulp in a suitable solution such as cupriethylenediamine solution.