For the pulp and paper sector, environmental stewardship encompasses the entire forestry value chain, from growing trees responsibly and making efficient use of raw materials and resources through to the effective and efficient recovery of paper for recycling.
PAMSA represents the local industry in these environmental areas:
Everything on earth requires water to thrive which is why efficient and responsible use of water is essential. Water is an important resource for forestry, as well as pulp and paper operations.
Water use at plantation level
Just like an industry or human activity, forestry plantations have both positive and negative impacts on the environment. One of the negative impacts is that they generally do use more water than the grasslands they generally replace. However, on a national scale, the amount of water is relatively small. On average, South African forestry uses 3% of available water resources –this varies from place to place and during different times of the year. To put this into context, irrigated agriculture uses approximately 62% of South Africa’s available water resources (Source: Forestry South Africa).
Water use at mill level
Water use and efficiency is key metric for PAMSA’s member companies as water is a vital resource throughout the pulp and paper making process. This includes raw materials preparation (washing of wood chips), pulp cooking, washing and screening, and use in paper machines (pulp slurry dilution and fabric showers).
It is also used for process cooling, materials transport, equipment cleaning, general facilities operations, and to generate steam for use in processes and on-site power generation.
Mills are continually identifying opportunities to save water throughout the production process, ensuring extensive water reduction, re-use and recycling within these processes and improving the quality of the waste water (effluent) the mills discharge.
In some instances, water is reused up to ten times throughout the mill and requires different levels of treatment depending on its use.
For example, water used in steam systems (boiler feedwater) must be purified to minimise corrosion. Once steam is condensed, it is recaptured and reused in the steam system. By contrast, raw water can be used without any treatment for non-contact cooling systems and can be returned directly to the river as long as it is not too warm.
Water and waste water (effluent) is routinely tested using temperature controls, oxygen level controls and other metrics to comply with relevant environmental regulations.
A lot of steam is generated by the paper machines and cooling towers. The water vapour is emitted from the process, and is what can be seen from the mill chimney stacks. The steam re-enters the atmosphere and ultimately will end up as precipitation in the local ecosystem.
DID YOU KNOW? When timber is harvested, 50% comprises water – this water is used in the manufacturing process. In fact, pulp contains 99% water and additives and 1% fibre. Once it has gone through the forming and press sections of a paper machine, it is 5% water and 95% fibre.
Member and industry case studies
Cleaner papermaking with renewable energy
The South African pulp and paper sector has been measuring its environmental performance for several years and continuously makes improvements to drive efficiency and cleaner production.
From an energy perspective, the paper and pulp industry uses both fossil fuels (petrol, diesel, oil and coal) and biomass-based fuels like black liquor and tree residues. “Black liquor” is a by-product from digesting pulpwood chips in the chemical pulping process.
For many years, efforts have been focused on efficient, renewable and sustainable energy utilisation. Many mills generate their own energy through co-generation (steam and electricity) using biomass and coal as fuel. Co-generation is a more efficient use of fuel as the heat from the generation of electricity is used to produce steam. Biomass is regarded as a renewable and carbon-neutral fuel and has a lower carbon footprint than coal and a number of mills generate more than half of their energy needs from biomass fuel.
Since there is very little water loss attributable to electricity generated via co-generation, this further implies that this method of power generation is a suitable option, within the scarce water context of South Africa. It is important to note, however, that although the pulp and papermaking industry does generate a significant portion of its own electricity, it presently remains reliant on the national grid for the balance of its power needs.