EBS-NQ Asphalt Mixing Plant Burner with Electronic Proportional Control

Product Introduction

The EBS-NQ is an asphalt mixing plant burner developed around electronic proportional control. Eight published models cover output capacities from 4,150 to 41,500 kW, with corresponding oil-consumption ratings from 370 to 3,710 kg/h.

The control system coordinates fuel delivery and combustion air across a stated 1:10 modulation range. This allows burner output to follow changes in plant firing demand rather than relying on a single fixed operating point.

A variable-frequency fan, compact integrated structure, movable base and protected control components support installation and operation in asphalt production environments. Final model selection must still be based on a project heat balance rather than the nominal mixing plant model alone.

Electronic Proportional Control

Coordinated Fuel and Air

The EBS-NQ uses electronic proportional control to manage fuel and combustion air. The two control paths are calculated and adjusted through the burner control logic so that the firing rate can respond to the plant’s thermal demand.

This control method is intended to support more repeatable adjustment than a basic mechanically linked system. Actual combustion performance depends on correct setup of the fuel curve, air curve, sensors, actuators, fan, dryer draft and exhaust system.

1:10 Modulation Range

The published adjustment ratio is 1:10. A wider operating range allows the burner to reduce output during lower production demand and increase firing as the required heat load rises.

The available field modulation range may be affected by:

• Fuel type and heating value

• Minimum stable fuel pressure

• Atomization conditions

• Combustion-air pressure

• Burner head configuration

• Dryer draft

• Required excess-air level

• Flame stability

• Site emission limits

A 1:10 burner range does not mean that every asphalt plant should operate continuously at the lowest possible firing rate. The burner and dryer must still maintain sufficient air and fuel velocity for stable mixing and combustion.

Load Response

When aggregate throughput, incoming moisture or target discharge temperature changes, the required heat input also changes. Electronic control allows the burner to adjust fuel and air together as the firing command moves between load points.

The plant control sequence should define how the burner responds to temperature feedback, production changes, alarm conditions and shutdown commands.

Combustion Air Control

Variable-Frequency Fan

The EBS-NQ uses frequency conversion to adjust fan operation according to combustion demand. At reduced firing rates, the fan does not need to run continuously at its maximum speed while airflow is restricted only by a damper.

The product page reports a 30–40% reduction in fan electrical consumption and an approximately 2% improvement in thermal utilization under its stated operating conditions. Actual results depend on the comparison baseline, operating hours, load profile, dryer resistance, fan selection, tuning and maintenance condition.

Project evaluation should therefore compare measured fan power and fuel consumption under similar production conditions rather than treating published percentages as guaranteed savings.

Dryer Draft and Exhaust System

The burner fan does not operate independently of the asphalt plant exhaust system. Combustion-zone pressure is influenced by the dryer, ductwork, baghouse, induced-draft fan, dampers and stack.

Incorrect draft may contribute to:

• Flame instability

• Excessive combustion air

• Incomplete combustion

• Unstable aggregate temperature

• Positive pressure near the burner opening

• Higher CO or particulate levels

• Heat loss through the exhaust

Burner commissioning should include draft measurements at the operating points used by the plant.

Integrated Burner Structure

Compact Modular Layout

Fuel lines, airflow components and control connections are arranged within an integrated burner assembly. This reduces the number of separately positioned components around the main burner body and provides a more organized installation layout.

The actual foundation, burner opening, support structure, service clearance and connection positions must be checked against the selected model drawings.

Movable Base

Product images show the EBS-NQ installed on a framed base with wheels. The movable arrangement can assist positioning and provide access during installation or scheduled maintenance.

The burner must be secured in its operating position. Wheels or a movable frame do not replace the required foundation, alignment, locking and structural support defined for the installation.

Service Access

The burner arrangement provides access to the fan housing, fuel components, combustion head and control enclosure. Maintenance planning should reserve enough space to inspect or remove these components without interfering with nearby plant structures.

Before installation, review:

• Burner withdrawal distance

• Combustion-head access

• Fan and motor service space

• Fuel-train access

• Control-panel door clearance

• Cable and pipe routes

• Lifting points

• Platform and guard requirements

Asphalt Plant Integration

Calculate the Required Heat Input

The burner should be selected from the actual drying and heating requirement. Nominal asphalt plant size alone does not establish the required burner capacity.

The heat calculation should include:

• Required aggregate throughput

• Average and maximum aggregate moisture

• Incoming aggregate temperature

• Required discharge temperature

• Recycled material percentage, where applicable

• Dryer heat loss

• Exhaust-gas temperature

• Fuel heating value

• Site altitude and ambient conditions

• Expected operating margin

Evaporating water from the aggregate is a major part of the dryer heat load. A plant processing wet aggregate may require substantially more heat than the same plant operating with dry material.

Match the Flame to the Dryer

Burner output is only one part of the selection. The flame must also be compatible with the combustion zone and dryer geometry.

Project review should consider:

• Dryer diameter and length

• Burner opening dimensions

• Combustion-zone length

• Flight arrangement

• Aggregate curtain location

• Burner insertion or nose length

• Counterflow or parallel-flow configuration

• Available negative pressure

• Baghouse temperature limits

An oversized burner may spend most of its operating time at a low percentage of rated capacity. This can reduce air and fuel velocity, narrow the useful control range and make combustion tuning more difficult.

