There's no better time to start reclaiming wastewater

Friday, June 10, 2011

Chile is probably best known for being home to the world's driest desert, the Atacama. For visitors to capital Santiago, it can be something of a surprise to see public parks and gardens being constantly watered by automatic sprinkler systems, almost all of which use potable water.

As awareness of environmental issues grows, and the topic of water consumption becomes an increasing concern, both authorities and citizens are becoming more open to the idea of reusing treated wastewater for purposes such as irrigation.

A small group of companies has sprung up to meet this new need, including local firm WindWater, which builds compact packaged wastewater treatment plants. BNamericas spoke to general manager Guillermo Platt about the growing demand for water recycling in Chile and the technology the company is offering.

BNamericas: The reuse of treated wastewater for purposes like irrigation is something relatively new in Chile. Do you think it will eventually become widespread?

Platt: Yes, I do. It's something new, and there are a lot of people that don't know about the options available.

Chile has a lot of natural water sources, and for that reason it's a country that doesn't use its water rationally. In the north, for example, there are areas that are more critical, and water reuse is being evaluated and accepted as a possibility to become more efficient in our use of the resource, as well as transferring costs.

In the south the technology is more difficult to sell, because it rains a lot, there are a lot of rivers and lakes, and snow, even. There's a lot of water readily available.

BNamericas: In those areas where water is scarcer, do you think reusing water will eventually be seen as a solution?

Platt: Well, I'd say it's a mechanism for water management. And there are a lot of other mechanisms. But having a water plant that allows us to recycle water for non-potable purposes is a good way to make efficient use of the resource. And if the cost of water is important to me, then by avoiding throwing it away, I'm being more efficient economically.

As the process becomes more well-known, as technology and resources become more readily available and public and private institutions begin to get the idea that they need to optimize their use of water, we'll see more people reusing it.

BNamericas: WindWater offers a variety of services - can you sum up your core business?

Platt: We are mainly dedicated to designing and building wastewater treatment and recycling plants. That is, the treated water can be used for non-potable purposes, such as irrigating green areas, watering pathways, washing equipment, and etcetera.

BNamericas: Do you work mainly with industrial or domestic wastewater?

Platt: Both kinds. We have both industrial and domestic wastewater treatment plants. And in both cases, we have experience with treating the water to a quality that allows its safe re-use for various purposes.

BNamericas: What size are your plants normally?

Platt: What we normally provide are so-called compact pants. If we're talking about capacity, our plants go from 12m3/d capacity to 600m3/d.

BNamericas: What kind of technology do you use?

Platt: We use activated sludge, which is a technology that's fairly well-known worldwide. It was created in England at the start of the last century, and it has a lot of different variants. The variant we use is applicable just for small plants like the ones we build, which is the extended aeration activated sludge process.

We have evaluated this, and if there's a construction project that calls for another kind of plant, then we're of course open to using another technology. But when clients ask us to recommend which technology to use, we always recommend this kind. It's not always the cheapest, but it's the safest and generally the most stable. In fact, practically 80% of treatment plants in the world, not just in Chile, use this technology. About four years ago the EU issued guidelines, after evaluating all the technology, stating that for these small, compact plants, they recommend this kind of activated sludge technology.

BNamericas: You mentioned cost - are these plants very affordable?

Platt: Not exactly - there are cheaper solutions. Activated sludge plants are definitely not the cheapest.

The advantage they have is the high quality of the treated water, which means it can be safely reused. It's not potable, but it's very good. And it's completely clear, so if you take a glass of this water and put it next to a glass of drinking water, you can't tell the difference. It has no odor and no sediment. It does contain some contaminants in low concentrations, and it can contain biological contaminants, which is why it's not potable.

BNamericas: There are a few companies in Chile that are now offering this kind of service. Do you see a lot of demand at the moment?

Platt: Yes, there is a potentially active demand. What we need is to channel the services the market is offering. There's a lack of awareness at the moment.

There are actually still very few companies who are in this business, and a lot of them are only in it to make sure they meet the minimum environmental norms. And they only want to make the minimum investment in technology.

BNamericas: What would you say sets WindWater apart from these other companies?

Platt: We have vertical integration in our production lines. For example, we import the main equipment that we use to build the treatment plants. We also have our own plants where we build a lot of their components. This integration means we can ensure the quality of the final product.

I also think it's important that we have our own facilities, where we can assemble an entire compact plant. The client can come in and supervise the assembly even before the plant is ready. We can start up operations so the client can see it working before it's installed. I think this kind of detail is something that not all our competitors can provide.