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The following are equations for one tube pass bundle diameter when the tube count is known or desired: 30 Deg. DS = 1.052 x pitch x SQRT(count) + tube O.D. 90 Deg. DS = 1.13 x pitch x SQRT(count) + tube O.D. Where: Count = Number of tubes DS = Bundle diameter in INCHES Pitch = Tube spacing in inches

The following are equations for one tube pass bundle diameter when the tube count is known or desired: 30 Deg. DS = 1.052 x pitch x SQRT(count) + tube O.D. 90 Deg. DS = 1.13 x pitch x SQRT(count) + tube O.D. Where: Count = Number of tubes DS = Bundle diameter in inches Pitch = Tube spacing in inches

For normal process PLANT design LIQUID pump discharges, look for velocities in the range 5-7 ft/sec. probably not a bad idea to keep design VAPOR velocities below 125 ft/sec. These guidelines might be applied by an engineering company for design. If you are looking at plant operation, it is common to find velocities in the 9-12 ft/sec range. EROSION problems can also complicate the answer to this question. Erosion is highly dependent on the nature of the fluid. For example, 98% FI2S04 is not corrosive to carbon steel pipe, however it very erosive at "normal design" velocities. Design criteria for 98% H2S04 might be 0.70 ft/sec MAXIMUM. However, it is also well known that if the same 98% FI2S04 has a little emulsified hydrocarbon, it is substantially LESS erosive.

For normal process plant design liquid pump discharges, look for velocities in the range 5-7 ft/sec. probably not a bad idea to keep design vapor velocities below 125 ft/sec. These guidelines might be applied by an engineering company for design. If you are looking at plant operation, it is common to find velocities in the 9-12 ft/sec range. Erosion problems can also complicate the answer to this question. Erosion is highly dependent on the nature of the fluid. For example, 98% FI2S04 is not corrosive to carbon steel pipe, however it very erosive at "normal design" velocities. Design criteria for 98% H2S04 might be 0.70 ft/sec MAXIMUM. However, it is also well known that if the same 98% FI2S04 has a little emulsified hydrocarbon, it is substantially less erosive.

The INSTRUMENT air supply is guaranteed by dedicated air supply with -40 oC dew point. APART from this there is about 20 to 30 minutes of BACK up PROVIDED for emergencies like power failure, instrument air-generation failure, etc.

The instrument air supply is guaranteed by dedicated air supply with -40 oC dew point. Apart from this there is about 20 to 30 minutes of back up provided for emergencies like power failure, instrument air-generation failure, etc.

For DRY gases, you should DESIGN for a VELOCITY of about 100 ft/s while WET gases should be LIMITED to about 60 ft/s.

For dry gases, you should design for a velocity of about 100 ft/s while wet gases should be limited to about 60 ft/s.

High-pressure STEAM should be LIMITED to about 150 ft/s and low-pressure steam should be limited to about 100 ft/s.

High-pressure steam should be limited to about 150 ft/s and low-pressure steam should be limited to about 100 ft/s.

CFM and SCFM are both measures of flow rate. CFM might refer to either the flow rate of a gas or a liquid, whereas SCFM refers only to the flow rate of a gas. The same mass flow rate of a gas (i.e., lbs/minute) is equivalent to various VOLUMETRIC flow rates (i.e., CFM) depending upon the gas pressure and temperature. THUS, when gas flow rates are specified, it is very important to specify at what pressure and temperature the gas was measured. When the gas flow rate is specified as SCFM, it means that the flow rate was measured at a set of standard pressure and temperature conditions.

In the USA, the most common set of standard conditions used in industry is 60 degrees Fahrenheit and one atmosphere of pressure. Note that we have stressed most common, because there are other standard conditions that may be used. It is always BEST to spell out what standard conditions are being used (i.e., 1200 SCFM at 60 degrees F and 1 atmosphere pressure). When gas flows are expressed simply as CFM, the reader is can only speculate as to what gas temperature and pressure apply to that flow rate ... and, because of that, the CFM flow rate cannot be converted to a mass flow rate

CFM and SCFM are both measures of flow rate. CFM might refer to either the flow rate of a gas or a liquid, whereas SCFM refers only to the flow rate of a gas. The same mass flow rate of a gas (i.e., lbs/minute) is equivalent to various volumetric flow rates (i.e., CFM) depending upon the gas pressure and temperature. Thus, when gas flow rates are specified, it is very important to specify at what pressure and temperature the gas was measured. When the gas flow rate is specified as SCFM, it means that the flow rate was measured at a set of standard pressure and temperature conditions.

In the USA, the most common set of standard conditions used in industry is 60 degrees Fahrenheit and one atmosphere of pressure. Note that we have stressed most common, because there are other standard conditions that may be used. It is always best to spell out what standard conditions are being used (i.e., 1200 SCFM at 60 degrees F and 1 atmosphere pressure). When gas flows are expressed simply as CFM, the reader is can only speculate as to what gas temperature and pressure apply to that flow rate ... and, because of that, the CFM flow rate cannot be converted to a mass flow rate

This question depends on many factors. It sounds like the tower is small. A RULE of THUMB suggests that the tower will see an evaporation loss of about 0.1% of the circulation flowrate for each Fahrenheit degree of cooling. Other LOSSES INCLUDE drift losses (probably very small for your tower) and blow down. Blow down is simply a purge of tower water to prohibit the BUILDUP of solids.

This question depends on many factors. It sounds like the tower is small. A rule of thumb suggests that the tower will see an evaporation loss of about 0.1% of the circulation flowrate for each Fahrenheit degree of cooling. Other losses include drift losses (probably very small for your tower) and blow down. Blow down is simply a purge of tower water to prohibit the buildup of solids.

If you have excessive pressure drop across the control valve and the downstream pressure is low enough to cause the liquid to flash, a great deal of NOISE in the control valve can result. Excessive damage can be done as WELL. This is a common PROBLEM at low flows. Review the DESIGN information on the valve and the process to see if low flow may be the problem. If the valve is INCORRECTLY sized the noise will be apparent from the day of installation. If flows have recently been changed, the valve may have been designed correctly at the time, but is too large for current operation.

