The offered composting technology is suitable for composting sewage sludge. It is based on the application of controlled composting for rapid degradation of organic pollutants and immobilization of inorganic micro-pollutants for safe land disposal by using industrial slurry-phase byproducts (e.g. by-products from sunflower seed oil processing industry). The process of controlled composting contributes to preserve the fertilizer value. The offered technology is able to utilize solid phase biogas residuals, post maturation of pre-maturated municipal sewage sludge from closed composting reactor or root-zone treatment. The end-product is a potential source for soil improvement and conditioning after 4-pre- and 6-week-term post maturation stages. The whole composting process is not longer than 70-90 days.