Question

Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about __________ percent.

a.

5

b.

20

c.

35

d.

55

Answer: (b).20

Interact with the Community - Share Your Thoughts

Uncertain About the Answer? Seek Clarification Here.

Understand the Explanation? Include it Here.

Q. Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about __________ percent.

Similar Questions

Explore Relevant Multiple Choice Questions (MCQs)

Q. In chemical process equipments, the conical bottom heads used, usually has an apex angle of

Q. Smaller sized packings are generally dumped to the packed columns, and the large ones of size greater than __________ mm are stacked individually, which provides better control over bed porosity and offers lower gas pressure drop.

Q. Shell side heat transfer co-efficient in case of square pitch as compared to the triangular pitch under similar condition of fluid flow and tube size is

Q. Correct use of 'factor of safety' is very important in equipment design. It is defined as the ratio of the

Q. The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about __________ mm of water column per metre height of packing.

Q. The ends of a cylinderical vessel can be closed by a head, which can be one of the four shapes. For the same thickness, choose the one which can withstand the highest pressure.

Q. Pick out the correct statement.

Q. Wall thickness of schedule 40 pipe as compared to that of schedule 80 pipe is

Q. Pick out the wrong statement pertaining to the design of a basket type evaporator.

Q. Which of the following is not a graphical method (but is an analytical method) for the calculation of theoretical number of stages in case of continuous binary distillation?

Q. Saddle supports are used for supporting __________ vessels.

Q. The diameter of a propeller agitator used in agitation tank ranges from __________ percent of the tank diameter and its peripherial speed is normally 300 to 500 metres/minute.

Q. In packed towers provided with saddle packing, liquid redistributors are positioned at every __________ times column diameter or 6 metres whichever is less.

Q. Optimum reflux ratio in a continuous distillation column is determined by the

Q. Floating head heat exchangers are used for the

Q. The most common standard size of bubble caps used in industrial operation is

Q. Compensation against openings in process vessels for giving inlet and outlet connections, for providing sight glasses and manholes etc. is provided for strength and rigidity. The most efficient type of compensation is of __________ type.

Q. In case of a continuous distillation column, increase in reflux ratio may result in the

Q. In a distillation column, the minimum residence time for liquid in the downspout is about __________ seconds.

Q. Generally, elliptical dished heads

Recommended Subjects

Are you eager to expand your knowledge beyond Basic Chemical Engineering? We've handpicked a range of related categories that you might find intriguing.

Click on the categories below to discover a wealth of MCQs and enrich your understanding of various subjects. Happy exploring!