In tissue production, the energy use for drying is considerable. Modern tissue drying processes utilize direct fired, high temperature, drying hoods where the flue gases from LPG or natural gas combustion are blown towards the wet tissue paper.

The quality demands on tissue paper are high; visual imperfections or odors caused by particles originating from the flue gases are unacceptable.

Combustion of fossil gases used to generate the process heat is the main source of greenhouse gas emissions within the paper industry. Alternatives to the fossil gas has not been available due to the combination of demand on costs and quality over time. Tissue production is generally on 24/7 operations and cannot risk any production hick-ups due to variety in heat quality.

The tissue making process

The common tissue making process starts with dissolved pulp that is distributed (sprayed) onto a felt and formed into a sheet. Due to capillary forces the fibers sticks to the felt and gets transported to the first part of the drying where water is pressed out, the pulp is transferred to the Yankee cylinder and the felt returns to pick up new pulp. The Yankee cylinder is a big cylinder which is heated from the inside, most commonly by hot steam. The pulp is passing through the drying hoods, where hot air, generated from combustion of fossil gas, dries the tissue. Next step is the creping section where the tissue is scraped from the yankee cylinder and creped, i.e. generating the thickness and fluffy characteristic for tissue. Last step is the reel up of the jumbo rolls. In a tissue converting process the jumbo reels are then cut and packed (e.g. to napkins, toilet paper, household paper etc.) before being sent to the tissue consumers.

Changing to renewable gas for one tissue mill (80 000 MWh LPG)
– How much CO2-emissions are spared?

The trend is clear - gas is the future for tissue drying

Tissue producers and machine suppliers are united:

Combustion of gas is the tissue drying method for the foreseen future.

Other solutions, like electrical dryers cannot meet the requirements of high process temperatures and quality in combination with low cost.

In fact, several machine suppliers look into new solutions which increase in gas consumption. For instance, circulate heat generated in the drying hood into the yankee cylinder – eliminating the need of steam, or upgraded Through-Air-Drying solutions etc.

The need of renewable alternatives is therefore acute and increasing.

According to a recent market study conducted by consultancy firm BCNP, the total consumption of gas within the paper industry is today 84 000 GWh. That is a market value of about EUR 3 bn

Could renewable gas from Meva Energy replace fossil gases?

RISE (Research institutes of Sweden) performed extensive test campaigns in September 2017 in order to verify the suitability of renewable gas from Meva Energy in tissue drying. Gas from Meva Energy’s plant in Hortlax, Piteå were used for the trials.

The results were impressive:

  • Stable flame with 100% syngas
  • Even and complete combustion
  • Very low particle levels in exhaust gas
  • No odor or damage of tissue

The main conclusion from the reports:
Meva Energy’s renewable gas could replace fossil gases, such as LPG and NG in tissue drying

What could Meva Energy do for the tissue industry?

Improve environmental footprint

by replacing fossil gases (such as LNG and LPG) in industrial burners with renewable, locally produced, gas from Meva Energy plants at production sites

Reduce costs

by utilizing low cost biomass such as sawdust, waste wood, bark etc. locally sourced. The renewable nature also free emission allowances and carbon taxes. What will be the future price of fossil combustion including allowances and taxes?

Increase sales

by being able to offer fossil free solutions and products. How much could you increase the price or sales by releasing the market value?