Chemistry & Life Sciences

Membrane Technology in Chlor-Alkali Plants

How WeylChem PPC is Phasing out Mercury

17.12.2013 -

Phase Out - Mercury contamination continues to be an environmental and public health concern. The World Health Organization considers mercury as one of the top 10 chemicals posing a threat to public health. This is certainly one of the main reasons why in Europe, chlor-alkali producers using mercury technology are committed to phase-out by the year 2020.

European producers have about 7,600 tons of liquid mercury used by 34 electrolysis plants in 15 countries. These units account today for 31 % of European chlorine capacity. The objective set for the end of 2010 was to have less than 35% of mercury based production in total. As a result, the gradual shift away from the mercury cell technology continued, accounting for 30.6% of the total installed capacity in 2011. The Industry achieved the target set, even more than was previously anticipated. The more energy-efficient membrane technology accounted for 51% of 2011 European chlorine capacity

Why Ban Mercury?

Mercury in the air may settle into water bodies and affect water quality. This airborne mercury can fall to the ground in raindrops, in dust, or simply due to gravity. After the mercury falls, it can end up in streams, lakes, or estuaries, where it can be transformed to methylmercury through microbial activity. Methylmercury accumulates in fish at levels that may harm the fish and the other animals that eat them. For the environment, this means a threat to the entire food chain, thus to the health of humans and wildlife. A significant example of how harmful and hazardous the discharge of mercury occurred in the Japanese village of Minamata. A nearby factory discharged waste contaminated with mercury over several decades. It is estimated that more than 50,000 people were affected in one way or another, resulting in severe cases of brain damage and paralysis, among other possible side effects.

Membrane vs. Mercury

The advantages of membrane technology vs. mercury are that energy consumption is 30% lower, and mercury emission is zero, thus no environmental pollution. Besides lower operating costs and ease of handling and operation, one other significant advantage is that the product purity is higher. What does this mean for the industry? Offering a range of mercury-free raw materials to the market will bring more environmentally friendly products to the end users.

Secured Future

WeylChem PPC, one of the major producers of chlorine, bromine derivatives and potassium derivatives, is one of the first to announce the full production switch to membrane technology. Potasse et Produits Chimiques (PPC), located in Thann, France, has started with the conversion of its production unit of chlorine and potassium derivatives via a mercury-based electrolysis to membrane technology. In parallel, PPC is to carry out an upgrade and extension of the current bromine recovery capabilities on site which should lead to significant cost savings for bromine. The total investment for both projects will be€ 53 million. Bank financing has been secured from Commerzbank, while the equity portion of the financing will be provided by International Chemical Investor's Group (ICIG). Chemieanlagenbau Chemnitz (CAC) has been selected to build the new membrane electrolysis plant and the bromine recovery plant, having extensive experience in the segment of erection, re-vamping and expanding electrolysis plants. The works should be completed by September 2015.

"This investment is proof of ICIG's long term commitment to a sustainable presence in the market of potassium and chlorine chemicals and underlines the importance of WeylChem PPC as a key player in this field," says Tomas Hainich, president of the WeylChem Group.

The site in Thann, founded in 1808, is the oldest chemical site in France. For the stakeholders in the region, it means a safer future in terms of environmental protection. It also means that PPC is one of the chlor-alkali production sites that will remain in Europe after the year 2020, securing jobs on site but also the supply of chlorine to neighboring companies. Although supply exceeds demand, the industry is dependent on the major players, such as PPC.

"This project is a major milestone in PPC's life. We are giving PPC all the means to secure its future and to operate with the best available technology," says Philippe Robin, PPC's CEO. "In addition, our project has received a strong support from local authorities will sustain the whole product portfolio."