Can large temperature differences in vaporizers cause operational problems?

1 Answer

Answer :

Large temperature differences in heat exchangers where liquid is vaporized are a warning flag. When  the temperature differences reach a certain value, the cooler liquid can no longer reach the heating  surface because of a vapor film. This is called film boiling. In this condition, the heat transfer  deteriorates because of the lower thermal conductivity of the vapor. If a design analysis shows that the  temperature difference is close to causing film boiling, the vaporizer should be started with the boiling  side full of relatively cooler liquid. This way, you do not start flashing the liquid. The liquid is slowly  heated up to a more stable condition. If the vaporizer is steam heated, the steam pressure should be  reduced which will reduce the temperature difference. With steam heating, take a close look at the  design if the MTD is over 90 0F this is close to the critical temperature difference where film boiling will  start.

Related questions

Description : Hi, I would like to ask if anyone here has any experience with vaporizers. I'd like to use it on some healthy herbs: D and honestly? I don't know yet which one is worth it and which one isn't: D I'll be happy for any advice :)

Last Answer : Look, if you go through the internet, you will find a lot of them there, read some reviews and you will be wiser :)

Description : An operational audit differs in many ways from an audit of financial statements. Which of the following is the best example of these differences? a. Operation audits do not ordinarily ... audit deals with operating profit while financial audit considers both the operating and net profits.

Last Answer : The boundaries of an operation audit are often drawn from anorganization chart and are not limited to a single accounting period

Description : Operational audit differs in many ways from an audit of financial statements. Which of the following is the best example of one of these differences? a. The usual audit of the financial statement ... audit are often drawn from an organization chart and are not limited to a single accounting period.

Last Answer : The boundaries of an operational audit are often drawn from an organization chart and are not limited to a single accounting period.

Description : Evaluating all the options to find out most suitable solution to business problems is interdisplinary activities. It is called - (1) Professional research (2) Management research (3) Operational research (4) Commercial research

Last Answer : (3) Operational research Explanation: Operational research is a discipline that deals with the application of advanced analytical methods to help make better decisions. Employing techniques from other ... .) is the discipline of applying advanced analytical methods to help make better decisions.

Description : Which of the following operational problems relate to the functioning of rapid gravity filter ? 1. Inadequate media comprising filter bed 2. Sludge bulking 3. Mud balls 4. Negative head 5. Incrustation of media (a) 1, 3, 4 and 5 ... 2, 3 and 4 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5

Last Answer : (a) 1, 3, 4 and 5 only

Description : Evaluating all the options to find out most suitable solution to business problems is inter-displinary activities. It is called (1) Professional research (2) Management research (3) Operational research (4) Commercial research

Last Answer : Operational research

Description : What is the major cause of selective fading? A. Small changes in the beam heading at the receiving station. B. Large changes in the height of the ionosphere, as experience at the ... Phase differences between radio wave components of the same transmission, as experienced at the receiving station.

Last Answer : D. Phase differences between radio wave components of the same transmission, as experienced at the receiving station.

Description : Will a large quantity of red ants in my raised tomato bed cause problems?

Last Answer : Need Answer

Description : When all the limiting reactant is consumed in the reaction, the operational yield __________ the relative yield. (A) Is greater than (B) Is smaller than (C) Equals (D) Can be either greater or smaller than (depends on the type of reaction)

Last Answer : (C) Equals

Description : The ratio of moles of a reactant converted into the desired product to that converted into unwanted product is called (A) Operational yield (B) Relative yield (C) Selectivity (D) None of these

Last Answer : (C) Selectivity

Description : Maximum production start up cost for making a chemical plant operational is about __________ percent of the fixed capital cost. (A) 1 (B) 5 (C) 10 (D) 30

Last Answer : (C) 10

Description : Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the (A) Packing may be crushed due to thermal expansion/contraction of the ... C) Viscosity variation of the fluids may cause channelling/flooding (D) None of these

Last Answer : (A) Packing may be crushed due to thermal expansion/contraction of the components of the equipments

Description : The rate of heat transfer from a vertical plate by natural convection depends upon the temperature differences (ΔT) between wall and outside bulk. The proportionality is given as (A) (ΔT) 1/4 (B) (ΔT) 1/2 (C) (ΔT) 5/4 (D) (ΔT) 3/4

