Document XRzj7wKRGQkXR2z6jnM2LnOky

1 New Boiler-Plant Design Features Oil-fired plant, built on site of coal-fired one without inter rupting process service, gives needed capacity, reduces steam casts. Adequate meters and automatic combustion con trol permit plant engineers to obtain practical boilertest performance every day If JAMES A KEARNS C<mlrt| Engineer, Montreal, Canola Poa ov*s 50 tears Melchera Distil leries ha# been at BerthJervilte, on the St Lawrence River about 50 miles from Montreal. The plant has beenvmodem- MEW BOILER PLANT hat two 8<MXKNb-per-hr boilers, designed for BOO pel but operated at IBS pel and 429 P total temperature. One eld eoal-flred boiler, hown between the two new ones, was retained for operation In emergencies Iced several times to maintain high standards of efficiency and the quality of Its products--high-grade Scotch and latter marketed for farm-stock feed. In enhances ihe importance of reliable con rye whlaUea, London and Geneva gins, winter, steam demands for building tinuous operation. Lost production can- induitrUI and potable alcohols from heating are heavy because for tong peri not be supplied by another plant, as with both grain and molasses. Latest im ods outside temperature remains around companies operating several plants. provement la complete modernization of zero, and at times drops to 30 F below, New Unite Oil-Fired. Either high- tho boiler plant, something that could or lower. . grede cool or fuel oil could have been not be done until now because of war Steam demands for certain distillery selected for firing the new boilers, but restrictions. processes fluctuate widely. Grain cook even though the old boilers were coal Daring the war, as in. all Canadian ers and some stills operate on live steam fired, oil was chosen for several rea dlstUleriea, total production capacity with requirements that may suddenly eons. It is as economical a fuel as coal was devoted to manufacture of indus vary as'tnuch as 50%. Other stills call at the plant location. It eliminates coal trial aloohol for synthetic rubber and for continuous operation and.uninter dust around production departments chemicals. Hie return of peace found rupted steam supply. where cleanliness is a prime considera the. steam plant practically worn out. The stills require large quantities of tion. Either coal or oil can be received ' Aged equipment had been forced con- cooling water, which is pumped from by railway, but oil is much easier to rinuotuly for maximum production, and the river. Because of difference in water store and handle than coal, particularly maintenance had been -inadequate be temperature about three times as much in winter during periods of heavy snows cause of the difficulty of holding expert*" water is required-for-the-same producenoed operators, and making-neeeasaryr "Uon in'suramer-as'in-wlriier.-'For this repair* and' replacements. Accordingly, reason^ as much annual production as and subzero temperatures. Handling .and storing .olLrgquires much leas ef fort than coal does,' an important con the company'launched a modernization possible ft scheduled for the fall, win sideration under prdisent conditions. An program, and retained (he writer a* con ter and spring months. Ceneral plant oil-fired plant is simpler in design and - sulting engineer to design and super overhaul and vacations take place in the operation, and avoids tho large fuel vise die construction of a new boiler summer, a period of light operations. storage required by coal. Oil firing Is plant ` Taking consideration of these and well adapted to handling the widely Stias Osmonds. A distillery re other (actors lad to a boiler plant de fluctuating process and heating steam quires large quantities of medium- and sign that would have high efficiency and demands. low-pressure steam for atiU operations, reliability, and be simple to operate. Steam Pressure Sotecrien. Power, grain oooking, regulating math-vat tem The fact that this distillery is the only proceas-and-heating steam for the plant peratures and drying spent grain, the one operated by the company further could hnvo been supplied by Installing 66 (4lj POWER January 1948 Reliability and Simple Operation INDICATING AND RECORDING MCTBRSr A full complement of these Instru ments haa been provided for the bollora. They are also equipped with automotlo control to maintain high operating efficiency over wide range of steaming load high-pressure boilers and backpressure bleeder turbines. But these units re- . quire a considerably larger investment in equipment, a much more complicated plant to operate, and a more highly skilled operating staff than a simple boiler plant. The management wonted to avoid these responsibilities because there were no compensating factors here lhat would make them worth-while. Power, which can he purchased from the local utility at low rates, is supplied from a large hydroelectric system. Thus these rates can be expected to remain fairly constant no matter what may Hap pen to fuel costs. Therefore provisions were not made in the n w boiler-plant design for (mure power generation. This led to selecting hmlers to provide steam ot s pressure and temperature required lor process and heating only. A New Bedding, (i was desirable to build the new boiler plant on the aite of the old one, which contained three watertubc holler, of 2500 sq It and one hrt of 1400 q ft of heating surface, all hand fired. Immediate and future steam demands indicated that the new boiler capacity should be about double that u( tho old in two new units with provision (or a third when re quired. A greatly enlarged plant had to be built on the site of the old one without interfering with distillery operations.Thc first step in this program was to construct around the old plant a new building, designed by Architect Charles David, of suitable size to house three new boilers, and their auxiliaries and control equpment (plan at top of p. 08). With completion of the new build ing, tho old hoilerhouse woe removed to permit installation of thei new boilers. Construction of the new plant was con siderably simplified by not having to provide a cual bunker and other storage facilities. Tho plant was so located that when one old hrt boiler was removed space was available for the first new one. When (his unit, as well as a new stack for three boilers, was erected and in op eration it was cut into service; then tho two old watertube boilers in the op posite end of the plant were removed and the second new boiler inslalted. Photo on p 66 shows the interior of the new boiler plant where the one remaining old boiler can be seen with a ladder in front of it This unit has been retained in standby service for coal firing if, because of a strike or other cause, the fuel-oil supply should fall temporarily. Future plant expan sion includes Installation of a third boiler between the two new ones where there will be ample apace when the old one is removed. The new plant was designed with this expansion in view, which would provide a peak steaming capacity of 100,000 lb per hr. Two New Bollora. Designed for 200 pai, each of the new units with waterwall and slag-screen furnaces, has a con tinuous steaming capacity of $0,000 lb per hr and will operate ot 125 psi and 50- to 75-F superheat, a total temper ature of 400 to 425 F. Each unit has a maximum 2-hr steaming rate of 35,000 lb per hr. To meet requirements for a boiler and furnace efficiency of over 84%, tubular air heaters were provided, designed to heat the combustion air from 60 to about 500 F. Bollar Auxiliaries. To simplify plant design and operation induced-draft fans were omitted and draft provided by a forced-draft fan on each boiler and a 17S*ft stack that serves the two. To compensate for the absence of induceddroft fans and to obtain high efficiency the boilers have' been designed for low draft losses by keeping the gas velocities comparatively low through them. Natural draft was favored by maxi mum steam demands coinciding with the higher stack draft available In winter when outside temperatures are lowest With 80-F outside temperature*, stack draft is ample to maintain a furnace pressure of --0.1 in. of water when gen erating 25,000 lb of steam per hour. In summer should (he boiler have to oper ate temporarily at a higher steaming rate, a damper permits bypassing pari of the gas around the air heater with a slight reduction in efficiency (see bot tom of p 68). During winter outside temperature is such that draft la ample under all load conditions without by passing the air heater. Two forced-draft vartable-eapaeity mechanical atomization burners, one above the other in the furnace front, fires each boiler with bunker-C fuel oil. At present oil it an economical fuel for many applications In this part of the Province of Quebee but in the future the price differential may favor high- POWER January'1948 IS) 67