Compiled by Yvonne Andiva, Ann Kagumu and Torah Onyango
The deeper mines go the hotter it gets and in addition the limited air becomes less adequate for humans to breath bearing in mind the competition for oxygen created by running machinery and the contamination from dust and possible gas emissions such as methane that can be present.
To tackle mine ventilation miners have devised systems of ducts and pipes to allow the flow of air into and out of the mines in order to both regulate the temperatures, provide sufficient oxygen and expel unwanted gases and dust.
While in its most simplified form a ventilation system is basically a combination of pipes and ducts, fans, cooling and heating systems, and possibly air cleaning equipment, it gets more complicated when you consider the different issues you need to take into consideration when designing the right system for a mine given that no two mines conditions are completely identical.
Let’s look at some of the factors that will affect choice of equipment. To start with the cost and nature of the energy source available will greatly affect the range of equipment options, while the surface temperatures and humidity, rock strata temperatures and moisture content will have to be considered as well. The layout of the mine workings on the other hand will demand a certain mix of ventilation shafts, bulkheads and partitioning in order to ensure air quality standards are met for human health and safety.
To optimize energy use it is obvious that where there is no activity there is not much attention required as compared to those with activity and so sophisticated systems have been devised that make use of wireless sensors to monitor air quality and temperatures and control systems to ventilate only specific areas.
In all cases specifics of actual equipment to be installed should be obtained from the manufacturer or supplier along with maintenance and service support in order to avoid costly mine shut downs. In this feature we look at what is available to the industry.
TLT-Turbo mine ventilation systems
TLT-Turbo GmbH builds centrifugal and axial-flow fans for virtually any application. First-rate engineering, tradition and progress in air handling technology, and a worldwide support network have been the cornerstones of TLT-Turbo’s global renown as a fan and systems manufacturer for more than 125 years.
They provide a wide range of solutions for mine ventilation systems of leading edge technology, either working as exhaust or blowing, arranged horizontally or vertically, above or below ground including explosion proof if required. TLT – Turbo has the people, the services and global presence to help you through all stages of a ventilation project’s life cycle – from planning through design and commissioning to maintenance and service – to come up with energy-efficient and viable results.
First-rate engineering, tradition and progress in air and gas handling technology, and a worldwide support network are the cornerstones of TLT-Turbo’s global reputation as a fan and ventilation systems manufacturer.
On the strength of many pioneering developments in mine ventilation engineering, they have been supplying forward-looking products and solutions for more than 175 years. Today over 3000 axial flow fans for all field applications are installed with more than 500 mining fans currently in service in all major mining regions worldwide.
One and two-stage axial fans with impeller blade adjustment systems (under load) have been specifically developed for heavy-duty applications in the underground mining industry. Mine ventilation is a major source of potential energy savings. They are committed to achieving the best possible system efficiencies through effective aerodynamic designs and intelligent drive and control systems.
Other fields of application for the axial and centrifugal fans and systems: Thermal power plants, tunnel ventilation, wind tunnels and test stands, steel industry, mineral processing, chemical and petrochemical industry, cement industry, waste incineration, thermal drying, mechanical engineering, air conditioning systems, fire protection and smoke extraction, electronics, food processing industry, pharmacy, precision mechanics, construction of vehicles and ships.
The Beckair Ringjet and Clustajet
Beckair a division of Secomak Ltd. are international providers of pneumatic nozzles and compressed air technology for use in confined spaces and hazardous environments.
The Beckair Ringjet is a bladeless fan ideally suited for personal cooling in confined mining environment. The Ringjet does not require electrical power and has no moving parts, making it suitable for use in hazardous or potentially explosive areas.
The Ringjet design utilizes the Coanda effect to multiply outlet air flow up to 25 times the inlet flow, enabling the unit to produce a powerful flow of air with minimal input. The flow of air is easily changed by the user by loosening or tightening the screw thread. The range of sizes, from 12mm to 250mm throat diameter, provides outlet air pressures up to 1178scfm.
The lightweight unit is constructed from either stainless steel or anodized alloy and is capable of withstanding heavy handling. The Ringjet can be safely attached to the front of work wear or carried conveniently in the pocket.
