FEATURE

8Membrane Technology February 2007

With 19 million inhabitants, the metropolitan region of São Paulo in Brazil is one of the five most populous cities in the world.

Since 1980, its population has more than doubled, also turning it into the largest indus-trial centre in Brazil. Although this rapid growth has increased economic development, it has also considerably increased the pollution of the air and water, especially in the city’s two principal rivers, the Tietê and the Pinheiros.

Water conservationTo conserve water and reduce the emission of effluents, and other environmental pollutants, many local factories are installing environment-friendly systems.

Cia Nitro Química Brasileira is one such example – having reduced natural gas consump-tion by 45% and consequently, reducing the emission of gases and the discharge of effluents from the boilers by 90%.

As a leading chemicals company, the plant produces each year 328 000 tons of nitrocellu-lose, fluorhydric acid, aluminium fluoride and sulphuric acid, which are used in a wide variety of sectors for the manufacture of varnishes and lacquers, aluminium materials, herbicides and fertilizers, and in the chemical, steel, petroleum, alcohol fuel, paper and cellulose industries.

Demineralized waterThe plant’s production process demands a sig-nificant volume of high purity demineralized water to generate steam.

In order to reduce water consumption and reduce the emission of effluents, the plant’s man-agement decided to install a system for produc-ing demineralized water that uses reverse osmo-sis (RO) technology developed by GE Water & Process Technologies, a business unit of General Electric Company (GE).

The factory workers noticed that the water softening process which was being used did not

produce water of sufficient quality to refill the boilers. The formation of scale and ‘incrustations’ reduced the thermal exchange considerably, and consequently the efficiency of the boilers. This significantly increased energy consumption.

MaintenanceThe cost of maintenance was also significant, and compromised the availability and reliability of the plant’s systems.

In order to minimize these problems, it was necessary to regularly empty and ‘bleed off ’ of discharge water from the boilers, which caused an increase in the consumption of water and effluents, and a greater consumption of fuel and chemical products. The problem was aggravated by the installation of a compact boiler, with a greater vaporization charge.

Reverse osmosisThese operational difficulties, together with the company’s desire to reduce natural gas and water consumption, prompted the plant to improve its steam-generating system by installing

RO technology helps chemical plant reduce water consumptionThis case study shows how reverse osmosis technology, developed by GE Water & Process Technologies, is helping a chemicals plant in Brazil reduce both natural gas consumption and effluent discharge.

‘Ecomagination Leadership Award’ for Brazilian chemicals companyGE Water & Process Technologies, a unit of General Electric Co (GE), honoured Cia Nitro Química Brasileira, Group Votorantim, with a 2006 global ‘ecomagination Leadership Award’.

The company, a leader in the chemical indus-try, was recognized for the successful implemen-tation of GE’s water purification and eco-friendly technology – reducing natural gas consumption by 22% and effluent discharge by 90%. It was among four companies worldwide that received this award.

GE initiativeThe ‘ecomagination Leadership Award’ is a GE initiative throughout the world to recognize customer’s projects that work to protect the envi-ronment and promote energy efficiency, lower harmful emissions, increase supplies of water and reduce operational costs.

The Brazilian project undertook, for about two years, a study involving situation analysis and project development tools, with the objective of increasing the company’s production potential,

while decreasing the use of water and energy. The company obtained excellent results – it

reduced effluent discharge, saved millions of litres of water, reduced consumption of natural gas and improved production.

Improving the environmentThis award was launched during 2005 and GE says that is represents its commitment to improv-ing the environment.

The company aims to bring to market the technologies that will address its customers toughest problems and environmental needs, while promoting continuous improvement of businesses performance.

Under the ‘ecomagination’ initiative [Membrane Technology, June 2005, page 1] GE is planning to invest US$1.5 billion in the research and devel-opment of leaner technologies by 2010; to dou-ble the revenue of ‘ecomagination’ products and services that provide advantages to customers and the environment (from $10 billion in 2004 to $20 billion in 2010); reduce the intensity of gas emissions (greenhouse gas) and improve energy efficiency; and ensure that the public is informed through reports that highlight the progress made towards achieving these goals.

Contact: General Electric Company, 3135 Easton Turnpike, Fairfield, CT 06431, USA. Tel: +1 203 373 2211, www.ge.com/ecomagination

FEATURE

9Membrane Technology February 2007

RO technology from GE Water & Process Technologies, and adopt new measures that aimed to make the operation more economical.

