Never too much or too little, that's what disinfecting water with UV is all aboutProfessional | Slim Fit | Tethys | 15-02-2021
In the horticultural value chain, various aspects of a cultivation add value. Sun, artificial lighting, and sometimes also packaging before a product is shipped, are all part of this value chain. However, water is also part of it and it must be clean.
Nonetheless, a UV disinfection system is not the installation that gets the most attention in a greenhouse. And it doesn't have to, at least not for the Aqualux. This UV disinfection system is equipped with automatic mechanisms that ensure that the grower does not have to worry about water disinfection apart from regular maintenance. Ruud Jansen, technician and co-owner of Artechno, explains.
"What's important is that the water is clean and is cleaned in a way that's energy-efficient. Of course, you don't want to dose too little because the water will not be disinfected properly. But it is often forgotten that dosing too much is undesirable. Ultimately that can also be harmful to a cultivation, because good substances such as iron and nutrients in the water oxidize and precipitate because the dose of UV is too high. This forces growers to re-add the nutrients while it isn't necessary. It is also harmful to the unit. Precipitation means contamination, and you don't want that in your cultivation, but also not in your installation.”
The Slim Fit model is equipped with a sand bed filter, the Pro model with a self-cleaning screen filter. The difference: with the Slim Fit the disinfection process sometimes stops briefly to automatically clean the sand bed filter, with the Pro there is no interruption. "This means the Slim Fit is an entry-level model for growers with lower capacity requirements," says Ruud.
Smart mechanisms have been built into the Aqualux to automate the UV disinfection process. However, the device has become smarter. “If you look now, you see that the pump has a frequency converter, the capacity of the UV lamps can be adjusted, and the pressure is controlled automatically. Optionally, the dosage of hydrogen peroxide can be controlled automatically. This way the disinfection process is automated in all four models of the Aqualux with different capacities.”
From left to right: Aqualux Tethys, Aqualux Professional, and Aqualux Slim Fit.
This efficiency and automatization will probably also save money. But how much? "In terms of energy, it is possible to save up to 50% of the Aqualux's energy needs, because we can reduce power by half.”
With the bigger version of the Aqualux, the Aqualux High Transmission that can disinfect more than 100 cubic meters of water per hour using 30 UV chambers, it's about 240 kWh per day. "Times 10 euro cents per kWh, that can amount to around 7,500 euro per year", Ruud calculates. "Every grower has to disinfect nowadays, so you want to do it as efficiently as possible. We can say that the annual savings are a bonus on Aqualux's ROI. The most important factors of this machine are the reliable disinfection, a good purchase price, and easy maintenance, resulting in a quick payback period and low maintenance costs.”
Back in the greenhouse. What does the grower have to do when the Aqualux runs? “Nothing, really," says Ruud. "Except for regular maintenance, the user doesn't have to worry about anything else. With a new cultivation, for example, the water is often dirtier in the beginning. It has a lower transmission rate than in the middle of cultivation or in the summer when the volumes also increase. The Aqualux adapts constantly during cultivation to obtain the desired disinfection by controlling the flow, flow rate of the pump, and the power of the lamps. And for growers who dose hydrogen peroxide, there's also automatic dosing for that.”