Treatment of phytosanitary effluents
Phytosanitary effluent treatment systems in viticulture aim to reduce the environmental impact of the chemicals used. They include solutions such as biofiltration treatment units, phytoremediation systems and washing stations equipped with water recovery units. It is crucial to choose a system that is suited to the volume of effluent generated and the specific characteristics of the winegrowing operation, taking into account costs and the possibilities for collective management.
How do I choose my phytosanitary effluent treatment system?
Limit the volume of water to be managed on the farm
As the easiest effluents to treat are those that are not produced, we must try to reduce as much as possible the tank contents remaining at the end of the treatment and the quantities of water used to clean the machine.To limit the amount of tank bottom to be managed at the farm and the amount of internal wash water, it is necessary to :
- Calculate the volume of spray mixture to be prepared according to the surface area to be treated.
- Use equipment that is properly adjusted and accurate.
- If possible, reduce the technical tank bottom by adapting the shape of the tank to ensure complete emptying.
- Rinse the sprayer in the field: internal rinsing is essential for sprayer maintenance: it should be carried out as soon as possible after a spraying operation to avoid clogging the nozzles and filters. As we saw earlier, this involves diluting the bottom of the spray liquid tank remaining at the end of the treatment with a volume of water at least 5 times greater, and spraying it onto the plot that has just been treated.
Assessing the volumes of effluent to be managed on the farm
First of all, it's important to make a fairly accurate estimate of the quantity of plant protection effluent (tank bottom and sprayer rinsing and washing water) that you will have to collect and treat each year.Because whatever system you choose, it will be proportional to this volume. And there's no point in over- or undersizing the system.
To do this, you can fit a volumetric meter to your water inlet to measure and record the volumes of water used (for outdoor and indoor washing) in the wash area for each cleaning of your sprayers and weed-killers. Alternatively, you can calculate the time spent per wash and calculate the water flow rate to find the volume.
It is this volume of water and the quantities used over time that will guide your choice of installation.
It's difficult to give averages for the volume of water used per sprayer over a year, because it depends on a lot of parameters: what type of equipment, what washing protocol, what washing equipment, etc.
To give an order of magnitude, if we take a trailed sprayer, with 10 to 15 washes a year, we're often looking at between 1.5 and 3 m3 of effluent per year to manage in the wash area.
Take into account criteria specific to my site and my organisation
- Do I do the rinsing on the plot?
- What layout and space is available for the system?
There may sometimes be specific constraints linked to the positioning of the wash area or the lack of space, which will make it impossible to choose certain systems. - What are my washing practices (size of peak input)?
If you generate regular volumes of effluent over time, or large quantities from time to time, the system will need to be sized and installed differently for the same annual volume of effluent. - Do I prefer to have my own system or call in a specialist service provider?
- How much does it cost?
This is of course one of the main criteria to take into account. Some systems are better suited to small volumes, while others are better suited to large volumes or collective systems. - Are there any collective management projects or opportunities with neighbouring farms?
A number of collective treatment plants have been built in France, in particular by CUMAs. These facilities help to reduce the cost and running costs per farm. - If I have a winery effluent treatment plant: can this plant be used as an additional module to manage phytosanitary effluents?
- If I compost vine shoots: Is it possible to adapt my system to treat phytosanitary effluents?
- What crops are grown on the farm?
Some treatment systems are approved for specific crops. Others are approved for all crops.