2151636
Description
Flashcards by Amirah Hill, updated more than 1 year ago
|
Created by Amirah Hill
about 9 years ago
|
|
| Question | Answer |
| Batch Process | The feed (charge) enters the tank all at once. Once the reaction is complete, the product is removed all at once. |
| Continuous process | feed is always flowing in with a high amount of reactant and effluent is always coming out with a high concentration of product. (Product is constantly withdrawn from the rxtr) |
| Semi-batch process | Not continuous nor batch ex. One reactant is added to a vessel and then later, another one is slowly added. |
| Steady-State | A continuous process where process variables like: -flow rate -temperature -pressure, etc... operate at nominally (by name) consistent values |
| Transient (Unsteady-state) | A process with changing process variables. By nature, semi-batch and batch processes are transient while continuous processes could be either or. |
| General Balance equation | Input - Output + Generation - Consumption = Accumulation |
| Gen. Balance Eqn for Non-reactive system | There's no generation or consumption in a non-reactive system so: Input - Output = Accumulation |
| General Balance eqn for reactive processes | Generation and Consumption depend on the balance at hand. If balance is on a total mass or atomic species, there is no generation or consumption since mass is neither created nor destroyed. |
| Flowchart | Using boxes and other symbols to represent process units and lined with arrows to represent input and output. |
| Scaling | Masses and NOT mass fractions of all streams can be multiplied by a common factor and the process would remain balanced. *scaling up/ scaling down |
| Basis of Calculation | An amount (in either mass or moles) of flow rate of one stream or stream component in a process. Usually use 1 or 100. |
| Degrees of Freedom | DOF<0 underspecified and not solvable DOF=0 solution is possible DOF>0 overspecified and not solvable |
| DOF for non-reactive process | +unknowns -material balances (species) -relationships *For multiple units, ensquare each subsystem and do a DOF analysis |
| Raffinate | The phase rich in the diluent (water for example) |
| Extract | Phase rich in the solvent. |
| Stoichiometric Proportion | The ratio of two reactants A and B in a balanced eqn. |
| Limiting reactant | A reactant is limiting is it is present in less than its stoichiometric proportion relative to every other reactant. |
| Fractional Excess | For percentage excess, multiply by 100. |
| Fractional Conversion | |
| Yield | |
| Selectivity | |
| DOF for Reactive Molecular species balance | +No. unknown labeled variables +No. independent chem reactions (cannot mult./add one eqn to get the other) -No. independent molecular species -No.relationships |
| DOF for Atomic species balance | +No. identified/labeled unknowns - No. independent atomic species -No. non-reactive species -No. other relationships |
| DOF for extent of reaction | +No. labeled unknowns +No. independent chemical rxns -No. independent reactive species -No.independent non-reactive species -No. other relationships |
| Combustion | Rxn of a fuel with oxygen to produce CO2 and H2O |
| Partial/Incomplete Combustion | A combustion reaction where CO is formed from a hydrocarbon. |
| Composition on a Wet Basis | Component moles fractions of a gas that contains water. |
| Composition on a dry basis | The component mole fractions of a gas without water. |
| Stack gas / Flue gas | Product gas that leaves a combustion furnace |
| Theoretical Oxygen | Amount of oxygen produced based on the balanced equation |
| Percent excess air | Trick: If 50% excess, then 1.5 (moles air)theo |
| Excess air | The amount of air fed to the reactor that exceeds the theoretical air. |
| Molecular Weight ( MW ) of air | 29.00 (kg air/kmol, lbm air/lb-mole, etc...) |
| Composition of Air | 0.21 mol O2/mol air 0.79 mol N2/mol air |
Want to create your own Flashcards for free with GoConqr? Learn more.