Abstract: An automatic fire extinguisher and alarm apparatus, particularly suitable for use with waste receptacles, which discharges fire extinguisher fluid when exposed to a fire and sounds an audible alarm. Fire extinguisher fluid is quickly discharged from a reservoir onto the fire when heat from the fire melts a fusible alloy plug. A second reservoir contains a partially gaseous alarm agent, and is connected through a valve to a vibrating diaphragm gas horn. The valve stem is connected to a diaphragm separating the two reservoirs. When pressure is lost in the first reservoir upon discharge of the fire extinguisher fluid, the pressure of the alarm agent in the second reservoir moves the diaphragm and valve stem and opens the valve, allowing alarm agent to be discharged through the gas horn, raising an audible alarm.

Abstract: The following specification discloses a process and burner for combusting fossil fuels such as coal to provide low SO.sub.x and NO.sub.x emissions. The process includes pulverizing the coal together with an alkaline material, such as limestone in an amount calculated to provide an alkaline metal stoichiometric equivalent of one to seven times the stoichiometric equivalent of the sulphur contained in the coal. The resulting pulverized coal-limestone mix is then combusted under fuel rich conditions. For example, 25% of the theoretical air required to combust the coal is preheated and injected into the combustion zone together with the pulverized coal-limestone mixture. The primary or transport air is swirled to increase mixing and to stabilize the flame. Preheated secondary air is introduced to the combustion zone. The amount of the preheated secondary air amounts to approximately 40% to about 100% of the theoretically required air.