If you have excessive pressure drop across the control valve and the downstream pressure is low enough to cause the liquid to flash, a great deal of noise in the control valve can result. Excessive damage can be done as well. This is a common problem at low flows. Review the design information on the valve and the process to see if low flow may be the problem. If the valve is incorrectly sized the noise will be apparent from the day of installation. If flows have recently been changed, the valve may have been designed correctly at the time, but is too large for current operation.

The HEAT of COMBUSTION of ammonia is 8,000 Btu per POUND. There is no reason why it cannot be combusted with or without auxiliary fuel. HOWEVER, ammonia combustion does result in a flue gas having a high concentration of NOx and the design of a combustion chamber for ammonia requires SPECIAL conditions to mitigate or reduce the level of NOx emissions.

The heat of combustion of ammonia is 8,000 Btu per pound. There is no reason why it cannot be combusted with or without auxiliary fuel. However, ammonia combustion does result in a flue gas having a high concentration of NOx and the design of a combustion chamber for ammonia requires special conditions to mitigate or reduce the level of NOx emissions.

Flameless oxidizers are used to treat volatile organic compounds (VOC) and liquid organic streams. Traditionally, these types of streams were combusted to break down the molecules. The disadvantage of this treatment method was the formation of NOx. Flameless oxidizers use electrically HEATED ceramic packing and a high velocity introduction system to initiate the destruction of the organic compounds into carbon dioxide and water. Once this oxidation reaction begins, it continues via self-perpetuation. Capital cost for such systems are usually about 25% less than traditional combustion systems and CAPACITIES can range from 250 to 40,000 SCFM (standard cubic feet per minute). Thermatrix Inc. is the pioneer for this TECHNOLOGY. Visit their website below.

Flameless oxidizers are used to treat volatile organic compounds (VOC) and liquid organic streams. Traditionally, these types of streams were combusted to break down the molecules. The disadvantage of this treatment method was the formation of NOx. Flameless oxidizers use electrically heated ceramic packing and a high velocity introduction system to initiate the destruction of the organic compounds into carbon dioxide and water. Once this oxidation reaction begins, it continues via self-perpetuation. Capital cost for such systems are usually about 25% less than traditional combustion systems and capacities can range from 250 to 40,000 SCFM (standard cubic feet per minute). Thermatrix Inc. is the pioneer for this technology. Visit their website below.

A. Duprey CONDUCTED testing on an electrostatic precipitator in a PULP MILL. The results were published in a National Air Pollution Control Administration report called "Compilation of air POLLUTANT Emission Factors".

A. Duprey conducted testing on an electrostatic precipitator in a pulp mill. The results were published in a National Air Pollution Control Administration report called "Compilation of air Pollutant Emission Factors".

OEG Company in Osaka, JAPAN commercialized a device called Pushkun that RUNS through pipes and "pushes" out left over product. The system is particularly valuable in batch OPERATIONS where product recovery is chief concern. The manufacturer claims that at one installation, the system paid for itself in four months through product recovery. System costs depend on the scale of the system, but are TYPICALLY around $10,000 US (1998).

OEG Company in Osaka, Japan commercialized a device called Pushkun that runs through pipes and "pushes" out left over product. The system is particularly valuable in batch operations where product recovery is chief concern. The manufacturer claims that at one installation, the system paid for itself in four months through product recovery. System costs depend on the scale of the system, but are typically around $10,000 US (1998).

API RP 520 gives EQUATIONS to calculate relief requirements. For thermal relief, a very simple FORMULA requires the heat input and the coefficient of thermal expansion of the liquid. The heat input could be a problem. If you are concerned about sulfur in a line that is part of a heat EXCHANGER system, then the heat is simply the design capacity of the heat exchanger. If it were a pipeline in the sun, then you would have to calculate the amount of heat that the sun can put into the pipe. You can get the coefficient of thermal expansion from your supplier or any book on sulfuric. You can also calculate it by taking the specific gravity at two different temperatures and divide the SG difference by the temperature difference. Coefficient of expansion has the units of 1/0F. Now for the easy part, if you are at all concerned, just put in a 3/4" x 1" thermal relief valve and do not worry about doing any calculations. However, I do not believe sulfuric has any problems in pipelines unless it is a very long ONE and directly in the sun. In addition, I would make it a standard procedure to drain the line if it will sit dead headed for any significant period. Just a small bleed will be enough.

API RP 520 gives equations to calculate relief requirements. For thermal relief, a very simple formula requires the heat input and the coefficient of thermal expansion of the liquid. The heat input could be a problem. If you are concerned about sulfur in a line that is part of a heat exchanger system, then the heat is simply the design capacity of the heat exchanger. If it were a pipeline in the sun, then you would have to calculate the amount of heat that the sun can put into the pipe. You can get the coefficient of thermal expansion from your supplier or any book on sulfuric. You can also calculate it by taking the specific gravity at two different temperatures and divide the SG difference by the temperature difference. Coefficient of expansion has the units of 1/0F. Now for the easy part, if you are at all concerned, just put in a 3/4" x 1" thermal relief valve and do not worry about doing any calculations. However, I do not believe sulfuric has any problems in pipelines unless it is a very long one and directly in the sun. In addition, I would make it a standard procedure to drain the line if it will sit dead headed for any significant period. Just a small bleed will be enough.

In your CASE, you essentially have two reactions: CH4 + 3/2 O2 ---> CO + 2 H2O (incomplete combustion) CH4 + 2 O2 ---> CO2 + 2 H2O (complete combustion) each of these reactions has a specific RATE at which it occurs. If you wanted to design a reactor properly, you would need to determine the conversion of methane in each of the above reactions. The upper limit of your flow rate is bound by the rate of reaction. If the flow rate is too high, the reaction simply will not take place (i.e. the flame will burn out). I am not sure that there is a simple relationship between pressure and flow rate in this case. The GASES need to spend a CERTAIN amount of time in the reactor in order for the combustion to take place (residence time). Once you know the residence time, you COULD design a reactor for your specific flow rate.

