With the cost-sensitive nature of sugar production, successful manufacturing demands a high level of automation and precise control over process parameters. This in turn leads to time savings and increased output.
Pressure, temperature, and flow products (transmitters and switches) are vital elements of food manufacturing, especially in the sugar industry.
Delta Mobrey’s dependable, easy-to-clean, and innovative technologies guarantee high plant availability, and reduce the risk of equipment damage during maintenance. Fig 1 shows a typical Sugar production process using sugar cane and beet.
Figure 1: Sugar production from sugar cane/beet
At various stages during sugar production, process instrumentations are required for measuring and control purposes. A typical application of Pressure (P), Temperature (T), Flow(F)/Level (L) (using DP) instrumentation is shown in Fig 2.
Figure 2: Use of P, T, and Flow/Level (DP) in sugar production (evaporation and crystallisation stages)
Differential pressure measurement
Differential pressure systems in evaporators are often damaged because of harsh production environments and cleaning processes. A diaphragm seal, with extended diaphragm and direct diaphragm cleaning system, will alleviate this problem; examples of instrument configurations are shown below.
The transmitter with a direct diaphragm seal (connected to the positive measurement chamber) and a remote diaphragm seal (connected to the negative chamber) is recommended for hydrostatic measurements of levels, densities, phase boundaries, and pressure differences (with differentiated height of pulse source points). In such a configuration, at ambient temperature changes, two opposite phenomena appear concurrently.
Thermal expansion causes the change in the volume, and hence density, of the manometric fluid in the capillary, resulting in a change of the hydrostatic pressure related to the vertical spacing of the seals.
This phenomenon is counteracted by the elastic reaction of the diaphragm of the upper diaphragm seal, which is displaced by the change in volume of manometric fluid.
Based on tests and experiments, the Delta Mobrey transmitters come with carefully selected diaphragm seals, guaranteeing compensation of errors resulting from ambient temperature changes.
Our special design of extended diaphragm seals (e.g. S-TK–DN100/T=100mm) come with an additional diaphragm cleaning system. D-series transmitters with diaphragm seals provide accurate and reliable performance for the measurement of highly viscous mediums, typical of sugar production. A cleaning system allows membrane cleaning without having to remove the diaphragm seal from the application.
A cleaning medium (e.g. water) is supplied to the membrane surface via two flushing ports located externally to the diaphragm seal for easy access. The adjacent figure shows the application of such a design.
Temperature measurement and control
Temperature is of particular importance to improving the sucrose extraction process, for which imbibition water is applied.
This process consists of adding water to the pulp before it passes through the final mill, increasing sucrose extraction by approximately 15%. Higher the imbibition temperature, higher the extraction rate.
Delta Mobrey temperature transmitters DPT-2000ALW and D72 models are used in various applications across the industrial sectors. Both models come with a field mounting head and Hart communication protocol.
D72 models have a large variety of direct and remote sensing options, materials, and process connections, providing a high level of flexibility, and making them suitable for a wide variety of applications.
Level and density measurement
Within the clarifiers used for cane sugar production, a measurement of the density of undissolved solids will help operators to assess the performance. The MSM400 controller and ultrasonic gap sensor (see left) will give a continuous measurement of the liquid density in terms of percentage of undissolved solids, helping operators make decisions about what process parameter should be checked and adjusted.
Sensors are available for either tank mount, or fitted within pipe sections for easy installation within pumped pipe-work.
The MSM400 could also have applications in factory syrup and refinery liquor clarifiers, where in some cases instrumentation is used to monitor flocculant formation at the outlet of the clarifier weir-box.
Rather than directly controlling any process variables, the density measurement may be used to recirculate syrup or liquor if flocculant formation goes too high, indicating a problem in the process.
For bulk silos holding beet or cane, and those storing the end sugar product, dry solids level switches provide a means of inventory control. The vibrating level switch (VLS) and paddle level switch (PLS) positioned at appropriate points within a silo will give high or low-level indications.
During internal transport within the plant, prior to mixing into a juice, the same switches can also be used on hoppers to detect product and warn of any blockages.
For water/storage tank applications the Delta Mobrey mechanical float switch can be used for either high or low-level alarm or pump control duties.
These instruments, with their tough, rugged, and proven design, are suitable for use in most environments and trusted globally for their long-term reliability.
The magnetically coupled design means there are no glands or linkages, preventing the risk of leaks. Our snap-acting switch produces a clean make-or-break contact with no hover or bounce and, with a high resistance to vibration, false trips are eliminated.
The Delta Mobrey mechanical float switch also offers dual redundancy for use in conjunction with our Hydrastep remote level indicator (see further below) for boiler steam drum level measurement applications.
Sugar refining processes demand a high level of heat and energy. Water tube boilers drive generators to give electrical power, and the exhaust steam is used throughout the plant for the heating processes. Hydrastep is often used as a remote level indicator for the boiler steam drum level measurement.
Using conductivity probe technology, Hydrastep can interface with a DCS to provide level measurement and alarms, and also offers a separate remote display for the boiler house CCR. A typical system as used on the steam drum is shown in the adjacent image. Hydratect provides a means of detecting any water in steam lines to protect against turbine damage.
Along with, the wide portfolio of products, Delta Mobrey has a reputation of developing solutions in collaboration with customers to suit their specific needs. Please get in touch.
About Delta Mobrey
For more than 100 years, Delta Mobrey Limited has been a world-leading specialist in the design and manufacture of quality process instrumentation for the measurement and control of fluids and gases in all industrial plant and equipment.
Trusted quality – proven value: quality and reliability have always formed the cornerstone of our success, recognised by industry with international approvals covering every aspect of our manufacturing and product portfolio, together with certifications spanning all areas of hazardous and regulated environments.
Global team – local support: as a global organisation, Delta Mobrey is totally committed to delivering the best possible customer service and technical support, ensuring a lifetime value of ownership, together with a flexible and responsive approach to meet our customers’ individual demands