0
Chemical Engineering
Chemical Engineering is the branch of engineering that deals with the technology of large-scale chemical production and the manufacture of products through chemical processes. Today, the field of chemical engineering is a diverse one, covering areas from biotechnology and nanotechnology to mineral processing.
1,464 Questions
Advantages of the Miller cycle engine?
The Miller Cycle engine has a very flat torque curve, with maximum torque achieved at 3500 rpm, as compared to Otto Cycle (standard 4-stroke) engines which generally require 4500 rpm or higher.
Due to this lower-end torque ability, the Miller Cycle engine is capable of moving much heavier loads at a much lower fuel economy.
What are the two main causes of corrosion in rig?
A number of commercially available SiC and Si3N4 materials were exposed to 1000°C for 40 h in a high-velocity, pressurized burner rig as a simulation of an aircraft turbine environment. Na impurities (2 ppm) added to the burner flame resulted in molten Na2SO4 deposition, attack of the SiC and Si3N4, and formation of substantial Na2O. x(SiO2) corrosion product. Room-temperature strength of the materials decreased as a result of the formation of corrosion pits in SiC and grain-boundary dissolution and pitting in Si3N4.
How do you convert volume to mass?
you need to know the density (mass per volume) of the stuff to be converted,
then it's density divided by mass.
Cycle of concentration in cooling tower?
Cooling Tower Cycles of Concentration As pure water is evaporated, minerals are left behind in the recirculating water. As evaporation continues, the water becomes more concentrated than the original make up water. This eventually can lead to saturated conditions. The term cycles of concentration compares the level of solids of the recirculating cooling tower to the level of solids of the original raw make up water. If the circulating water has four times the solids concentration than that of the make up water, then the cycles are 4. Bleed off is the process of removing a portion of concentrated recirculating water, which is obviously replaced with fresh make up water. By specifying a certain amount of bleed off we limit the cycles of concentration the system can operate at, thus controlling scale formation. Various treatments will let us operate at various cycles depending on the make up water analysis and heat loading of the tower. Bleed off is critical to a successful treatment program. The preferred method of bleed off control is with the use of automated bleed off control. This includes a contacting head water meter, dual timer, chemical pump and solenoid controlled bleed off line. A) Evaporation Loss: from a cooling tower (E) = .001 (Cr) (DT) where Cr = circulation rate in gallons per minute and D T = temperature differential between hot and cold water in °F. The evaporation rate amounts to 1% of the recirculation rate for every 10°F DT. B) Windage Loss: This is a relatively small amount of entrained water lost as fine droplets in the air discharge from a tower. Unlike evaporation which does not contain dissolved impurities windage carries these impurities with it and reduces dissolved solids in the circulating water. Typical values are 0.1% to 0.3% of the circulating rate for mechanical draft towers. C) Bleed off: In the evaporation process the non volatile impurities in the make up water are concentrated. To prevent excessive concentration some of the circulating water must be removed from the system. This is commonly referred to as bleed off or blowdown. The amount of bleed off can be determined from the following equations: % B (bleed off) + % (windage) = % E (evaporation loss) / ( cycles -1) D) Cycles: The previous equation added a new turn to the mix . CYCLES!!!!!!!! This is one of the most difficult terms to understand. I will now attempt to define cycles of concentration. The NACE defines it as: A measure of the degree to which dissolved solids are being concentrated in the circulating water. It is in effect the inverse of blowdown. As pure water is evaporated all of the solids are left behind so they concentrate in the cooling tower water. If we start out with fresh water the tower has one cycle of concentration. When all the fresh water is evaporated ( solids are still in the tower) the tower then refills itself with more fresh water and we have twice the solids in the tower. We now have two cycles of concentration. This process will proceed and scale will form at a certain point. We use bleed off to prevent the tower from reaching the point of scale formation. In an actual tower, this is an ongoing process with continuous addition of make up water and continuous bleed off. The allowable cycles of concentration will be determined by the laboratory. They are based on water analysis, heat transfer rate of the equipment, and feed equipment present. We normally use chloride to determine the number of cycles a tower is operating at. The following equation can be used for this calculation: Chlorides in tower water / Chlorides in make up water = Cycles of concentration For example, a tower operating at a 450 gallons per minute recirculating rate (Cr) , 5 cycles of concentration, 10° DT, and 0.1% windage loss: %B + .1% = 1% / (5-1) which is %B = .25% - .1% therefore %B = .15% of the circulating rate. %B = 0.15% ( 450 gallons/minute) which is 0.675 gallons of bleed off /minute. Total make up water requirements for the system are: Bleed off 0.675 gallons per minute
Evaporation 1% (450 gallons/minute) = 4.5 gallons/minute Windage 0.1% (450 gallons/minute) =.45 gallons/minute Total make up water = 5.625 gallons/minute Total make up water per hour is = 60 minutes/hr. ( 5.625 gallons per minute) = 337.5 gallons per hour. As you can see the higher the cycles the less make up water and blowdown are required. This is true to a certain point where additional cycles do not decrease the amount of make up water and blowdown as drastically. The following graph illustrates the point. As you can see at about 4.5 cycles the curve starts leveling off which indicates higher cycles will not effect the quantity of make up water drastically.