The Beckair Clustajet is a bladeless ventilation and extraction unit designed for bulk removal of hazardous fumes and dust in potentially explosive or confined mining areas. The high suction Clustajet utilizes Ringjet technology to provide safe extraction of fumes and dust without any moving parts or the need for an electrical supply – making it fully maintenance free.
Capable of both extraction of hazardous fumes and insertion of air for conditioning and cooling, the Clustajet can be fitted with flexible hose for operation up to 25m without any loss of suction. Multiple units can be tethered together to provide extraction over longer distance. The direction of flow can easily be changed by reversing the unit, and the volume of air is simple to control using the fitted valve on the handle of the unit.
Jensen Ventilation AB produces and delivers ventilation tubes according to customer requirements for mines, tunnels and other underground work.
Jensen Ventilation AB uses a highly effective method of welding the material. The method was developed within the company and patented in 1981 in Sweden. The 40 mm wide weld seam becomes almost as strong and durable as the material itself.
Over the years the focus has been placed on being able to produce qualities that cater to different requirements for strength and construction. The result is reflected in today’s qualities JP 501, JP 551, JP 651 and JP 752. All are dimensionally stable, fire retardant and possesses a low coefficient of friction. Anti-static option is also available.
With the help of bends, Y-and T-tubes and reductions, all made from the strongest quality, Jensen Ventilation AB is offering a complete and reliable ventilation system.
Ventilation ducts consist of a woven or knitted textile made from polyester yarn coated on both sides with softened PVC (polyvinyl chloride), normally yellow on the outer side and on the inner side.
The polyester textile gives the ventilation ducts its mechanical strength. Different textile thicknesses are used in the different duct qualities. The textile is made in accordance with specifications provided by Jensen Ventilation, including for the number of threads per cm and type of yarn for warp and weft.
The coating on the textile makes the ventilation duct air and water tight, protects the yarn against UV radiation and chemical effects of light, plus it makes it possible to weld the individual sheets together into a circular duct. Thicker coatings provide better wear resistance. The coating consists of PVC, plasticiser, stabiliser, fire-retardant agents and pigments.
The ducting should always be stored on whole pallets. The ducting could be stored outdoors but should then be covered from dust, heat and the sunlight.
ECE-COGEMACOUSTIC standard axial fans
ECE-COGEMACOUSTIC, produce ventilation studies, design suitable solutions and manufacture ventilation equipment, notably axial fans for use in underground mines, tunneling and other underground works. Dust collectors also form part of their core products which can be either dry (filters) or wet (water pulverization) types.
ECE-COGEMACOUSTIC is certified to manufacture explosion proof ATEX IM2 type ventilation equipment, for use in coal and gaseous mines.
The range of ECE-COGEMACOUSTIC standard axial fans are capable of supplying an airflow rate of 2 – 230 m³/s (11,000 – 500,000 cfm) at a pressure rise of 250 – 7000 Pa (1” – 28” w.g.) . The fan can be comprised of one, two or three stage configurations. Various levels of sound attenuation can be provided in order enabling customers to find the just balance between budget and environmental requirements.
The mounting of auxiliary components such as inlet bells, outlet cones or duct storage cartridges is facilitated by the modular and normalised design of the components (ISO 6580-1981(F)).
A wide range of ventilation characteristics for a given nominal diameter of fan are attained through the use of advanced engineering in the optimisation of the impeller hub diameter in conjunction with the number and length of the blades. The blades are easily adjusted once the fan is at standstill.
Dust, generated by excavation works in enclosed areas, must be captured at its source in order to prevent its dispersion inside the underground network. This is the role of the ECE-COGEMACOUSTIC scrubbers. Their range offers units with airflow capacity of 3 to 25m³/s.
All of the ventilation equipment can be controlled by various types of electrical cabinets which are designed and manufactured in-house.
