Membrane technology



MEMBRANE TECHNOLOGY

A small size membrane bipolar electrolyzer ELM 0.4 has been conceived, designed and manufactured  in order to provide customers with a reliable ,highly efficient and flexible device suitable to produce” on site “small (and also very small) quantities of chlorine , caustic soda and hydrogen to be directly converted ,if needed, to bulk sodium hypochlorite solution(“bleach”) or to hydrochloric acid solution ,or used for any other required application.

Why bipolar ? Because the bipolar arrangement , due to the assembly of many elementary cells in the same stack, results in a lower cost of the hardware , lower power consumption ,lower plant area allowing a easy modulation of the electrolyzer output through the number of elementary cells assembled in one stack.

membrana

FEATURES OF ELM 0.4 Modular Bipolar Electrolyzer
A. Characteristics  
Type bipolar modular
Dimensions 0.4 m2 active surface
B. Hardware  
Anode electrode Titanium (DSA coating)
Cathode electrode Nickel (not coated ; coating upon request)
( Stainless steel :optional)
C. Design operating data  
Current density 4 KA / m2   (operating)
5 KA / m2 (design)
Temperature 80° C
Pressure slight vacuum up to  0.35 Kg/cm2 g
NaOH 32% membrane grade solution
(Fe less than 0.5 ppm)
Power consumption at 4 KA/m2
(80°C , NaOH 32%)
2,355  Kwh / T NaOH  at cell terminals

Simplicity and Reliability
The ELM 0.4 electrolyzer is supplied assembled in standard modules “ChlorPlus unit” whose output are chlorine, membrane grade 32%caustic soda and hydrogen.

1. One module daily production (Kg)
Chlorine 500 -1500
NaOH 100% 564 - 1680
Hydrogen 14 - 42
Lower or slightly higher productions are obtained playing on the number of elementary cells in the stack

2. One module main raw materials consumption per Metric Ton NaOH 100%
Salt (Vacuum salt 99.9 % NaCl) 1.5 ton
Demiwater 630 liters
NaOH (100% basis) 60 Kg
HCl (100% basis) 90 Kg

3. Characteristics and maximum output of “ChlorPlus “Modularized Units


Item

Modules

Rectifier

Stacks

MTPD(max.)

 

Elettrolizzatori

raddrizzatore

supporti

Cl2

NaOH 32%

ChlorPlus 500

One

one

one

0.5

1.76

ChlorPlus 1000

Two

one

one

1.0

3.52

ChlorPlus 1500

Three

one

one

1.5

5,28

ChlorPlus 3000

Three x 2

two

two

3.0

10.56


Production capacities beyond 3 MTPD Cl2 may require the adoption of the larger
electrode electrolyzers. Please consult PFI ‘s commercial department.
* Each module is equipped with its own rectifier rated 1500A-150V . Depending upon
the customer’s requirements concerning the maximum circuit voltage two or three
modules can be arranged in series to get 1 or 3 TPD Cl2 and fed from a single rectifier (a
spare can be also provided) rated 1500A-150V.

4. Maximum output of sodium hypochlorite from Chlorplus Units (litres per day) Chlorplus (litri/giorno)


item

Conc.= 125 g/l av.chlorine

Conc.= 150 g/l av.chlorine

ChlorPlus 500

4000

3,300

ChlorPlus 1000

8000

6,600

ChlorPlus 1500

12,000

9,900

ChlorPlus 3000

24,000

19,800


Depending upon how the above products are combined one with the other the plant output is:
- 100- 150 gpl available chlorine sodium hypochlorite solution.
- 32 % hydrochloric acid solution.
- 32 % NaOH solution.

Cell Room Configuration
The availability on site of such products eliminates the risks associated with their transportation and storage especially in countries with high ambient temperature . The uses of above products are well known:

a. Sodium hypochlorite solutions
- drinking, waste water and swimming pool disinfectionmembrana
- tower cooling water disinfection
- pulp and paper

b. 32 % hydrochloric acid solution
- any use in chemical plants , municipalities and industries.
(pH adjustment, cleaning, water treatment, etc..)



c. 32 % caustic soda solution
- any use in chemical plants ,municipalities and industries

d. Ferric chloride
- an important flocculant widely used for water treatment

Due to the design characteristics of the ELM 0.4 electrolyzer, resulting in an extremely
simple arrangement of the modules in the cell room, any production requirement can
be easily matched. (the picture shows a ChlorPlus 1500 unit with two modules expansible up to three)

Copyright © 2011 • P.F.I. impianti • All rights reserved