In modern wastewater treatment and resource recycling systems, retention tanks play a pivotal role. They not only regulate water flow and balance peak and off-peak demands but also serve as essential preliminary or critical stages for many advanced purification processes. However, these relatively enclosed spaces with complex water compositions often harbour persistent concerns. Among these, the presence of ammonia (NH₃) and hydrogen sulphide (H₂S) warrants particular attention.

　　While ammonia emits a pungent odour at low concentrations, elevated levels not only jeopardise human health but may also disrupt subsequent treatment processes. Hydrogen sulphide, with its characteristic ‘rotten egg’ smell and potent corrosive and toxic properties, poses a significant latent threat to both the storage basin and its surrounding environment. These gases typically arise from the decomposition of organic matter under anaerobic or hypoxic conditions. Their concentrations fluctuate not only with variations in influent quality and volume but also exhibit gradient differences across different zones within the basin. Concurrently, temperature variations within the basin—a critical factor influencing chemical reaction rates and microbial activity—indirectly governs the generation and transformation rates of ammonia and hydrogen sulphide. Consequently, real-time, precise, and granular monitoring of these three pivotal parameters—ammonia and hydrogen sulphide concentrations alongside temperature—is not merely a superficial compliance measure for environmental regulation. It represents an intrinsic necessity for comprehending the basin's biochemical processes, evaluating operational status, and anticipating potential risks.

　　For the client, having invested substantially in developing and deploying an innovative system designed to efficiently purify harmful gases within the storage tank, the core objective is to significantly reduce ammonia and hydrogen sulphide emission concentrations. However, the value of any technological innovation must ultimately be substantiated by rigorous data. The client urgently required a reliable monitoring system capable of delivering legally valid and scientifically persuasive data. This data must quantitatively demonstrate the purification efficacy of their equipment against hydrogen sulphide and ammonia under real operating conditions, with precision to two decimal places. Such accuracy is essential to reflect both the significance of the results and the sophistication of the technology.

　　Against this backdrop, the Yiyun Weather online gas monitoring system emerged, bearing high expectations as the pivotal tool for validating the client's equipment performance and mapping purification outcomes.

　　1. Project Background

　　Keywords: Retention tank, hydrogen sulphide, ammonia, temperature

　　Monitor ammonia, hydrogen sulphide, and temperature within the retention tank.

　　Ambient temperature, high humidity (gas drawn from the storage tank contains moisture), atmospheric pressure, dust-free environment.

　　H₂S: 0-25 PPM

　　NH₃: 0-25 PPM

　　Temperature: -40℃ to +120℃ (actual gas temperature is ambient)

　　Purpose: To demonstrate the effectiveness of the client's own equipment in purifying hydrogen sulphide and ammonia. Results to be displayed to two decimal places.

　　2. Solution

　　Employ simplified pre-treatment equipment to filter moisture from the gas prior to concentration detection.

　　Pump-suction method: gas drawn from the storage tank via piping for analysis.

　　Product housed outdoors with stainless steel enclosure, IP67 protection rating.

　　3. Product Specifications

　　Model: TH1000-B-YP

　　Detected Gases: Ammonia NH₃, Hydrogen Sulphide H₂S, Temperature

　　Detection Range/Resolution/Principle:

　　NH₃: 0-25 PPM, 0.01 PPM, electrochemical sensor, resistant to H₂S interference;

　　H₂S: 0-25 PPM, 0.01 PPM, electrochemical sensor;

　　Temperature: -40°C to +70°C, 0.1°C, capacitive sensor;

　　Includes instrument enclosure, material S304, thickness no less than 1.5mm.

　　Features 10-metre flexible hose for duct and instrument connection,

　　Equipped with NPT 1/4-8 fitting (S304).

　　Instrument protection rating: IP67.

　　4. Site Photographs

　　The successful implementation and stable operation of the Yiyun Weather online gas monitoring system has opened a new window for studying gas behaviour within the complex aquatic environment of the regulating reservoir. It is not merely a set of cold, impersonal instruments, but rather a technical endorsement of the client's confidence in the efficacy of their independently developed purification equipment. As the system continuously and reliably outputs ammonia and hydrogen sulphide concentration data accurate to two decimal places while simultaneously recording minute temperature fluctuations, these figures hold immense value.

　　The Yiyun Weather gas monitoring system clearly charts the purification equipment's performance within the specific application scenario of the storage reservoir. It unequivocally demonstrates that hydrogen sulphide and ammonia concentrations achieve the substantial reductions claimed by the client following treatment. These precise measurements provide irrefutable proof of the purification process's authenticity and efficacy. These high-precision data points not only fulfil the client's need to demonstrate technological leadership to the industry and regulatory bodies. More importantly, the Yiyun Tian system has distilled invaluable operational insights, providing scientific grounds for future optimisation of equipment parameters and enhancement of overall treatment efficiency.

　　Indeed, the deployment of the Yiyun Tian online monitoring system has not only quantified the value of the client's product but also propelled the operation and maintenance of storage reservoirs towards greater precision and intelligence. Like a precise measuring rod, it quantifies the pace of technological advancement while providing robust, reliable data support for constructing safer, more environmentally sustainable urban water infrastructure.

　　Looking ahead, as monitoring technologies continue to evolve and application scenarios deepen, Yiyun Tian's online monitoring system will undoubtedly play an indispensable role across broader domains, continually writing new chapters in safeguarding the environment and validating operational efficacy.