TL;DR

1. Global Water Challenges: Their is an escalating need for clean water due to rising global population, climate change, and challenges in water extraction. It emphasizes the importance of innovative water treatment technologies to meet these demands.

2. Current and Emerging Technologies in wastewater treatment: We look into current water treatment techniques, highlighting their inefficiencies and environmental impact. We explore advanced solutions, focusing on sustainable, energy-efficient methods and the potential for material recovery and energy generation.

3. Interesting Investment Trends in water treatment: Challenges such as slow adoption, regulatory hurdles, and the conservative nature of the water industry make it a challenging space for VC investments. We remain very optimistic, water technologies are crucial for global sustainability and exciting companies are making incredible progress in the space.

Introduction

Water is an essential resource for life, but it is becoming increasingly scarce and valuable. Some have referred to it as liquid gold.

With the growing challenges of climate change, population growth, pollution, and urbanization, there is a rising demand for clean and safe water. The question arises: how can we meet this demand while safeguarding the environment? One solution lies in investing in innovative water treatment technologies, and this article explores some of the most promising technologies that are revolutionizing the water treatment sector, including:

• software solutions,

• nanotechnology,

• biotechnology.

It also examines the advantages and challenges associated with these technologies and the opportunities and obstacles to their widespread adoption and implementation.

Current Water Treatment Techniques

The uncontrolled release of untreated sewage, agricultural runoff, and industrial waste has resulted in water quality degradation and contamination of water resources globally, with 80% of wastewater flowing back into the ecosystem without adequate treatment and around 50% without any treatment.

Wastewater refers to any used water from homes, businesses, industries, and agriculture. It also includes stormwater and groundwater that enter the sewer system. Wastewater can go through the sewage system or can be treated on-site. Depending on the origin and the contaminants present, wastewater can be categorized into four main types: greywater (from showers, washing machines, and kitchens), blackwater (e.g. toilet waste), sewage (a mixture of greywater, blackwater, and trade waste), and industrial water, which can have varying pollutant composition and concentrations depending on industry size and type.

Different treatment steps are applied depending on the contamination level and the water’s intended post-treatment use. Primary and secondary wastewater treatments are always used in conventional wastewater treatment plants.

Primary (mechanical) treatment eliminates suspended particles from water by passing them through a mesh filter or cartridge that captures them on the surface or within the filter. Mechanical water filters are designed to remove larger suspended materials from water, such as sand, silt, clay, loose scale, and organic matter. However, they are ineffective in removing dissolved chemicals or very small particles from the water.

Secondary (biological) treatment uses microorganisms to degrade organic waste in water, such as carbohydrates, proteins, fats, and other contaminants, such as some pesticides or pharmaceuticals that can be degraded by bacteria via different pathways. This process, involving bacteria and other small organisms, aims to collect decomposition results for disposal. The treatment can be aerobic (with oxygen) or anaerobic (without oxygen), both optimized for organic substance removal from wastewater.

Tertiary treatment is an advanced stage of wastewater treatment that is optional and applied only when high water quality standards need to be met, such as when water is intended for reuse, recycling, or discharge into delicate ecosystems. It includes the following techniques:

• Chemical treatment removes impurities such as bacteria, viruses, and organic matter from water. This process, applicable to drinking water, industrial processes, and more, employs chemicals like chlorine, ozone, and coagulants. The treatment method and chemical quantities depend on the contaminants and desired treatment level and are closely monitored for health and environmental safety.

• Other advanced treatment techniques are often the focus of innovative technologies for water treatment and target micropollutants. It is the final step in water purification that aims to remove remaining contaminants for safe reuse or discharge. It employs processes like reverse osmosis for mineral removal and deionization, membrane filtration for clean drinking water, water oxidation to separate hydrogen and oxygen, and UV disinfection to eliminate bacteria and viruses. This method is crucial for treating wastewater and seawater and converting it into drinkable water. Reverse osmosis and multistage flash distillation are also commonly used in desalination plants.