In your case, you essentially have two reactions: CH4 + 3/2 O2 ---> CO + 2 H2O (incomplete combustion) CH4 + 2 O2 ---> CO2 + 2 H2O (complete combustion) each of these reactions has a specific rate at which it occurs. If you wanted to design a reactor properly, you would need to determine the conversion of methane in each of the above reactions. The upper limit of your flow rate is bound by the rate of reaction. If the flow rate is too high, the reaction simply will not take place (i.e. the flame will burn out). I am not sure that there is a simple relationship between pressure and flow rate in this case. The gases need to spend a certain amount of time in the reactor in order for the combustion to take place (residence time). Once you know the residence time, you could design a reactor for your specific flow rate.

During the welding process, the two metal pieces being joined are subject to extreme TEMPERATURES and can cause the crystalline structure of the metal to pass through various metallurgical phases. As a result, hardening (and embrittlement) of the metal can occur to varying degrees (usually dependent on carbon content). Heat treatment is designed to reduce the hardness in the heat-affected zone of the METALS and increase ductility in these sections. Various pressure vessel codes contain the SPECIFICS regarding the procedures for post-weld heat treatment. Heat is usually held for one hour per inch of THICKNESS of the metal. The TEMPERATURE used is based on the "P-number" of the metals. P-numbers are assigned based on the chemical composition of the metals. Holding temperatures can range from 1100-1350 °F (593-732 °C).

During the welding process, the two metal pieces being joined are subject to extreme temperatures and can cause the crystalline structure of the metal to pass through various metallurgical phases. As a result, hardening (and embrittlement) of the metal can occur to varying degrees (usually dependent on carbon content). Heat treatment is designed to reduce the hardness in the heat-affected zone of the metals and increase ductility in these sections. Various pressure vessel codes contain the specifics regarding the procedures for post-weld heat treatment. Heat is usually held for one hour per inch of thickness of the metal. The temperature used is based on the "P-number" of the metals. P-numbers are assigned based on the chemical composition of the metals. Holding temperatures can range from 1100-1350 °F (593-732 °C).

PCB is a commonly used acronym for "PolyChlorinated Biphenyls". These compounds are famous for the DISPOSAL problems that they POSE to the chemical industry.

PCB is a commonly used acronym for "PolyChlorinated Biphenyls". These compounds are famous for the disposal problems that they pose to the chemical industry.

Changing the color of copper by means of chemical reactions is a dangerous Endeavour that I really do not recommend. However, there is something you can do to get a green color, if fact if you are familiar with the Statue of Liberty here in America, this would EXPLAIN why it is green. You see, the outside of the statue is coated with copper and being in New York City, it is subjected to acid rain. This causes the formation of another chemical that coats the copper and gives the statue its green color. The two acids that you can use are nitric acid (which works best) or sulfuric acid (which will probably require some gentle heating along with the acid). I am not sure if there were a good way to get nitric acid out of something you may have around the house, you would probably have to buy it.

Sulfuric acid can be obtained from car batteries (the liquid inside). You will want to boil the mixture (to concentrate it by evaporating the water), until you see WHITE fumes (which are very dangerous). Then put your copper is while the acid is hot and leave it there until you get the color you would like. If you are going to do this, please do it outside or in a well ventilated area and make sure you have some baking soda HANDY is CASE you get some of the acid on your skin. If you are looking for a DIFFERENT color or more colors...

Changing the color of copper by means of chemical reactions is a dangerous Endeavour that I really do not recommend. However, there is something you can do to get a green color, if fact if you are familiar with the Statue of Liberty here in America, this would explain why it is green. You see, the outside of the statue is coated with copper and being in New York City, it is subjected to acid rain. This causes the formation of another chemical that coats the copper and gives the statue its green color. The two acids that you can use are nitric acid (which works best) or sulfuric acid (which will probably require some gentle heating along with the acid). I am not sure if there were a good way to get nitric acid out of something you may have around the house, you would probably have to buy it.

Sulfuric acid can be obtained from car batteries (the liquid inside). You will want to boil the mixture (to concentrate it by evaporating the water), until you see white fumes (which are very dangerous). Then put your copper is while the acid is hot and leave it there until you get the color you would like. If you are going to do this, please do it outside or in a well ventilated area and make sure you have some baking soda handy is case you get some of the acid on your skin. If you are looking for a different color or more colors...

If Q/d2.5 is GREATER than or equal to about 10.2, then the pipe is SAID to full. In this CASE, Q is in GPM (U.S. Imperial gallons per minute) and d is in inches. REFERENCE: Pocket GUIDE to Chemical Engineering, ISBN: 0884153118

If Q/d2.5 is greater than or equal to about 10.2, then the pipe is said to full. In this case, Q is in GPM (U.S. Imperial gallons per minute) and d is in inches. Reference: Pocket Guide to Chemical Engineering, ISBN: 0884153118

Screw compressors utilize a pair of "meshing" HELICAL screws to compress gases. These types of compressors a generally appropriate for a flow range of 85-170 m3/h (3000-6000 acfm) and DISCHARGE pressures in the range of 2070-2760 kPa (300-400 psig). As the NAME implies, DRY screw compressor run dry while oil-flooded compressors use oil for bearing lubrication as well as to seal the compression chamber. The oil also carries the heat from the compression away from the compressor. This heat is TYPICALLY rejected to an external heat exchanger. Some factors to consider when choosing between the two types of screw compressors include

Is the process gas compatible with the oil? If the answer is no, use dry type Does the process gas have to be oil free? If the answer is yes, use dry type is efficiency the top priority. If the answer is yes, use oil-flooded type Are you looking to minimize shaft-seal leakage. If the answer is yes, use oil-flooded type Are there any liquids in the incoming gas. If the answer is yes, use oil-flooded type Does the gas contain small particulate matter? If the answer is yes, use dry type these and other guidelines can help in choosing between the two types of screw compressors.

