Here we’ve gathered the questions our clients ask most often before commissioning a desalination or water treatment plant: how the technology works, what drives the cost, how water sources differ, and what a plant needs to run for years without problems. If you don’t find your question, get in touch and we’ll answer you directly.

Frequently Asked Questions on Water Desalination & Treatment

What is reverse osmosis (RO) and how does it work?
Reverse osmosis pushes raw water at high pressure through fine membranes that let water molecules pass while retaining dissolved salts, minerals and bacteria. The result is two streams: low-salinity product water ready for use, and a concentrate stream that is discharged. Salt rejection reaches around 99% for some ions, which is what makes high-salinity water drinkable.
How much does a water desalination plant cost?
There is no fixed cost, because it depends on the required daily capacity, the salinity and salt composition of the raw water, the pretreatment stages needed, the level of control and automation, and the tank and electrical works on site. We provide a technical study and a preliminary quotation with no obligation once we have reviewed your water analysis and required capacity.
What is the difference between seawater and well-water desalination?
Seawater salinity exceeds 32,000 ppm, so it needs seawater membranes, higher operating pressures and corrosion-resistant materials, and its energy cost is higher. Well water is usually less saline but varies in hardness, silica and iron content, so it needs different pretreatment and a different chemical program. That is why design always starts from a water analysis, not from an off-the-shelf size.
What salinity range can your systems handle?
We design systems that handle raw water with salinity up to around 50,000 ppm (TDS), producing water with levels as low as about 120 ppm depending on the design and intended use.
How long does it take to build a desalination plant?
It depends on plant size and how ready the site is. The usual path is: water analysis, then the study and technical proposal, then fabrication and assembly in our Misrata workshop, then installation, trial operation and handover. Small and medium units are much faster than large plants and investment projects, and we set out a clear timeline in the technical proposal.
Do you provide maintenance and spare parts after installation?
Yes. We have a team of engineers and technicians and a maintenance center in Misrata. We offer periodic maintenance contracts and preventive visits, chemical membrane cleaning, replacement of membranes, pumps, filters and control panels, supply of spare parts and chemicals, and technical support whenever production or water quality drops.
Which chemicals are needed to run a reverse osmosis plant?
A plant typically needs an antiscalant to protect the membranes from scaling, a disinfectant for the water, an acid for pH adjustment, and a cleaner for periodic membrane cleaning. We manufacture these products at our Misrata plant: ALS 720 for most Libyan water, ALS 710 for low-salinity water, ALS 750 for seawater, ALS 2000S for high-silica water, ALS 780 for membrane cleaning, CL 700 for disinfection, and HCL 300 for pH control.
How often do reverse osmosis membranes need replacing?
Membrane life depends on raw-water quality, sound pretreatment, and a consistent chemical and cleaning program. A plant run with correct dosing and regular cleaning keeps its membranes for many more years than one operating without a chemical program. We monitor pressure, production and salt rejection to determine when replacement is due, before production is affected.
Do you carry out projects outside Misrata or outside Libya?
Yes. Our head office and factory are in Misrata, and we have branches in Tripoli, in Amman (Jordan) and in Ouargla (Algeria). We supply water treatment chemicals within Libya and to Jordan, Algeria and Syria, and we deliver projects in cities across Libya.
Can wastewater be treated and reused for irrigation?
Yes. We build sewage and industrial wastewater treatment plants that produce water fit for reuse in agricultural and landscape irrigation, in cooling towers and industrial washing, or within the industrial process itself by adding a reverse osmosis stage. The intended use determines how advanced the treatment needs to be.
What information do you need to prepare a quotation?
We need a raw-water analysis (or a sample we take on site), the required capacity in cubic meters per day, the type of use (drinking, industrial, agricultural, bottling), daily operating hours, the project location, and the water source (well, sea, mains, wastewater). With this information we prepare a technical study and a preliminary proposal.
Do you supply domestic desalination units?
Yes. We supply domestic and light-commercial desalination units for villas, offices, clinics, restaurants and pharmacies, sized and priced for everyday use, making mains or well water fit for drinking and household use.

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