Last Answer : (D) (ΔT) 3/4

Description : In a shell and tube type heat exchanger, the floating tube bundle heat arrangement is used (A) In low range of temperature differences (B) In high range of temperature differences (C) Because of its low cost (D) To prevent corrosion of the tube bundles

Last Answer : (B) In high range of temperature differences

Description : Terminal point temperature differences between fluids in case of a heat exchanger is termed as (A) Approach (B) Log mean temperature difference (C) Arithmetic mean temperature difference (D) Geometric mean temperature difference

Last Answer : (A) Approach

Description : Large age differences in male/female friendship (specific situation)

Last Answer : answer:I have to ask: why are you putting gasoline in a water bottle lol? You're going to have to ask him. He could just be a cool guy that also wants to hang out with someone, or he could ... nice guy that also happens to like you. Just because he's older doesn't mean he's strange or something.

Description : What is a selective fading effect? A. A fading effect caused by small changes in beam heading at the receiving station. B. A fading effect caused by phase differences between radio wave ... station D. A fading effect caused by time differences between the receiving and transmitting stations.

Last Answer : B. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station.

Description : Refers to an effect of selective fading. A. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station. B. A fading ... caused by large changes in the height of the ionosphere, as experienced at the receiving station.

Last Answer : A. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station.

Description : _______ blurs the differences between a small deployment and a large one because scale becomes tied only to demand. a) Leading b) Pooling c) Virtualization d) All of the mentioned

Last Answer : Pooling

Description : Why might differences in air pressure cause building to explode outward when a tornado passes over them?

Last Answer : The idea goes that the pressure inside a tornado is very low (which is true) while the pressure inside a building stays close to normal, which would lead to an enormous outward force on ... strong tornado these winds will tear open sections of the building and even weak tornadoes can break windows.

Description : What differences in molecular structure might cause water to form hydrogen bonds while hydrogen sulfide does not form such bonds?

Last Answer : What is the answer ?

Description : What are the similarities and differences between a third degree burn and a third degree decubitus ulcer (Consider the cause tissues affected and treatments)?

Last Answer : Need answer

Description : In a democracy, individual-differences are encouraged because Options: A) Individuals will all tend to act and think alike in the long run B) Individuals will place the good of India ahead of their ... the common cause D) The Constitution guarantees the right of the individual to act as he pleases

Last Answer : C) Individual-differences make for diverse beneficial contribution to the common cause

Description : Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the (A) Less corrosion problems (B) Flexibility possible in the baffle arrangement (C) Low pressure drop (D) High heat transfer co-efficient

Last Answer : (B) Flexibility possible in the baffle arrangement

Description : Can you use any handheld GPS system without operational satellites?

Last Answer : I don’t know about manually placing yourself and using the built-in maps, but some phones use cell towers and known wifi routers to locate themselves if they can’t see the satellites.

Description : What is an operational magnifier ? What is an operational magnifier ?

Last Answer : : A negative direct feedback magnifier with very high gain is called an operational magnifier.

Description : Is Operational Test and amp Evaluation (OT and ampE) a mandatory test that entails the testing of a production representative test article.?

Last Answer : Need answer

Description : How do you convert recipes to yield smaller and larger quantities based on operational needs?

Last Answer : Need answer

Description : What happen During the operational Test (OT) effort the purpose of validation is to determine?

Last Answer : Need answer

Description : What involvesinvolve selecting targets and striking when where and how it will best support their political or operational objective?

Last Answer : insurgent strategy

Description : What is one of the operational platoons in the forward support company (FSC)?

Last Answer : Feel Free to Answer

Description : What is Operational management system?

Last Answer : Feel Free to Answer

Description : How do strategic information systems compare with operational information system?

Last Answer : Feel Free to Answer

Description : What statement defines the Projected Operational Environment (POE)?

Last Answer : Feel Free to Answer

Description : Who was the operational commander most directly responsible for the Pacific campaign successes of Iwo Jima Okinawa and the Gilbert?

Last Answer : Feel Free to Answer

Description : What is the risk identification advantage gained by performing an Operational Analysis (Select all that apply.)?

Last Answer : Need answer

Description : How have your achievements and operational to date prepared you for this position?

