Thanks to its stable energy-saving capabilities, major upgrades in the control of the two large wind turbines have increased production capacity and the investment can be recovered within one year. Two modular Unidirve SPM AC drives from Emerson CT generate significant energy savings and deliver returns in the shortest possible time.
Located at the Civil and Marine Middlesbrough plant on the coast, adjacent to the Corus Steel Plant. Blast furnace slag, and waste products from other steel plants, form a fine powder called GGBS. These fine powders can improve the performance of concrete and can replace 20%-80% of ordinary cement.
In particular, excessive dampening and damage of the damper drove the test of an alternative method of air flow control, which extracts highly ground fine powder from a ball mill and Sepol separator in Civil and Marine's GGBS Grinding Plant. "Because there is no fan running at full speed, there is an opportunity for 'energy saving'," said Rob Thwaites, electrical engineer and assistant engineering manager. “We introduced Emerson CT, the device can calculate possible savings and predict that the Sepol splitter drive can be rewarded in just 7 months, and the ball mill can be rewarded in September. The results prove that Emerson CT calculations are complete Correctly, the savings we have achieved are exactly the same as those expected by Emerson.
The Sepol separator is driven by a 200kW motor at full speed from 71% to 75%. When using the damper, the energy consumption is 146 kWh. With variable frequency drive control, energy consumption has been reduced to 61 kWh, saving 85 kWh. The roller is driven by a 160kW motor.
The main advantage
Return in 7-9 months
Improve productivity
Energy efficient
Accurately predict recovery costs
Noise reduction
Reduced maintenance costs
The power consumption is 105kWh and the air flow rate is limited to 50%. This has been reduced to 45 kWh and this machine has saved 60 kWh. With a production time of more than 100 hours per week, the total savings are 145 kWh, which means savings of more than £700 a week for electricity – every week!
The actuators recommended by Emerson CT are the 200kW and 132kW modular Unidrive SPM drives, which were adapted by the Rob Thwaites team to the existing structure. The modular features of the driver power circuit are suitable for non-standard enclosures, while providing a full range of standard and optional feature types with the proven and popular Undrive SP series and compatibility with the same debug and programming software tools. The Unidrive SPM is versatile and can be configured for open-loop and closed-loop modes, with the same load parallel output, active input and regenerative feedback, multi-pulse configuration (12, 18, 24, etc.) or to provide common dc between inverters Busbars.
Both drives are speed controlled via a single PLC.
“Another benefit that we did not anticipate was the reduction of noise,†Rob Thwaite commented. “This makes the work environment of the employees more comfortable. We also predicted that the fan motor and bearing life would be extended and maintenance costs reduced.â€
In addition, Emerson CT Unidrive SP AC drives have been installed in two 450kW pre-grinding machines with four modules in parallel mode. The role of the newly added part is to mix coarse spheroidal particles with GGBS particles. The application of this part has increased the overall production volume from 50 tons per hour to 70 tons. The transformation improved the energy efficiency of the plant by reducing energy consumption per ton of output.
Civil and Marine specializes in the production of GGBS in six factories, two plants in the United Kingdom and a factory in the Czech Republic. GGBS is one of the most environmentally friendly building materials. It uses less energy and emits less carbon dioxide than one-fifth that of the port and cement industry. (The carbon dioxide emissions of the port and cement industries are estimated to be approximately 5 of the global total. %). GGBS concrete is more resistant to permeation than ordinary concrete, has higher chemical stability, is highly resistant to sulphate erosion, reduces “concrete cancer†and reduces cracks caused by alkali-silicic acid reactions.
In addition to GGBS, the company also produces raw materials for glass manufacturing, abrasives and polymers. Civil and Marine belongs to Hanson and is a member of the Heidelberg Cement Group.