Compressed biogas,engineered fromfeedstock to cascade.

Rudra Technologies & Engineering Consultancy (RTEC) takes CBG plants from feasibility and DPR through process design, upgrading selection, detailed engineering and commissioning.

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Feasibility & DPRProcess designUpgrading selectionDetailed engineeringCommissioning

Conceptual CBG plant · feedstock to grid

Engineering knowledge.Practical solutions.Sustainable results.

RTEC is an independent engineering consultancy for compressed biogas and biogas projects. We do not sell equipment, so every recommendation is made on your feedstock, site and offtake.

One multidisciplinary team covers process, mechanical, piping, electrical and instrumentation engineering, from the first feedstock survey to performance testing.

18CBG and biogas projects engineered

95TPDCBG capacity engineered or reviewed

2,400TPDFeedstock handled across our designs

7States with RTEC-engineered projects

Who we work with

CBG developersGreenfield plants from site selection to COD.
Sugar mills & distilleriesPress mud and spent wash turned into a second product line.
Oil marketing company partnersPlants engineered to supply CBG under offtake agreements.
Municipal bodiesSegregated organic waste to CBG and compost.
Agri-business & FPOsCrop residue and dung aggregated into bankable projects.
Investors & lendersTechnical due diligence before capital is committed.

From waste to fuel, and back to the soil.

Every CBG plant is the same five-step conversion. The engineering is in getting each step right for your feedstock.

Total solids22%

Volatile solids80% TS

C : N25 : 1

Supply330 d/yr

Feedstock

Waste in.

Press mud, paddy straw, dung and municipal organics. We size the plant to the tonnage you can secure every month of the year, not the nameplate.

Anaerobic digestion

Raw biogas.

Controlled temperature, loading and retention time turn volatile solids into biogas at about 55% methane, carrying CO₂ and H₂S that must come out.

Purification & upgrading

Methane at 96% or more.

Desulphurisation, then VPSA, membrane or water-scrubbing upgrading, selected on gas flow and running cost, to meet IS 16087.

Compression

CBG at 250 bar.

Compressed into cascades for OMC retail outlets or injected into the city gas grid, with metering and odorisation engineered in.

By-product

Back to the soil.

Digestate is separated and enriched into fermented organic manure: a second revenue line when it is designed in from day one.

Ten services, one line of responsibility.

Engage us for a single study or for the whole project. The same engineers carry the design from the DPR to the performance test.

Assess

Feasibility & DPRTechno-commercial studies and detailed project reports lenders can assess.
Feedstock assessmentAvailability, seasonality, sampling and lab-tested biogas potential.
SATAT & scheme documentationTechnical submissions for SATAT, CFA and state incentive schemes.

Design

Process designDigester sizing, mass and energy balance, PFDs and P&IDs.
Upgrading technology selectionVPSA, membrane or water scrubbing, compared on your gas and tariff.
Basic & detailed engineeringMechanical, piping, electrical and instrumentation packages.

Deliver

Vendor & technical bid evaluationSpecifications, clarifications and comparative bid statements.
Project management & owner's engineerSchedule, interfaces and site quality on the owner's side of the table.

Optimise

Commissioning & performanceStart-up, guarantee tests and optimisation of running plants.
FOM & by-product valorisationSolid-liquid separation, enrichment and FOM market routes.

Eight feedstocks. Eight different plants.

Yield, digestion time and pre-treatment change with what goes in. We design around the feedstock, then the equipment.

Press mud

Sugar-mill filter cake. Seasonal supply means storage losses decide the design.

32kg / t

Paddy straw

High yield after shredding and pre-treatment; silica and lignin set the limits.

105kg / t

Cattle dung

Stable and forgiving; collection logistics matter more than the digester.

15kg / t

Municipal organic waste

Segregation quality drives pre-sorting, grit removal and reject handling.

30kg / t

Food & vegetable market waste

Fast-degrading and acidic; loading rate and buffering need care.

38kg / t

Distillery spent wash

High-strength liquid effluent suited to high-rate anaerobic reactors.

14kg / m³

Poultry litter

Good yield with ammonia and grit to manage through blending.

45kg / t

Napier grass

Dedicated energy crop for year-round supply alongside seasonal residues.

30kg / t

Indicative CBG yield per tonne as received. Actual yield depends on solids content, storage and blend, so we test before we size.

Plants we have engineered across India.

Client names are withheld under confidentiality. Capacities, feedstocks and our scope are as delivered.

