Against the backdrop of worsening global water scarcity and water pollution, sewage treatment enterprises, as the core carriers of water environment governance, shoulder the important mission of purifying sewage, protecting water resources, and facilitating the sustainable development of ecosystems. With the advancement of the "dual carbon" goals and the release of policy dividends such as the revision of the Water Pollution Prevention and Control Law, sewage treatment enterprises have not only become the backbone of the environmental protection industry but also are steadily moving toward the direction of technological intelligence, treatment resource utilization, and low-carbon operation, driven by both policy guidance and market demand. This article will comprehensively analyze the value and development logic of sewage treatment enterprises from dimensions including core mission, technological system, industry status quo, development trends, and selection criteria.​

I. Core Mission of Sewage Treatment Enterprises: "Guardians" of Water Environment Governance​

The core value of sewage treatment enterprises lies in efficiently treating pollutants such as industrial wastewater and domestic sewage through professional technologies and systematic services, enabling them to meet national discharge standards before being discharged or to realize resource utilization, thereby curbing the spread of water pollution at the source.​

• Responding to Environmental Protection Policy Requirements: Strictly abide by laws and regulations such as the Water Pollution Prevention and Control Law of the People's Republic of China and Discharge Standards of Pollutants for Municipal Wastewater Treatment Plants, implement policy arrangements including the "Ten Measures for Water" and the "14th Five-Year Plan for Ecological and Environmental Protection", ensure that sewage meets discharge standards, and contribute to the improvement of regional water environment quality.​

• Guaranteeing Water Resource Circulation: Through sewage purification and reclaimed water reuse technologies, the treated water resources are used in fields such as industrial production, urban greening, and municipal sanitation, alleviating the contradiction between water supply and demand and promoting the construction of a "water-saving society".​

• Reducing Environmental and Ecological Risks: For refractory sewage such as high-concentration organic wastewater and heavy metal wastewater, customized treatment solutions are adopted to reduce the damage of pollutants to soil, groundwater, rivers, and lakes, and protect the balance of aquatic ecosystems.​

II. Core Technological System of Sewage Treatment Enterprises: Full-Process Solutions from Purification to Resource Utilization​

A professional technological system is the core competitiveness of sewage treatment enterprises, covering all links such as sewage collection, pretreatment, main treatment, advanced treatment, sludge disposal, and resource utilization. Different scenarios correspond to differentiated technical paths:​

1. Basic Treatment Technologies: Building the First Line of Defense for Sewage Purification​

• Physical Treatment Technologies: Using equipment such as grids, grit chambers, and sedimentation tanks to remove large-particle impurities such as suspended solids and sand in sewage, reducing the subsequent treatment load. They are commonly used in the pretreatment of domestic sewage and the primary treatment of industrial wastewater.​

• Chemical Treatment Technologies: Adopting processes such as coagulation, flocculation, and redox to remove soluble pollutants and heavy metal ions in sewage. They are suitable for the enhanced treatment of high-concentration industrial wastewater (e.g., electroplating wastewater, chemical wastewater).​

2. Core Treatment Technologies: Realizing In-Depth Degradation of Pollutants​

• Biological Treatment Technologies: The mainstream processes include the activated sludge process, biofilm process, and anaerobic digestion technology. These technologies use the metabolic function of microorganisms to decompose organic pollutants in sewage, featuring low cost and strong environmental friendliness. They are widely used in the treatment of municipal domestic sewage and low-concentration industrial wastewater.​

• Membrane Separation Technologies: Represented by MBR (Membrane Bioreactor) and RO (Reverse Osmosis), these technologies realize solid-liquid separation through the interception function of membranes. The treated water quality can meet reuse standards, making them the core technologies for high-end industrial wastewater treatment and reclaimed water reuse projects.​

3. Resource Utilization Technologies: Promoting the Transformation of Sewage into "Treasures"​

• Reclaimed Water Reuse System: Through processes such as advanced filtration and disinfection, the treated sewage is converted into reclaimed water, which is used for industrial cooling, agricultural irrigation, and urban landscape water replenishment, realizing the circular utilization of water resources.​

• Sludge Resource Utilization: Technologies such as anaerobic fermentation, drying and incineration, and composting are adopted to convert sludge generated from sewage treatment into biogas (for energy utilization), organic fertilizer (for agricultural application), or building materials (for resource utilization), reducing the pressure of solid waste disposal.​

• Pollutant Recovery: Recovering resources such as heavy metals and organic solvents from high-concentration industrial wastewater, e.g., recovering precious metals like copper and nickel from electroplating wastewater, achieving a win-win situation of "pollution control + income generation".​

III. Industry Status Quo of Sewage Treatment Enterprises: Dual Empowerment from Policy Drive and Market Demand​

1. Industry Development Opportunities​

• Increased Policy Support: The state continues to promote the construction of "Beautiful China", and local governments have introduced policies such as subsidies for the construction of sewage treatment facilities and tax incentives, promoting the upgrading and transformation of municipal wastewater treatment plants and the implementation of centralized industrial wastewater treatment projects.​

