Cooling Water Systems & Ozone Water Treatment: 190-Day Test
The cooling water systemis central to both air conditioning and production processes in industrial plants. Where water quality is not properly managed, scale, biofilm and equipment corrosion can develop, driving up energy consumption, shortening equipment life, and raising maintenance costs.
Many organisations are now adopting Ozone Water Treatment as an alternative approach to managing cooling water: reducing chemical use, controlling microbiological growth, and maintaining the efficiency of cooling tower and condenser water systems.
Case Study: Cooling Towers at Five Large Retail Branches — Condenser Approach Held Below 4°F for 24 Months
In the air conditioning systems of large buildings, chiller efficiency does not depend on the chiller alone. It also depends on the cleanliness of the heat rejection system, particularly the condenser and the cooling water system connected to the cooling tower. If scale, algae or biofilm begin to accumulate on the heat exchange surface. Even in small amounts, the chiller can consume more energy than necessary.
One of the key indicators building engineers use to track abnormalities in the system is the Condenser Approach Temperature, or approach value, which directly reflects the condenser’s ability to transfer heat. A low value indicates the system is still exchanging heat well. A value that rises steadily is usually a sign that the tube surfaces are becoming fouled, that scale is accumulating, or that fouling is developing inside the system.
This article presents a case study from five large retail branches that changed from conventional chemical water treatment to an ozone water treatment system in the cooling tower’s cooling water circuit, and were able to hold Condenser Approach below 4°F continuously for 24 months.
Case Study: Over 10 Million Baht a Year Saved with a Chemical-Free Ozone Cooling Water System
Managing energy costs in large buildings, particularly hospitals, which must run air conditioning 24 hours a day. Represents one of the principal unavoidable costs. One frequently encountered problem is the accumulation of scale, algae and bacteria inside the condenser and the cooling tower, which reduces heat transfer efficiency, causes the chiller to work harder and consume more energy than it should, and drives electricity costs higher.
This case study took place at Faculty of Medicine – Khon Kaen University, which chose to install ECONOWATT’s chemical-free ozone cooling water treatment system, model OZG 120 S, with real operating results recorded over a total of 730 days. The outcomes were clear across energy, financial and environmental dimensions.
5 Factory Wastewater Problems That Modern Treatment Systems Can Solve
Industrial wastewater problems affect corporate image, regulatory compliance, and the environment. Wastewater treatment systems therefore play a vital role in helping factories raise operational standards, reduce resource consumption, and move toward greater sustainability.
This article summarizes five common industrial wastewater problems, along with practical solutions using modern treatment technologies—from preliminary treatment to advanced processes that factory owners can apply to improve wastewater management effectively.
What is a wastewater treatment system?
5 wastewater problems that an industrial wastewater treatment system can solve
Solving these problems with an industrial wastewater treatment system
Install a modern wastewater treatment system for sustainable industrial standards
Frequently asked questions about wastewater treatment systems
A wastewater treatment system is the process of removing contaminants from wastewater generated by use in an industrial plant. Applying wastewater treatment technology produces clean, good-quality water before preparing it for a water recycling system. Wastewater can be treated by a number of methods, physical, biological and chemical, depending on the wastewater problem in question.
Beyond turning wastewater into clean water, installing a wastewater treatment system in an industrial plant has a number of other advantages:
Industrial wastewater problems can range from minor issues to serious challenges with large-scale impacts. The following are 5 common wastewater problems that can be effectively managed with wastewater treatment systems.
The problem of foul-smelling wastewater usually arises when there is too much organic matter in the water, requiring the microorganisms used in treatment to consume large amounts of oxygen for decomposition, producing hydrogen sulphide (H₂S) and ammonia. This results in BOD (Biochemical Oxygen Demand) and COD (Chemical Oxygen Demand) values above standard. Normally, BOD must not exceed 20 mg/L and COD must not exceed 120 mg/L.
Under the Ministry of Industry Notification on the control of effluent standards from factories, B.E. 2560 (2017), if discharged water has BOD and COD values above the standard, legal penalties apply for example, financial penalties, an order to cease discharging wastewater, or the licence being considered for revocation.
Food and beverage processing plants, and plants manufacturing metal components, frequently encounter the problem of discharged water contaminated with oil, grease and residual chemicals. Without good wastewater treatment technology, this leads to floating sludge, blockages in drainage pipes, and wide-ranging environmental damage, because grease adhering to the water surface obstructs the transfer of oxygen from the air into the water, reducing dissolved oxygen and affecting aquatic animals and the aquatic ecosystem.
Wastewater containing large quantities of minerals results in severely polluted water. When it escapes and contaminates natural watercourses, the environmental impact is severe. It can be removed by chemical stabilisation to precipitate the contaminants, together with filtering out remaining highly charged ions through an Electro Conductivity Reducer (ECR) system or RO, before discharge to the public environment or the mineral-filtered effluent can be recovered for reuse. The minerals separated from the wastewater must then be crystallised into a solid form.
Wastewater with large quantities of sediment and suspended solids arises from raw material washing, or from production processes contaminated with organic and inorganic matter such as gravel, clay, sand and material fragments. Without appropriate wastewater treatment technology, suspended solids remain high, causing blockages within the treatment system. If discharged into public watercourses, this creates turbidity, reduces oxygen levels in the water, endangers aquatic life, and ultimately accumulates as bottom sediment.
Many plants have a problem with large volumes of wastewater accumulating, particularly during periods when production must be accelerated. If an unsuitable wastewater treatment system is in use, wastewater overflows the treatment tanks and the system blocks easily. Wastewater must then be released from the plant into natural watercourses. Which may lead to financial penalties or a legal order to cease discharging.
Get a modern, high-efficiency wastewater treatment system designed and installed by the expert team at Econowatt. Our solutions help factories treat wastewater effectively and produce high-quality clean water for reuse within their operations.
Learn more about our available solutions on the Our Solutions page.
Installing a wastewater treatment system to address these problems generally divides into 3 treatment stages:
A physical treatment stage that separates large, water-insoluble contaminants using screens, passing them into a settling tank. Some plants may add a grease removal system to reduce problems with grease accumulation in the wastewater. Preliminary treatment methods include:
Treatment at this stage focuses on reducing the contaminant load of the wastewater by chemical or biological means. The method must be considered against the characteristics of the wastewater in each case. Wastewater treatment systems used at the secondary stage include:
Advanced wastewater treatment is a process for removing suspended solids that are difficult to settle, along with nutrients and colour that cannot be removed at the intermediate stage. In most cases, installing wastewater treatment technology at this stage is intended to bring water quality to the highest level so that it can be safely reused. Systems used at this stage include:
An industrial wastewater treatment system is an innovation that delivers real value to industrial plants today. Beyond complying with Department of Industrial Works requirements, it also helps improve production efficiency and establishes long-term sustainability standards for the plant.
For plant owners looking to install a quality wastewater treatment system suited to real-world operation, Econowatt designs wastewater treatment systems and advises on installation to solve wastewater problems, with more than 30 years of experience. We are ready to be the partner that raises your production and wastewater treatment standards to meet requirements and move towards genuine sustainability.
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Reference: กรมโรงงานอุตสาหกรรม
A: The system uses microorganisms to help decompose organic matter in wastewater, with aeration added so the microorganisms can work at full efficiency. This helps reduce BOD and COD values to within standard levels.
A: Yes. Every factory producing discharged water from its production process must comply with environmental law, in order to help reduce the impact on surrounding communities.
A: New technologies such as MBDAF and EHR use less energy than older wastewater treatment systems and can be configured to operate automatically, helping to reduce costs over the long term.
A: Yes, provided the water recycling system has been properly designed. However, the water should be filtered and its quality checked before every use.
Ozone Water Treatment for Chillers: Hospital Case Study
The cooling water system is a critical component that directly affects chiller performance. When scale, biofilm or algae accumulate inside the condenser tubes, heat exchange declines, the machine works harder, consumes more energy, and brings with it ongoing chemical and maintenance costs.
A leading hospital in Bangkok switched from chemical water treatment to the ECONOWATT Ozone Water System, model OZG209N5Y, to manage its cooling tower and condenser water. Comparative data was collected from October 2025 to May 2026. The result: the Condenser Approach Temperature of both chillers fell noticeably, with no condenser tube cleaning performed, and with the machines running at higher load than before.