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In the chemical industry, analytical samples often contain high-temperature, high-pressure, high-salinity, organic solvent, acid, and alkali corrosion characteristics. These conditions make it impossible for analytical instruments to measure samples directly, so pretreatment is required.
Dongrun can provide customers with complete technical solutions, covering on-site sampling analysis, accurate instrument selection, R&D and design, integrated manufacturing, installation and commissioning, and operation and maintenance.
Scenario Description
Chemical industry operating conditions are complex and maintenance is difficult. When samples contain large amounts of suspended solids and particulates, filters are prone to clogging and require regular cleaning. Manual cleaning is time-consuming and labor-intensive.
Dongrun’s self-developed self-cleaning system does not require disassembly. During the cleaning process, the signal is locked. After cleaning, the sensor is automatically re-immersed in water and resumes measurement. This reduces manual workload and makes maintenance more convenient and efficient.
Solutions
1. Automatic Gas Cleaning
Automatic gas cleaning is mostly used for cleaning oil-in-water sensors, and can also be used for back-blowing filters in pretreatment systems. It consists of ball valves, gas filter pressure reducing valves, solenoid valves, check valves, stainless steel tube fittings, and related accessories. The structure and control system are mature and reliable.
2. Automatic Liquid Cleaning
Automatic liquid cleaning is mostly used in wastewater pretreatment systems. When suspended solids and particulates are high and filters are prone to clogging, automatic water cleaning can be used. Customers only need to connect one cleaning water line. The system consists of ball valves, pneumatic ball valves, check valves, and related accessories, ensuring stable and reliable operation.
3. Combined Gas + Liquid Cleaning
For samples containing sludge, a combined gas sweeping and water cleaning method is used. First, the filter is swept with gas, then backwashed with cleaning water, and finally the pipeline and filter are purged with gas again. This ensures that the sample detection data remains accurate when measurement resumes.
Customer Case — Wanhua Chemical
pH Measurement in a PC Wastewater Acid-Base Neutralization Tank Under Complex Conditions
1. Customer Background and Challenges
(1) The PC wastewater at this Wanhua project contained a large amount of process materials. During pH adjustment, bisphenol A precipitated in large quantities and caused serious fouling of the pH electrode. Simple water washing was not effective, while pH value was critical for neutralization control and had interlock functions.
(2) Wanhua originally required manual electrode removal and cleaning twice a day, which was time-consuming, labor-intensive, and generated high maintenance costs.
2. Solution
Dongrun exclusively designed a chemical reagent self-cleaning system. The electrode is automatically lifted above the liquid level at regular intervals, then cleaned automatically with chemical reagents and water. The signal is locked during cleaning. After cleaning, the electrode is automatically re-immersed in water to resume measurement.
3. Value Delivered
After commissioning, automatic cleaning under normal operating conditions met the measurement requirements. Only one manual cleaning was required every half month, which significantly reduced maintenance workload.
To learn more about our products and services, please click the link and get in touch with us.https://www.dongrun-instrument.com/
