Chinese Membranes Have Promising Market in Water Treatment

By Yang Kun, Ma Jun, Zhang Xuefa, National Environmental Protection Membrane Engineering Technology Center  

The global membrane market has had a strong growth trend from the beginning of this century, with total sales revenue reaching US$11 billion in 2011. China's membrane sales revenue was about RMB7.13 billion, among which RMB2.68 billion was contributed by reverse osmosis (RO) membrane/ nanofiltration membrane; RMB4.45 billion was by microfiltration and ultrafiltration membranes. Universal membranes sales alone in the Chinese market accounted for 20%-30% of the sales revenues in global market. It is obvious that China has become the world's largest membrane sales market.
   Industrial wastewater and municipal wastewater could be reused for industrial water (recycled water, process water, cooling water), pure water or ultrapure water through deep treatment by a membrane (such as NF, MF/UF+ RO, MBR). (Municipal wastewater also requires a secondary biological treatment.) At present, membrane treatment accounts for over 95% of the global wastewater water (sewage) recycling.
   Over 90% of the river water, lake water and groundwater in China have some degree of pollution. In addition, the geology micro polluted water like high concentration of fluoride and nitrate in groundwater in some regions also needs attention. In response to the growing problem of surface water pollution and water security emergencies, Europe, America and Japan are drawing up stringent measures and technical countermeasures, and membrane technology is generally agreed to be one of the leading technologies. It is reported that the current global could process 22 million cubic meters of water every day using only microporous membranes. Japan is actively promoting the application of membrane technology in drinking water. The Japan Water Works Association also stipulates the specifications of a membrane module. Europe has adopted membrane technology for most of the newly built water plant since 1990. The very large membrane filtration water purification plant planned by the United States will process 1 million cubic meters every day. Since 2009, China has also started to build membrane water treatment plants in Hangzhou, Wuxi, Dongying, Nantong, and Beijing, with single processing capacity reaching 100 000 to 300 000 m3/d, and this trend will be reinforced by the execution of the new national drinking water standard in 2012.
   In the municipal field, it is expected that the investment in wastewater treatment in the period of 2011-2015 and the period of 2016-2020 will reach RMB1.29 trillion and RMB1.56 trillion respectively. The investment in processing industrial and urban sewage will reach RMB575.3 billion and RMB557.8 billion respectively.

Industrial boilers/process water

Membrane separation technology applied to industrial production could save raw materials water resources and realize energy conservation, and could even upgrade traditional processes for manufacturing some products to achieve cleaner production. China has introduced stainless steel micro-filter membrane to filter fermentation broth in lysine production, which can reduce 50% washing water and significantly shorten the washing span; it also introduced membrane technology in the monosodium glutamate (MSG) production, with 30% - 40% reduction in water consumption and no waste residue through the whole process; China also recovered 63% hydrogeny gas in synthetic ammonia gas exhaust via gas separation membrane.
   In 2010, the Chinese ultrafiltration membrane market had a total sales revenue of RMB4.45 billion, with sales volume reaching 820 000 membrane modules. But the capacity was 40 million m2/a, far exceeding the total market demand. Over the same period, the RO market sales revenue reached RMB2.59 billion, with total sales volume of 475 000 (converted to 10.5-inch membrane modules). Overall, the supply and demand has been showing signs of market saturation for UF and RO membranes. Membrane manufacturers have only two choices in market orientation. One is to improve product performance. The other is to lower the prices. Producing high end membrane products for foreign markets such as India and North America will be an inevitable choice.

Industrial wastewater treatment

China's petroleum and chemical industry consumes 1.8 billion tons of water every year, and annually discharges about 900 million tons of sewage with toxic and harmful contaminants. Oil extraction annually needs over 1 billion tons of reinjection water, which has relatively high requirements in water quality. While it is difficult to separate injection water by conventional methods, ultrafiltration and microfiltration are usually considered to be the most effective ways to deal with oilfield sewage. China has an annual processing needs of about 600 million cubic meters in oil extraction field. China has more than 10 000 pharmaceutical enterprises and over 2 000 dye enterprises, and their production processes generate a considerable amount of wastewater. At present, 80% to 90% of industrial water in China is used as cooling circulating water, and the treatment and reclamation of such water is crucial to industrial water conservation. Developing wastewater resources is imperative in the future.
   In the late seventies, Japan and the U.S. had successfully treated civic wastewater (sewage) to be drinking water through integrated membrane treatment. In 2002, Singapore built the Bedok Newater Plant with processing capacity of 32 000 m3/d and the Seletar Newater Plant of 24 000 m3/d in Jurong Island industrial park. The two plants purify secondary treated municipal wastewater via integrated membranes into direct drinking water (called new water) which meets the international drinking water standards and can be blended with a ratio of 2% into the municipal drinking water network. While the recycled water could be alternatively be used as ultrapure water for the semiconductor industry. In recent years, the refining industry and power generation industries in China successfully treats municipal sewage water to produce boiler water, process water and water for household uses through dual-membrane technique, and also treats industrial wastewater via membrane bioreactor process and realizes water reuse.

Desalination of seawater and saline water


At present, strong brine attracts the most attention in comprehensive utilization, impact on the environment and its countermeasures. The main seawater desalination methods include multiple stage flash (MSF), low-temperature multi-effect evaporation and RO, among which the RO method consumes the least energy with energy consumption of 3 kWh/m3 (pilot scale can be reduced to 1.58 kWh/m3), and the price of membrane components is only tenth that of 10 years ago, so that the water treatment costs fell 67%. Seawater desalination plants using the RO technique feature quick construction – a plant with processing capacity of 10 000 m3/d could be completed in 7 months. In addition, the current RO desalination attaches great importance to water and power cogeneration, as well as the integration and optimization of chemical production process.
   China is undertaking the enormous South-to-North Water Diversion Project. It is reported that the price of water to arrive in Beijing, before any treatment in the municipal water supply network, may reach RMB6.9 per cubic meter. The current RO desalination price per ton of water is below this level, and thus water industry and coastal cities are considering the implementation of large-scale seawater desalination projects to provide municipal water and industrial water.
   In the "12th Five-Year Plan" period (2011-2015), China will actively promote the RO method seawater and saline water desalination technology, and will build new RO desalination capacity of 1-1.5 million m3/d. China also plans to launch 200 000 - 250 000 m3/d of RO membrane system and 100 000 m3/d of ion-exchange membrane electrodialysis system for saline water desalination.

Tap water standards improve

Membrane technology is a developing trend for drinking water and micro-polluted water treatment. At present, Japan waterworks has a daily water production of 50 million to 60 million cubic meters, among which one million cubic meters is processed via membrane technique. China is just at the beginning of developing membrane technology in drinking water treatment. In 2012, China will enforce all the 106 clauses of the new Drinking Water Standards, the requirements of which are impossible to meet by traditional means. Thus China must vigorously develop the high quality drinking water production with ultrafiltration or microfiltration membrane technology as the core processing technology, for it is not only needed in cities, but also in small towns.