Fixed and Mobile Plants

The compact burner structure can be evaluated for both fixed and relocatable asphalt plant projects. A mobile project still requires verification of transport dimensions, weight distribution, flexible connections, alignment procedures and reconnection checks after relocation.

Fuel Configuration

The published EBS-NQ model table provides oil-consumption values. These figures should be used as nominal model references rather than guaranteed site consumption.

Fuel demand varies with:

• Net heating value

• Fuel density and viscosity

• Aggregate moisture

• Plant production rate

• Required material temperature

• Combustion excess air

• Dryer and exhaust losses

• Burner tuning

• Operating time at partial load

For heavy-oil operation, the fuel preparation system may need heating, circulation, filtration and viscosity control. Atomizing-air or pressure requirements must match the selected burner and fuel system.

Alternative gas or combined-fuel projects require a project-specific fuel-train design, valve selection, pressure range, safety sequence and consumption calculation. Gas or dual-fuel capability should not be assumed from the oil-consumption table.

Safety and Protection

The product page lists IP55 protection for components and IP56–IP67 protection for the main control system. The exact rating applicable to each enclosure or assembly should be identified in the approved technical documents.

An IP rating describes protection against access, dust and water under defined test conditions. It does not describe combustion safety, explosion protection or suitability for every outdoor environment.

A complete burner safety system should coordinate:

• Combustion-air proving

• Pre-purge and post-purge

• Ignition sequence

• Flame detection

• Fuel-pressure monitoring

• Safety shut-off valves

• Low-fire start position

• Temperature limits

• Dryer draft interlocks

• Emergency shutdown

• Plant permissive signals

• Fault indication and reset logic

The burner must shut off fuel safely when the flame is lost or a required operating condition is not satisfied. Safety devices should remain effective independently of normal production control.

Local fuel-gas, fuel-oil, electrical, fire-protection and emission requirements must be addressed by the plant designer and commissioning team.

Commissioning

Commissioning should be performed by qualified combustion and electrical personnel with the asphalt plant placed in a controlled operating condition.

A typical process includes:

1. Verify burner mounting, alignment and combustion-head position.

2. Check electrical supply, phase sequence and grounding.

3. Inspect fuel lines, valves, filters and leak-tightness.

4. Confirm fan rotation and airflow proving.

5. Test the purge sequence and all permissive signals.

6. Verify ignition and flame-detection response.

7. Establish a stable low-fire operating point.

8. Set fuel and air values across the required firing range.

9. Measure dryer draft and exhaust conditions.

10. Test load transitions using controlled production changes.

11. Verify all alarm and shutdown functions.

12. Record the final settings and combustion measurements.

Combustion should be checked with suitable instruments. Relevant measurements may include oxygen, carbon monoxide, carbon dioxide, nitrogen oxides, exhaust temperature, fuel pressure, combustion-air pressure and dryer draft.

Settings should not be copied directly from another plant, even when both plants use the same EBS-NQ model.

Maintenance

A maintenance schedule should reflect the fuel quality, operating hours, dust exposure, ambient conditions and plant production cycle.

Routine Checks

Inspect the following items regularly:

• Fuel filters and strainers

• Fuel pressure and temperature

• Atomizing components

• Flexible fuel connections

• Flame detector

• Ignition components

• Fan inlet and impeller

• Air-pressure switches

• Actuators and linkages

• Electrical terminals

• Control-enclosure seals

• Combustion head

• Fasteners and mounting points

Heavy-oil systems may require more frequent cleaning because viscosity, contaminants and carbon deposits can affect atomization.

Combustion Review

Retuning may be required after:

• Changing fuel type or supplier

• Replacing a nozzle or fuel valve

• Repairing the fan or motor

• Modifying the dryer or baghouse

• Changing production rate significantly

• Moving the burner to another plant

• Observing higher fuel use, smoke or unstable temperature

• Receiving abnormal CO, NOx or oxygen readings

Repeatedly resetting burner faults without identifying their cause can expose the equipment and plant to further risk.

Engineering Documentation

For EBS-NQ model selection, provide:

• Asphalt plant manufacturer and model

• Dryer type, diameter and length

• Burner opening and available installation space

• Required aggregate throughput

• Average and maximum moisture content

• Incoming and discharge temperatures

• Fuel type and analysis

• Available fuel pressure

• Site altitude and ambient temperature

• Exhaust fan and baghouse information

• Local NOx, CO and particulate limits

• Electrical supply

• Existing control-system signals

• Retrofit or new-installation status

The engineering review should produce a defined burner model, fuel configuration, interface list, installation drawing and commissioning scope before the order is released.

Technical Parameters

Why Choose EBS-NQ?

• Fourth-generation electronic intelligent proportional control architecture

• 1:10 ultra-wide adjustment ratio for precision thermal modulation

• Digitally synchronized fuel–air control for stable and efficient combustion

• 30–40% reduction in fan power consumption with frequency-controlled airflow

• Industrial-grade IP55–IP67 protection for demanding on-site environments

• Designed for high-load, long-duration, precision-controlled asphalt production