Installing a filter barrier with reverse osmosis

This one is the onereverse osmosis barrier- it would seem that this is a hackneyed topic, but every time I come across projects, I come across the fact that people confuse household and industrial models. Especially in agricultural projects, where water is needed not just for drinking, but for technological purposes. I remember once the contractors installed household osmosis on a drip irrigation system - after a month the membranes began to crumble from iron. And the passport clearly states: preliminary cleaning is mandatory. But no, everyone thinks - it’s plugged in and it works.

Why is reverse osmosis not just a filter?

When you orderinstallation of a barrierfor a greenhouse complex, the first thing you encounter is the selection of productivity. Recently worked on a projectShandong Linyao Intelligent Agriculture Technology Co.,Ltd— there they just needed water to prepare working fertilizer solutions. If you take a standard household unit with a capacity of 200 l/day, then to water 1 hectare of greenhouses you will have to install a battery of 20 systems. And these are questions about communications and regeneration.

By the way, about regeneration, many people forget about washing membranes. I have seen cases where in systems without automatic flushing with hardness salts, the channels became clogged within six months. We had to change the entire module, although we could have simply added a valve with a timer.

Another point is connecting to the highway. In the same project forfilter barrierI had to make a separate stainless steel piping because polypropylene did not hold a pressure of 6 atm. Although for household systems there are usually enough plastic fittings.

Costly installation mistakes

The most common problem is saving on prefilters. They install one mechanical cartridge for 5 microns, and then they are surprised thatreverse osmosisrequires membrane replacement every 3 months. In agricultural projects, especially where the water is from open sources, at least three-stage preliminary purification is needed: a mesh filter, a carbon filter and again a mechanical one.

I remember a case at a facility in the Rostov region - a system was installed there without taking into account seasonal fluctuations in water quality. During the spring flood, sand passed through all the steps and killed two membranes in a week. We had to urgently install additional cyclones.

And yes, about the pressure in the network - if it is below 2.5 atm, you need a booster pump. But it is often forgotten to be included in the scheme. As a resultbarrierit simply does not start, or works with minimal efficiency.

Specifics for agricultural projects

BShandong Lingyao Co.,LtdWhen designing irrigation systems, we always reserve a productivity margin of 25-30%. Because in field conditions, water often contains organic matter, which clogs prefilters faster. By the way, for floriculture farms, stable quality of purification is also important - if the TDS jumps, the plants react by dropping buds.

We recently discussed with technologists the issue of concentrate disposal. On an industrial scale, pouring it into drainage is not an option. You have to either use it for technical needs or use recovery systems. But this already increases the cost of the project by 15-20%.

More from practice - smart greenhouse complexes often require integrationreverse osmosis filtersinto the general management system. Here it is important to provide data output on pressure, permeate quality and time before chemical washing.

About equipment and materials

The situation with membranes is now interesting - many are chasing American ones, but for agricultural purposes Chinese analogues are often sufficient. The main thing is to follow the washing schedule. By the way, inbarrier osmosisFor farms, it is better to install membranes with a reserve area - this way they work longer with variable quality of source water.

The prefilter housings are made of fiberglass only. Plastic in the sun in the field cracks within a season. Have you seen such “petals”? on one of the farms in the Krasnodar region.

And about the connecting lines - if you use HDPE, take technical, not food grade. It better withstands water hammer, which is inevitable when working with pumping stations.

When is reverse osmosis really needed?

In projectsShandong Linyao Intelligent Agriculture Technology Co.,Ltdwe always do an extensive water analysis before recommendingreverse osmosis installation. If salinity is below 800 mg/l, ion exchange is often sufficient. But for nutrient solutions - only osmosis, otherwise the salts will block the absorption of microelements.

I remember in Crimea we had to redo the system - the customer insisted on softeners, but demineralized water was needed for the tomatoes. In the end they installed it anywaybarrier, but with loss of time and money.

Nowadays, for most greenhouse complexes, we consider cascade systems to be optimal - first osmotic cleaning, then dosing fertilizers into the permeate. This makes it possible to achieve a stable composition of the nutrient solution.

What else is important to consider

The point that is often overlooked is the water temperature - for normal operationreverse osmosisyou need at least +15°C. In unheated rooms in winter, productivity drops significantly. You have to either heat the water or insulate the lines.

More about chemical washings - many try to use household products, but industrial membranes require special solutions. Otherwise, the selective layer may be damaged.

And lastly, never skimp on the automation unit. Manual control industrialinstalling a barrieralways leads to the human factor. Either they forget to open the valve, or they don’t change the timer to winter time.