What is a Fired Equipment? Types of Fired Equipment for Oil and Gas Industries

Types of Fired Equipment represent the thermal heart of downstream oil and gas operations, facilitating high-temperature chemical reactions and phase changes through controlled combustion. These units, governed by rigorous standards like API 560 and ASME Section I, transform fuel energy into process heat with precision and scale.

Technical Classification and Types of Fired Equipment in Refineries

Fired equipment in the oil and gas sector are engineered to precise specifications, primarily categorized by their function and design standards (ASME, API). Understanding these classifications is crucial for maintenance and safety protocols. The primary goal is efficient heat transfer while managing critical variables like tube skin temperatures and heat flux distribution.

Industrial Furnaces and API 560 Process Heaters

These are arguably the most critical Types of Fired Equipment in a refinery. Governed strictly by API Standard 560 (Fired Heaters for General Refinery Services), these units facilitate processes like crude distillation, vacuum distillation, reforming, and cracking. They typically feature a radiant section for intense heat exposure and a convection section for efficiency recovery.

Utility Boilers for High-Pressure Steam Generation

Boilers are another common type, essential for generating high-pressure superheated steam used for turbine drives, process heating, and stripping. Design is dictated by the ASME Boiler and Pressure Vessel Code (BPVC), specifically Section I for power boilers. These systems require sophisticated Burner Management Systems (BMS) to ensure operational safety and reliability.

Thermal Oxidizers and Waste Heat Recovery Units

Thermal oxidizers are specialized Types of Fired Equipment used for environmental compliance. They destroy hazardous air pollutants (HAPs) and volatile organic compounds (VOCs) by exposing them to extremely high temperatures (760°C to 1200°C). Often, these units are paired with Waste Heat Recovery Units (WHRUs) to recover the substantial thermal energy generated.

Figure 1: Cross-section highlighting the radiant and convection sections of a process heater, critical design zones for all Types of Fired Equipment.

Industrial Kilns and Flare Systems

While less common in typical crude processing, kilns are used in specific petrochemical operations for material processing (e.g., catalyst regeneration). Flares are safety-critical combustion devices used to safely dispose of excess combustible gases during upset conditions or emergencies, adhering to API 521 guidelines for pressure-relieving and depressuring systems.

Direct vs. Indirect Types of Fired Equipment Engineering

The distinction between direct and indirect heating is fundamental to combustion engineering and dictates the design of various Types of Fired Equipment.

• Direct Fired Equipment: In these systems, the products of combustion (flue gases) come into direct contact with the material being heated or processed. Examples include some types of dryers and incinerators. The advantage is high thermal efficiency, but it requires careful material compatibility analysis.
• Indirect Fired Equipment: This is the dominant design in refinery process heating (API 560 heaters). A physical barrier—the tube wall—separates the combustion gases from the process fluid. This prevents contamination of the product stream and allows for precise control over heat flux distribution, mitigating risks of tube rupture and material degradation.

Selection Criteria for Different Types of Fired Equipment Based on Fuel

Selecting the appropriate fuel is a critical phase in Combustion Engineering. The fuel choice dictates the burner design, material selection for furnace linings, and the overall footprint of the unit. In 2026, refineries are increasingly evaluating fuel flexibility to manage cost volatility and emissions.

Gas-Fired Systems and Combustion Engineering

Gas-fired units are the standard for high-efficiency Process Furnaces. They typically utilize natural gas or refinery fuel gas. These systems allow for precise flame control and lower maintenance compared to liquid fuels. However, gas composition variability requires sophisticated controls to maintain a stable Heat Flux Distribution across the radiant tubes.

Liquid Fuel Systems and Heat Flux Distribution

Heavy Fuel Oil (HFO) and diesel are common in regions with limited gas infrastructure. These Types of Fired Equipment require atomizing steam to break the liquid into fine droplets for combustion. A major challenge with liquid fuels is preventing “hot spots” or uneven Heat Flux Distribution, which can lead to localized tube overheating and coking.

Solid Fuel Systems and Thermal Efficiency Optimization

Coal and petroleum coke (petcoke) are primarily used in large-scale utility boilers. These systems require complex handling and ash removal infrastructure. Thermal Efficiency Optimization in solid fuel units often involves advanced air preheating and sophisticated soot-blowing schedules to keep heat transfer surfaces clean from fly ash deposits.

Performance Comparison: Coal vs Gas vs Oil Types of Fired Equipment

The following technical comparison highlights the operational trade-offs between different fuel configurations used in modern industrial heating.

Environmental Regulations for Modern Types of Fired Equipment

Compliance with API 560 Standards now necessitates the integration of Low-NOx (LNB) or Ultra-Low NOx (ULNB) burners. As of 2026, regulatory bodies have tightened limits on particulate matter and sulfur oxides (SOx). This has led to the widespread adoption of Selective Catalytic Reduction (SCR) units downstream of the convection section to neutralize pollutants before they exit the stack.

Safety Protocols and Burner Management for Types of Fired Equipment

The Burner Management System (BMS) is the “brain” of any fired unit. Modern systems must comply with SIL (Safety Integrity Level) ratings per IEC 61508/61511. The BMS ensures that the “Explosive Triangle” is managed via rigorous purge cycles and flame monitoring.

Common Questions About Types of Fired Equipment