Desalination: A Technology Driven Market
By China Water Risk 10 November, 2011
Amnon Levy, COO of IDE Technologies Ltd shares with us his views on the shape of the desalination market and the technology challenges that still need to be overcome.
Without doubt, desalination is a subject that stimulates debate. While proponents of desal technology view it as a solution to water crises worldwide, including the crisis persisting in China, many others view it as problematic in terms of the environmental costs such as energy consumption and the potential impacts of bulk water extraction from our oceans.
“Technologies related to seawater desalination will enjoy great policy support during the 12th Five Year Plan period especially in terms of its application in demonstration projects and Intellectual Property Right (IPR) protection. It will be a race between state-owned and foreign companies.”
Guo You Zhi, head of the China Desalination Association, GWI, May 2011.
Nevertheless, China’s government clearly intends to develop the sector despite numerous challenges and Chinese companies are expected to take up the gauntlet.
To explore the state of play in China, CWR talks to Amnon Levy, COO of IDE1, who shares his views both on the shape of the desalination market and the technology challenges that still need to be overcome.
On the maturity of the desal industry in China, Levy explains that China only really started to install desalination capacity as recently as 2003. As such, the country is still in the relatively early stages of technology development, but nevertheless is gaining experience and climbing the learning curve fast.
Finding the most efficient, environmentally friendly and cost effective model for a desalination project however is challenging, with many parameters needing to be taken into account, such as:
- Sea water quality and temperature
- Technology choice either thermal or membrane based
- Whether water produced is used for municipal or industrial purposes
- Brine discharge , either directly to the sea or for salt production
- Locally developed or imported technologies Energy (steam and electricity) cost and consumption
Levy suggests that given the technical complexity, it’s not surprising that the 11th FYP plan desal targets were missed.
IDE addresses these challenges by having in-house expertise and a suite of proven desal technologies successfully operating across a range of project conditions. This makes it easier for the company to test technologies for a given situation, when compared to other players with less experience and/ or limited access to different technologies.
Figure 1: Desalination Technology in China, 2007
RO: Reverse Osmosis ED: Electrodialysis MED: Multiple Effect Distillation MSF: Multiple Stage Flash Desalination MVC: Mechanical Vapor Compression Desalination
Levy indicates that meeting the targets for the 12th FYP appears to be more achievable than meeting the 11th FYP targets. This is because technology is accessible, demand for desalinated water is rising and the perception of desalination as a solution to China’s water crisis is increasingly accepted.
Despite challenges foreign technologies continue to lead
Meanwhile, debate is fierce at the government level as to the best technical solutions and where that technology should come from. In essence there are two main technologies to consider:
– Reverse Osmosis: the most popular technology (see Figure 1), but requires complicated intake systems and advanced pretreatment of seawater prior to the desalination process, to avoid fouling of the membranes with polluted seawater, which can affect production and functionality.
– Thermal technologies: relying on heat for evaporation and condensation to desalinate seawater, these technologies are less technically complex often being combined with power plants. For example reusing the waste heat from electricity production which can be very efficient regarding energy consumption.
For more information on desalination technologies refer to the Glossary and Measurement section of the website.
Many of these technologies and some equipment are protected by Intellectual Property Rights (IPR). Dow Chemicals for example maintain the property rights for some membrane technologies and IDE similarly has the rights for some of the thermal technologies.
Levy explains that when IDE first entered the Chinese market in 2003, the company anticipated a five to seven year window to gain market share, in advance of local players. As it turns out Levy was conservative and it seems that local players will most probably need another five to seven years to gain the necessary experience and credibility.
In the meantime, environmental and economic constraints are increasing, which in turn is constantly pushing technology innovation.
The Tianjin State Development and Investment Corporation (SDIC) Thermal Project
In the arid city province of Tianjin, heavy industrial development has driven the growth of desalination. Tianjin SDIC’s new power plant has required important quantities of water that only the sea could provide. IDE was awarded this project in 2008.
The Tianjin SDIC project, one of the world’s largest thermal plants using MED technology, and the largest desalination plant in China became fully operational in early 2010.
The project reuses waste heat in the form of steam from the power plant as well as steam from the steam turbine extractions. MED’s versatile technology allows Tianjin SDIC to use these two types of steam depending on the steam available. The brine is directed to ponds where it is evaporated, to produce salt.
Levy explains that such projects can be very efficient, notably by using waste heat to energy- and salt recovery from the brine. However the desalination plant needs to be designed at the same time as the power plant. Thus making such an approach more applicable to green projects.
Three quarters of the water produced at the SDIC plant is delivered to communities and the remaining 25% to industrial customers. The water produced reaches is of high quality, close to 5 ppm of Total Dissolved Solids1.
Figure 2. :Desalination Plant – Heat Recovery for Energy Production Illustrated
In the case of Tianjin, as well as other cities bordering the Bohai Sea, the Chinese government has prohibited the discharge of brine from the desalination process since the sea is enclosed in a bay and dilution/dispersion is potentially problematic. Consequently any desalination projects in this area will need to incorporate brine recovery for salt production. IDE is currently offering the next stage of the Tianjin project on a zero liquid discharge meaning that there is no discharge of brine to ponds.
The current cost of water for the Tianjin SDIC project, including operational costs and equipment amortization is 8 RMB/t of water. Overall, for desal projects, the water varies according to energy costs, the technology selected, seawater quality, project financing and the end use.
Figure 3: Tianjin SDIC MED Installation
Desalination – the shape of things to come
According to Levy, the role of desalination in managing China’s water supplies will be significant and possibly the only solution of sufficient scale to address China’s water crisis.
Indeed this conclusion has already been reached in other countries. Over the past 30 years for example, Spain, Israel and Cyprus has tried to address escalating water demands and the impacts of growing urbanization while dealing with persistent droughts, eventually coming to a similar conclusion that desalination is the only way ahead.
1 A global leader with 45 years of experience in the development and operation of desalination technology
2 US Environmental Protection Agency define 500 ppm to be the maximum level acceptable for drinking water.
3 Source: https://www.sidem-desalination.com/en/process/Cogeneration/GT-ST-and-DP/. Website accessed on August 1, 2011
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