To better valorise the co-products : TURPENTINE AND TALL-OIL
Diagnostics of installations and mapping of emissions from mills
- Analysis of volatile terpenes constituting of turpentine and of wood extractives of tall-oil
- Potential of wood raw materials and wood residues in co-products to valorise
- Audit on mill site with tools and methodologies dedicated to sampling and analysis of gaseous emissions and vapors rejects
- Quality criteria, capacity/efficiency of co-products recovering
Generate Value...
With the development of green chemistry and with the demand in biosourced products, the pulp mills have interest in optimising the recovering / valorisation of their co-products to reduce the impact of their rejects.
Wood, in particular softwood, is rich in volatile terpenes and resin compounds. Most of he terpenes used in the flavour and perfume industries are derived from turpentine, especially those from kraft black liquors of pulp and paper mills. The other wood extractives, such as resins (resin acids, sterols, steryl esters) and fats (fatty acids, fatty alcohols and triglycerides) are extracted from kraft liquors (i.e. tall-oil) and are used as chemical intermediates for different applications (adhesives, paintings, inks, emulsifiers, etc).
Between 5 and 10 kg of sulfated turpentine and 30 to 50 kg of tall-oil per ton of pulp are recovered from black liquors of kraft mills; this contributes to a significant complementary revenue of several thousands k€ per year for one site. The mechanical pulping processes, in particular TMP process, generate also rejects rich in terpenes contributing to VOC emissions of the site (0.6 – 4 kg of VOC/ton of TMP pulp).
Cooking and turpentine recovery in a kraft pulp mill production linet
Context and achievement
Since about 15 years, CTP has developed a well-known expertise in the extraction and analysis of resins, fats and polyphenols from diverse industrial sample (wood, pulps, liquors, effluents, etc). Since 2015, CTP has enriched its study area with the development of a methology to identify and quantify the volatile terpenes in gas and vapours, allowing diagnosing the whole valorisation chain of co-products of a mill.
Sampling of volatile terpenes at the out of a aerator/extractor of a TMP pulp mill
Content of services
- Extensive analysis of functional lay-outs of installations and identification of emission points to study
- Campaigns of measurements and sampling on site, and in particular continuous sampling of gas and vapours
- Evaluation of turpentine potential of wood chips according to the ASTM D889-13 method
- Chromatographic analysis of the main volatile terpenes according to the ASTM D6387-99 method and of other extractives such as resins, fats and polyphenols
- Qualitative evaluation of co-products to valorise with the dosage of mercaptans, total sulphur, water content, etc.
- Mapping of emissions, weight balance, evaluation of recovering yields
- Development/adaptation of a simulation tool for the recovery of co-products integrated in a pulp mill
Evaluation of potential in turpentine and tall-oil in wood chips used on the mill site
Deliverables
- Report of working meetings, of trials and analyses
- Qualitative and quantitative balances of flux
- Simulation model on PS2000