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If 100lb of black liquor containing 15lb of solids and 85lb of water is evaporated to 30lb; with a stream economy of 5 it would take 14lb of steam to remove the 70lb of water. The steam economy is about 0.8 per effect. An overall steam economy of the system is ?

If 100lb of black liquor containing 15lb of solids and 85lb of water is evaporated to 30lb; with a stream economy of 5 it would take 14lb of steam to remove the 70lb of water. The steam economy is about 0.8 per effect. An overall steam economy of the system is ? Correct Answer 4-5

An overall steam economy of 4-5, depending on the number of effects, is normally good for mill operation. Stream economy just equals to the water mass evaporated by the mass of stream used.

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A single effect evaporator is fed with 10000 kg / h of weak liquor containing 15 % caustic by weight and is concentrated to get thick liquor containing 40 % by weight caustic. Calculate: (i) kg / h of water evaporated and (ii) kg / h of thick liquor
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream, and calculate the moles of nitrogen entering the reactor and in the recycle stream?
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream, and calculate the number of moles, moles of inerts and moles of hydrogen in the recycle stream?
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream. Calculate the moles of ammonia produced.
Statement : Large number of people have become critically ill after consuming spurious liquor from a local shop. Courses of Action : I. The Government should immediately close down all the shops selling liquor till the stocks are tested for presence of toxicity. II. The owner of the liquor shop should be asked to leave the town and open a shop elsewhere. III. The owner of the liquor shop should immediately be arrested and tried for criminal negligence.
Statement : Large number of people have become critically ill after consuming spurious liquor from a local shop.

Courses of Action :
I. The Government should immediately close down all the shops selling liquor till the stocks are tested for presence of toxicity.
II. The owner of the liquor shop should be asked to leave the town and open a shop elsewhere.
III. The owner of the liquor shop should immediately be arrested and tried for criminal negligence.
A lady wants to buy the following items in the given price range- 1. Tomato between Rs. 40 and Rs. 45 per kg. 2. Grapes in the price range of Rs. 80 and Rs. 90 per kg. 3. Milk packets at Rs. 23 per liter. In which shop from the following will she definitely get all her items/ A. Shop S sells tomato at Rs. 22.5 per half kg, Grapes at Rs. 82 per kg and milk at Rs. 24 per liter. B. Shop H sells grapes at Rs. 21 per quarter kg, milk at 12.5 per half litre and tomato at Rs. 22 per half kg. C. Shop O sells milk at Rs. 11.5 per half litre, tomato at 21 per half kg and grapes at Rs. 43 per half kg. D. Shop P sells tomato at Rs. 23.5 per half kg, grapes at Rs. 85 per kg and milk at Rs. 23 per litre.
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What is the distance covered by boat N upstream in 5 hours? Which of the following option is sufficient alone to find the answer? A) Boat M is travelling downstream with 20% more downstream speed of boat N. Speed of boat M in still water is 10% more than the speed of boat N in still water. B) Boat M and Boat N are travelling downstream with speed 33 km/hr and 40 km/hr respectively and speed of boat M is still water is 2 times the speed of stream. C) Speed of boat M in still water is 6 km/hr less then speed of boat N in still water and speed of stream is 10 km/hr. D) Speed of stream is ½ times the speed of boat N in still water and downstream speed of boat M is 44 km/hr. E) Speed of stream is 10 km/hr and ratio of upstream speed of boat M and boat N is 3 : 2 respectively.