Membrane per la separazione di CO2 e

reattori a membrana per il suo uso

A. Iulianelli, P. Morrone, A. Basile

ITM-CNR

Riace’s Bronze

As a result of the reorganization of the Italian Research National Council scientific network, the Institute for Membrane Technology (ITM-CNR) has been recently created.

The Headquarter and Administration of ITM are located in Rende

(CS) in the Campus of the University of Calabria, with a Section at the Padova University .

The Institute today has 29 units of permanent staff and about 35

temporary units constituted by visiting professors, researchers, Ph.D. students, post-doctoral fellowships, high-educational fellowships from national and international Institutions.

It is a multidisciplinary Institute based on backgrounds in

chemical engineering; process engineering; chemistry (organic and physical); biological science; food science; material science and physics.

Institute & Activity

ITM-CNR Institute on Membrane Technology

Inorganic membrane reactor

Membrane contactors

Water desalination by

membrane filtration

Gas separation: polymeric and

zeolite membranes

PEM fuel cell

Membrane bioreactor

A membrane is a permeable phase acting as a selective barrier.

Transport processes depend on a driving force (gradient of P, T, C, pH, etc.).

Polymeric dense membrane

(selectivity CO2/N2 > 50)

Inorganic dense membrane

(infinite selectivity H2/other

gases)

Transport processes depend on a driving force (as a gradient of P, T, C, pH, etc.).

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Membranes

Membrane

Organic

Inorganic

Wide availability of polymeric materials

Low cost

Wide surface area in small volumes (packing density)

Low mechanical resistance

Low maximum operating temperature

Low chemical stability in organic solvents

Wide range of operating temperature and pressure

Excellent chemical stability in organic solvents

Non biodegradable materials

Good mechanical properties

Some materials are brittle

Several materials and different structures

Higher costs

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Why polymeric membrane

Conceptual scheme of a membrane

module

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Biogas

• Biogas is generated by the activity of anaerobic bacteria.

• Biogas is comprised of about 60% of methane, 40% of carbon dioxide, and small amount of

hydrogen sulfide, nitrogen, and hydrogen.

• The heating value of biogas is about 60% of natural gas and about 25% of propane.

• Biogas has corrosive nature and storage of biogas is not practical.

Upgrading techniques

Chemical Adsorption

Pressure Swing Adsorption

Cryogenic Distillation

Membrane Separation

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Membrane Separation

Figura. Campione di membrana polimerica nanocomposita.

Immagine SEM della superficie ed ingrandimento a 5000X

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Robeson et al., Journal of Membrane Science 320 (2008) 390–400

1 Barrer = 3.348 x 10-16 mol m / (m2 s Pa)

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Figura. Schema celletta per prove di permeazione

mediante l’uso di membrane polimeriche nanocomposite

con filler inorganici di tipo TPO

Le condizioni sperimentali da utilizzarsi per l’esecuzione dei test di permeazione a gas puri e miscele sono nel seguito indicate :

T = ~ 25 °C;

DP transmembrana = 450 – 600 kPa;

Gas puri utilizzati = H2, CO2, N2, CH4;

Miscele di gas utilizzate = CO2/CH4 in rapporto molare 30/70, 40/60, 50/50.

Selettività ideale a = (QCO2/Qi)p Fattore di separazione SF = (xCO2/xCH4)p/(xCO2/xCH4)r

Membrane module scheme

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A case study

Flusso permeante attraverso la membrana in funzione della

pressione trans-membrana a 20 °C in due diversi cicli di

prove; campione di membrana TPO20

ΔP [bar] α(CO2 /CH4)

5 11

5,5 12

6 11

ΔP [bar] α (CO2 /CH4)

4,5 13

5 12

5,5 11

6 10

Selettività ideale (CO2/CH4) in funzione della pressione

trans-membrana per membrane TPO20 nel 1° ciclo di testing Selettività ideale (CO2/CH4) in funzione della pressione

trans-membrana per membrane TPO20 nel 2° ciclo di testing

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A case study

Fattore di separazione vs concentrazione di CO2 per membrane

polimeriche di tipo TPO20

Fattore di separazione CO2/CH4 per un campione di

membrana TPO20 in funzione dei tempi di lavaggio

N° PROVA DETTAGLIO PROVA

1 Membrana esposta a corrente di CO2 pura – lavata con N2

per 5min – esposta a miscela di CO2/CH4 30/70

Acquisizione: dopo 15 min

2 Membrana esposta a miscele CO2/CH4

- 30/70 - 40/60 - 50/50 senza alcun lavaggio intermedio

e successivamente esposta a miscela CO2/CH4 30/70

Acquisizione dati dopo 45 min di permeazione

3 Membrana lavata per 1 h con N2 e successivamente

esposta a miscela CO2/CH4 30/70

Acquisizione dati dopo 30 min di permeazione

4 Membrana lavata per 4h con N2 ed esposta a miscela

CO2/CH4 30/70

Acquisizione dati dopo 30 min di permeazione.

