Household Waste Incineration

Control of the Combustion Process of Household Waste Incineration

Every year, 2.12 billion tons of waste is generated globally. While over 75% of it is recyclable, we only recycle 30%. Waste-to-energy is a technology which is more and more used  to generate energy (power and heat) from the sustainable management of municipal solid waste, 50% of which is considered as renewable. Waste incineration involves the combustion of organic substances contained within municipal solid and industrial standard waste material. Each ton of waste that is burnt and converted to energy can power a household for a month.

Considering what is at stake, designers as well as operators of waste incineration plants continuously look for ways to improve their efficiency. Solutions exist. Among them, thermography cameras support consistent and reliable monitoring of the incineration equipment, and provide numerous data which can be fed in real time into control systems to optimize the operation of the installation.

Needs of Waste Materials Incineration

A modern incineration plant shall ensure complete combustion of all organic material contained in waste while minimizing emissionsmaximizing recovery of heat generated in the furnace and optimizing maintenance and operating costs.

To be able to burn materials that are sometimes very solid, incinerators must reach a temperature which is usually between 850°C and more than 1100°C. This temperature and its distribution must be controlled to avoid the creation of hot spots where concentrated heat might damage the grate or the walls of the furnace, and to ensure that heat is released at the proper location to be collected and transferred efficiently to the boiler. As they measure temperatures at any point in the image, HGH thermography cameras allow you to map temperatures in the combustion area and to locate hotter or cooler places.

Pyroscan soft flame front detection

Areas of interest can be monitored specifically and associated to temperature alarm thresholds to warn the operators when the risk increases for damage to the furnace, emissions increase above critical values, or waste is burning too fast or too slow.

Waste Incineration plant diagram

Slag and ashes at the outlet of the grate shall not include residual organic materials when incineration is complete. An efficient way to ensure such compliance is when the combustion stops early enough before the end of the grate, but far enough from the inlet of the furnace so that temperatures are evenly distributed over the grate, and heat is released progressively and at the proper location to ensure efficient transfer. The accurate control of the location where the combustion stops, or flame front, is of paramount importance for the effective operation of the installation. HGH has developed a dedicated algorithm specially designed in partnership with worldwide leaders in waste incineration to provide accurate and real-time flame-front detection in furnaces of waste-to-energy plants. The location of flame front is transferred in real-time to the furnace control system which will adjust the speed of the grate and the airflow in various areas, which will turn on burners if needed.

The many measurements made at a high rate by HGH cameras are pre-processed and made available in real time through standard data interfaces to be used directly by control systems. Such continuous, small-step adjustments of the operating point of the furnace minimize energy consumption and mechanical constraints in the actuators, thus reducing operating and maintenance costs. The possibility to implement high-level algorithms and expert systems which will further improve the overall performance of the installation.

Waste incineration plant: Pyroscan and Pyroscan-U thermographic cameras are respectively used inside and outside of the combustion chamber to monitor the combustion process.

HGH Solution - Ruggedized Cameras

HGH heavy-duty camera PYROSCAN is available in two models

PYROSCAN is a temperature-resistant camera which can be fitted with an automated insertion-retraction mechanism, allowing its water-cooled endoscope to be inserted inside furnaces to capture images close to the area of interest, without masking or attenuation of signal.

PYROSCAN-U is a ruggedized camera which is installed outside the high temperature burning zone of furnaces, looking at the calcination area through a standard window. It works at ambient temperature without any cooling system, and its compact design supports implementation in space-constrained areas.

Both versions of the system capture images that are processed by a dedicated powerful software, providing an interface with the DCS (Distributed Control System) in real time. The intuitive HMI of the system displays enhanced visible and thermal images, and provides the user with a complete toolbox to analyze data history and trending, temperature distributions and profiles, to record and replay temperature data for further in-depth analysis.

Benefits for the User

  • A high-performance system, suitable both for direct use by the operator and for coupling to DCS for automated control of furnaces
  • complete toolbox including algorithms specifically developed for incineration furnaces
  • Low cost of ownership: simple maintenance, minimal infrastructure and hardware costs
  • simple and intuitive HMI, quickly and easily available at the operator’s fingertips
  • Available in different versions and configurations to adapt to any plant configuration and constraints
  • Quick and easy setup: the system mainly relies on Ethernet or fiber optics connections

3 Key Points

Control of the combustion process

Temperature mapping

Optimization of maintenance and repair costs