MAPLE SIRUP PRODUCERS MANUAL 



117 



Figure 125. — A large central evaporator plant located at 

 Anawa, Wis. Some plants are large enough to make 20 

 or more gallons of sirup per hour. 



L«>4-atioii 



The site for a central plant should be cai-e- 

 fully chosen. Some of the factors to be consid- 

 ered are: 



(1) It should be centrally located in relation to 

 the sap-producing farms. 



(2) It should be on an improved road, prefera- 

 bly at an intersection. The road should bear 

 considerable nonlocal traffic. 



(3) It should have adequate space for drive- 

 ways for delivery of sap. 



(4) It should have an access roadway from the 

 main road and off-road parking areas for visi- 

 tors (customers). 



Size 



Like other industries, the size of the central 

 evaporator plant will be governed by a number 

 of factors that can readily be determined. Un- 

 like other industries, the central plant can eas- 

 ily be expanded to accommodate increased de- 

 mands because of the relative simplicity of 

 equipment and plant design. 



The initial plant must be large enough so 

 that the volume of sirup produced will yield 

 reasonable returns on the invested capital and 

 so that labor will be used economically. These 

 two factors will be determined by the cost of the 

 sap, the number of hours per day the plant is 

 operated and the length of the season, the 



number of man-hours required to operate the 

 plant, the output, and the price of the finished 

 product. These factors, in turn, depend on the 

 size of the evajwrators, the density f Brix) of 

 the sap, and the efficiency of the plant. 



Since the plant handles liquids (sap and sir- 

 up), it can be completely automated. The extent 

 of automation will be governed by the size of 

 the i)lant and the budget. The cost of producing 

 a gallon of sirup decreases as plant size in- 

 creases. 



An evaporator plant building of shed roof 

 design permits easy expansion. The shed roof 

 building can be doubled in size by adding three 

 walls to convert it to a gabled roof building. The 

 building must be large enough to permit easy 

 access to the evaporators and other equipment. 

 The materials should be easy to clean, such as 

 concrete floors, smooth walls, and built-in cup- 

 boards and resti-ooms. Provision should be 

 made for a candy kitchen and a salesroom. 



The most common type of central evaporator 

 plant uses oil heat to evaporate the sap in tlue 

 pans, each of which is independently installed 

 on its own arch with its own oil burner (see p. 

 59). A coil or tube of high-pressure steam is 

 used to heat the finishing pan, which is also 

 mounted on its own support (fig. 126 and chart 

 23). 



PN-1822 



Figure 126. — Interior of a modern central evaporator 

 plant at Bainbridge, N.Y. Oil heat is used to evaporate 

 the sap in the four flue pans and high-pressure steam 

 is used at the finishing stage. 



