POLY ALUMINIUM CHLORIDE process card 103 - 1/2 1 - The products PAC 18% and PAC 9 HB

PAC is a flocculant of new concept, the specific properties of which derive from the action of its basic active constituent, namely Poly Aluminium Chloride. This is a polynuclear complex of polymerised hydro-aluminium ions, having the following general formula:

{ Al2 (OH)n Cl 6-n }x

PAC is supplied in the form of aqueous solution which facilitates the transport and storage operations and subsequent dosage of the reagent. Two types of solutions are supplied, corresponding to: - PAC 18, containing 17,5 0,5% Al2O3, specific for waste waters and neutral

sizing in paper making. It is used as primary coagulant aid for any clarifying/flocculation process relating to the treatment of surface or underground water and urban or industrial effluents

- PAC 9 HB, containing 9 0,5% Al2O3, specific for potable waters.

2 - Production methods The PAC 18% production process lies in the batch etching reaction of alumina with an acqueous solution of hydrochloric acid. The reaction takes place in a glass lined reactor equipped with agitator. During reaction the temperature is controlled and at end of reaction the product is discharged into an holding tank. The discharged product is maintained in agitation and non reacted alumina and insolubles are separated by filtration. A venting system assures the collection of vent discharges for storage tanks and safety valves. The liquid effluents, mainly acid waters, are collected into a holding tank from which they are recycled to the production plant. Using sulphuric acid instead of hydrochloric acid Aluminium sulphate solution can be produced with the same process. The PAC 9 HB, production process is obtained by reaction of PAC 18% with aluminum sulphate and a basifier, using a GFRP reactor and a mixer-mill of particular design. The reaction is carried out at room conditions and production filtration is not required.

3 - Quality The basic product from the plant will be according the following specifications. Specifications PAC 18% Aluminium PAC 9 HB Sulphate (8%) - Appearance - clear liquid liquid clear liquid - Density at 20C kg/dm3 1,35 - 1,20 - Viscosity at 20C Cst 21,6 - 10-20 - Freezing point C -20 - - - pH at 20C N 0,8 1,2 - 2 3 - Al2O3 content % 18 8 9 - Al2O3/Cl ratio max 3,3 3,5 - -

Formulations, according to end use requirements, will be obtained by blending the basic product with other formula components.

___________________________________________________________________________________________ CONSITO S.r.l.-Piazza IV Novembre, 1-20124 Milano (Italy)-Tel. 02-66981651 - Fax 02-66984739 e-mail: consito@consito.it

POLY ALUMINIUM CHLORIDE process card 103 - 2/2 4 - Consumptions - Referred to one m. ton of finished product

Feedstock PAC 18% Aluminium PAC 9 HB & utilities sulphate (8%) - Alumina (Al2O3-58/62%) kg 300 325 145 - - Hydrochloric acid (3133%) kg 680 700 - - - Sulphuric acid (98%) kg - 242 - - PAC 18% kg - - 460 - Alum 8% kg - - 75 - Basifier 100% kg - - 15 - Steam (7 bar) kg 250 170 - - Cooling water m3 15 16 - - Electric power kwh 35 38 15 - Compressed air Nm3 16 16 10

5 - Investment - U.S. Dollars : (quoted on request) - Required area (m. 50x50) : m2 2500 - Type of process : BATCH - Capacity PAC 18% sol : t/yr 25.000 - Operation (24 hr/day) : 330 days/yr

6 - Use pattern Water treatment - The poly aluminium chloride (PAC) is used for settling of solid particles present into drinkable waters and for the flocculation of civil and industrial effluents. It has also a high antibactericide effect, due to the presence of chlorine into the product formula, and can be utilized for large range of pH and with higher turbidity. Paper manufacture - The main features of PAC are its high Al2O3 content and polymeric nature, which give rise to products of hydrolysis characterized by a high molecular weight and a large number of positive electric charges able to interact with the cellulose fibres and size, optimizing the sizing phase and the retention of fibres.

7 - Basicity - Simple dilution of PAC 18% allows to obtain a PAC 10% solution showing a basicity up to 40%. By blending some components to PAC 18% it is possible to produce PAC 9% H.B. a solution with a basicity of 64 68% without formation of solid residues as common for other commercial processes which require a filtration. The stability to storage is very good and PH range is 2 3. PAC 9 HB is recommended for treatment of potable waters whilst PAC 18% is used for waste waters of civil and industrial effluents.