The following are the processes involved in the Paper & Pulp industry that require heat energy to generate steam and heating water where we can use concentrated solar power technologies for meeting demand of heat energy:
- Pulp making
- Pulp processing
- Water treatment, steam & power generation, and effluent treatment
Solutions – IPH – Pulp and paper industry:
This industry is one of the most energy intensive and highly polluting sectors and is therefore of particular interest in the context of both local and global environmental discussions. The major share of energy, which is needed in industrial production processes is below 250°C – a temperature level, which could be well supplied by solar thermal technologies.
The process whereby timber is converted into paper involves six steps. The first four convert the logs into a mass of cellulose fibres with some residual lignin using a mixture of physical and chemical processes. This pulp is then bleached to remove the remaining lignin and finally spread out into smooth, pressed sheets (often with chemicals added to provide particular properties such as color or water resistance). The last step is Paper making which consists of preparation, forming, pressing and drying of the paper. The operations of pulp making, pulp processing and paper making require large amount of thermal energy in the form of hot water (60 °C) or low pressure steam (up to 150°C). This requirement of the thermal energy can be easily fulfilled by the solar thermal systems. Along with the manufacturing process, the plant requires lot of energy for utilities and waste treatment plants. The major energy requirement is for the water treatment and steam and power generation and effluent treatment. The following figure depicts the schematic of the paper and pulp manufacturing plant.