Real-time, Continuous and Mobile pH Measurement - METTLER TOLEDO

Real-time, Continuous and Mobile pH Measurement

APIpH measurement using grab samples is slow, time-consuming and can lead to production delays. In-line pH systems provide continuous, real-time data. A UK API producer required more than in-line measurement – they wanted a mobile system.

Our customer, one of the world’s largest pharmaceutical companies, has a regional research and development base in the UK. This includes a pilot plant facility that concentrates on APIs via chemical synthesis.

Work carried out on the site involves leading an API from development work, through clinical trials to the ultimate goal of taking the product to market.

Delay in measurement
The customer has more than 20 vessels of varying capacity that are used for development chemistry projects. Depending on the composition and synthesis steps involved, measurement of pH is an important consideration for many of the reactions. In the past, pH measurement had been achieved by taking grab samples from the process and measuring them using a laboratory pH meter. This practice was inefficient as the time taken to obtain pH readings led to delays in making additions to achieve the target pH. This ultimately led to longer batch times and created delays in the tight schedule of project throughput of the plant.

Importance of flexibility

In order to improve pH measurement during pilot plant projects, our customer discussed with METTLER TOLEDO technicians the possibility of measuring pH in-line with a mobile unit. Our customer was looking to achieve a reliable pH measurement in a potentially wide range of chemistry projects.

The goal was to use pH systems to control dosing pumps to achieve a specific setpoint. Flexibility was another key to the success of the installation as the unit would only be utilized effectively if it could operate on the majority of the vessels in the pilot plant.

Flexible and robust solution

METTLER TOLEDO suggested using an InPro 4800 pH electrode in combination with an InFit 763e housing and M700 transmitter. The housing allows the pH sensor to access the majority of the vessels using a flange connection.

The InPro 4800 electrode’s record as a top of the line combination pH and temperature sensor means that it has been designed to handle high pressure and temperature applications and has a strong resistance to oxidizing media, solvents and acid / alkali solutions.

The M700 transmitter, which completes the measurement system, was installed with a PID module that controls two dosing pumps to facilitate neutralization reactions.

The pH equipment including dosing pumps was located on a mobile skid that can be moved to any part of the plant when required. As all of the components of the system are ATEX rated we achieved the customer’s expectation of a fully flexible pH measurement system that is extremely easy to use.

There has been such a high demand for use of the mobile pH system among chemists working on a variety of projects, that an order has been placed for a second system to work alongside the existing unit.

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