Material CO2/N2

selectivit

y

CO2

permeance

(m3·m-2·Pa-1·s-

1)

Polydimethylsiloxane 11.4 3200 (*)

Polydimethylphenilene oxide 19 2750

Poly(4-vinylpyridine)/polyetherimide 20 52

Polyethersulfone 25 665

Polyacrylonitrile with ethylene glycol 28 91

Polysulfone 31 450

Polyimide 43 735

Poly(ethylene oxide) 52 52

Poly(amide-6-b-ethylene oxide) 61 608

Polyvinyl alcohol (cross linked) 170 8278 (*)

Vinyl alcohol / acrylate copolymer - FT 1417 2400 (*)

Polyvinyl alcohol (cross linked

formaldehyde)

1782 338 (*)

Large scale membrane technology already exists!

www.watertechnology.

net/projects/

israel/israel10.html

Ashkelon, Israel, SWRO

plant

Number of membrane

elements:

40000

Final capacity:

100 million m³ / year

Photograph of a

hydrochloric acid

electrolysis plant, 215.000

kton Cl2/year, Caojing –

Shanghai.

Pierre Millet - Chapter 28:

“Chlor alkali

membrane/process

technology”, in A. Basile

(Ed.) Handbook of

Membrane Reactors. Vol. 2

– Industrial applications and

economics.

Treatment 32 RO trains on 4 floors; 40,000

membrane elements

Water price $0.527/m³

Plant footprint 75,000m² (300m x 250m)

Maximum nominal

electrical consumption <4kWh per m³ product water

Feed water salinity 40,750ppm TDS

Product water salinity <40ppm TDS

Salinity reduction 99.9%

Boron reduction >92%

330,000 m3/d

boron < 0.3

mg/L

Ashkelon,

Israel

FILMTEC are the RO membrane elements

utilized at one of the largest seawater desalination

plants: Ashkelon Desalination Plant (SW30HRLE-

400).

El Paso Desalination Plant, Texas: the site of the world's largest

inland desalination plant (104,000 m3/d)

Deep-well injection was selected as the

preferred method of concentrate disposal.

The concentrate is placed in porous,

underground rock through wells. The sites

would confine the concentrate to prevent

migration to fresh water, provide storage

volume sufficient for 50 years of operation

and meet all the requirements of the Texas

Commission on Environmental Quality.

It uses RO to produce drinking water by

treating previously unusable brackish

groundwater (recovery factor ≈ 83%).

Production costs for the water: less than

0.36$/m3.

View of RO membrane units from inside the desalination

plant

Source: http://www.epwu.org/167080115.html

The current global installed desalination capacity is 62.8 million m3/d.

Membrane based systems are the most widely used processes: 80% of all desalination

facilities (around 15,000) and ca. 50% of the total capacity of desalination plants.

Reverse

Osmosis

(RO)

90%

Electro

Dialysis

Reversal

(EDR)

10%

Source: V. Frenkel, Desalination & Water Reuse 17

(2008) 47.

Membrane

Desalination

80%

Thermal

Desalination

20%

Multi Effect

Distillation

(MED)

25% Multi Stage

Flash (MSF)

45%Vapor

Compression

(VC)

30%

W.J. Koros, Journal of Membrane Science, 300 (2007) 1:

An optimized thermal distillation plant producing 100 million gallons per day

requires 73 kw hr/m3. A seawater RO system (with an energy consumption of only 2.2 (kw hr)/m3) is over 10 fold more efficient than the thermal approach.

Desalination of brackish and sea waters by Membrane Reverse Osmosis:

the major industrial success of membrane operations in the last years

Photograph of a Permea Hydrogen recovery

unit installed at an ammonia plat. The hollow

fiber modules are mounted vertically.

[R. W. Baker, “Membrane Gas-Separations”,

in “Membrane Separations”, E. Drioli (Ed.),

Wiley-VCN, 2009]

Photograph of the 550-million scfd CO2 removal plant installed by UOP at

Kandanwari (Pakistan).

The UOP Separex system reduces CO2 content of a natural-gas stream from

6.5 to 2% CO2.

[R. W. Baker, “Membrane Gas-Separations”, in “Membrane Separations”, E.

Drioli (Ed.), Wiley-VCN, 2009]

Photograph of a system installed by MTR in Qatar in 2007,one of the most successful

petrochemical applications: treatment of resin-degassing vent in a polyolefin plant.

The plant uses hydrocarbon-permeable membranes to recover unreacted monomers from

a polyolefin plant resin degassing unit. [R. W. Baker, “Membrane Gas-Separations”,

in “Membrane Separations”, E. Drioli (Ed.), Wiley-VCN, 2009]

ITM-CNR