Shift towards more sustainable water treatment practices

Primary, Secondary, and Tertiary treatments for removing contamination from wastewater often rely on energy- and chemical-intensive processes, which are costly and not sustainable for a growing global population and increased focus on climate-friendly solutions. Two main avenues are being explored to create more sustainable, circular-economy-based wastewater treatment systems.

The first is through direct innovation and implementation of energy- and resource-efficient wastewater treatment systems. The second combines pollutant removal schemes with the generation of additional revenue streams through valuable material recovery or energy generation.

Within these two pathways, software- and hardware-based are the two main approaches to improving the status quo among water treatment plants.

Software-based solutions

The need for digitalization in wastewater treatment is clear, yet the extent of it varies widely among plants, ranging from manual sampling to AI and digital twin-infused controls. Approximately one-third of US water and wastewater management personnel will be eligible for retirement by 2028, with a similar trend in Europe. This could lead to potential labor shortages, necessitating automation efforts and an increased push to incentivize younger workers to incorporate technology into their processes.

Examples of software-based methods to improve the efficiency of water treatment plants comprise:

• Continuous monitoring optimizes plant performance by promptly reacting to changes in water quality, flow rates, and treatment performance. CertusBio, for instance, provides fully automated, self-calibrating lab-on-a-chip biosensors for continuous monitoring of food industry wastewater treatment, allowing the plants to identify wastewater content and adjust treatment processes accordingly. Sensmet is another example of a cloud-based platform for continuous monitoring of battery-relevant metals during wastewater treatment. Aquacorp, on the other hand, provides another monitoring alternative through the combination of multiparametric probes with IoT and computer vision.

• Machine Learning (ML) and Artificial Intelligence (AI)-driven process optimization can potentially make wastewater treatment significantly more cost-effective, energy-efficient, and environmentally friendly. CreaTech360 offers an operational intelligence platform focused on optimizing the energy and chemical efficiency of wastewater treatment processes. Varuna, on the other hand, apart from water quality measurement, leverages ML and AI-based sensors to predict possible issues with water quality and generate up-to-date mandated reports in real-time.

• Digital twins are virtual replicas of physical systems that use real-time data to visualize the treatment process, improving the understanding of system dynamics and performance. There has been an increasing interest in digital twins in this sector across the globe, owing to their holistic and cross-cutting vision. Pani is an example of a company that uses digital twin technology as part of its platform for water treatment plants to improve their efficiency and sustainability. Another example of a digital twin is Streamwise D.I., which creates a virtual replica of the treatment plant and uses advanced analytics and optimization algorithms. Infelliflux Controls develops automation retrofits that are implemented in existing plants and serve as virtual operator assistants and digital twins, allowing for the optimization of individual processes, providing performance reports, and adjusting cleaning protocols.

Micropollutant capture and hardware-based solutions

Numerous new approaches and technologies are being deployed to treat micropollutants, each suitable for specific pollutants or sectors. Each technology has its advantages, drawbacks, and varying levels of technological maturity. However, before delving into these technologies, it’s crucial to understand the impact of different micropollutants on human health and the environment.

Micropollutants are by-products of various processes, including industrial chemicals, pharmaceuticals, cosmetic products, pesticides, and hormones, released into the environment in low concentrations. Despite their low levels, they can accumulate in organisms due to slow biodegradation, causing ecosystem disruptions and harming living organisms. To mitigate impacts on human and aquatic health, it is essential to understand these exposures better and develop new prevention and remediation approaches.

However, treating micropollutants in wastewater presents several challenges. Apart from their low concentrations, often in the micrograms or nanograms per liter range, their diverse sources of origin result in a wide range of chemical structures and compound properties. This makes their detection and removal difficult, often requiring tailored treatment approaches for effective capture. Additionally, micropollutants are often highly stable and resistant to conventional treatment methods, making it challenging to break them down or remove them using standard wastewater treatment processes.

New methods for capturing micropollutants often involve using novel materials and strategies that enhance their removal efficiency, selectivity, sustainability, and cost-effectiveness during the water treatment process.

Nevertheless, one of the biggest challenges in implementing new water treatment technologies is their scale-up readiness level. While there are countless micropollutant capture approaches, this article highlights some of the most important and scalable ones:

Membrane Technologies

Depending on their pore size, membrane technologies can be classified into microfiltration, ultrafiltration, nanofiltration, or reverse osmosis. The pore size determines the specificity and durability of the membranes. The primary function of a membrane is to obstruct undesirable particles from purified water. Membion integrates membrane bioreactors (MBR) with conventional wastewater filtration for the secondary treatment step, yielding an effective solution for challenging micropollutants such as per- and polyfluoroalkyl substances (PFAS), pesticides, pharmaceuticals, personal care products, and heavy metals. MBR-based wastewater treatment plants deliver improved water quality and a smaller overall footprint than conventional wastewater treatment plant solutions, allowing for higher sludge concentrations and reducing tank volumes.

Adsorption and Ion Exchange Technologies

Adsorption is a surface phenomenon where particles from a fluid are attached to the upper layer of a material, known as the adsorbent. This technique is used for water treatment to remove contaminants by adsorbing (sticking) them onto the surface. Ion exchange technologies rely on ion transfer between compounds in the treated water and the adsorbent. Ion exchange adsorbents contain functional groups that attract target ions, resulting in an ion exchange process. Adsorbents can be natural, such as zeolites, or synthetic, such as customized granular media (CGM) produced by Puraffinity, a company targeting the removal of highly challenging pollutants from contaminated water and wastewater. The novel bio-based adsorbent provides a selective capture of micropollutants, including pesticides, pharmaceuticals, and PFAS.

Advanced Oxidation Processes (AOPs)

In advanced oxidation processes (AOPs), contaminants are oxidized using various oxidants, commonly hydroxyl radicals. These radicals react with pollutants, initiating the oxidation process until all pollutants become oxidized and transformed into harmless compounds. AOPs are widely used to eliminate organic contaminants from wastewater through oxidation reactions. They can mineralize pollutants and generate non-toxic byproducts.

However, AOPs utilizing hydrogen peroxide should be carefully controlled for residual hydrogen peroxide, as it can potentially negatively affect later treatment steps and may be harmful to humans. In response to those environmental concerns, H2Nano developed a buoyant, reusable photocatalyst system that requires no additional chemicals and produces no by-products during treatment. It provides a sustainable water treatment built from scratch or retrofitted. The company offers three solutions for wastewater: advanced oxidation for hard-to-degrade compounds, capturing and treating volatile emissions, and accelerated mineral recovery through solar evaporation.

Schematic representation of H2Nano wastewater treatment using buoyant, light-activated catalyst system targeting micropollutant elimination.

Electrochemical Technologies

Electrochemical processes have become important in wastewater treatment over the last two decades. Various technologies utilize electric current to induce chemical reactions, such as electrodeposition, electrocoagulation, electrooxidation, electroreduction, and electrodialysis. An example of electrochemical treatment used by Onvector is a high-voltage plasma-based electrooxidation technology for wastewater disinfection. The company’s treatment technologies use directed energy to treat water and wastewater without the need for additional chemicals.

Hybrid Technologies

Hybrid technologies combine membrane-based processes with conventional techniques to increase the removal efficiency of pollutants from water. These hybrid processes have gained attention due to their potential for high efficiency and productivity compared to conventional techniques. They are environmentally friendly, energy-saving, and reduce operating costs. Hydroleap is an example of hybrid technology, combining electrical and membrane systems to create electrooxidation and electrocoagulation platforms for enhanced wastewater treatment. The company treats high-suspended solid, high oil, and heavy metal-contaminated wastewater. Another hybrid example is Axine, which develops wireless and remotely monitored industrial wastewater treatment systems that use catalysts and electricity to oxidize toxic organics into harmless by-product gases, generating zero waste.

Extraction of valuable resources from wastewater

Some advanced wastewater treatment systems go beyond organic carbon removal and aim to recover valuable products, generating additional revenue streams. Below are some of the key innovations in wastewater treatment that not only eliminate pollutants but also increase revenue or improve the cost-effectiveness of the treatment process.

