A mobile landfill gas flare is a complete flare package on a single skid with a hinged chimney that is raised on site by on-board hydraulic jacks. No telescopic crane is needed for the chimney, so the unit can be moved between wells or sites and be working quickly. This post explains how a 500 m³/h version was specified for a landfill in New Zealand, and when mobile makes sense.

The challenge: gas control before a permanent system exists

Landfill operators often need to burn gas before a permanent flare can be procured, installed and permitted. They may want a trial extraction, a temporary solution during site works, or time to prove gas yields before committing capital. A flare that arrives ready to run answers all three.

In this case a supplier’s agent in New Zealand was dealing with a landfill operator. The supplier had built a mobile unit for a UK trade exhibition and offered it for hire or sale. The suggestion to the agent was that the landfill might want to hire it before deciding to buy.

The approach: a hinged chimney and a self-contained skid

How the chimney goes up

The skid carries a chimney attached by a hinge. The skid is lifted by crane using four corner lifting eyes. On site, on-board hydraulic jacks raise the chimney into position. A fixed-chimney flare is delivered with the chimney separate and needs a suitably rated telescopic crane to stand it up. For a unit that moves, removing that step is the whole point.

The flare itself

• Flow: 500 m³/h, with a 5:1 turndown, so the lowest flow at which design conditions hold is about 100 m³/h. The same specification was offered at 1,000 m³/h.
• Temperature: at least 1,000°C when methane is above 25%, cooler as methane falls to 20%.
• Residence time: at least 0.5 seconds.
• Control: a PID controller driving a combustion air louvre, so the flare adjusts to changes in gas quality.

Everything upstream of the flame

The skid also holds the equipment that makes the flare usable on a live gas field:

• a galvanised condensate knockout pot with a polypropylene dewatering filter, so liquid cannot reach the booster;
• a 7.5 kW explosion-protected motor driving a stainless steel gas booster directly, delivering 500 m³/h at about 150 mbar;
• flame arresters on the booster inlet and outlet;
• a pilot gas line, UV flame detection and a PLC-controlled automatic ignition sequence;
• pressure gauges to monitor the filter and flame arrester, and a measurement point on the inlet line for a flow instrument.

Why it works: factory testing and fast set-up

Because the package is assembled and tested before it leaves the works, there is little to commission on site beyond connecting gas and power. That is a real advantage on a temporary job, where days on site cost money.

The ground-flare design also keeps the flame hidden inside the shroud. That helps with neighbours, and ground-level radiation is designed to stay within acceptable limits. The Environment Agency’s guidance on the management of landfill gas (LFTGN03) sets out how flaring fits into wider gas control at a site, whatever the flare’s size.

What to consider before choosing mobile

1. Hire first if the gas yield is unproven. A mobile unit lets you test extraction at real flows before buying a permanent flare.
2. Check the foundation. Even a mobile flare needs a level, firm base and room for the crane.
3. Plan the power supply. The booster motor needs a three-phase supply, or a generator.
4. Check the permit. Temporary flaring is still flaring. The regulator will want to see temperature, residence time and emission evidence.
5. Size for the gas you expect. A 5:1 turndown handles a good range, but a unit sized far above the gas yield will run at its lower limit and may trip on low methane.

FAQ

What is a mobile landfill gas flare?

It is a complete flare package, including booster, condensate pot and controls, mounted on a skid with a chimney that can be raised on site. It can be relocated between jobs.

Can a mobile flare meet the same temperature standards as a fixed one?

The design described here is a ground flare with automatic temperature control, holding at least 1,000°C at methane levels above 25%. Mobility affects how it is installed, not how it burns.

Why use hydraulic jacks for the chimney?

They remove the need for a telescopic crane to lift the chimney into place, which makes set-up faster and cheaper on short jobs.

Can I hire a flare before I buy one?

Hire is a common route when gas yields are uncertain or the need is temporary. Ask the supplier what is available.

Need gas control on a short timescale?

Contact our team with your site details and expected gas flow, and we will advise whether a mobile unit suits your project.