El M

anan

tial

NR. 52SEPTEMBER2012

CERTIFIED PROFESSIONAL IN DESALINATION

PROFESSIONAL CERTIFICATE IN “ASSEMBLY, OPERATION AND MAINTENANCE OF REVERSE OSMOSIS DESALINATION PLANTS”

It is an accepted fact that in arid and semi-arid regions desalination is increasingly a guarantee for the supply of water to the population, industry and agriculture.The process of reverse osmosis (RO) desalination has evolved considerably in recent years and consequently, energy consumption and production costs have been substantially reduced.Therefore, desalinated water demand is expected to continue to grow at a steady pace.Accordingly, reverse osmosis desalination plants acquire an

increasing role in the GDP of some societies.In the Canary Islands for example, over 50% of GDP is now generated thanks to desalinated water.In the Spanish Mediterranean coast and the Balearics, this dependence is still less, but growing demand for water, accompanied by the entry into operation of a number of new desalination plants, suggest the importance of desalinated water in these regions will increase.Outside Spain and in other Mediterranean countries, as well as in virtually all arid countries, there is also a growing interest in desalination.The demand for skilled personnel is therefore also growing.

SECTOR INTEREST

The assembly, operation and maintenance of RO desalination plants require specific knowledge: hydraulic, mechanical and electrical, as well as chemical and biological, in addition to health and safety related to industrial plants.It appears, the special know how required in RO desalination is not part of any oficial professional certificate in Spain or Europe.Currently, workers gain their technical knowhow in assembly, operation and maintenance of RO desalination plants by training internally in the desalination plants, and after they have been hired.This creates two problems in the labor market since, on one hand,

Reverse osmosis desalination plant Aicante II

SOCIAL PROGRAM 2012/2014

THE DRINTEC™ REMINERALIZATION PROCESS, NOW IN CONTAINERSA new design of DrinTec ™ remineralization units in container format has been developed by the FCCA for spaces with low rise and thanks to collaboration with the Australian company Chatoyer Water (Perth) and the Spanish company Ursa, S.L. (Orio)From an initial idea, based on the Australian experience in containers for wastewater treatment plant, the FCCA has worked out these special tanks with the Drinktec ™ process.

The exterior is reinforced with galvanized steel beams, blasted and painted for corrosion protection. The internal is lined with a 15 mm polypropylene sheet.Options are of a single standard height container or even with two parts engageable one above another, as shown in the accompanying drawing.The length and width of the equipment is designed according to standard dimensions for easy transport.Inside, the equipment responds to the traditional Drinktec ™ process: Underdrains, internal perimeter spillways, and an in-built silo with a calcite feeding floor to assure an autonomy of more than 30 days.Underdrains are made of HDPE pipe with filtering limpets, a patented design of the FCCA.The tanks include also special feeding funnels that configurate the silo’s floor, also a patented design of the FCCA.

the worker has no free access to training in this field and therefore the jobs, and on the other, the contractor has no certificate that guarantees the company is hiring a person with the proper training.The market demands therefore, that there is a specific professional certification in these fields of assembly, operation and maintenance of desalination facilities.

PROPOSAL FOR A CERTIFIED PROFESSIONAL IN DESALINATION

The FCCA is working on a proposal that collects the needs identified within the sector, and describes the characteristics of a professional certificate in the context of "assembly, operation and maintenance of reverse osmosis desalination plants", that would reflect also the new trends in production of desalinated water.

It has selected a Spanish Medium Level as that is where a higher educational deficits and interest by the industry has been detected.

THE FCCA

The Water Canary Center Foundation (FCCA) is a private, independent and non profit organization, which has over 13 years experience in the research field of desalinated water.From within the FCCA many significant discoveries have been made that have had a significant impact on the sector. Especially those related to new treatments and equipment to improve the quality of desalinated water.Among the founding objectives of the FCCA is also promoting educational activities to help more efficient management of water resources.Thus, the FCCA has taken the role of promoting this certificate taken into consideration its experience in the desalination sector, and the importance of this technology for the economy for the archipelago. While procedure for the official certificate might take some time, the FCCA aims to develope, in a near future, a training course that complies largely with future official requirements.

Device for the injection of water supersaturated with CO2

No need to pumpThe device allows the injection of a supersaturated solution of CO2 by means of a bypass.The bypass includes a downflow tower where CO2 is injected.The tower has a special internal configuration to facilitate dissolution of CO2.The bypass flowrate is estimated accurately by means of a flow simulation program. The venturi replaces the need to use a pump.

