The Siuntio waterworks is running an experiment, where a Finnish microbiotechnology innovation is tested in the challenging environment of a water treatment facility. ProtectPipe Bioflow -microbe solution has natural bacteria that break down the organic waste buildup in the sewage system and wastewater pumping station, thus preventing the formation of the odorous and hazardous hydrogen sulfide, and easing the maintenance of the sewer system and wastewater purification.
If successful, the experiment can have a significant impact on water treatment both in Finland and internationally.
Municipal wastewater pumping stations have a central role in wastewater purification. The pumping stations pressurize the course of the wastewater of communities and industry, for gravity alone cannot guarantee the water’s passage to the nearest water treatment facility, which is often located tens of kilometers away.
A majority of the wastewater that arrives in the pumping station is communital in its origin, and often has significant amounts of e.g. nitrogen and phosphorus, as well as solid or organic matter, such as food waste, grease, cleaning detergents, cottonwool and hair. Organic matter forms easily into raft-like components, that in large patches disturb the normal function of the pumping station.
A part of the wastewater’s organic matter may also get stuck in the challenging parts of the pipeline on the way to the pumping station. Organic matter buildup in the pipeline not only clogs the pipes, but also produces hydrogen sulfide as it decomposes. Hydrogen sulfide embrittles the structure of the pipes and causes strong odors as it rises upwards in the pipe. The strong odor of hydrogen sulfide resembles rotten eggs, and it is extremely odorous and unpleasant even in small doses. Waterworks located near settlements often struggle with both the mechanical problems caused by organic waste, and odor problems spreading to the environment.
An environmentally-friendly microbe solution
The Finnish microbiotechnology startup company ProtectPipe produces a solution containing live strains of microbes that is suitable to the needs of water treatment facilities, and removes organic waste from the pipeline in an environmentally sustainable way.
The ecological Bioflow -microbe solution travels to the areas of the pipeline with buildup, and its active microorganisms literally eat the waste, turning it into harmless water and carbon dioxide. At the same time the microbe solution prevents hazardous gases, such as hydrogen sulfide from forming, and removes unpleasant sewer odors.
The microbe solution is an eco-friendly and sustainable answer to the challenges of drainpipes. The company has alongside with microbiologists from the University of Helsinki developed a microbe population that can endure challenging environments, as well as significant changes in temperature and pH-values. The solution contains five different bacterial strains, which together clear the pipeline of grease, protein, starch, cellulose and hydrogen sulfide.
Revolutionary pilot project
Compressed waste patches and foul odors traveling to nearby settlements were the biggest challenges to the Siuntio municipal waterworks, which comprises of a total 34 wastewater pumping stations. The facility started the pilot for the microbe solution in the autumn of 2016 when other options turned out to be inadequate.
– We began with the waste patch problem in a challenging pumping station, where no technology had been effective. We noticed that as the waste patches disappeared also from even further in the system, odor problems were decreased. After this we expanded our pilot to cover other pumping stations battling with the same challenges, the director of operations of the waterworks Kaj Holmberg says.
The microbe solution is dispensed into the drain system by an automatic pump. Earlier the best solution for removing hydrogen sulfide and preventing odors has been a chemical dispenser, which however did not yield the required long-term results in challenging environments.
– For example during the dry season the currents are small, and there would be an increased need for the chemical, and this is obvious from the clear peaks in hydrogen sulfide levels. The main goal for the pilot is to find a safe and reliable system, where we know where we are at consistently. The eco-friendliness and cost-effectiveness of the new solution are also attractive for us, Holmberg notes.
Hydrogen sulfide levels are monitored rigorously at wastewater pumping stations. The limit for noticeable harmful odors is considered to be 30ppm, which has been exceeded e.g. due to seasonal changes in Siuntio during the use of the old methods. The effect of the microbes has been apparent in each pumping station after two weeks since the initiation of their use, and the limits at pumping stations in question have stayed consistently under 10ppm. The water treatment facility is feeling warily optimistic about the future of the experiment.
– I am very pleased. The final results can of course only be seen once the solution has been in standard use for longer. One year is the amount of time needed to know all circumstances for sure. It is about more than solving our problem, but if successful, this could improve water treatment and have effects more widely for the whole purification industry, waterworks and water protection. For example the amount of sludge that requires further processing could decrease in water treatment facilities, Holmberg describes.
The drainage and wastewater management of waterworks are significant targets in water protection. Developing settlements and increasing amounts of wastewater pose challenges for the industry. Additionally, waterworks must be able to deal with e.g. changes caused by global warming. The challenges in water treatment are thought to become even larger, where global cooperation is necessary. The sludge produced by organic waste is one of the biggest issues in water treatment, and its decrease could free resources for solving future challenges pre-emptively.