|Reducing solvents in a company that produces plastic coated textiles||
MANUFACTURE OF CHEMICALS AND CHEMICAL PRODUCTS # 31
The Norwegian textile company featured in this case study, produces plastic coated textiles by the meter to be use for clothing. The company has 155 employees, and a turnover of 172 million NOK.
During the production of plastic coated textiles, the fabric is impregnated and/or coated with polyvinyl chloride (PVC) and polyurethanes (PUR) in a plastic-coating process and in a drip-impregnation process. The waste gas from the drip impregnation, white spirit and dioctylpthalate, are released as air emissions. The emissions are taken to the after-burning unit from which CO2, SO2, H2O and small amounts of hydrocarbons are emitted. When the machines are cleaned a lot of solvents containing methylethylketone and white spirit are used.
After the pigment containers are cleaned, the remaining pigments and white spirit are collected in separate tanks where the pigments settle. White spirit can be reused many times. Some of the sediments are dried and the solvents are burned in the after burning facility, the rest are disposed of as a special waste.Washed clothing and other things that contain solvents are put into a drying room where the vapor goes into the afterburner furnace.
Other wastes include: material scraps, cardboard, paper, woodwork and other kinds of production waste. The wastes from the production are delivered to the municipal waste dump, and the special wastes are delivered to Renor AS, in Aurskog, Norway.
The company wanted to further educate its employees and implement cleaner production in the production processes.
Cleaner Production Principle:
Recovery, reuse and recycle; Material substitution; Process modification
Cleaner Production Application:
The following CP options were reviewed at the facility, and the stage of implementation and level of commercialization of any involved technology noted.
|Cardboard and paper can be delivered as 2 separate fractions or as one fiber fraction.|
|Woodwork is used by the employees as firewood.|
|Other kinds of combustible materials are delivered to the municipal waste dump.|
|Other kinds of waste from offices, storage and production units are dumped on the waste dump.|
Environmental and Economic Benefits:
|Recycling of washing thinner by distillation gives a reduction of consumption of MEK and toluene of about 13,000 liters per year.|
|Recycling of solvents by distillation result in 12,000-13,000 liters of less special waste.|
|A possible start of a catalytic oxidation of white spirit and DOP will give a yearly reduction of emission to the air of about 1700 kg white spirit and 3 kg DOP.|
|There are no particular changes in the production volume or the water and energy consumption.|
|Source sorting of waste from the production (cardboard, paper and woodwork), will reduce the waste streams with 30-50 tons per year. Source sorting of paper from the offices, will reduce the waste stream with 8-10 tons per year.|
|The waste to the municipal waste dump is reduced by about 30-50 tons per year. The special waste is reduced by about 60 % or 12,000 liters per year.|
Investment costs were:
|distillation installation, 40,000 NOK,|
|catalytic combustion installation, 300,000 NOK, and|
|barrel press, 16,500 NOK.|
Operational and maintenance cost figures include:
|reduced costs for special waste of about 120,000 NOK per year,|
|reduced waste costs by 20,000 NOK per year because the paper and cardboard are recycled, and|
|reduced waste costs because the barrels are compressed.|
The recycling of MEK and toluene had payback time of 0.8 years. The barrel press had a payback time of 1.6 years.
This case study was translated from Norwegian and submitted to UNEP IE on behalf of the Norwegian State Pollution Control Authority by Stiftelsen Ostfoldforskning in February 1994. It was reviewed and edited by UNEP IE in July 1995. It has subsequently undergone a formal technical review in September 1998 by Dr. Prasad Modak, Environmental Management Centre, Mumbai, India..