Temperature & pH Probes

The Temperature & pH Probes are a critical instrumentation component of a neutralization reactor, consisting of a combined or co-located temperature sensor and pH electrode. They provide real-time, in-situ measurements of both thermal conditions and acidity/alkalinity (pH) of the reaction mixture, enabling precise process control for achieving target neutralization endpoints, optimizing reaction kinetics, and ensuring product quality and safety. The temperature probe (typically a thermocouple or RTD) measures the thermal energy of the solution, converting it into an electrical signal. The pH probe measures the hydrogen ion activity via a glass electrode, generating a millivolt potential proportional to pH. Both signals are transmitted to a controller or data acquisition system for monitoring and automated adjustment of reactor conditions (e.g., heating/cooling, reagent dosing). The assembly is housed in a stainless steel (316L) sheath, with a pH-sensitive glass membrane and a reference electrode fill solution (e.g., KCl). The temperature sensing element can be thermocouple wires (Type J/K) or an RTD element (Platinum). The probes are designed for a pH measuring range of 0–14, temperature range of -10–130 °C, with accuracies of ±0.02 pH and ±0.1 °C (Class A RTD). Response times are ≤10 s (pH) and ≤5 s (temperature). Operating pressure is 1.0–1.6 MPa, and ingress protection is IP65–IP68 (IEC 60529). Supply voltage is 24 ±10% V DC, with a 4–20 mA output signal (HART optional). Wetted materials are 316L/PTFE (ASTM A276), process connection is 1/2–1 inch NPT (ASME B1.20.1), and weight ranges from 0.5–1.5 kg depending on insertion length. These values are directory references and must be verified with the legal manufacturer or supplier for the specific model and application. The probes are suitable for continuous operation in typical reactor conditions. For selection, consider the required measuring ranges, accuracy, response time, process connection, and environmental conditions. Verification questions should include confirming the exact materials, pressure rating, and compatibility with the process media. Maintenance signals include slow response, drift, or erratic readings, indicating possible fouling or electrode degradation. Failure boundaries include exceeding the specified temperature or pressure limits, which can damage the sensor. Always consult the manufacturer's documentation for installation, calibration, and maintenance procedures.

The temperature probe (typically a thermocouple or RTD) measures the thermal energy of the solution, converting it into an electrical signal. The pH probe measures the hydrogen ion activity via a glass electrode, generating a millivolt potential proportional to pH. Both signals are transmitted to a controller or data acquisition system for monitoring and automated adjustment of reactor conditions (e.g., heating/cooling, reagent dosing).