Screw compressors utilize a pair of "meshing" helical screws to compress gases. These types of compressors a generally appropriate for a flow range of 85-170 m3/h (3000-6000 acfm) and discharge pressures in the range of 2070-2760 kPa (300-400 psig). As the name implies, dry screw compressor run dry while oil-flooded compressors use oil for bearing lubrication as well as to seal the compression chamber. The oil also carries the heat from the compression away from the compressor. This heat is typically rejected to an external heat exchanger. Some factors to consider when choosing between the two types of screw compressors include

Is the process gas compatible with the oil? If the answer is no, use dry type Does the process gas have to be oil free? If the answer is yes, use dry type is efficiency the top priority. If the answer is yes, use oil-flooded type Are you looking to minimize shaft-seal leakage. If the answer is yes, use oil-flooded type Are there any liquids in the incoming gas. If the answer is yes, use oil-flooded type Does the gas contain small particulate matter? If the answer is yes, use dry type these and other guidelines can help in choosing between the two types of screw compressors.

The accuracy of vortex flowmeters can be WITHIN 1% so long as they're being operating within their recommended flow range, have a steady STREAM, and you have 10 PIPE DIAMETERS of straight pipe behind the in FRONT of the flowmeters. Outside of these parameters, these flowmeters are not accurate.

The accuracy of vortex flowmeters can be within 1% so long as they're being operating within their recommended flow range, have a steady stream, and you have 10 pipe diameters of straight pipe behind the in front of the flowmeters. Outside of these parameters, these flowmeters are not accurate.

Gear pumps are a type of positive displacement pump that are APPROPRIATE for pumping relatively high PRESSURES and low capacities. Advantages include the ability to handle a wide range of viscosities, less sensitivity to cavitation (than centrifugal style pumps), relatively simple to maintain and rebuild. DISADVANTAGES can include a limited array of materials of construction due to TIGHT tolerances required, high SHEAR placed on the liquid, and the fluid must be free of abrasives. Also, note that gear pumps must be controlled via the motor speed. Throttling the discharge is not an acceptable means of control.

Gear pumps are a type of positive displacement pump that are appropriate for pumping relatively high pressures and low capacities. Advantages include the ability to handle a wide range of viscosities, less sensitivity to cavitation (than centrifugal style pumps), relatively simple to maintain and rebuild. Disadvantages can include a limited array of materials of construction due to tight tolerances required, high shear placed on the liquid, and the fluid must be free of abrasives. Also, note that gear pumps must be controlled via the motor speed. Throttling the discharge is not an acceptable means of control.

Sieder and Tate recommended the following for DETERMINE friction factors INSIDE heat exchanger tubes with varying temperatures: First, determine the average, bulk mean temperature in the processing line. For example if the FLUID enters the line at 300 °C and leaves at 280 °C, use 290 °C to determine the physical PROPERTIES and friction factors. As for corrections: Laminar FLOW If the liquid is cooling, the friction factor obtained from the mean temperature and bulk properties is divided by (bulk viscosity/wall viscosity)0.23 and for heating, it's divided by (bulk viscosity/wall viscosity)0.38. Here, the bulk and wall viscosity are determined at the mean temperature over the length of the line. Turbulent Flow If the liquid is cooling, the friction factor obtained from the mean temperature and bulk properties is divided by (bulk viscosity/wall viscosity)0.11 and for heating, it's divided by (bulk viscosity/wall viscosity)0.17.

Sieder and Tate recommended the following for determine friction factors inside heat exchanger tubes with varying temperatures: First, determine the average, bulk mean temperature in the processing line. For example if the fluid enters the line at 300 °C and leaves at 280 °C, use 290 °C to determine the physical properties and friction factors. As for corrections: Laminar Flow If the liquid is cooling, the friction factor obtained from the mean temperature and bulk properties is divided by (bulk viscosity/wall viscosity)0.23 and for heating, it's divided by (bulk viscosity/wall viscosity)0.38. Here, the bulk and wall viscosity are determined at the mean temperature over the length of the line. Turbulent Flow If the liquid is cooling, the friction factor obtained from the mean temperature and bulk properties is divided by (bulk viscosity/wall viscosity)0.11 and for heating, it's divided by (bulk viscosity/wall viscosity)0.17.

This application is NEARLY perfect for a turbine REGENERATIVE type of pump. Factors that immediately identify your application and pump type are the small flow rate, low NPSHa, and high temperature. The regenerative turbine was specifically developed for these conditions and one more: high discharge pressures. The high discharge pressure MAY not be necessary, but the regenerative turbine can give you an NPSHr of 0.5 feet with ease. They are particularly suited to saturated boiler feed water and your application is similar, ALBEIT not in pressure. You can visit the SITE below to learn more about these types of pumps.

This application is nearly perfect for a turbine regenerative type of pump. Factors that immediately identify your application and pump type are the small flow rate, low NPSHa, and high temperature. The regenerative turbine was specifically developed for these conditions and one more: high discharge pressures. The high discharge pressure may not be necessary, but the regenerative turbine can give you an NPSHr of 0.5 feet with ease. They are particularly suited to saturated boiler feed water and your application is similar, albeit not in pressure. You can visit the site below to learn more about these types of pumps.

Any device that restricts the flow to PERFORM measurements is not recommended for slurries. These DEVICES include orifices and dampeners. These devices can lead to liquid/solid SEPARATION and they can lead to excessive erosion. Instead, MEASURING devices that do not restrict the flow should be used. ONE example of such a device is the magnetic flow meter.

Any device that restricts the flow to perform measurements is not recommended for slurries. These devices include orifices and dampeners. These devices can lead to liquid/solid separation and they can lead to excessive erosion. Instead, measuring devices that do not restrict the flow should be used. One example of such a device is the magnetic flow meter.

If POSSIBLE, SLURRY lines should indeed be sloped. Generally, to slope the pipes 1/2 inches for EVERY 10 feet of PIPE is RECOMMENDED.

If possible, slurry lines should indeed be sloped. Generally, to slope the pipes 1/2 inches for every 10 feet of pipe is recommended.

Bypass LINES should be placed ABOVE the control VALVE so that the SLURRY cannot settle out and BUILD up in the line during bypass.

Bypass lines should be placed ABOVE the control valve so that the slurry cannot settle out and build up in the line during bypass.

Typically straight-through DIAPHRAGM, clamp or pinch, and full-port ball valves with cavity FILLERS are the PREFERRED type of SLURRY valves. In general, gate, needle, and GLOBE valves are NOT recommended for slurry services.