How will you get registration for pwd pune?
Pls go on pwd site gt into Pune PWD building address,personally meet
How can one control the process factors in order to get less maintenance?
make the proper lubrication schedule of all rotating equipment and availability's of all spare parts at proper time.
What is the best liquid trimethylindium source for mocvd since solution-TMI is really a suspension?
DIPMeIn or Di-isopropylmethylindium, a novel and safer liquid alternative to solid trimethyl indium, developed to gain the advantage of high throughput deposition of Indium phosphide (InP) based semiconductors and Copper-Indium-Gallium-Selenide (CIGS) based Solar Cells. (from Definitions database, http://www.definition-of.com/DIPMeIn)
What is a tall fractionating column?
A tall fractionating column has 2 main parts 1- tall :usualy mean high pressure 2-fractionating column: means sepration of a componant usualy you will find something like propane fractionation means removing propane I hope I have cleared some of the meaning
Why low temperature boiling liquid store in high pressure spherical tanks?
Spherical tanks distribute the vapor pressure from within the tank equally to the inner surface of the tank.
If one were to make a tank a cube or a cylinder, you would have to use a lot more metal to create a tank strong enough to hold the same amount of boiling liquid.
Dams are built in a curved manner (check images of the Hoover Dam) along the same principles- to distribute pressure evenly to a curved surface- rather than making it straight.
What is clinker cooler offset?
Clinker cooler offset refers to the difference in temperature between the hot clinker exiting the cooler and the ambient temperature or the desired operational temperature. This offset is crucial for optimizing the cooling process in cement production, as it affects energy efficiency and the quality of the final product. A proper clinker cooler offset ensures that heat recovery systems operate effectively, reducing energy consumption and minimizing environmental impact. Maintaining the right offset is essential for maximizing throughput and maintaining equipment longevity.
How can you find the amount SO4 in CaSO4.2H2O?
To find the amount of sulfate (SO4) in calcium sulfate dihydrate (CaSO4·2H2O), first determine the molar mass of the compound. The molar mass of CaSO4·2H2O is approximately 172.17 g/mol, with the sulfate ion (SO4) contributing about 96.06 g/mol. To find the mass percentage of SO4 in CaSO4·2H2O, divide the molar mass of SO4 by the molar mass of the entire compound and multiply by 100. This will give you the proportion of SO4 in the hydrate.
What is the different between furnace and heater?
Good question.
A furnace is a enclosure in which energy in non thermal form (e.g. a fuel) is converted into heat. The inside of the enclosure becomes an intensely hot place.
A heater is an apparatus that heats or provides heat.
In refineries, the terms "furnace" and "heater" are used interchangeably, sometimes with the word "fired" in front of heater.
There is no such thing as styrofor. Assuming you mean styropor, this is another name for a material known as polystyrene.
What is the environmental impact of injection moulding?
Injection moulding can have several environmental impacts, primarily due to the use of plastics and energy consumption. The production of plastic materials often involves fossil fuels, contributing to greenhouse gas emissions and resource depletion. Additionally, the process generates waste, including defective parts and scrap material, which can contribute to landfill issues if not properly recycled. However, advancements in recycling technologies and the use of biodegradable materials are helping to mitigate some of these negative effects.
What does stripping section do in distillation column?
The stripping section of a distillation column is designed to remove lighter components from a liquid mixture, typically by applying heat and allowing vaporization. As the liquid descends through this section, it encounters rising vapor, which facilitates mass transfer between the phases. This process enhances the separation of components by concentrating heavier fractions at the bottom and allowing lighter fractions to ascend towards the top. Ultimately, the stripping section improves the overall efficiency and purity of the distillate.
I'm not aware of a material named "Delron", but there is a material called "Delrin" which is a brand name for an acetal polyoxymethylene resin owned by DuPont. It is a hard resin approved for food handling use by the FDA. It is an economical material with properties of good strength, light weight, and self-lubrication. It is commonly used in the food industry, toys and in paint-ball markers. Grades with higher toughness and strength are used in ski-bindings, gears, and many other applications; typically those which require moderate strength and low-friction.
Why does corrosion rate of no value on localized corrosion?
in my opinion, the value of corrosion rate obtained from certain reading is generally determine general corrosion rate, regardless what type of corrosion occur on a specific surface.
in localized corrosion, where only some spots on surface is exposed to corrosion and other may be covered by film and etc. From my time of study, still didn't fine any research that can determine corrosion rate of localized corrosion unless u have a really micro- instrumentation that can monitor corrosion on the localized spots..
Izzudin
saujana2@gmail.com
How do you enhance rate of reaction in CSTR?
rate of a reaction can be increased by increasing the temperature if the reactor
