Setting new standards
MTU Friedrichshafen has launched the new generation of its successful Series 4000 diesel genset engines. The new engine for power generation applications is even cleaner, more economical and more powerful than its predecessor, setting new technical standards for genset engine NOx values in the 1.2-3.5 MW range.
With NOx values below 1700 mg/Nm3 of exhaust gas across a range of 50 to 100 per cent of rated power, the new genset engines undercut the previous version by 15 per cent. The new Series 4000 diesel engines achieve these NOx values without exhaust after-treatment. That means they are setting new standards in 50 Hz applications while the 60 Hz engines easily meet the stringent emission limits demanded by US EPA Tier 2.
The new MTU Series 4000 diesel genset engines, with NOx values below 1700 mg/Nm3, set new technological standards
The new combustion settings on Series 4000 genset engines also reduce particulate emissions to below 50 mg/Nm3, which represents a significant step in the development of ecologically-sound genset engines, especially as far as the reduction of fine particulate in densely populated areas is concerned. And at less than 300 mg/Nm3 of exhaust gas, carbon monoxide values are just half that of the previous engine version.
The new engines are also more powerful than their predecessors. Depending on cylinder configuration, the new engines produce 1910 kW, 2500 kW or 3490 kW making them 13 per cent (16-cylinder version) and 16 per cent (12 and 20-cylinder versions) more powerful than the previous units.
Spark-free gas engine
MAN B&W Diesel AG has developed a new gas engine featuring a new start-up and ignition system that does not require spark plugs. The new engine – designated 32/40PGI – has been operating at the company’s Augsberg facility for a year and was officially launched at Power-Gen Europe in Cologne in June.
The new injection system, known as Performance Gas Injection (PGI), enables the advantages of a diesel engine, i.e., high power density and high efficiency, to be incorporated into a gas engine. It also enables low emissions to be achieved without the need for after-treatment to reduce nitrogen oxides.
In the PGI process, a small quantity of ignition gas is injected into a pre-chamber separate from the main combustion chamber. There it is ignited on a hot surface and initiates the ignition of a lean gas-air mixture in the combustion chamber. This lean mixture contains a high excess of air so that, in combination with an effective method of ignition, efficiencies are achievable approaching those of a state-of-the-art diesel engine.
Canary Islands turn waste into energy
Located in the Atlantic Ocean, the Spanish Canary Islands are a destination for millions of travellers each year. As a collection of islands totaling only 7446 km2, and with tourism a high priority, disposal of wastewater and solid waste is an important environmental and political issue throughout the Canaries.
One solution to the waste issue is to process waste in a digester that produces biogas, such as at the new Salto del Negro municipal waste treatment plant in Las Palmas de Gran Canaria. The plant processes garbage collected from Las Palmas de Gran Canaria, a city of 380 000, as well as from surrounding towns and villages.
The biogas digester at the Salto del Negro waste management facility processes 75 000 tons of biowaste per year, turning it into methane gas that is used to generate electricity and heat
The primary purpose of the facility is to process the waste produced by the residents and visitors in Las Palmas de Gran Canaria and neighbouring cities. However, the gas produced is used to power a combined heat and power (CHP) system. “The facility has a processing capacity of 200 000 tonnes of waste a year. The capacity of the biogas digester is about 75 000 tonnes of waste a year,” says Jose Melgarejo, business development manager for Cummins Power Generation.
The CHP system uses the digester gas (65 per cent methane) to generate both electric power and heat. The exhaust heat from the engines is used by the treatment plant to accelerate the anaerobic processes in the digesters, while excess electricity not used in the plant is sold to the local utility – earning a biogas-derived electricity premium.
The CHP system at the Salto del Negro waste management facility consists of two 1370 kW GQMA low-Btu gas generator sets, a PowerCommand Digital Master Control and low-voltage switchgear, all built by Cummins Power Generation. These low-Btu generator sets are specially designed to run on dilute solutions of bio-derived methane gas produced by municipal landfills, sewage digesters and coal seams. A third generator set is scheduled to be added within a year.