Typically straight-through diaphragm, clamp or pinch, and full-port ball valves with cavity fillers are the preferred type of slurry valves. In general, gate, needle, and globe valves are NOT recommended for slurry services.

The specific roughness for welded, seamless steel is .0002 ft. PVC has a specific roughness of 0.000005 ft. You may also want to CONSIDER using the Hazen-Williams formula, which lists a COEFFICIENT of 130-140 for cement-lined cast iron PIPING. You need to decide which is more conservative for your APPLICATION.

The specific roughness for welded, seamless steel is .0002 ft. PVC has a specific roughness of 0.000005 ft. You may also want to consider using the Hazen-Williams formula, which lists a coefficient of 130-140 for cement-lined cast iron piping. You need to decide which is more conservative for your application.

The MOTOR AMPERAGE should be measured in the field with the pump discharge valve wide open. Subtract about 10% from the pumps maximum rated amperage. Than the maximum impeller size can be determined from A2 = A1 (d2/d1)3 A2 = Maximum amperage minus 10% A1 = Current operating amperage d2 = Maximum impeller diameter d1 = Current impeller diameter

The motor amperage should be measured in the field with the pump discharge valve wide open. Subtract about 10% from the pumps maximum rated amperage. Than the maximum impeller size can be determined from A2 = A1 (d2/d1)3 A2 = Maximum amperage minus 10% A1 = Current operating amperage d2 = Maximum impeller diameter d1 = Current impeller diameter

The MINIMUM flow that a pump requires DESCRIBES the flow below which the pump will experience what is called "shutoff". At shutoff, most of the pump's horsepower or WORK is converted to heat that can vaporize the fluid and cause cavitations that will severely damage the pump. The minimum flow of a pump is particularly important in the design of boiler feed pumps where the fluid is NEAR its boiling point.

The minimum flow that a pump requires describes the flow below which the pump will experience what is called "shutoff". At shutoff, most of the pump's horsepower or work is converted to heat that can vaporize the fluid and cause cavitations that will severely damage the pump. The minimum flow of a pump is particularly important in the design of boiler feed pumps where the fluid is near its boiling point.

The FOLLOWING method, developed by M.W. KELLOGG, gives RESULTS within 3.5% of most manufacturers’ curves. EFF % = 80-0.2855H+3.78x10-4HF-2.23x10-7HF2+5.39x10-4H2-6.39x10-7H2F+4.0x10-10H2F2 H = Developed head, ft F = Flow in GPM (gallons per minute) Applicable for heads from 50 to 300 ft and flows from 100 to 1000 GPM

The following method, developed by M.W. Kellogg, gives results within 3.5% of most manufacturers’ curves. Eff % = 80-0.2855H+3.78x10-4HF-2.23x10-7HF2+5.39x10-4H2-6.39x10-7H2F+4.0x10-10H2F2 H = Developed head, ft F = Flow in GPM (gallons per minute) Applicable for heads from 50 to 300 ft and flows from 100 to 1000 GPM

TRY this handy little equation: Horsepower = (GPM)(Delivered Pressure) / 1715 (Efficiency) GPM = Gallon per MINUTE of flow Delivered pressure = Discharge minus SUCTION pressure, PSI Efficiency = Fractional pump efficiency

Try this handy little equation: Horsepower = (GPM)(Delivered Pressure) / 1715 (Efficiency) GPM = Gallon per minute of flow Delivered pressure = Discharge minus suction pressure, psi Efficiency = Fractional pump efficiency

1. CAPACITY VARIES directly with impeller diameter and SPEED.
2. Head varies directly with the SQUARE of impeller diameter and speed.
3. Horsepower varies directly with the CUBE of impeller diameter and speed.

You can use the Weymouth equation to estimate the gas FLOW. Below is the equation. The compressibility should be EVALUATED at Pavg SHOWN below. Nomenclature is as follows: Q = flow RATE, Million Cubic Feet per Day (MCFD) Tb = base Temperature, degrees Rankin Pb = base pressure, psia G = gas specific GRAVITY (reference air=1) L = line length, miles T = gas temperature, degrees Rankin Z = gas compressibility factor D = pipe inside diameter, in. E = Efficiency factor E=1 for new pipes with no bends E=0.95 for pipe less than a year old E=0.92 for average operating conditions E=0.85 for unfavorable operating conditions

You can use the Weymouth equation to estimate the gas flow. Below is the equation. The compressibility should be evaluated at Pavg shown below. Nomenclature is as follows: Q = flow rate, Million Cubic Feet per Day (MCFD) Tb = base Temperature, degrees Rankin Pb = base pressure, psia G = gas specific gravity (reference air=1) L = line length, miles T = gas temperature, degrees Rankin Z = gas compressibility factor D = pipe inside diameter, in. E = Efficiency factor E=1 for new pipes with no bends E=0.95 for pipe less than a year old E=0.92 for average operating conditions E=0.85 for unfavorable operating conditions

The RELATIONSHIP SHOWN below is valid for REYNOLDS numbers in the range of 2100 to 106. For SMOOTH tubes, a constant of 23,000 should be used rather than 20,000.

The relationship shown below is valid for Reynolds numbers in the range of 2100 to 106. For smooth tubes, a constant of 23,000 should be used rather than 20,000.

A screen analysis is the one passes solids through various sizes of screen MESH. This is done to get a PARTICLE SIZE distribution. A group of solids is first passes through fine mesh and the amount that passes is noted, then a little larger mesh and the amount recorded and so on.

A screen analysis is the one passes solids through various sizes of screen mesh. This is done to get a particle size distribution. A group of solids is first passes through fine mesh and the amount that passes is noted, then a little larger mesh and the amount recorded and so on.

Consider a rotational viscometer. It will measure the shear rate applied and the subsequent viscosity at the same time. You can also vary the temperature and time the STRESSES are applied for the truly "fun" non-Newtonian fluids. According to Cole-Parmer, "The rotational viscometer measures viscosity by determining the viscous resistance of the fluid. This measurement is obtained by immersing a spindle into the test fluid. The viscometer measures the additional torque required for the spindle to overcome viscous resistance and regain constant speed. This value is then CONVERTED to centipoises and DISPLAYED on the instrument's LCD readout." When testing a TOMATO sauce sample, the following results were observed: "A sample of tomato sauce was analyzed to determine the product's viscosity profile. The test was conducted at a temperature of 25°C. An up/down speed ramp was performed from 10 to 100 RPM, giving a viscosity RANGE of from 3,800 to 632.5 cP, over shear rates from 3.4 to 34.0 reciprocal seconds. The test data obtained for tomato sauce shows that this product exhibits a marked shear thinning viscosity profile over the test conditions.

