Principles of Chemical Processes - Mass & Energy Balance

Define pressure and explore fluid and hydrostatic pressures, including atmospheric, absolute, and gauge pressures. Learn to measure fluid pressure and express it as a fluid head using density and height.

Explore pressure scales, including absolute, gauge, vacuum, and atmospheric pressure, and learn how gauges, zero reference, calibration, and conversions define pressure measurements and standard units.

Use dimensioned analysis and conversion charts to convert pressures between absolute and gauge forms across units such as atmospheres, inches of mercury, millimeters of mercury, and kilopascals.

Explore fluid pressure measurement using elastic-element methods, including bourdon tube gauges and diaphragms, and learn how open-ended, differential, and sealed manometers determine pressure differences with fluid columns.

Analyze a differential manometer to determine the pressure drop between points one and two using water density, Manami fluid density, and height differences.

Explore the ideal gas equation and equation of state, with standard temperature and pressure, and molar volume, including deviations from ideality. Solve two-state gas problems to compute volumes and flow.

Explore ideal gas mixtures and apply Alden's law to relate partial pressures to total pressure via mole fractions, and analyze vapor–liquid equilibria for multi-component systems.

Explore Henry's law for dilute gas dissolution, Raoult's law for vapor pressures in mixtures, and the Antoine equation for temperature-dependent vapor pressure.

identify mass balance principles by applying conservation of mass to batch, continuous, and semi-batch processes, and distinguish steady and unsteady states with the general balance equation.

Differential balances describe instantaneous changes in continuous processes. Integral balances apply to batch processes; the lecture links steady-state input equals output to a benzene distillation example.

Explore integral and total mass balances in batch and mixing processes, applying steady-state and no-reaction assumptions to compute benzene and methanol–water compositions.

This lecture applies integral balances to a semi batch hexane vaporization problem, using air and hexane balances to estimate the time to vaporize 10 m^3, about 6080 minutes.

Explore differential processes for material balance—absorption, stripping, extraction, and leaching—using flowcharts and unit operations to set up and solve material balance calculations.

Draw a flowchart of an evaporation chamber fed by three streams, convert volumetric water flow to molar rate, and solve for unknowns with a nonreactive steady-state mass balance.

Learn how to scale a flowchart for chemical processes using a proportional factor, preserving mass balance and stream compositions, while selecting a basis of calculation.

Balance mass and components to dilute a 20% NaOH solution to 8% using water, with a 100 kg basis. Determine water and product flow to achieve the target concentration.

Explore balances for reactive systems, introducing generation and consumption terms, stoichiometric coefficients, and how to use stoichiometry to relate molar flows and product yields.

Identify limiting and excess reactants from stoichiometry, compute fractional conversion, and apply extent of reaction in a batch reactor, using acetylene and hydrogen to produce ethane.

Learn to calculate the extent of reaction from feed moles and fractional conversion, apply sign conventions for reactants and products, and determine outlet compositions in a reactor from ammonia synthesis.

Identify the limiting reactant among propylene, ammonia, and oxygen on a 100-unit feed basis, apply 30% conversion, and calculate excess reactants and outlet molar amounts.

Explore how multiple reactions shape yield and selectivity, define extent of reaction, and assess side reactions and economic loss in chemical processes.

Apply mass balance and extent-of-reaction analysis to a multi-reaction dehydrogenation reactor, calculate outlet molar compositions of ethylene, hydrogen, methane, and inert gas, and determine selectivity of ethylene to methane.

Apply molecular and atomic species balances to a steady-state hydrogenation example, solving for unknowns via molecular balances, atomic balances, or extent of reaction, with degrees of freedom analysis.

Explore degree-of-freedom analysis for reactive balances and solve methane-air combustion using molecular and atomic balances and extent of reaction to determine the product molar composition.

Explore energy balance through kinetic, potential, and internal energy forms, applying the first law to closed and open systems, with mass flow and velocity calculations.

Apply energy balances on closed systems to calculate potential energy changes and relate heat and work transfers, distinguishing open and closed systems by accumulation concepts from the first law.

Master energy balances for open systems at steady state, accounting for mass crossing boundaries, flow work and shaft work, and using specific properties and enthalpy concepts.

Apply open-system energy balance to a turbine: relate mass flow, shaft work, and kinetic and potential energy changes to compute the specific enthalpy change.