Closed-loop reuse

Electrolux, in Stockholm, Sweden, is reportedly using 40 to 80% commingled recycled plastics from sources such as used telephones, car parts, and other appliances, in the manufacture of vacuum cleaner housings. The company is also moving toward closed-loop reuse of in-plant scrap in future product designs,... 

Fossil Fuel-Fired Plants. In modem, fossil fuel-fired power plants, the Rankine cycle typically operates as a closed loop. In describing the steam—water cycle of a modem Rankine cycle plant, it is easiest to start with the condensate system (see Fig. 1). Condensate is the water that remains after the steam employed by the plant s steam turbines exhausts into the plant s condenser, where it is collected for reuse in the cycle. Many modem power plants employ a series of heat exchangers to boost efficiency. As a first step, the condensate is heated in a series of heat exchangers, usually sheU-and-tube heat exchangers, by steam extracted from strategic locations on the plant s steam turbines (see HeaT-EXCHANGETECHNOLOGy). 

Recycling and Reuse. (/) Install closed-loop systems. 2) Recycle on site for reuse. 3) Recycle off site for reuse. (4) Exchange wastes. 

Closed-Loop Recycling reclaiming or reusing wastewater for non-potable... 

This cooling water is usually arranged in a closed loop with the water being pumped through secondary coolers or over cooling towers and then returned to the jackets for reuse. Water quality must be good, with steam condensate being preferred, properly treated to prevent corrosion, etc. 

The Vinyloop process is based on the selective dissolution of PVC used in composites applications like cable insulation, flooring, tarpaulins, blisters, etc. After removal of insoluble parts like metals, rubber or other polymers, the PVC is reprecipitated with all additives by introduction of a non-solvent component whieh will form with the seleetive solvent an azeotropie mixture. By using typical conditions, the process is able to reeover a pure PVC eompound powder ready for use without any additional treatment like melt filtration or a new pelletisation (speeific characteristics of the powder are average diameter of 400 microns and bulk density above 600 kg/ eub.m). All the solvents used are eompletely reeyeled and reused. PVC compounds recovered in the Vinyloop process can be reused in a closed-loop recycling scheme... 

A pan-European initiative that aims to develop a sustainable closed-loop system for recycling and reuse... 

In the aforementioned closed loop water system the polluted process water is purified completely in one wastewater treatment scenario. Only one type of process water is produced for reuse. In practise several types of process water are needed, and also several types of polluted wastewater streams are produced. This is schematically shown in Figure 2. In that case it can be advantageous in technical, economic and environmental respects to include several closed loop water systems within one production line. 

In all closed loop water systems final residues such as sludges and concentrates are produced. These residual streams need further treatment. An appropriate selection of treatment steps, sequence of treatment steps, and process conditions to apply in each treatment step can result in recovery of valuable products for reuse. However additional and sometimes modified process steps may also result in an increase of treatment costs. These extra treatment costs have to be weighed against the benefits of the valuable products. 

Throughout the process, water, surfactant, and NAPL are recovered (as much as possible) for reuse and/or recycling. Many of the aboveground leaching facilities are essentially closed-loop systems. In most cases, the resulting clean soil can be used for backfill, landscaping, or similar purposes. 

This practice is undesirable because the addition of makeup water often results in the discharge of phossy water, unless an auxiliary tank collects phossy water overflows from the storage tanks, thus ensuring zero discharge. A closed-loop system is then possible if the phossy water from the auxiliary tank is reused as makeup for the main phosphorus tank. 

CO2 can be contained and recovered in the closed loops of gasifiers for remediation/reuse. 

Installation of closed-loop systems for in-process recycle Recycling on-site at other process units or off-site for reuse Finding new uses for previously unwanted byproducts Segregation of wastes by type to allow for recovery Reclamation processing of waste for resource recovery... 

Recovery, recycling and reuse Install closed-loop systems Recycle on site for reuse Properly segregate waste... 

The main technical difficulties of recycling are the variability of composition and the level of contamination. For this reason, it is advantageous to plan ahead a close loop material flow through the production, service life time, recycle steps. Applying the blends technology, it is possible to upgrade the recyclate performance, reusing the material for the same product. 

Reuse and Manufacturer/ Recycle more 10-Start closed loop recycling -0,9 -1,8... 

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