Water-soluble polymers disposal options

Figure 12.2. Environmental disposal options for water-soluble polymers.

Disposal Options for Biodegradable Water-Soluble Polymers... 

Waste-management requirements and disposal options are the drivers for research to develop environmentally biodegradable polymers and to establish laboratory testing protocols. It is commercial opportunities that indicate polymer types, structures, properties and uses that dictate waste management and disposal requirements. Disposal methods and locations identify the testing protocols that must be established for polymers in order to evaluate their environmental degradation under laboratory simulated environmental exposure conditions. Major options for the disposal and waste-management of water-soluble polymers are indicated in Fig.2. 

Clearly, one option to reduce the add-on is to use high-efficiency size formulations. However, there is a limit to what can be achieved by this approach. Even if the add-on is reduced to only 5%, the pollution load is still substantial. The two main options to facilitate disposal are (a) recovery of size polymers and (b) biological effluent treatment. Recovery of size polymers, particularly from water-soluble synthetic sizes, is based on extraction washing using the minimum quantity of water. Recovery rates in the region of 50% have been quoted for polyfvinyl alcohol) and carboxymethylcellulose size formulations. It is necessary to apply one of three concentration techniques precipitation, condensation or ultrafiltration [205]. 

---