Recovery Furnace Sootblower Valve Control for Lower Steam Use
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Recovery furnaces in the pulp industry face challenges in reducing steam consumption for sootblowing without compromising soot removal efficiency, as existing methods either reduce efficiency or are technically complex and inefficient.
Innovation Solution
A method and arrangement that utilize a directionally controlled valve to enable sootblowing only during the insertion or retraction of the lance tube, with a control system to manage overlapping movements and steam flow, minimizing pressure peaks and dips, and incorporating a throttled bypass for cooling, along with electronic and optical sensing means for automation and optimization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the operational intervals of sootblowers are extended to reduce steam consumption, then steam consumption is reduced, but soot removal efficiency decreases
Solution Approach 1:
The patent applies periodic action by operating sootblowers in alternating sequences rather than continuously or simultaneously. Multiple sootblowers are activated in a coordinated periodic pattern where one sootblower operates while others are inactive, then they switch in sequence. This periodic operation reduces overall steam consumption while maintaining effective soot removal through the cumulative effect of multiple cleaning passes.
Solution Approach 2:
The patent implements dynamics by making the sootblowing system adaptive and flexible in its operation. The control system dynamically adjusts which sootblowers are active at any given time based on operational conditions, allowing optimization between steam consumption and cleaning effectiveness. This dynamic coordination enables the system to respond to varying soot accumulation patterns while managing steam usage efficiently.
2Productivity
If multiple sootblowers are operated simultaneously to increase soot removal efficiency, then soot removal efficiency is improved, but steam consumption increases
Solution Approach 1:
The patent uses periodic action to coordinate multiple sootblowers operating in alternating sequences. Instead of simultaneous operation, sootblowers are activated in a timed sequence where one completes its cycle before the next begins. This periodic pattern allows multiple sootblowers to contribute to soot removal over time without the cumulative steam consumption of simultaneous operation, achieving efficient cleaning with reduced steam usage.
3Loss of energy
If pressure reduction is applied at a single common location to save steam, then steam consumption is reduced, but sootblowers must operate one by one reducing system efficiency
Solution Approach 1:
The patent applies segmentation by dividing the steam distribution system into multiple independent zones, each with its own pressure control capability. Instead of a single common pressure reduction point, each sootblower or group of sootblowers has independent pressure control. This segmentation enables multiple sootblowers to operate simultaneously or in sequence without interfering with each other, maintaining system efficiency while achieving steam consumption reduction through coordinated pressure management.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly reduces steam consumption while maintaining or increasing soot removal efficiency, allowing for more frequent cleaning and improved heat exchange efficiency, thereby reducing downtime and increasing the overall availability of the recovery furnace.
Implementation Method 1
a steam feed tube connected to the lance tube for feeding sootblowing steam to be ejected through said at least one nozzle into the recovery furnace
Implementation Method 2
said steam tube having a valve for admitting steam through said at least one nozzle only when the carriage with the lance tube is moving
Implementation Method 3
a throttled bypass for cooling
Data Source
AI summary
This invention relates to a method of rebuilding a sootblowing system of a recovery furnace, said sootblowing system including a plurality of sootblowers (1), and each sootblower (1) including a frame (10), a moveable carriage (14) supported by the frame (10), a motor (2) for moving the carriage (14), a lance tube (11) mounted on the carriage (14) to be insertable into and retractable from the recovery furnace (8), said lance tube (11) having at least one nozzle (12), and a steam feed tube (45, 35, 15) connected to the lance tube (11) for feeding sootblowing steam to be ejected through said at least one nozzle (12) into the recovery furnace, said steam feed tube (45, 35, 15) having a first valve (3) arranged to admit steam through said at least one nozzle (12) only when the carriage with the lance tube (11) is in an activated position, i.e. during retraction and introduction of the lance tube (11), wherein further providing means (4, 30) to arrange for controlled steam supply merely during a limited time period, e.g. merely during introduction.