Consider a rotational viscometer. It will measure the shear rate applied and the subsequent viscosity at the same time. You can also vary the temperature and time the stresses are applied for the truly "fun" non-Newtonian fluids. According to Cole-Parmer, "The rotational viscometer measures viscosity by determining the viscous resistance of the fluid. This measurement is obtained by immersing a spindle into the test fluid. The viscometer measures the additional torque required for the spindle to overcome viscous resistance and regain constant speed. This value is then converted to centipoises and displayed on the instrument's LCD readout." When testing a tomato sauce sample, the following results were observed: "A sample of tomato sauce was analyzed to determine the product's viscosity profile. The test was conducted at a temperature of 25°C. An up/down speed ramp was performed from 10 to 100 RPM, giving a viscosity range of from 3,800 to 632.5 cP, over shear rates from 3.4 to 34.0 reciprocal seconds. The test data obtained for tomato sauce shows that this product exhibits a marked shear thinning viscosity profile over the test conditions.

It is common to have a LOCATION in the suction line of the pump to detect the helium. Then, the helium source is passed over the flanges and other possible SOURCES of leakage. This is done while monitoring the detector at the pump suction for detectable amount of helium. Alternatively, if your system can take pressure as well as vacuum you can try pressuring it up and looking for the leaks that WAY. As yet another alternative, you can install an IR UNIT to the suction of the pump and spray isopropyl alcohol on the flanges.

It is common to have a location in the suction line of the pump to detect the helium. Then, the helium source is passed over the flanges and other possible sources of leakage. This is done while monitoring the detector at the pump suction for detectable amount of helium. Alternatively, if your system can take pressure as well as vacuum you can try pressuring it up and looking for the leaks that way. As yet another alternative, you can install an IR unit to the suction of the pump and spray isopropyl alcohol on the flanges.

In titrations, a common ERROR MADE is that the technicians stop at the phenolphthalein endpoint (which is incorrect) rather than the METHYL orange endpoint (which is correct). STOPPING the titration too soon can cause the results to be grossly under-reported. Equation

1. 2NaOH + H2S -> Na2S + 2H20 Equation
2. Na2S + H2S -> 2NaSH Overall Equation: NaOH + H2S -> NASH + H2O

In titrations, a common error made is that the technicians stop at the phenolphthalein endpoint (which is incorrect) rather than the methyl orange endpoint (which is correct). Stopping the titration too soon can cause the results to be grossly under-reported. Equation

A method known as Fourier transform-infrared (FT-IR) SPECTROSCOPY is often used for this purpose. FT-IR sends light beams of varying wavelength through the sample and the reflected light is analyzed by spectroscopy to find the absorption of each wavelength. The measured WAVELENGTHS are COMPARED with a reference laser and the sample composition can be calculated. Analect Instruments Inc. SPECIALIZES in FT-IR measurement.

A method known as Fourier transform-infrared (FT-IR) spectroscopy is often used for this purpose. FT-IR sends light beams of varying wavelength through the sample and the reflected light is analyzed by spectroscopy to find the absorption of each wavelength. The measured wavelengths are compared with a reference laser and the sample composition can be calculated. Analect Instruments Inc. specializes in FT-IR measurement.

BELLOW expansion joints have gained a reputation for being "weak" points in piping. Usually they are used to remove piping stresses from EQUIPMENT or to allow for MINOR piping moments. If they are used PROPERLY, expansion joints can save equipment and/or equipment welds from stresses generated from piping forces. The two most common COMPLAINTS about bellows are

1. They tend to build up dirt
2. They are "weak" point in piping (as noted earlier).

To overcome these issues, manufacturers can began installing drains in the bellows to allow for the period purging of material. Additionally, bellow manufacturers have placed much emphasis on installation advice and showing their customers how to protect the bellow from unnecessary damage. One such method is the use of tie rods between the end flanges to avoid pressure thrust movements (beyond the bellow's design conditions) which are often the cause of bellow failures

Bellow expansion joints have gained a reputation for being "weak" points in piping. Usually they are used to remove piping stresses from equipment or to allow for minor piping moments. If they are used properly, expansion joints can save equipment and/or equipment welds from stresses generated from piping forces. The two most common complaints about bellows are

To overcome these issues, manufacturers can began installing drains in the bellows to allow for the period purging of material. Additionally, bellow manufacturers have placed much emphasis on installation advice and showing their customers how to protect the bellow from unnecessary damage. One such method is the use of tie rods between the end flanges to avoid pressure thrust movements (beyond the bellow's design conditions) which are often the cause of bellow failures

Where carbon steel is an appropriate material of construction, NACE (National Association of Corrosion Engineers) has issued the following standard: NACE RP0472, "Methods and controls to prevent in-service ENVIRONMENTAL cracking of carbon-steel weldments in corrosive petroleum refining environments”. For welds where HARDNESS testing is required, RP0472 give the following guidelines: A. Testing shall be TAKEN with a portable Brinell hardness tester. Test technique guidelines are given in an appendix in the standard. B. Testing shall be done on the process side whenever possible. C. For vessel or tank butt welds, one test per 10 feet of seam with a minimum of one location per seam is required. One test shall be done on each nozzle flange-to-neck and nozzle neck-to-shell (or neck-to-head) weld. D. A percentage of helping welds shall be TESTED (5 percent minimum is suggested). E. Testing of fillet welds should be done when feasible (with the testing frequency similar to the butt welds). F. Each welding procedure used shall be tested. G. Welds that exceed 200 Brinell shall be heat treated or removed.