ECE-COGEMACOUSTIC designs tailor made ventilation solutions for each project. This begins with the analysis and understanding of a project’s parameters. The department makes use of two well-known 3D computer applications – VnetPC Pro and Advanced Ventsim, for the design and simulation of mining ventilation. The department also organizes special training courses for the customers’ engineers in the art of ventilation and the application of international standards – SIA 196, BS, AFTES…
After a solution has been approved by the customer, it is transferred to the production department. The product conception is optimized to suit the projects’ individual requirements. Integrated European parts with high electrical efficiency and technical excellence assure high reliability of our products. Each step of the production processes which is carried out by our fully skilled technicians and operators on modern CNC machinery is controlled by our quality assurance department. State of the art technology is used to integrate instruments and measurement devices in order to provide real-time monitoring and control of the ventilation equipment. Energy saving is always at the heart of their thinking and preoccupations.
SRK Consulting (UK) Limited
An efficient mine ventilation design is fundamental to any practical mine plan and to low mine operating costs. Their engineers use their wide experience of mine development and production operations to ensure ventilation plans can be implemented in a way that supports and enable a mine’s production targets. As part of SRK’s provision of mining engineering services they offer mine ventilation design for technical studies from greenfield to mine expansion projects, at scoping level to full feasibility study and as part of operational improvement studies. Using the latest ventilation modelling software, Ventsim® their trained engineers use mine plans and production schedules to simulate the ventilation network over a mine’s life to design the most efficient ventilation solutions that will provide a safe working environment, meet regulatory requirements and to minimize power consumption.
When the mine environment has particular challenges, such as extraordinary depth, high virgin rock temperature, the presence of gas or radiation, or long distances between intake and return, specific engineering such as mine air cooling, refrigeration or controlled partial recirculation can be required. All the key aspects of mine ventilation are modelled, including thermodynamics to determine the size of heating or cooling installations where required, and to specify fan size and location to deliver the right air flow around the mine for a safe working environment. SRK uses its global network to provide the best advice and engineering design to meet clients’ requirements.
THE HURLEY GROUP
They are an ISO 9002 Certified Company that has been providing the Canadian and International Mining, Milling and Construction Industries with quality products & services since 1976. They provide valued customers with the best products & services available. All of their equipment is fully reconditioned and/or rebuilt to O.E.M. specifications. The products they have include: O.E.M air & electric fans, large inventory of makes, models, sizes & hp. vent tubing & vent clips, inlet bells & screen, adapters, elbows, & wyes etc, silencers. All items sold as fully reconditioned and/or rebuilt, carry a warranty.
They have the HVT Adjustable Pitch Vane Axial Fan line which was designed specifically to blend aerodynamic performance and ease of application. These fans are suited for construction, tunneling, industrial and mining applications, from 1,000 to 300,000 cfm and 0.5” to 20” total pressure. Based upon over 25 years of experience with axial fan installations, the design of these fans has been refined in order to offer the most reliable, maintainable, and cost effective equipment in the industry. HVT offers a series of adjustable pitch vane and tube axial fans for construction, tunneling, industrial and mining applications. HVT has a fan to meet a wide range of applications.
They produce fiberglass duct and fiberglass pipe for use in industries including semiconductor fume exhaust, pharmaceutical, wastewater treatment, silicon wafer, solar cell, picture tube, and flat panel industries. While they offer a wide array of products to meet your needs, they specialize in producing fire safe duct. ATS, Inc. has been serving the semiconductor industry since 1978. They manufacture round duct in diameters from 2″ (50mm) to 120″ (3000mm) and oval and rectangular duct to meet customer specifications. All parts, even pattern field fittings, can be reconfigured and assemble with ease. Like a child’s building block set, ATS can be fully modified.
In a continuing effort to reduce installation time, they have invented the H-Collar Joining System. The H-Collar system builds on the ATS Internal Beaded Slip Collar’s success in providing a contiguous internal liner and as an alignment tool. But the H-Collar™ takes simplification in joining one step further. There are no external wraps to do. Now it is only necessary to apply the ATS ChemBond putty and slip the duct into the collar. Literally, this joint can be put together in minutes. Important Note–Like the ATS Slip Collar™, the ATS H-Collar™ is universal–it accepts any straight butt end. This allows the contractor to modify duct lengths on site without worrying about special preparations of duct ends. The H-Collar, pre-fabricated into one end of a section of duct, is called a U-Collar. By ordering duct with U-Collars, a contractor can install 60 feet of duct by making only two joints (and simple ones at that—without exterior wrap) Connections are made using the same methods for the H-Collar. Ordering U-collars on straight duct eliminates the need to do half the work! Ducts can be ordered with a U-collar on both ends of a 20’-0” duct or on one end of a 10’-0” or 20’-0” duct.
