Others Services
Steam System Solutions
The DUCOVA team is highly skilled in the art of energy savings. This section features various installations as well as innovative and tested means of increasing the efficiency of your steam system.
Here are a few steam system solutions:
The efficiency of a steam system requires the annual monitoring of steam traps. In this regard, DUCOVA can carry out your technical surveys.
Steam-Condensate Closed System
The concept of steam-condensate closed systems consists of returning the condensate and flash steam to a pressurized receiver tank. When we realise that the condensate contains between 18 to 23 per cent of the total heat of the entire steam system, it is very interesting to recover all that often difficult to manage and often hated energy. Moreover, you reduce the need to use anticorrosive chemical treatment products. This system also eliminates the need for most mechanical condensate pumps. When applicable, this is the most efficient means of recovering energy in a steam system, as well as generating significant and, in some cases, considerable savings.
Advantages:
- Energy Recovery: In light of current energy costs, it is the main advantage of the system;
- Eliminate condensate and steam flash loss, which represents 18 to 23 per cent of the heat of the entire steam system, and reduce the costs relative to water supply;
- Reduction in noncondensable gases, thus optimising heat exchanges and reducing the use of chemical products and corrosion;
- Reduction in anticorrosive chemical products due to less make-up water injected into the system, which allows for a reduction in blowdown. Piping erosion problems are also reduced by easier and more reliable control of the system;
- Reduction in part and maintenance costs thanks to the elimination of condensate pumps;
- Reduction in environmental impact due to lower consumption of chemical products and energy;
- Possible applications to new or existing systems for certain components only.
The following illustration demonstrates an open system.
DUCOVA IS HIGHLY SKILLED IN THE DESIGN AND APPLICATIONS OF CLOSED SYSTEMS
The following illustration demonstrates a closed system (SCCS). Note the absence of condensate pumps, condensate tanks and the elimination of flash loss.
Deaeration
Why deaerate steam systems?
Though essential, the elimination of noncondensable gases from steam systems is often neglected. De-aerating improves the energy efficiency of steam systems and reduces corrosion.
The presence of noncondensable gases in steam systems reduces the steam's partial pressure and, consequently, steam temperature, which renders energy transfer more difficult. This then necessitates an increase in evaporator pressure to maintain the same temperature. A higher consumption in combustibles is thereby required, which in turn increases costs. Moreover, the presence of noncondensable gases, such as CO2, increases corrosion, and thereby causes an overconsumption in anticorrosive products and frequent repair. Deaeration avoids all of these useless costs.
How do you deaerate?
To deaerate, we install thermostatic air vents comprised of a finned tube and a GESTRA steam trap equipped with an H-capsule. Upon starting up the system, the thermostatic air vent is opened and allows the air out and then closes once it has escaped. This vent also allows for constant deaeration. The finned tube creates a cooling point where condensation is enhanced, thus concentrating the noncondensable gases to be expelled by the thermostatic device. Once gases have been completely purged and pure steam is detected, the thermostatic steam trap closes.
Here is an example of how deaeration applies to steam vents:
This illustration demonstrates where thermostatic vents should be installed on a steam line. Fastened to each pipe turn and at the end of the lines, the vents ensure the maximum elimination of air at system start-up and eliminate noncondensable gases as soon as possible.
Do not hesitate to contact your DUCOVA Representative for more information.
Technical Surveying
DUCOVA carries out a technical survey to verify the state of steam traps, which includes:
- A localisation plan (personalised plan update on AutoCAD);
- A chart outlining the state of steam traps.
The survey report presented to you will include the following:
- Assessment of steam trap mechanism (using a vapophone VKP Ex);
- Identification of steam traps by tagging;
- Equipment installations;
- State of steam trap mechanism;
- Access to steam traps (notice of accessibility);
- Recovered condensate (yes or no);
- Identification of installed steam trap manufacturer;
- Identification of GESTRA equivalents;
- Identification of problems linked to system mechanism, outlined in a report.
The survey carried out by DUCOVA technicians has many advantages:
- Improved maintenance scheduling, thanks to the knowledge of the current state and quality of the system;
- Increased longevity by correcting weaknesses in the system;
- Increased system efficiency by replacing defective steam traps;
- Time savings relative to system maintenance;
- Savings thanks to recovered condensate after system improvement.
Biomass Combustion
Performance review of biomass fired thermal power plants
DUCOVA experts inform you of the exact state of your installations such as their current and potential output. The superior quality of the information gathered ensures efficient decision-making and proper management of your power station.
Always with the intention of making clear recommendations based in fact, the surveys carried out by our specialists rigorously gather the following data:
- Carry out a complete survey of your installations:
- Equipment description;
- Manufacturer identification and rated capacity;
- Working schematic of your installations on AutoCAD
- Evaluate, test and report on current equipment operating conditions and recommendations on required maintenance;
- Evaluate with precision the steam production and efficiency of your facility;
- Recommend and estimate costs for the purposes of improving facility efficiency: cost/benefit analysis.
Service agreements for combustion control systems
Always with combustion optimisation in mind, DUCOVA adapts service agreements to meet the specific needs of each installation.
The efficiency of your control system and its components is essential to the proper functioning and the feasibility of your facility. You must, therefore, be vigilant.
Always adapted to the particular requirements of each control system, the service agreement can include the following services:
- Installation of controller software updates upon manufacturer release;
- Behavioural analysis of installed programs;
- Instrument calibration, such as combustion gas analysers;
- Performance audit of mechanical systems, namely the air flow control, feeders, control valve, etc.;
- Analysis of proper response and data transfer for all instruments;
- Combustion adjustment and redefining set points to account for changes, if necessary;
- Report redaction outlining walk-through assessment and stating the feasibility of the current system’s operations;
- Remote monitoring and diagnostics via modem are available within the framework of a service agreement.
Thermal Power Plant Automation
Control strategy implementation for biomass combustion
DUCOVA has developed two control units, especially designed for the wood processing industry, to automate thermal power plants that use wood-residue based combustibles.
Level 1 SCAC Control Unit:
- Constant and modulating control of combustible feed according to demand;
- Control and modulate the exhaust fan to maintain stable pressure in the boiler and ensure proper heat exchange;
- Control and modulate primary and secondary air feeds to maintain stable combustion and minimise particle emissions into the atmosphere.
Level 2 SCAC Control Unit:
- Constant and modulating control of combustible feed according to demand;
- Control and modulate the exhaust fan to maintain stable pressure in the boiler and ensure proper heat exchange;
- Control and calibrate primary and secondary air feed to maintain combustion at the highest possible level of efficiency and minimise particle emissions into the atmosphere;
- Ensure optimal combustion (humidity, wood species, granulometry) since the combustion parameters are auto regulated based on data collected by the combustion gas analyser.