Where carbon steel is an appropriate material of construction, NACE (National Association of Corrosion Engineers) has issued the following standard: NACE RP0472, "Methods and controls to prevent in-service environmental cracking of carbon-steel weldments in corrosive petroleum refining environments”. For welds where hardness testing is required, RP0472 give the following guidelines: A. Testing shall be taken with a portable Brinell hardness tester. Test technique guidelines are given in an appendix in the standard. B. Testing shall be done on the process side whenever possible. C. For vessel or tank butt welds, one test per 10 feet of seam with a minimum of one location per seam is required. One test shall be done on each nozzle flange-to-neck and nozzle neck-to-shell (or neck-to-head) weld. D. A percentage of helping welds shall be tested (5 percent minimum is suggested). E. Testing of fillet welds should be done when feasible (with the testing frequency similar to the butt welds). F. Each welding procedure used shall be tested. G. Welds that exceed 200 Brinell shall be heat treated or removed.

Tanks CONSTRUCTED prior to the 1950's are notorious for failing along the shell-to-bottom seam or on the side seam. The PRINCIPLE reason for this is that these tanks were constructed before there were established procedures and codes for such a tank (Ex/ API-650 "WELDED Steel Tanks for Oil Storage"). ONE of the key features of these codes and procedures was to make sure that tanks were designed to FAIL along the shell-to-seam such that the liquid remained largely contained.

Tanks constructed prior to the 1950's are notorious for failing along the shell-to-bottom seam or on the side seam. The principle reason for this is that these tanks were constructed before there were established procedures and codes for such a tank (Ex/ API-650 "Welded Steel Tanks for Oil Storage"). One of the key features of these codes and procedures was to make sure that tanks were designed to fail along the shell-to-seam such that the liquid remained largely contained.

Tank Blanketing Valves provided an effective means of PREVENTING and CONTROLLING fires in flammable liquid storage tanks. Vapors cannot be ignited in the absence of an adequate supply of oxygen. In most instances, this oxygen is provided by air drawn into the tank from the atmosphere during tank emptying operations. Tank Blanketing Valves are installed with their inlet connected to a supply of PRESSURIZED inert gas (usually Nitrogen), and their outlet piped into the tanks vapor SPACE. When the tank pressure drops below a predetermined level, the blanketing valve opens and allows a flow of inert gas into the vapor space. The blanketing valve reseals when pressure in the tank has returned to an acceptable level.

Tank Blanketing Valves provided an effective means of preventing and controlling fires in flammable liquid storage tanks. Vapors cannot be ignited in the absence of an adequate supply of oxygen. In most instances, this oxygen is provided by air drawn into the tank from the atmosphere during tank emptying operations. Tank Blanketing Valves are installed with their inlet connected to a supply of pressurized inert gas (usually Nitrogen), and their outlet piped into the tanks vapor space. When the tank pressure drops below a predetermined level, the blanketing valve opens and allows a flow of inert gas into the vapor space. The blanketing valve reseals when pressure in the tank has returned to an acceptable level.

Mr. Alex C. Hoffmann of the Stratingh Institute for Chemistry and Chemical Engineering states: "Whether a material can be fluidized at all is the question: if it is fine or STICKY, the bed will be cohesive. It will then tend to FORM channels through which the aeration gas will escape RATHER than being DISPERSED through the interstices supporting the particles. In the other extreme: if the particles are too large and HEAVY the bed will not fluidized well either, but tend to be very turbulent and form a spout." He goes on to present classification of fluidization by Geldart by use of the chart shown below. On this chart, the x-axis is the average particle diameter and the y-axis is the bulk density of the bed.

Mr. Alex C. Hoffmann of the Stratingh Institute for Chemistry and Chemical Engineering states: "Whether a material can be fluidized at all is the question: if it is fine or sticky, the bed will be cohesive. It will then tend to form channels through which the aeration gas will escape rather than being dispersed through the interstices supporting the particles. In the other extreme: if the particles are too large and heavy the bed will not fluidized well either, but tend to be very turbulent and form a spout." He goes on to present classification of fluidization by Geldart by use of the chart shown below. On this chart, the x-axis is the average particle diameter and the y-axis is the bulk density of the bed.

Sizing a PSV on your vessel is a matter of calculating how much heat is inputted from the fire. API-520 uses Q = FA0.82 where Q is BTU/hr, F is the insulation factor (commonly taken as 1.0 but can be less than 1.0 if your insulation will remain effective during the fire and not be dislodged by fire hoses) and finally, A is the external area in ft2. The vapor load is then the total heat input from the fire divided by the liquid's latent heat (BTU/lb).

As a fluid approaches its critical pressure, the latent heat as it boils decreases so the relieving flow rate increases. At the critical point, the latent heat goes to 0. Some companies simply use a minimum 50 BTU/lb latent heat others look at de-pressuring equipment, etc. One point is the protection, or potential lack of it, provided by a PSV during a fire. The BOILING liquid in the vessel from the fire helps keep the metal 'cool' so it retains its strength. Once the liquid is gone or the flame impinges on the wall not in contact with liquid, the metal can quickly reach a temperature where it has insufficient strength to withstand the internal pressure and you have a BLEVE. Not something, you want to be AROUND. As an added point to the information above, if 50 Btu/lb is not your company’s minimum standard for latent heat, here is an alternative to calculate the latent heat:

If you want to try and determine latent heat the most accurate thing WOULD be to take a process simulation tool such as PROII, HYSYS, winsim or the like. Set up a stream with the relevant COMPOSITION and pressure and make a bubble point calculation (=the program calculates the temperature where the liquid starts to boil at the PSV set point P+allowable overpressure). Then add a heater to the stream with a specified duty e.g. the RESULTING vapor stream and the duty that you specified can now be used to calculate the latent heat. Important: You have to specify a relatively low heat input because you want the latent heat for the first fraction that boils off

Sizing a PSV on your vessel is a matter of calculating how much heat is inputted from the fire. API-520 uses Q = FA0.82 where Q is BTU/hr, F is the insulation factor (commonly taken as 1.0 but can be less than 1.0 if your insulation will remain effective during the fire and not be dislodged by fire hoses) and finally, A is the external area in ft2. The vapor load is then the total heat input from the fire divided by the liquid's latent heat (BTU/lb).

