Measurement & Control Intelligent Sensor Management Lowers Maintenance Requirement for PH Systems
In developing countries, demand for liquid sugars is growing. For a customer in Brazil, a pH measurement solution that would tolerate the harsh process conditions was essential. Mettler Toledo provided them a robust, dependable system that requires very little maintenance.
Liquid sugars are produced in a number of different formulations for use in the Food and Beverage (F&B), and chemical industries. Premium liquid sugar is a virtually clear sucrose syrup used in the manufacture of a wide range of beverages and food products. Standard liquid sugar is a light-yellow sucrose syrup, which is used in the production of cordials and juices. Liquid sucrose can be used in many non-food applications, for example in industrial fermentation processes as a substrate.
Production of liquid sugar can be achieved by adding distilled water to dry sugar, or by processing cane juice. The production process for liquid sugar from cane juice is simpler than that of dry sugar, and it also produces a product of a more uniform quality. However, unlike the extremely long lifetime of dry sugar, liquid sugar has a shelf life of only a few weeks.
The sugar industry in Brazil has been investing heavily in liquid sugar production to meet the increasing market demand. This company, a major sugar refiner, manufactures liquid products, which are purchased mainly by soft drinks manufacturers from local producers to multi-nationals.
PH–Measurement in Sugar Refineries: Tough Conditions
The refinery’s liquid sugar production process follows the same initial steps to that of dry sugar, namely: juice extraction, filtration, sulphitation and liming. pH measurement during sulphitation and liming is essential as the pH level in the first stage determines the quantity of sulphur dioxide (SO2) that must be added to the juice to prevent discolouration of the liquor.
The purpose of adding slaked lime is to increase the pH of the acidic sulphated liquor from approx three to seven. The high concentration of sugar in the juice and the addition of other chemical products – make it very difficult to measure pH during these processes, as electrodes can become easily coated in precipitates. In order to maximise production uptime, the company was looking for a pH measurement system, which would endure the process conditions, without requiring a great deal of maintenance.