Valuable Material Extraction

Wastewater treatment processes can extract nutrients like nitrogen, phosphorus, and potassium for agricultural purposes or use them in fertilizers. Additionally, some organic compounds present in wastewater can be recovered as value-added products. Various metals can also be recovered, including lithium, uranium, mercury, selenium, silver, iron, manganese, molybdenum, boron, calcium, antimony, cobalt, and gallium. The following processes are often used for material extraction:

Electrosorption: Selective materials recovery from wastewater can be achieved using electrosorption processes with carbonaceous and intercalation electrodes (see 1st section).

• Electrochemical Redox Processes: Electrochemical redox processes involving oxidation and reduction reactions selectively recover materials from wastewater.

• Electrochemically Induced Precipitation: Electrochemically induced precipitation can selectively precipitate and recover target compounds from wastewater.

• Gasification: Wastewater sludge gasification optimizes energy recovery through downstream processing, such as combined heat and power recovery or Fischer Tropsch synthesis for liquid fuel production.

Chemfinity shows another example of valuable material extraction by implementing ion-capture electrodialysis for water treatment and retrieval of valuable metals. The process utilizes multifunctional adsorptive membranes to capture ions and extract critical metals from waste streams, including precious metals from e-waste and wastewater, providing a new approach to critical metals mining.

An alternative approach to valuable material extraction is offered by Evove, who has developed a distinct technology for this purpose. Their technology involves a range of membranes that can be used in various processes, such as lithium extraction, water treatment for municipal and food-based sources, and the production of reusable water. Weefiner is another example of a company that focuses on removing valuable metals from mining wastewater.

Bio-based treatment

Bio-based treatment technologies rely on the use of bacteria or other microorganisms to decompose organic pollutants into harmless or volatile compounds. Techniques include algae-based treatment, anaerobic digestion of organic pollutants, and activated sludge processes that rely on aerobic bacteria. Bio-based processes are particularly efficient in removing pharmaceuticals, pesticides, and many industrial chemicals. They are highly sustainable and allow for resource recovery, as some can produce valuable by-products such as biofuels and fertilizers.

• Biogas Production in wastewater treatment is currently inefficient due to slow fermentation times and the need for large digesters. However, wastewater treatment plants can use anaerobic digestion processes to convert organic waste, such as sewage sludge, into biogas. Biogas, primarily composed of methane, can be used as a renewable energy source for electricity generation or heating, reducing energy costs.

• An alternative approach to biogas production was showcased by Wase, a developer of bio-electromethanogenic reactors that generate energy from wastewater using compact sewage and fecal sludge treatment systems for peri-urban and urban communities. The company provides a waste-to-energy event monitoring platform that enhances energy recovery from waste streams that were previously considered non-viable. The system is also capable of recovering water and nutrients to create fertilizers.

Wastewater treatment developed by Wase.

Electricity Production, allowing for generating renewable energy while treating wastewater, is a promising concept that can be achieved through electricity production from wastewater. In contrast to biogas-based electricity production, microbial fuel cells offer another way to generate electricity, such as the one used by Aquacycl. They have introduced a new approach to wastewater treatment that utilizes electricity-producing bacteria to accelerate the treatment process. These bacteria convert most waste into electrons, protons, and dissolved carbon dioxide. This eliminates the primary sludge, reduces secondary sludge, generates electricity, and yields new molecular water.

Green Hydrogen Generation can also be integrated with water treatment processes. Water from various sources, including wastewater, surface water, or municipal effluent, can be used as a feedstock for green hydrogen generation through electrolysis or other hydrogen production technologies. For example, Aquature offers a sustainable wastewater treatment management platform, promoting circularity and independence while reducing industry costs. Their bioelectrochemical technology leverages the energy of wastewater and allows for efficient purification of wastewater while simultaneously generating hydrogen at much lower production expenses. This is an interesting approach to hydrogen generation from waste streams, particularly those with high organic contents, such as the food and beverage industries.

The water treatment market sector

Global Market Size and Growth

The water treatment market is predicted to grow significantly in the coming years due to aspects such as population growth, urbanization, increasing need for new water resources, strict regulations on water quality and public health, and expanding industrial applications. According to a report by Fortune Business Insights, the global market size for water and wastewater treatment was valued at USD 301.77 billion in 2022 and is projected to reach USD 536.41 billion by 2030, with a CAGR of 7.5% during the forecast period.