As a fluid approaches its critical pressure, the latent heat as it boils decreases so the relieving flow rate increases. At the critical point, the latent heat goes to 0. Some companies simply use a minimum 50 BTU/lb latent heat others look at de-pressuring equipment, etc. One point is the protection, or potential lack of it, provided by a PSV during a fire. The boiling liquid in the vessel from the fire helps keep the metal 'cool' so it retains its strength. Once the liquid is gone or the flame impinges on the wall not in contact with liquid, the metal can quickly reach a temperature where it has insufficient strength to withstand the internal pressure and you have a BLEVE. Not something, you want to be around. As an added point to the information above, if 50 Btu/lb is not your company’s minimum standard for latent heat, here is an alternative to calculate the latent heat:

If you want to try and determine latent heat the most accurate thing would be to take a process simulation tool such as PROII, HYSYS, winsim or the like. Set up a stream with the relevant composition and pressure and make a bubble point calculation (=the program calculates the temperature where the liquid starts to boil at the PSV set point P+allowable overpressure). Then add a heater to the stream with a specified duty e.g. the resulting vapor stream and the duty that you specified can now be used to calculate the latent heat. Important: You have to specify a relatively low heat input because you want the latent heat for the first fraction that boils off

There is an AUSTRALIAN standard "AS1020 (1984) - Control of undesirable Static Electricity" In it, there is a table for flammable HYDROCARBONS as follows:

Pipe Size (mm) Max Velocity (m/s)

10 8

25 4.9

50 3.5

100 2.5

200 1.8

400 1.3

600+ 1.0

This is BASED on pure hydrocarbons, and there is a correction, which can be applied for fluids of DIFFERENT conductivity. Methanol has a higher polarity than hydrocarbons and hence is more conductive. The resistivity of diesel is 1013 ohm-m vs 108 for methanol. In addition to this, normal piping design guidelines should however be followed, such as APPROPRIATE earthing, and ensuring exit velocities into tanks of 1 m/s.

There is an Australian standard "AS1020 (1984) - Control of undesirable Static Electricity" In it, there is a table for flammable hydrocarbons as follows:

Pipe Size (mm) Max Velocity (m/s)

10 8

25 4.9

50 3.5

100 2.5

200 1.8

400 1.3

600+ 1.0

This is based on pure hydrocarbons, and there is a correction, which can be applied for fluids of different conductivity. Methanol has a higher polarity than hydrocarbons and hence is more conductive. The resistivity of diesel is 1013 ohm-m vs 108 for methanol. In addition to this, normal piping design guidelines should however be followed, such as appropriate earthing, and ensuring exit velocities into tanks of 1 m/s.

Pressure Vessel HANDBOOK Author = EUGENE F. Megyesy Publisher = Pressure Vessel Handbook Publ., Inc. P.O. Box 35365 Tulsa, OK 74153 Page 18 TELLS you how to calculate a pressure vessel's wall thickness; page 176 tells how to calculate an API Std. 650 Storage tank wall thickness. The rest of the book is a goldmine for young engineers - especially CHE's involved in vessel design. It also gives all the information you require for supports, nozzles, head design, piping, ladders, platforms, ETC.

Pressure Vessel Handbook Author = Eugene F. Megyesy Publisher = Pressure Vessel Handbook Publ., Inc. P.O. Box 35365 Tulsa, OK 74153 Page 18 tells you how to calculate a pressure vessel's wall thickness; page 176 tells how to calculate an API Std. 650 Storage tank wall thickness. The rest of the book is a goldmine for young engineers - especially CHE's involved in vessel design. It also gives all the information you require for supports, nozzles, head design, piping, ladders, platforms, etc.

Mr. Richard Lee of Plumlee International Consulting usually heat exchangers have two sets of test pressures per SIDE, ONE for strength tests, and the other for "operating" or "leak" tests. The strength tests are set by the design code and if you have the original design data sheets for your equipment then the information should be shown on these. If you do not then you will have to do the calculations yourself, the exact method will depend upon which design code you use, the most common one being TEMA (which uses the ANSI/ASME pressure vessel code for reference in this area).

Most shell and tube exchangers are designed such that each side of the unit will withstand the full design pressure, with only atmospheric pressure on the other side. In order to save money, some larger units will have the tube-sheets especially designed to withstand only a much lower differential pressure (REQUIRING both sides to be tested simultaneously). This important information should be shall quite clearly on the design sheets and on the vessel nameplate (assuming that either are available). If the only need is to check that a GASKET has been properly installed then it can be PERMISSIBLE to perform a lower pressure test based on the operating pressure. The acceptability of this lower pressure test will often depend upon the consequences of a leak.

Mr. Richard Lee of Plumlee International Consulting usually heat exchangers have two sets of test pressures per side, one for strength tests, and the other for "operating" or "leak" tests. The strength tests are set by the design code and if you have the original design data sheets for your equipment then the information should be shown on these. If you do not then you will have to do the calculations yourself, the exact method will depend upon which design code you use, the most common one being TEMA (which uses the ANSI/ASME pressure vessel code for reference in this area).

Most shell and tube exchangers are designed such that each side of the unit will withstand the full design pressure, with only atmospheric pressure on the other side. In order to save money, some larger units will have the tube-sheets especially designed to withstand only a much lower differential pressure (requiring both sides to be tested simultaneously). This important information should be shall quite clearly on the design sheets and on the vessel nameplate (assuming that either are available). If the only need is to check that a gasket has been properly installed then it can be permissible to perform a lower pressure test based on the operating pressure. The acceptability of this lower pressure test will often depend upon the consequences of a leak.

The FOLLOWING are items to consider when designing a piping system that will transport slurries:

1. Whenever possible, piping should be designed to be self-draining
2. Manual draining should be installed to drain sections of the piping when self-draining is not possible
3. Blow-out or rod-out connections should be provided to clear LINES in places where plugging is likely or could occur
4. ACCESS flanges should be provided at T-connections
5. Manifolds should have flanged rather than capped connections to allow for easy access
6. Clean-out connections should be provided on BOTH sides of main line valves so that flushing can TAKE place in either direction
7. BREAK flanges should be provided every 20 feet of horizontal pipe or after every two changes in direction

The following are items to consider when designing a piping system that will transport slurries: