seps

types of separations

extraction, evaporation, distillation, membrane separation

mechanisms of separation

phase creation, phase addition, solid agent, barrier, force field

factors that influence feasibility of separation operations

feed conditions, product conditions, property differences we can use, characteristics of separation operation

important concepts in separation operations regime

yield, selectivity

flux definition

transfer rate/ transfer area = permeability/ thickness* driving force

asymetric membrane

thin skin for separation + porous support layer

types of membranes

rubbery, glassy, ion exchange

components in the design of a membrane

• thin active layer

• high/low permeability for a and b

• stable and strong membrane

• long life

• large surface area, small volume

• can control concentration polarization

• easy to clean

• low cost

types of flat membrane geometries

stirred cells, plate-and-frame, spiral-wounds systems

types of tubular membrane geometries

cylindrical, hollow fiber system

specs of a hollow fiber system

4.5×10^6 fibers in a 25.4 cm D cartridge

area/volume ratio = 5000 ft2/ft3

osmosis

liquid separation via nonporous membrane

reverse osmosis

liquid separation via nonporous membrane w pressure gradient

dialysis

liquid separation via porous membrane w pressure gradient

microfiltration

liquid separation via microporous membrane w pressure gradient

ultrafiltration

liquid separation via microporous membrane w pressure gradient

pervaporation

liquid separation via nonporous membrane w pressure gradient

gas permeation

vapor separation via nonporous membrane w pressure gradient

liquid membrane

vapor/liquid separation via nonporous membrane w pressure gradient

MF, UF, NF, RO trends

• pore size gets smaller

• less molecules allowed

• operating pressure increases

• osmotic pressure increases

polarization coefficient

M= Cw/Cb

J solvent

= ksolvent/tm( delta P - delta pi)

gelification theory

high concentration polarization at the membrane surface will form a gel-like layer because it surpasses solubility limit. causes limiting flux

membrane resistance in gelification theory

tm/ksolvent = constant

gel resistance in gelification theory

tg/kg is variable

plant capacity of milk and dairy

5000 L/hr skim milk or 160 m3/day of milk

plant capacity of pharmaceutical industry

40.3E6 tablets/year

acetylsalicylic acid: 5500 tons/yr

capacity of co2 capture plants

texas: 62 MW, 16 ton co2/year with EOR

norway: 52 MW, 74000 tons co2/year of storage

japan: 50 MW, 3650 tons co2/year of crop cultivation

capacity of ion exchange plant

pfas treatment: 17200 m3/day

uranium removal: 363 m3/day

capacity of adsorption technology plant

sludge-based: 10400 m3/day

phosphorous recovery: 10 m3/day