This Presentation was presented at the 5th Eilat-Eilot renewable energy conference at the ‘Advancing Sustainable Energy Implementation in Israel through Policy and Practice’ panel.
Y. Hain1, B. Chudnovsky1, N. Rappoport2, Mordechai (Modi) Reshef2, S. Baitel3
1Engineering Division, Israel Electric Corporation (IEC), Israel
2Generation Division, Israel Electric Corporation (IEC), Israel
3DOR Chemicals, Israel
Over the past years there has been a dramatic increase in the regulatory requirements for low emissions from both new and existing utility boilers and gas turbines. Traditional methods of reducing NOx emissions, such as: modification of the firing system (DLN – Dry Low NOx), addition of water into the firing system (WLN – Wet Low NOx), and/or post combustion treatment of the flue gas to remove NOx are very expensive.
One of the attractive alternative fuels for combustion in the utility boilers and in stationary gas turbines may be Methanol. Using Methanol has become an important solution for emissions compliance due to its unique constituents and combustion characteristics. Methanol may be referred to as anenviro fuel. The clean burning characteristics of methanol are expected to lead, on top of low emissions, to clean pressure parts, turbine blades and lower maintenance than with fuel oil.
Here, we shall focus on presenting results of a basic test run by a joint venture of IEC – Israel Electric Corporation and Dor Chemicals, of burning Methanol in a jet Gas Turbine -FT4C TWIN-PAC 50 MWedesigned and produced byPratt & Whitney. The test was run in an IEC site atCaesareaand it was conducted in a way where the GT was started with no. 2 fuel oil (gas oil) and later Methanol was introduced into the machine gradually while the no. 2 oil flow was closed until the engine was running using methanol firing only. .
The experiment tested different GT loads during methanol firing. The results
presented clearly show that with minor low cost fuel system retrofit methanol firing leads to significantNOx,SO2andparticulatesemission reduction:
– NOxemissions were reduced more than 75% and are equal 75 mg/dNm3 at 15%O2.
– SO2emissions were reduced to zero.
– Particulateemissions were around1.5mg/dNm3 at 15% O2 compared to around 14.
However it should be noticed that Methanol has a heating value which is half of the no. 2 oil. This enabled the machine to supply approximately half the load (actually due to some reserve in the flow parameters design, 60% of the load was achieved). It means that in order to restore the machine’s capacity it is needed to double the flow rate of liquid fuel running into the machine and into the firing chamber.
A system of external high pressure pumps and aVSD–Variable Speed Drivewith a new control system was designed to allow for the required high Methanol flow.
A description of the system and the setup for running a full scale operation test which is planned to be conducted on a same GT inEilatwill be described. This will be done in order to show feasibility of such a system, to reassure the excellent emission reduction all along the load scale, and in order to gain some experience of a long term operation.
Modi- Methanol as a low cost alternative fuel