About Bureau of Indian Standards (BIS) (comments purpose only)

The Bureau of Indian Standards (BIS) is the national standards body of India, established under the BIS Act to promote safe, reliable, and sustainable practices across industries. It develops and publishes Indian Standards that help ensure quality, safety, and efficiency in products, processes, and systems.

In the context of biomass energy, BIS plays a vital role by creating standardized guidelines for biomass pellet plants, ensuring uniform quality, operational safety, and environmental compliance. This draft standard (Doc. No. FAD 20 – 27725) provides guidance for manufacturers, project developers, and industries engaged in producing non-torrefied and torrefied biomass pellets from agricultural residues.

Description

This document provides detailed guidelines for the design, operation, and optimization of biomass pellet plants. It covers the complete process flow for both non-torrefied and torrefied pellets, including plant layout, required machinery, safety measures, and operational best practices. The objective is to support industries, power plants, and entrepreneurs in producing high-quality pellets that reduce coal usage, minimize air pollution, and generate sustainable energy.

Key Point Summary

Promotes replacement of coal with agro-residue-based biomass pellets.
Defines process steps for non-torrefied and torrefied pellets.
Specifies required machinery (bale opener, shredder, dryer, hammer mill, pelletizer, torrefier, dust collectors, etc.).
Provides plant layout guidelines for safe and efficient operation.
Includes operational safety measures for workers and equipment.
Supports SAMARTH mission by the Government of India to utilize agro residues in thermal power plants.

Scope

Covers guidelines for operations, machinery, and plant layout for manufacturing non-woody biomass pellets (non-torrefied & torrefied).
Note: Municipal Solid Waste (MSW) pellets are excluded.

Terminology

Agro Residues: Non-woody crop waste like rice straw, wheat straw, maize stalk, etc.
Pelletization: Densification of biomass into uniform solid pellets.
Torrefaction: Heating biomass at 200–400°C in absence of oxygen to increase energy density.
Non-torrefied Pellets: Produced without torrefaction.
Torrefied Pellets: Produced after torrefaction, with better stability and calorific value.

Process Production (Non-Torrefied Pellets)

Raw Material Preparation: Grinding to <3.15 mm.
Moisture Equilibration: Adjusting to 10–14% moisture.
Pelletization: Compression in pelletizer under high pressure.
Cooling: Stabilizing pellets.
Packaging & Storage.

Machinery Used in Production (Non-Torrefied Pellets)

Process for Production of Torrefied Pellet

Biomass Preparation – shredding/chipping.
Drying – moisture reduction.
Torrefaction – 200°C–400°C for 20–60 min in low oxygen.
Pelletizing – high-pressure compaction.
Cooling – stabilizing.
Storage & Packaging – for industrial use.
Gas Management – flare or reuse torrefaction gases.

Machinery for Production of Torrefied Pellet

Same as non-torrefied pellet production, plus a Torrefier (reactor).

Plant Layout

Consider type & quantity of pellets, available space, safety, raw material supply, and expansion possibilities.
Layout must ensure safe workflow, minimum material handling, fire protection, dust control, emergency exits, ventilation, and future scalability.
Control Room should be isolated for safety.
Electrical systems must include ELCBs, MCCs, lightning arrestors.
Receiving & dispatch areas to be segregated for smooth transport.
Adequate green areas for environmental balance.

Operation Guidelines

Safety glasses, gloves, face shields mandatory.
Ear protection against high noise.
Dust masks (IS 9473 compliant) for workers.
Machines must be inspected before use.
Use push sticks/tools for small materials.

Conclusion

Biomass and torrefied pellet production offers a sustainable alternative to fossil fuels, reducing coal dependency, minimizing air pollution, and supporting rural farmers. By following these guidelines on process flow, machinery, plant design, and operations, manufacturers can ensure high-quality pellet output, optimized efficiency, and safe working environments.

PDF Download

Samarth Committee PDF Download Link

👉 Contact Servoday Plants & Equipments Ltd for the technical consultancy on pellet plant design and machinery.

Disclaimer

This draft guideline is prepared for reference and comments purposes only and is not to be treated as a certified Indian Standard until officially published by the Bureau of Indian Standards (BIS).