• Sustained Growth in Market Demand: With the acceleration of industrialization and urbanization, the discharge of industrial wastewater increases year by year, the rural sewage treatment market is gradually opening up, and the demand for the renewal and replacement of old sewage treatment facilities provides a broad market space for sewage treatment enterprises.​

• Urgent Need for Technological Upgrading: Environmental protection standards are constantly improving (e.g., the discharge standard of municipal wastewater treatment plants has been upgraded from Grade B to Grade A), forcing sewage treatment enterprises to upgrade their technical processes. Intelligent and low-carbon technologies have become the focus of market competition.​

2. Industry Challenges​

• Significant Cost Pressure: Sewage treatment projects require large upfront investment and high operating costs (energy consumption, chemicals, labor), and some small and medium-sized enterprises face difficulties in capital turnover.​

• Serious Technological Homogenization: The competition in the medium and low-end sewage treatment market is fierce. Some enterprises lack core technologies and rely on traditional processes, making it difficult to meet the needs of high-difficulty sewage treatment.​

• Room for Improvement in Resource Utilization Level: At present, the reuse rate of reclaimed water in China is less than 30%, and the sludge resource utilization rate is low, which is still far from that of developed countries, leaving much room for improvement in the industry.​

IV. Future Development Trends of Sewage Treatment Enterprises: Intelligence, Resource Utilization, and Low-Carbonization​

1. Intelligent Operation Becomes Mainstream​

With the help of technologies such as the Internet of Things (IoT), big data, and artificial intelligence (AI), "smart sewage treatment plants" will be built to realize functions such as equipment operation monitoring, real-time water quality detection, and automatic adjustment of process parameters, reducing labor costs and improving treatment efficiency. For example, sensors collect data such as sewage pH value and COD concentration, and the AI system automatically optimizes the aeration and chemical dosing processes to reduce energy consumption and chemical usage.​

2. In-Depth Expansion of Resource Utilization​

In the future, sewage treatment enterprises will transform from "single purification" to "resource circulation", focusing on the development of businesses such as reclaimed water reuse, sludge resource utilization, and energy recovery (e.g., using sewage waste heat for heating and photovoltaic panels for power generation in the plant area), and building a circular economy model of "sewage - reclaimed water - sludge - energy".​

3. Accelerated Low-Carbon Transformation​

In response to the "dual carbon" goals, sewage treatment enterprises will reduce carbon emissions during operation by optimizing processes (e.g., adopting low-energy biological treatment technologies), using clean energy (photovoltaics, wind power), and applying carbon capture technologies. Some enterprises have begun to explore the construction of "carbon-neutral sewage treatment plants".​

4. Professional Development in Segmented Fields​

For segmented scenarios such as industrial wastewater (chemical, pharmaceutical, electronics, printing and dyeing, etc.), rural sewage, and black and odorous water treatment, sewage treatment enterprises will focus on the R&D of specialized technologies and provide customized solutions. Professional competition in segmented fields will become an industry trend.​

V. How to Select a High-Quality Sewage Treatment Enterprise? Reference for Key Indicators​

In water environment governance projects, selecting a professional and reliable sewage treatment enterprise is crucial to ensuring treatment effects and controlling costs. The following 5 points should be focused on:​

• Qualification Certification: Possessing qualifications such as environmental protection engineering professional contracting qualification, sewage treatment operation qualification, and ISO environmental management system certification to ensure that the enterprise complies with industry standards.​

• Technological Strength: Whether it has core technology patents and a professional R&D team, and whether it can provide customized treatment solutions for different types of sewage, especially the ability to treat high-difficulty industrial wastewater.​

• Project Experience: Checking the enterprise's past project cases (e.g., the construction of municipal wastewater treatment plants, EPC projects for industrial wastewater treatment) to understand the actual situation such as project scale, treatment standards, and operation effects.​

• Service System: Whether it provides full-process services from project design, equipment installation, commissioning and operation to later operation and maintenance to ensure the long-term stable operation of the project.​

• Environmental Compliance: Whether the enterprise's own operation complies with environmental protection requirements, whether there are records of environmental penalties, and whether the discharged sewage and sludge after treatment meet the standards.​

Conclusion: Sewage Treatment Enterprises Contribute to the Sustainable Development of the Ecological Environment​

As the core force in water environment governance, sewage treatment enterprises are not only practitioners of environmental protection policies but also promoters of the circular utilization of water resources. Driven by both policy support and market demand, with technological innovation and model upgrading, sewage treatment enterprises will gradually achieve the multiple goals of "sewage purification, resource recovery, and energy consumption reduction", providing solid support for the implementation of the concept that "lucid waters and lush mountains are invaluable assets".