A range of chemicals are used to keep greenhouse pipework clean. They include bleach, hydrogen peroxide, chlorine dioxide and ECA water.
Growers are concerned that the use of these substances could have side-effects. With the regulations on discharging becoming ever tighter, residues could accumulate in concentrations that could be harmful to the plant, and they may even have side-effects on pathogens. This issue was investigated last year as part of the “Prevention and Control of Leaching from Greenhouses“ PPP. It started with a survey conducted among a number of gerbera growers, followed by laboratory trials in which various concentrations of products were applied to a live fungus on a Petri dish. Then two products were used in a gerbera trial to investigate whether accumulation occurred. The initial results are encouraging: for the first time, we are gaining an understanding of the behaviour of these products in comparable conditions.
In 2018 we will be seeking additional funding from grower cooperatives and product suppliers so that we can test more products. More knowledge on this subject is urgently needed, not just for gerbera but also for other greenhouse crops.
Dutch greenhouse growers manage their water flows and emissions into the environment very well compared to those in some other countries. But they could be using their water flows even more efficiently. Everything revolves around the questions “What type of water am I dealing with?” and “How can I best use it?”.
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The introduction of Priva’s Vialux M-Line has put water disinfection using UV light within the affordable reach of every horticulturist. UV disinfection will enable major improvements to be achieved in the field of disease control, efficient water consumption and compliance with increasingly stringent food hygiene regulations.
The Priva Vialux M-Line decomposes all organisms that are alive in the irrigation water used in the horticulture industry, such as fungi, bacteria and viruses. This applies equally to fresh irrigation water and recirculated drain water. UV disinfection makes it possible to safely reuse water for longer periods of time. Furthermore, this will ensure a more efficient use of costly fertilising agents, as these will no longer be discharged into the drain.
The Priva ViaLux M-Line is based on medium-pressure UV technology, which is new to the horticulture industry. The system is made up of multiple disinfection chambers, whose number depends on the size of the farm or company. In this way, every grower will be able to order a custom solution and the system can cost-efficiently grow in proportion to the business.
As the UV lamp, quartz tube and UV sensor can be replaced by the growers themselves, there is no need to call in a technician for simple repairs. Maintenance is easy, too: rinsing with acid is enough to remove any deposit from the quartz tube. The Priva ViaLux M-Line can be used as a stand-alone system or linked to process computers from various manufacturers.
Every time the system is started up, the UV sensor determines the water’s UV transmittance and adjusts the disinfection process accordingly. This enables all hazardous organisms to be decomposed, while no energy is lost due to a capacity surplus. The system is protected against lamp failure, overheating, running dry and peaks and troughs in the electricity mains. According to Priva, the Vialux M-Line will allow growers to easily comply with all existing and future statutory regulations in the field of water and food safety, and at the lowest possible cost per cubic metre of water.