Compression Force

SITA Deutschland GmbH is one of the largest German providers of waste and recycling services, with more than 100 facilities and more than 3,000 employees across Germany. SITA Environmental Solutions is a joint venture company owned by Suez Environnement (60 percent) and Sembcorp Industries (40 percent).

The Hochheim, Germany-based unit of France's Suez Environnement has recently been making use of the VK 12018 R fully automatic channel baling press from HSM Pressen Verwaltungs GmbH, Frickingen, Germany, to bale secondary commodities.

The new machine, "with its pressing power of 1,200 kilonewtons (122 ton force) as well as a frequency-regulated drive and conveyor belt technology," has helped the SITA plant be more productive and more energy efficient, according to the company.
 

Multiple Jobs
Mixed paper and cardboard, as well as a small amount of foil, up to a maximum material size of DIN (Deutsches Institut für Normung) A0 (841 millimeters by 1,189 millimeters, or 3 feet by 4 feet), can be compressed using the new baler.

Mountains of paper and cardboard pile up at the SITA Hochheim plant, as dozens of trucks arrive and unload their secondary commodity cargos every day.

Every year, this amounts to nearly 30,000 metric tons of paper, cardboard and cardboard boxes from households, printers, businesses and wholesalers with unsold newspapers that arrive at the facility for processing.

Joachim Häffner is the operations manager at the SITA Rohstoffwirtschaft (feedstock industry) business unit, responsible for operations at eight SITA plants in several cities, including Hochheim. SITA's Rohstoffwirtschaft unit also is responsible for the professional preparation and marketing of recycled paper as a secondary raw material.

This means the eight SITA sites sell approximately 550,000 metric tons of paper, cardboard and cardboard boxes every year to consumers.

At the SITA plant, the baler is fed using a wheel loader as well as with a new subsurface charging and loading conveyor.

In practical use at SITA, the HSM VK 12018 R achieves a throughput capacity of 35 metric tons per hour when loaded with mixed paper, meaning a finished bale is ejected every 100 seconds. In a single-shift operation, up to 300 metric tons of mixed paper are processed this way. This occurs at a total drive power of only 2 by 55 kilowatts.

The noise level produced by the system remains less than 80 decibels (adjusted), despite the baler's productivity, according to SITA.

Depending on whether they are comprised of paper, cardboard or boxes, the bales can reach a weight of up to 1,000 kilograms, or 1 ton, producing a bale measuring 1,100 millimeters wide by 1,100 millimeters high by 1,200 millimeters long (43 inches by 43 inches by 47 inches), which can be sold easily, according to SITA. A bale that can be compressed this compactly means less wire is used, and handling is reduced, according to HSM.

The VK 12018 itself measures 6.20 meters (244 inches) high and weighs 40 metric tons. Thanks to the compression force and the large bale format, fewer bales can be made from the same amount of material compared with the company's previous baler. SITA says it can, therefore, use the warehouse in the best way possible, speed up its logistics processes and reduce energy consumption at the same time.
 

Ready for More
In comparison with the SITA Deutschland facilities in Karlsruhe, Trossingen and Fulda, the site in Hochheim is rather small, but the tracks are set for growth, according to the company. In the coming years, SITA says it expects the quantities of paper and cardboard handled at the plant to increase considerably.

Given that the warehouse in Hochheim has limited space, the company was interested in ensuring the available space was optimized or best used. "We have to stack the paper bales in tall and stable stacks," Häffner says. An HSM baling press with a compression force of 1,200 kilonewtons (122 ton force) was considered ideal for the job.

"The tighter the bales are pressed, the more stable [they are] and, therefore, the higher we can stack them," Häffner says, "even in the open." High pressure makes the bales as strong as concrete blocks and even sustained rain cannot harm them, he says.

The highly condensed bales meet the needs of customers, such as producers of tissue paper. "We are the prime supplier for paper mills," Häffner says.

SITA also puts pressure on operational speed. The work done by three presses in the past will now be done by two.

SITA obtained quotes from seven suppliers, but the winner was the fully automatic channel baling press by HSM. Among the deciding factors were the baler's technology, such as the frequency-controlled drive developed by HSM. It reduces the power consumption of the channel bale press by up to 40 percent when compared with traditional drive systems, according to HSM.

"Sustainability is important to us," says Häffner. SITA, he says, regularly submits to an eco audit.

Along with the energy savings, the frequency-controlled drive can provide other benefits, such as potential process optimization by adjusting the speed to the production process and other external factors. The gentle operation of the motor is designed to reduce the number of starts and stops and avoids any unnecessarily harsh loading of the machine components, HSM says.

The baler has been in operation at SITA Hochheim since mid-June 2011, and Häffner says he has been pleased with what he has experienced in that time. "HSM's fully automatic channel baling press allows us to optimize our warehouses and logistics processes whilst simultaneously saving energy," Häffner says.

This story was submitted by HSM (www.hsm.eu) of Frickingen, Germany. It originally ran in the Nov./Dec. 2011 issue of Recycling Today Global Edition, sister publication to Recycling Today.