Diverting only 5% of the flow Normally, the venturi is calculated to divert only 5% of rate through the bypass

En affordabe equipmentThe device has an affordable price since its design includes only pipes.It is meant for plants for less than 5,000 m3/day.

E l M a n a n t i a l , N r . 5 2 , S e p t e m b e r 2 0 1 2 , P a g e 2 d e 4

Lechos de calcita en contenedorDiseño: MHSFecha: 10/05/2012Estos planos están protegidos por la ley de propiedad intelectual y no pueden ser reproducidos sin autorización explícita de la FCCA

SOCIAL PROGRAM OF FCCA 2012/2014

SEARCHING FOR A SIMPLE INSTALLATION

The assembly of these underdrain pipes is carried out by first placing the main manifold in the center of the cell and closing hermetically its inlet and as well as all vertical risers of the manifold. (1)

Then, a test is performed with pressurized air to ensure the manifold is air tight. (1)

The manifold is then buried beneath a layer of concrete of 80 cm, leaving a small channel along the vertical risers. Thereafter, a protective painting is applied to the concrete. (2)

Finally, the pipes with filter limpets are layed down, anchored and then welded to the vertical risers of the manifold to configurate the underdrain grid. (3)

E l M a n a n t i a l , N r . 5 2 , S e p t e m b e r 2 0 1 2 , P a g e 3 o f 4

(1)

(2)

(3)

ADVANCES IN INSTALLING DRINTEC™ UNDERDRAIN

PIPES WITH FILTERING LIMPETS

IMPACT OF PARTIAL TREATING OF PERMEATE ON REMINERALIZATON COSTS

For large remineralization projects with limestone contactors it is sometimes desired not to treat 100% of the permeate water but only a part of it, in order to reduce the cost of the infrastructure and the footprint of the remineralization units.

Partial water treatment involves having to increase the dose of CO2 to generate more calcium and alkalinity, for the subsequent mixture with the untreated permeate to reach the desired aim.

The resulting mixture, now 100% of the flow, has to be adjusted with NaOH to increase the LSI to the desired values, generally slightly positive.

This summary presents the results obtained with a commercial simulation program (WaterPro®), adapted according to the experience of the FCCA, and with a 0%, 31%, 39% and 47% bypass respectively.

Considered permeate quality and target quality after the treatment is shown in Table 1.

As can be seen, exactly the same target LSI and pH has been assumed in all cases in order to facilitate comparison.

For these assumed conditions, chemicals consumption as given by the program are shown on Table 2.

AN INCREASE OF UP TO 15%

In Table 3 chemicals consumption is translated into euros by assuming certain market prices.

The results point to an increase cost of 15% in the case of a 47% bypass.

These costs values has been applied to a plant of 100,000 m3/d with 340 days per year of effective operation.

The results appear in Table 4.

According to these data there is an additional cost of 82,000 euros per year in case of a 47% bypass.

E l M a n a n t i a l N º . 5 2 - S e p t . 2 0 1 2 - E d i t : M a n u e l H e r n á n d e z S u á r e z • D . L . : T F 2 . 2 3 2 / 2 0 0 •

Table 1 Permeate Remineralized water

STD (mg STD/L 24,65 < 200

Ca (mg Ca/L 0,08 > 30

Alk (mg CaCO3/L) 0,11 >80

pH 5,9 7,96

LSI -7,58 0,01

ºC 16ºC 0,01

Table 2 0% 31% 39% 47%

mg CO2/L 40 64 72 84

mg CaCO3/L 85,7 126,0 138,1 153,2

mg NaOH100%//L 1,10 4,13 5,10 6,70

Table 3 0% 31% 39% 47%

CO2 (0,30 €/kg) 0,0120 0,0127 0,0132 0,0134

CaCO3 (0,05 €/kg) 0,0043 0,0042 0,0042 0,0041

NaOH100% (0,23 €/kg) 0,0003 0,0009 0,0012 0,0015

Total €/m3 0,0165 0,0178 0,0186 0,0190

% of 0% 100% 108% 112% 115%

Table 4 0% 31% 39% 47%

Total costs (€/year) 562.292,00 604.516,60 631.075,70 644.531,20

+ costs (€/year) 0,00 42.224,60 68.783,70 82.239,20