PRONTA Engineering

Line 04 · Biogas & RNG

Biogas is not a waste stream. It is an energy resource.

Your plant is already producing it. The question is whether you are burning it in a flare, using it to cut your own bill, or selling it as RNG into the natural gas distribution grid.

Biogas piping with a valve and process markings in a plant

From waste to energy

1,200 Nm³/h of biogas
treated
720 Nm³/h of
RNG

Injected into the natural gas distribution grid.

The problem

Between the gas you have and the gas you can sell there is sulfur.

And moisture, and siloxanes, and volatile organic compounds, and halides. Those impurities are what corrode engines, foul upgrading membranes, and keep an upgrading unit from reaching pipeline specification. Almost no biogas project fails because of the biogas: it fails because of what came with it and nobody characterized in time.

The value chain

From the digester to the pipeline, or wherever it pays you to stop.

Not every plant needs to go all the way to RNG. Some gain more by staying on self-consumption. The chain is the same; where you exit it is set by your numbers.

01

Digestion

Optimizing anaerobic digestion and gas production.

02

Collection

Gathering and conveying the gas with no losses and no air infiltration.

03

Characterization

What the gas carries and at what concentration. Everything else depends on this.

04

Pretreatment

Dehumidification and desulfurization to protect what comes next.

05

Upgrading

CO₂ removal until the gas reaches RNG quality.

06

End use

Self-consumption, engine generation, or injection into the distribution grid.

What we do

Four fronts, and the same team on all of them.

From the study that tells you whether the project holds up, through commissioning and spare parts.

Characterization and feasibility

What your gas is made of, what impurities it carries, and what can be done with it. That is where you learn whether the project holds up and in what configuration, before you commit any investment.

CompositionH₂SSiloxanes Heating valueMethane number

Pretreatment and desulfurization

Dehumidification and hydrogen sulfide removal with activated carbon filters. We design, build, and supply the system, including the filter media and its replacement.

DehumidificationActivated carbon H₂S removalFilter media

Upgrading to RNG

Integration of the upgrading system —PSA and other technologies, through international partners— until the gas meets the specification the distribution grid requires.

PSAUpgrading Pipeline injectionGas quality specification

Engineering and integration

Conceptual, basic (FEED), and detailed engineering. Process, piping, mechanical, instrumentation, control, and power. P&IDs, specification sheets, bills of quantities, safety vents, and complete electrical documentation.

P&IDPipingInstrumentation Control and powerCommissioning

What the plant gains

Four reasons, and only one of them is environmental.

Lower energy cost

Your own gas displaces purchased power and purchased fuel. It is the reason that holds up fastest in front of a finance committee.

New revenue

RNG can be sold into the natural gas distribution grid. A low-value byproduct becomes billable energy.

Fewer emissions

Methane captured and put to use instead of vented or flared, with the effect that has on your footprint.

Verifiable sustainability

Environmental metrics that are measured, not declared. The kind you can defend before the regulator and before your board.

Biogas plant with storage tanks and digesters

What we supply

We do not design everything for someone else to build.

In biogas we build and supply part of the system, and integrate the rest with international technology partners. When engineering and supply sit in the same contract, responsibility for the result is not split three ways.

  • Activated carbon filters for H₂S removal, built in house, with their filter media and replacement.
  • Dehumidification and filtration skids sized for your flow rate and your load.
  • PSA upgrading systems integrated through international partners.
  • Commissioning, maintenance, and spare parts supply.
Three-dimensional model of the RNG plant designed by PRONTA
Three-dimensional model of the RNG plant, the basis for the detailed engineering.

A case

Biogas from a wastewater treatment plant turned into RNG for the natural gas grid.

Biogas & RNG · Public utility operator

The challenge

Turn the biogas from a wastewater treatment plant (WWTP) into RNG fit for the grid. The gas arrived with hydrogen sulfide, moisture, and contaminants that blocked upgrading and put the equipment at risk.

Our solution

Conceptual, basic (FEED), and detailed engineering to integrate the complete plant: process, piping, mechanical, instrumentation, control, and power. Design and supply of the dehumidification system. Design, fabrication, and supply of the activated carbon filters for H₂S removal, including the filter media. Integration of the PSA upgrading unit from an international technology partner. And commissioning, maintenance, and spare parts.

The impact

Thousands of homes in the Aburrá Valley now receive natural gas that used to be a waste stream. The operator expanded its residential supply without adding a new source.

1,200 Nm³/h

Biogas treated

720 Nm³/h

RNG produced

+150 ppm

H₂S removed from the biogas

70 l/h

Water pulled out by the dehumidification skid

Why pretreatment decided the project

The PSA upgrading system removes CO₂ effectively, but it does little against H₂S. Without pretreatment sized to strip out more than 150 ppm of hydrogen sulfide, that unit would never have met pipeline specification — and the whole project would have failed on the cheapest link in the chain.

What was documented

Piping engineering for gas, cooling water, compressed air, and drains. Selection and sizing of safety vents and supports. Specification sheets, bills of quantities, and P&IDs. Electrical and control documentation with wiring diagrams, single-line diagrams, control loops, cable trays, and grounding grids.

Contact

Let's start by finding out what your gas carries.

A characterization costs a fraction of what a badly sized upgrading unit costs. Tell us what you have today and we will tell you how far you can take it. If the project does not hold up with your numbers, we will tell you that too.

pronta@epronta.com

Medellín, Antioquia · Colombia

We reply within two business days.

Your information is handled in accordance with our personal data protection policy.