The market consists of segments such as chemicals, equipment, and services catering to various applications, including municipal and industrial water treatment. Technological advancements and innovations in water treatment systems, such as real-time microbial monitoring, desalination, and membrane filtration, also influence the market.

Here are some of the key industry players in the water and wastewater treatment industry listed by revenue:

BASF — one of Europe’s largest wastewater treatment plants, primarily dedicated to biological treatment. Their largest plant is in Germany, with others in the US, China, and Malaysia.

1. Dow — Worldwide provides crucial chemical solutions for water treatment, food processing, paper manufacturing waste, metal ion capture, and more.

2. 3M — The leading global provider of materials science solutions specializing in water filtration for residential, industrial, and commercial food service applications.

3. Veolia — Multinational company that provides solutions for water and wastewater treatment, sludge treatment, water reuse, and more for both municipal and industrial clients. Their solutions cover the entire wastewater treatment cycle, ensuring the treated wastewater can be safely reused or discharged.

4. DuPont — Multinational chemical company that offers advanced wastewater treatment technologies and solutions to address crucial challenges by reducing effluent discharge, reusing wastewater, and recycling by-products.

5. Suez — Multinational company primarily focused on water and wastewater treatment solutions, operating plants across the globe. It is one of the leaders of circular solutions in water and waste through innovation. It offers a variety of solutions for wastewater treatment, including municipal and industrial wastewater treatment, sludge treatment, and water reuse.

Venture Capital Investments in Water Technologies

Venture capital investments in water technologies have also been increasing:

• In 2021, water startups across 90 countries raised an estimated $470 million.

• Between 2009 and 2017, venture and private equity growth capital investors funded 101 deals, amounting to over $704 million in water startups.

• Emerald Technology Ventures closed a $100 million water impact rund, with investments from Temasek and strategic investors such as SKion Water, Ecolab, and Microsoft.

• Below is a table summarizing the start-ups mentioned within the article by focus area.

Challenges

Some of the challenges for venture capital (VC) in water tech investments include the following:

• Public subsidies: The water sector receives significant public subsidies globally, making it difficult to attract private investments. The price of water does not reflect its value as an essential commodity.

• Slow adoption and low returns: The water tech sector is emerging, with few companies and funds. Regulatory hurdles, decision-making processes, and customer inertia contribute to the slow uptake of water solutions and low returns on investment for VC firms.

• High fragmentation and complexity: Water is used in various market segments, requiring tailored solutions for different customer needs, geographies, and regulations. This increases the complexity and cost of developing and scaling water tech solutions.

• Poor infrastructure and underfunding: Outdated and under-resourced water infrastructure, especially in developing countries, poses challenges for water tech solutions. Additionally, water is often underpriced or subsidized, reducing the incentive for customers to adopt water-saving or quality-improving technologies.

• Water as a public good: Government regulations and social/environmental considerations limit the profit potential and scalability of water technologies, particularly in developing countries where water affordability and accessibility are significant challenges.

• Conservative sector: The water industry tends to be risk-averse and capital-intensive, preferring proven and reliable solutions over disruptive and novel ones. Regulatory and financial barriers further hinder the adoption of new technologies by water utilities and end-users.

Overview & Outlook

Water technology plays a vital role in human health and innovation, driving progress in various sectors such as agriculture, energy, manufacturing, and biotechnology. Every year, an increasing number of venture capitalists recognize the potential of new water tech startups in addressing critical challenges and opportunities. The transformative power of water technology is yet to be fully realized, with ongoing advancements and applications expected. Water tech presents a wide range of opportunities for innovation. Investing in water technology is a strategic financial decision that supports global sustainability and resilience goals. The future holds promise for further advancements and expansion in water tech, creating new solutions for the betterment of humanity and the planet.

We want to hear from you!We are curious to hear your thoughts and ideas. If you’re working on Water. Treatment applications or anything related to water technologies, please reach out to us.