Vent clips are their one and only product. They keep an inventory on-hand that matches ones need. This means that they are able to provide a next day delivery. They are a manufacturer of high quality clips used for connecting flexible ventilation tubing. For use of most flexible ventilation products, VC516 are metal clips with attaching wing-nut screws that are tightened down on sewn-in wire rope couplings which create a tight seal without damaging the ventilation tubing fabric.
Each clipping is constructed of 1/8 metal and is assembled using minimum grade 2 5/16 coarse thread carriage bolts and matching easy spin wing nuts. All clips are individually and inspected and packed in boxes of 100 before being shipped to your location.
Xiamen ZhongXingLong Air Conditioning Equipment Co., Ltd.: is a specialized manufacturer of air conditioning equipment in China which was established in 1997. With years of experience, the firm has concentrated on developing a comprehensive range of ventilation products.
Through the efforts of their research and development department and inspection department, the company has gained various intellectual properties to protect our designs both in the domestic and the overseas markets.
Their popular products include: purification system equipment, air filter, spiral tubingflexible ducts, air diffuserair damper, drain smoke tap and noise control series.
Shandong Grad Group
Is a firm enterprise specializing in the manufacture of central air-conditioning and FRP compound material products in China.
In addition Grad Group is one of the executive director units of China Refrigeration and Air-conditioning Industry Association, a member of China FRP Industrial Association and China Association of Automobile Manufacturers and the chairman unit of Dezhou FRP Association.
The company has developed into a modernized large business group integrating R&D, design, manufacture, checkout, sales, installation and maintenance of central air-conditioning, ventilation, and FRP products.
Shanghai Richeng Electronic Co. Ltd
A well established company is a professional in manufacturing wiring duct, wire duct. They are experienced and technical in this line, providing wiring duct, pvc trunking, wire duct, wire trunking,cable trunking,flexible wiring duct, wiring duct cutting tool which are used in industrial design, machine design and such electric distribution box to arrange the wires.
Professional in serving the foreigner invest companies and the domestic companies who need wiring duct, their products are approved by the international certificates of, CE,ROHS.
Shanghai SIGEA electric
Is a firm that focuses on the industry environmental control filed and a leading supplier of cabinet environment and the related products in China including textile, wind power, steel, telecom, packaging and printing equipment, industrial sets of office automation equipment and environmental control and optimization.
After development of nearly 20 years, the company has already became a professional manufacturer which integrated research &development, production, sales, has advanced production technology, quick delivery process and scientific management system, and take Shanghai as the center, radiated in whole China area, has sales agents and after-sales service in every large and small cities.
Is a flexible and dynamic company committed to providing unparalleled quality in new equipment and service to the underground metalliferous mining and civil tunneling industries in Australia. Their specialties include: Design, Manufacture, Hire and Supply of High Efficiency Axial Flow Fans, Spare Parts and Accessories for Underground Mining and Tunnelling.
The company currently has fans in more than 21 countries and with more than 25 years experience in the industry. Clemcorp Australia is the company to trust with engineering your ventilation solution.
They have exported fans to mine sites in the DRC, Mali, South Africa, Ghana, Tanzania, Egypt, Burkina Faso and Zambia in recent years.
Xiamen ZhongXingLong Air Conditioning Equipment Co. Ltd
Shandong Grad Group Co. Ltd
Shanghai Richeng Electronic Co. Ltd
Shanghai SIGEA electric
THE HURLEY GROUP
Contact: Bart Hurley
Contact: Jeff Shea
Contact: william martin
List of contributors
Jensen Ventilation AB
Nabil EL HAJJAM
SRK Consulting (UK) Limited