Blatant Reality

A new process for purifying water by using algae has energy potential as well.

The algae are a component of the system that treats and filters the wastewater by removing certain contaminates, such as phosphorous, and breaking down solids. According to Limcaco, “the system is basically an algae farm using the wastewater as fertilizer”. The resulting sludge is a mixture of wastewater solids and algae. This mixture is then thermally treated using a process similar to gasification, a technology that has been around for years. During the thermal process, oils are removed from the sludge mixture in stage one, and the remaining solids are gasified to produce electricity and high grade fertilizer in stage two.

 

The system has numerous environmental and cost benefits. First, the carbon dioxide emissions generated by the thermal process are looped back into the Algaewheel system where the algae thrive on the gas, which gives the system a negative carbon footprint, and potential carbon credits. Second, the use of algae in the filtration and treatment process also reduces the need for some chemical-based treatments. Third, the energy produced by the system is used in the operation of the facility in the form of heat and electricity, and depending on the size of the facility, it is possible to generate excess energy that could be sold to the electric grid. Fourth, oils extracted from the wastewater sludge and algae mixture can be used to produce bio-fuel. Lastly, the solid byproducts are 95% less than a traditional system because the only byproduct of the process will be a small amount of solids which can be used as high grade fertilizer. The fertilzier is safe to transport and easy to dispose as compared to the traditional handling of wastewater sludge byproduct, which often involves transporting and dumping hundreds of tons of sludge on farm fields or in a landfill.

Now this, from an environmental standpoint, will have all the greens jumping up and down for joy at the thought of such an eco-friendly water purification. However, at this point I am just waiting for the little side note that this system is extremely expensive and not economically feasible. The good news is that as I continued reading, I never did find that. In fact, this is what the article said about costs (my emphasis):

The combination of reduced chemical usage, self-contained energy production, and minimal byproducts delivers a remarkably environmentally friendly and cost efficient system. In fact, the operating and maintenance expenses of this type of facility are less and tend to be much more stable over the facility’s useful life because part of the energy costs and the treatment costs are not subject to the price fluctuations of energy and chemicals. According to Limcaco, the operating and maintenance cost of an Algaewheel plant can be up to 30 percent less than a similarly-sized traditional facility. To top it all off, the useful life of the facility is estimated at 30 years, which is about 30% greater than traditional facilities.

If this actually is the case, then by all means we should invest in these facilities. I’m all for “green” alternatives if they are both economically feasible and efficient. With the added potential of a non-crop biofuel, this process is definitely something to keep a close eye on.