Numbered pins match the project cards.

10TPD CBG

Press-mud CBG plant at a sugar mill

Client: Confidential sugar mill
Location: Kolhapur, Maharashtra
Feedstock: 300 TPD press mud
Technology: CSTR digesters, biological H₂S removal, VPSA
RTEC scope: DPR, process design, detailed engineering

15TPD CBG

Paddy-straw CBG plant

Client: Confidential CBG developer
Location: Bathinda, Punjab
Feedstock: 150 TPD paddy straw
Technology: Shredding and hydrolysis, CSTR, membrane upgrading
RTEC scope: Basic & detailed engineering, technical bid evaluation

5TPD CBG

Municipal organic waste to CBG

Client: Confidential municipal client
Location: Indore, Madhya Pradesh
Feedstock: 150 TPD segregated organic waste
Technology: Pre-sorting, pulping, CSTR, water scrubbing
RTEC scope: Owner's engineer, commissioning support

12TPD CBG

Cattle-dung CBG cluster

Client: Confidential agri-business client
Location: Banaskantha, Gujarat
Feedstock: 800 TPD cattle dung, village collection
Technology: CSTR, VPSA, FOM enrichment
RTEC scope: Feasibility, process design, SATAT documentation

20TPD CBG

Agri-residue CBG project, due diligence

Client: Confidential infrastructure investor
Location: Shahjahanpur, Uttar Pradesh
Feedstock: 210 TPD mixed agri-residue
Technology: Reviewed: dry-fed CSTR, membrane upgrading
RTEC scope: DPR review, technical due diligence for lenders

8TPD CBG

Upgrading plant performance optimisation

Client: Confidential CBG developer
Location: Mandya, Karnataka
Feedstock: Press mud and cattle dung
Technology: VPSA with H₂S polishing
RTEC scope: Performance audit and optimisation

CH₄ purity raised from 92% to 96.5%

Selected for your gas, not from our catalogue.

We carry no vendor mandates. Upgrading technology is chosen on gas flow, CO₂ content, power tariff, water and heat available at site.

Upgrading	VPSA	Membrane	Water scrubbing	Amine scrubbing
CH₄ in product	96–98%	96–99%	96–98%	>99%
Methane recovery	96–98%	97–99.5%	97–98%	>99.5%
Power, kWh/Nm³ raw gas	0.20–0.25	0.20–0.30	0.20–0.30	0.10–0.15plus process heat
Utilities	None beyond power	None beyond power	Make-up water, blowdown	Steam or hot water
Typical fit	5–20 TPD, steady gas	Variable flows, modular growth	Larger plants with water on site	Where waste heat is free

Indicative ranges for comparison. Final selection follows a site-specific mass balance and life-cycle cost.

Digestion

CSTRPlug-flowDry batchTwo-stage

Pre-treatment

ShreddingPulpingHydrolysisGrit removal

Gas cleaning

Biological H₂SIron oxideActivated carbonChilling

Compression & FOM

250 bar cascadeGrid injectionScrew pressFOM enrichment

Independent engineering for plants that have to run every day.

Technology neutral
No vendor ties. Digester, upgrading and compression choices follow your feedstock and offtake.
Feedstock first
Designs start from a year-round supply plan: availability, storage losses and blend.
Bankable documents
DPRs and technical reports structured for lenders, OMC partners and scheme reviewers.
Multidisciplinary
Process, mechanical, piping, electrical and instrumentation engineering in one team.
Lifecycle continuity
The engineers who write the DPR are on site for the performance test.
Operable plants
Layouts and specifications that account for maintenance access, spares and operator skill.

Technical insights

All articles

12 Sep 20269 min read

VPSA, membrane or water scrubbing: choosing a CBG upgrading technology

Why the lowest capex option is rarely the lowest cost per kilogram of CBG.

28 Aug 20267 min read

Press mud as a CBG feedstock: seasonality, storage and yield

Planning for a 160-day crushing season in a 330-day plant.

6 Aug 20268 min read

Paddy straw pre-treatment: what actually limits digestion

Particle size, silica and lignin, and the pre-treatment that pays for itself.

15 Jul 20266 min read

Making FOM a revenue stream, not a disposal cost

Separation, enrichment and the buyers who pay for consistent quality.

Let's discuss your project.

Share your feedstock, location and target capacity. An engineer, not a sales team, replies within two working days.

Emailhello@rtec.in

Office

Hyderabad, Telangana, India