EME: high quality glass is not a product of chance

During its more than 75 years of activity, German company EME has grown continuously to become both a manufacturer and supplier of equipment – specializing in particular in batch houses.

EME Maschinenfabrik Clasen GmbH was established more than 75 years ago and has become a leading manufacturer and supplier of batch and cullet handling equipment for the glass industry. The reliability and efficiency of the German company’s systems and equipment are renowned in the container, flat and special glass sectors all over the world. The systems EME supplies are designed by the company – but with specific client needs always taken into account. After completion of each project, EME’s after-sales service team provides prompt assistance if required.
EME prides itself in the fact that its systems and services enable customers to produce top quality glass. EME comprehensive solutions include innovative equipment for all areas of raw material handling and treatment as far as the glass melt, complemented at the production end by modern cullet handling and preparation systems.
EME has been a member of the SORG Group since 1987.
Batch houses are the heart and soul of EME’s business. The company has built batch houses for containers, float glass and special glasses, with capacities from five to over 1500 t/d.
EME batch houses use state-of-the-art technology to meet the following modern-day requirements:
•    production of accurate, homogeneous batch, even with high throughputs;
•    fully automatic operation in order to reduce personnel costs;
•    monitoring and recording of all variables;
•    sustainability/reproducibility of processes;
•    high system reliability and uninterrupted material flow;
•    functional design and ease of operation;
•    easy access and low maintenance;
•    low material losses and low dusting;
•    low emission levels;
•     adaptable for future needs.
Turnkey batch plants form an important part of the EME equipment programme.
Each installation is designed after completion of extensive preparatory work carried out in close cooperation with the customer.
Good glass quality does not depend solely on the correct preparation and handling of the materials to be melted. Efficient operation of the batch charger is also important.
Modern batch chargers must fulfil many criteria. For instance, the prevention of dust formation during the charging process is absolutely vital. Nowadays, environmental factors also play an increasingly important role in this part of the glass production process, and the batch charger can have a positive influence on NOx emissions and the heat balance of a furnace. The charging and distribution method is also important as the requirement for a closed batch blanket or separate batch piles varies according to the furnace type.
In addition to the new EME-NEND (No Emissions, No Dust) charger, EME supplies standard tube, screw, pusher, vibratory and chute chargers, in stationary and oscillating versions. EME can also design specialty equipment, to meet all customer requirements.
During glass production, cullet is created on the processing machines. Experience has shown that it is important to treat the cullet in the factory itself and return it to the melting process. This not only largely reduces the risk of contamination by foreign objects, but also avoids unnecessary and, above all, costly transport and intermediate storage. A cullet recycling system should be installed on each melter, so that different glass types do not become mixed.
EME has developed systems for treating cullet from the hollow and float glass industries.
EME scraper conveyors for the container glass industry have been operated successfully for many years. Their success is based on an improved design of the scraper chain, control of cooling water intake and the possibility to treat and re-circulate the cooling water. Water and energy consumptions are reduced and wear is significantly decreased, without detriment to the cooling of the glass.
Glass crushing is a very important part of cullet treatment, and low-maintenance EME crushers are equipped with wear-resistant crushing surfaces to maximize operating life. The crushing surface materials minimize abrasion so that negative effects on the glass quality are avoided.
EME supplies various crushers for specific applications, including hammer crushers, hammer mills, single roller jaw crushers, cutting mills, double roller crushers, edge and sheet crushers.
An important part of the EME programme is the design, engineering and construction of equipment for special applications or to meet specific customer requirements.
For example, EME has developed a pulverization concept for container cullet, which increases the possibility of using foreign cullet in the container sector, without detriment to glass quality.
EME engineers have also made full use of their expertise in the development of special equipment for the recycling of glass wool, television tubes and laminated glass.
Further examples of special equipment from EME are sand moisture measurement with automatic correction; and minor constituent weighing systems.
The application of computer- based automatic control technology leads to rational, efficient and secure operation of the installation. The ability of the control system to achieve optimum throughput and maximum accuracy is the basis for high productivity.
EME controls use decentralized system architecture, so that operations of the complete installation are not halted if individual components should fail.
Process visualization enables the operator to continuously monitor the status of the installation, so that he can use the logically arranged manual controls to intervene whenever necessary.
An essential part of complex control, weighing and dosing equipment is a PLC. EME uses the latest generation PLC for all process control tasks and calculations.
All weighing and dosing tasks are carried out with the utmost precision, as the programmes react within 100 milliseconds.
Dosing speeds for raw materials are set in the recipes and the PLC uses these parameters to control the dosing equipment.
In the case of power controlled dosing systems, the dosing speed is adjusted automatically. Any deviations from the set points in the dosing results are detected and automatically corrected in the subsequent charge of the same recipe, and the operator receives a warning message. This significantly increases the dosing accuracy for the constituents.
Individual dosing computers are no longer required as weighing indicators can be integrated in the new high capacity PLCs. This decreases the number of interfaces and, therefore, reduces fault potential and programming costs.
It is also possible to integrate the batch house control system in the main factory management computer system.
If interconnected processes are controlled from different control systems, a bus system is used for communication and the exchange of data. The introduction of bus systems means that slow, inflexible and fault-prone I/O connections are now a thing of the past.
A simple bus connection between the programming interfaces of the CPUs may be sufficient but, depending on speed requirements and the amount of data to be transferred. More complex connections, up to and including quasi redundant factory networks with network processors may be necessary.
The bus system creates a connection between the PLC, SCADA systems and administration computers and therefore data can be exchanged at all levels.
A SCADA system, in the form of a high performance PC, is used for operator access and monitoring. The SCADA system includes comprehensive database functions, for recording all operator interactions, fault messages, recipes and charge protocols.
Furthermore, PCs can also be used as additional work stations.
EME sets the highest standards for operational security of its equipment. Therefore software updates and fault-finding assistance are readily available via a modem, ISDN, or Internet connection that the customer controls.