Last Answer : Need answer

Description : Who is responsible for delivering the situation status update and operational assignment to the TF?

Last Answer : tf

Description : Is Allis Chalmers still operational and manufacturing equipment?

Last Answer : The company officially closed in 1998, however Allis-Chalmers Energy still remains in Houston, Texas, and in 2008, Briggs & Stratton announced they would sell lawn tractors under the Allis-Chalmers brand name.

Description : What is the operational distance for the Viper remote?

Last Answer : With an installed Viper 160xv remote starter, the starter will work fine up to a distance of 100 feet or so, but not beyond. This is the limit for 160xv Viper remote.

Description : Which is the oldest Railway station currently operational in India? A. Royapuram Station B. Howrah Station C. Bhubaneswar Station D. New Delhi Station

Last Answer : A [Royapuram Station] Explanation: Since the original structures of Bombay and Thane stations no longer exist, Royapuram station remains the oldest railway station in the entire subcontinent.

Description : Which one among the following statements regarding the constitutionally guaranteed Right to Education in India is correct? (1) This right covers both child and adult illiteracy and therefore, universally ... children between the ages of 6 to 14 years under the 86th Constitutional Amendment Act

Last Answer : (4) This right has been given to all Indian children between the ages of 6 to 14 years under the 86th Constitutional Amendment Act Explanation: The 86th amendment to the Constitution approved ... notified. It included Article 21(1) in the Indian constitution making education a fundamental right.

Description : An expenditure that has been made and cannot be recovered is called - (1) Variable cost (2) Opportunity cost (3) Sunk cost (4) Operational cost

Last Answer : (3) Sunk cost Explanation: In economics and business decision-making, sunk costs are retrospective (past) costs that have already been incurred and cannot be recovered. Sunk costs are sometimes contrasted ... is taken. The sunk cost is distinct from economic loss. Sunk costs may cause cost overrun.

Description : Which of the following is/are correct about the Operational Risk as used in the field of banking? A. Risk of loss due to inadequate or failed internal process B. Risk of loss due to natural ... Loss occurred due to non-compliance of legal procedures D. All of the Above E. None of the Above

Last Answer : A. Risk of loss due to inadequate or failed internal process Explanation: The Basel Committee defines the operational risk as the ―risk of loss resulting from inadequate or failed internal processes, people and systems or from external events‖.

Description : Which of the following will be the authorised operational units? A. BBPCU B. BBPOU C. Biller D. All of the Above E. None of the Above

Last Answer : B. BBPOU Explanation: Bharat Bill Payment Operating Units (BBPOUs) will be the authorised operational units.

Description : In which States/UT s e-Stamping is currently operational? A. Gujarat B. Karnataka C. Punjab D. All of the Above E. None of the Above

Last Answer : D. All of the Above Explanation: e-Stamping is currently operational in the States/UT s of Gujarat, Karnataka, NCT Delhi, Assam, Tamil Nadu, Rajasthan, Himachal Pradesh, Uttarakhand, UT of ... Daman & Diu, Puducherry, Uttar Pradesh, Chhattisgarh, Jharkhand, Jammu & Kashmir, Punjab and Chandigarh.

Description : An operational amplifier, as used in today's consoles, has a calculated gain of 5. This means that when the input changes _____________. A. 5 volts, the output changes 10 volts B. 10 volts, the output changes 5 volts C. 2 volts, the output changes 10 volts D. 10 volts, the output changes 2 volts

Last Answer : Answer: C

Description : What type of circuit is on card 'A0AA2' at coordinate '29Q' shown in the illustration? EL-0099 A. Operational amplifier B. Digital logic inverter C. Square wave pulse generator D. Binary counter

Last Answer : Answer: A

Description : What can be used to replace the exciter in the circuit shown in the illustration? EL-0101 A. A step-up transformer. B. A rectifier. C. A step-down transformer. D. An operational amplifier.

Last Answer : Answer: B

Description : An operational amplifier, as used in today's consoles, may have a calculated gain of 5. This means that as the input changes by ______________. A. 1 volt, the output changes 5 volts B. 5 volts, the output changes 1 volt C. 5 volts, the output changes 10 volts D. 10 volts, the output changes 5 volts

Last Answer : Answer: A