Chemical analysis – biomass to product

Wood and pulp

Our analyses cover fibre content, residual alkali, sulphur compounds such as sulphide, sulphite, sulphate and thiosulphate, total sulphur, oxalate, chloride, metals, and carbohydrates in both polymeric and monomeric form. We also analyse lignin and its molecular weight distribution, levels of tall oil and terpenes, hydroxy and volatile acids, as well as total solids and ash content.

Metal analysis

Metal analyses include, among others, calcium, copper, iron, magnesium, manganese, potassium, sodium, cadmium and lead. For broader and more sensitive multi‑element analyses, ICP‑OES is used, enabling simultaneous quantification of multiple elements in process liquids, solid samples, extracts and ash. Common target elements include aluminium, barium, cobalt, chromium, phosphorus, silicon and zinc.

Gas analysis

Gas analyses include, among others, hydrogen sulphide (H₂S), carbon dioxide (CO₂), sulphur dioxide (SO₂), as well as other volatile inorganic and organic compounds. These analyses support emissions monitoring, process control and compliance with environmental requirements.

Inorganic compounds

Inorganic compounds are analysed using high‑sensitivity instruments to identify salts, metals, oxides and anions, even at very low concentrations. We offer both qualitative analyses for identification and quantitative analyses for concentration determination. Techniques such as GC‑MS, HPLC, ICP‑MS and FTIR enable detection down to ppm and ppb levels, which is essential for trace analysis and control of residual substances.

Process liquids

Process liquids in the cellulose industry are analysed with respect to factors that affect process stability and final product quality. This includes anion concentrations and cation demand, carboxyl and uronic acids, total ASA content, carbohydrates, lignin and optical brighteners. Backwater is analysed for the same parameters, as well as starch.

Black liquor

Black liquor from the kraft pulping process contains both organic and inorganic components that need to be analysed to optimise chemical recovery, energy yield and process balance. Key parameters include fibre content, residual alkali, sulphur compounds, total sulphur, oxalate, chlorides, metals, carbohydrates, lignin including molecular weight distribution, tall oil, terpenes, hydroxy and volatile acids, as well as total solids and ash content.

White liquor and green liquor

White and green liquors are analysed to ensure a stable and efficient chemical balance in the recovery system. Important parameters include alkali content (total, active and effective), carbonates, sulphur components such as sulphide, sulphite, sulphate and thiosulphate, total sulphur, potassium and sodium, chlorides and metal concentrations.

Lime

Lime is analysed for free lime content, acid‑soluble sodium and metal concentrations. Common analysis parameters include sodium, magnesium, calcium, manganese, iron, aluminium, silicon, phosphorus and sulphur.

Tall oil

Tall oil is assessed based on acid value, content of neutral substances, fatty acids and resin acids, water and ash content, as well as total sulphur and sodium content. Soap is analysed with respect to theoretical tall oil yield, alkali content, calcium content, dry solids and calorific value.

Methanol

Methanol and contaminated condensate are analysed for methanol, water, ammonium, total nitrogen, TRS components such as hydrogen sulphide, methyl mercaptan, dimethyl sulphide and dimethyl disulphide, as well as total sulphur. Terpenoids, including α‑pinene, β‑pinene, 3‑carene and limonene, as well as mono‑, sesqui‑ and diterpenoids, are also analysed.

GC‑MS screening is used to identify volatile compounds that affect odour, product quality and environmental impact.

Organic substances

Organic acids

Organic acids and related compounds are analysed to assess the degree of degradation and overall process quality. Common analytes include levulinic acid, ethanol, glycerol, lactic acid, formic acid and acetic acid. The furan derivatives HMF and furfural are used as indicators of carbohydrate degradation and can also be quantified in black liquor to evaluate cooking conditions.

Organic compounds

Organic compounds and extractives are analysed in forest raw materials, process liquids and by‑products. The analyses include, among others, lignans, fatty acids and resin acids, sterols, steryl esters, triglycerides, as well as process chemicals such as anthraquinone. Rosin is analysed with respect to its impact on sizing performance and odour. Other carbon‑ and sulphur‑containing compounds, such as methanols, aldehydes, thiophenes and disulphides, are also analysed, as they are important for both process control and environmental assessment.

Textile

Viscosity measurements are used to assess molecular weight and degree of degradation in cellulose‑based textiles, particularly in recycling applications. Fibre analysis using light microscopy provides information on fibre type and fibre dimensions, while scanning electron microscopy (SEM) is used to study morphology and identify potential defects.

Metal concentrations are determined using ICP‑OES or ICP‑MS. Common analysis parameters include copper, zinc, chromium, lead, nickel, cadmium, iron, aluminium, sodium and potassium. Metal analyses are important for assessing environmental and health aspects as well as the material’s suitability for recycling.