quality standards (product quality standards)

Quality standards in the recycling and bioenergy sectors are the published specifications a product must meet before it can be sold legally, accepted by an offtaker, or used in a regulated application. They are not aspirational benchmarks — non-conformance leads to load rejection at the buyer's gate and, for export consignments, to detention by customs.

For compressed biogas, the binding specification is IS 16087:2016 from BIS: methane minimum 90% v/v, CO₂ maximum 4%, H₂S below 20 mg/Nm³, moisture dew point below −10°C, oxygen below 0.5%. For digestate and fermented organic manure, the Fertilizer Control Order (FCO) 1985 Schedule VI specifies nitrogen, phosphorus, potassium, carbon-to-nitrogen ratio, heavy metals (cadmium, lead, chromium, arsenic) and pathogen counts (E. coli and Salmonella). For e-waste fractions, BIS and ISRI grading defines copper purity tiers (Birch/Cliff 99%+, Berry mixed 96-98%), aluminium grades, and printed-circuit-board separation by gold content. For tyre pyrolysis oil, ASTM D396 fuel-oil equivalence is used as a benchmark, with sulphur limits set by the buying industry — cement kilns tolerate 1.0-1.2%, marine bunker buyers demand 0.5%, and IS 1460 diesel-blend stocks require below 50 ppm.

Each standard exists to manage a specific downstream risk. IS 16087 protects engine and pipeline integrity; FCO protects soil and food chains; copper grades protect smelter furnaces from contamination losses; sulphur limits protect downstream NOₓ scrubbers and human health. The cost of conformance is real — final polishing in CBG can add 8-12% to upgrading capex, FCO compliance for digestate requires pasteurisation and lab testing at roughly ₹3,000-5,000 per batch — but operating without it eliminates access to formal markets, leaving only informal grey-market buyers at 30-50% lower realisations.