‘We chose the RO system from GE because of the company’s excellent reputation, com-petitive financial proposal, and a guarantee that it would meet our strict performance standards,’ affirmed Rosan Coutinho, Energy Department Manager, who is responsible for

the distribution of utilities and plant produc-tion of sulphuric acid.

ReductionsBy producing high purity water using the RO system the effluents from the boiler discharge were reduced by 90%, which also reduced energy loss or wastage.

A reduction in effluents of 106 200 m3/year (2.5% of the total plant) was also achieved, as was the consumption of water in an equivalent amount. In turn, these changes reduced the relative costs of industrial wastewater by US$75 000 per year and the consumption of water by $29 500 per year.

The company says that the boilers now operate almost continually, without the frequent interrup-tions that were required by the previous water treat-ment system. In addition, the boilers now operate in compliance with the ASME/ABMA directives.

The incrustations that formed within the boilers were minimized substantially, and now the boilers operate in a more efficient manner. The plant has managed to reduce natural gas consumption by 7 461 000 m3/year, and has reduced, in propor-tion, greenhouse gas emissions.

As a result, the firm has directly saved over $2m a year. In addition, by ensuring that the plant oper-ates more efficiently, Cia Nitro Química has also reduced its annual electrical energy consumption by 6672 MWh, saving $320 000 per annum.

Environmental benefits‘The project has met our expectations for financial gains, operational efficiency, and environmental benefits,’ said Coutinho. ‘In financial terms, the RO system was easily justified, showing an excel-lent return on our investment. And, as a business with 70 years of history and a deep commitment to this region, the environmental benefits are also extremely important to us.’

Contact: GE Water & Process Technologies, 4636 Somerton Road, Trevose, PA 19053-6783, USA. Tel: +1 215 355 3300, www.gewater.com

GE upgrades water treatment plant with EDR technologyGE Water & Process Technologies, a business unit of General Electric Co (GE), is upgrading Aigües Ter-Llobregat’s (ATLL) existing water treatment facility in Abrera, Spain with its electrodialysis reversal (EDR) technology.

Safe drinking waterGE’s water treatment technology will assist ATLL in supplying a trustworthy drinking water source for approximately 20% (200 000 m3 per day) of Barcelona’s metropolitan region. When completed, the facility will be the world’s largest EDR plant – at nearly four times the size of its predecessors – claims the company.

‘GE technology will help provide a consis-tent source of safe drinking water for the peo-ple of Barcelona,’ said Jeff Garwood, President and Chief Executive Officer of GE Water & Process Technologies.

‘By providing an efficient, dependable and contaminant-free water supply, GE works to

empower industries and communities like Barcelona with the right technologies and sys-tems to resolve their water quality, scarcity and regulatory concerns.’

Pilot projectFor the past two years, GE and ATLL pilot-ed the project with a focus on increasing Barcelona’s supply of quality drinking water.

GE’s EDR technology uses an electro-chemical separation process to remove potentially harmful contaminants found in many source waters, like Barcelona’s Llobregap River. While improving the over-all availability of quality drinking water, the technology will also allow the facility to operate at the exceptionally high water recovery rate (90%); strategically deal with a dynamic water source; and resist fouling that can decrease a plant’s operating perfor-mance or even shorten the overall service life of a facility. The technology will also help the plant improve overall efficiency and productivity.

Under the agreement terms, GE will oper-ate and maintain the ATLL project, with upgrades estimated at $25 million, for a two-year term.

Desalination membranes produce potable water in Algeria and Spain

Algeria has never had enough water for its people. Since the Berbers first arrived there in 10 000 BC, access to clean water on a daily basis has been a constant struggle for this North African coastal country.

Centuries of drought in the region, in com-bination with long-term mismanagement, have depleted the country’s ground water sup-plies, as well as the dam reserves, to sub-critical levels.

Intermittent suppliesToday, many cities, including the country’s capi-tal Algiers, have water systems that work for only a handful of days out of each week.

The World Health Organization considers a country to be ‘water stressed’ if the annual avail-ability of clean water per person is below 1700 m3. Without immediate action the figure for Algeria is predicted to drop to a level of less than 1000 m3 by 2025.

US-based membrane technology company Hydranautics is supplying desalination membrane elements for use in major projects in Spain and Algeria in North Africa. They will be used to help alleviate water shortage problems in these countries.