** Shares of Environmental Group EGL.AX rise 6.3% to A$0.255, their highest levels since February 20

** The emission control systems provider agrees to acquire Advanced Boilers & Combustion Pty Ltd, an industrial boiler service and manufacturing business, for A$5.5 million ($3.45 million)

** Co says acquisition represents a major expansion in its sales and service offering to the industrial boiler industry, complementing EGL Energy's existing business

** About 1.9 mln shares change hands, 2.5x the 30-day average of 753,475

** Stock down 19.1% YTD, including current session's moves

($1 = 1.5939 Australian dollars)

(Reporting by Manasi Dasa in Bengaluru)

((Manasi.DasaSundeep@thomsonreuters.com;))