ANNEX A Descriptions and Photos

Transcription

1 ANNEX A Descriptins and Phts Cmpnent One: Hrizntal autclave with biler The autclave is designed t treat infectius waste by expsure t steam at temperature f up t 130ºC and abut 1.7 bars. The autclave has a hrizntal inner cylindrical chamber (abut 200 litres) f stainless steel enclsed in an uter cylinder f mild steel (shwn in green in the phts). It has a dish-shaped back at ne end and a dr n the frnt ther. The dr is a steel plate cnnected by hinges t the uter cylinder. The dr has a wheel that cnnects t finger-like rds (shwn in red in the middle phts). When the wheel is turned, the fingers radiate utward until the ends f the fingers fit tightly int hles n the uter cylinder. A ring is welded arund the muth f the autclave s inner cylinder and fits tightly between the tw cylinders. A silicne gasket is placed in the ring and as the dr wheel is tightened, the dr plate presses against the gasket in the ring t seal the inner chamber. The tp f the chamber is cnnected t a pressure gauge and tw safety relief valves which autmatically pen if the pressure exceeds abut 2.5 bars. The frnt bttm prtin f the inner chamber has a pipe that acts as a cndensate return pipe ging dwn t the biler underneath. A thermcuple is inserted just under the autclave in the cndensate return pipe. The back tp prtin f the inner chamber has a pipe that is cnnected t the back f the biler underneath. The biler is a stainless steel cylinder with a pipe at the back tp prtin t bring steam t the back wall f the inner autclave chamber. The biler has a pipe at the frnt bttm prtin t return cndensate frm the autclave t the biler. There is a heating element running hrizntally near the bttm f the biler. The heating element can be remved and sealed s that the biler can als be heated thrugh a plate underneath it by a gas stve. A water-level sight glass is munted n the frnt r side f the biler t ensure that there is sufficient water inside the biler. There is als a lw water level sensr in the biler. A simple cntrller reads the temperature frm the thermcuple and cntrls the pwer t the heater. The cntrller cuts ff the heater if the water level becmes t lw. The biler and pipes are cvered in insulatin. The entire system is munted n a steel frame (shwn in yellw in the phts). Left t right: Frnt f the autclave and biler munted n a pick-up truck, side view f the autclave and biler, clse-up f the autclave dr, clse up f the cntrller Hydraulic cmpactr with bailing system The hydraulic cmpactr is intended t cmpress waste after it has been treated in the autclave. The cmpactr is a hrizntal rectangular steel structure with a hpper at the tp n ne end f the rectangular chamber. The hpper has a lid (nt shwn in the phts) with a cntact sensr that prevents the cmpactr frm perating if the lid is pen. Inside the rectangular structure is a vertical steel plate linked t a hrizntal pipe that is mved frward r backward hydraulically using a cntrller. The vertical plate cmpresses any waste placed int the hpper. Running hrizntally alng the sides f the

2 rectangular structure are tw pipes with slits. Inside each pipe is anther smaller diameter pipe with a slit. During cmpactin, the inner pipe is manually rtated s that the slits d nt align. This prevents waste frm getting int the pipes. The pipes are used t pre-thread baling wire r strap. At the ther end f the cmpactr is a hinged dr that is kept clsed and acts as the resisting plate. The dr is reinfrced and has a hrizntal slit in the middle. Attached t the utside wall f the dr is a remvable mechanical hand baler. After the full lad f waste has been cmpacted and while the cmpacting plate is fully extended t keep the waste cmpressed, the tubes alng the sides are rtated t allw the baling wire r strap t wrap arund the cmpressed waste. The wire r strap is als pulled ut thrugh the frnt slit f the dr and attached t the mechanical hand baler, which has a ratchet t tighten the wire r strap and a hand crimp t jin the ends. Baling the waste prevents scavengers frm pening the waste in a landfill. Left t right: hydraulically-perated cmpactr, clse-up f integrated baling system attached t the frnt dr, back f the cmpactr shwing the hydraulic mtr and cntrller, clse-up f the hpper Left t right: hpper shwing the cmpacting plate mving frward, hpper shwing full extensin f the cmpacting plate, frnt dr pened with baled waste being ejected Cmpnent Tw: Mechanical Needle Destryer The mechanical needle destryer is intended t cut the needle prtin f a syringe, thereby separating the needles frm the plastic barrel. The device is cmprised f tw stainless steel bxes sitting n a metal frame. The smaller bx is used t d the cutting and has a cntainer inside t cllect the needles. The cntainer is slid int place befre use. The bx has a small hle n the tp centre where a needle is placed (the phts shw the hle near ne side but it shuld be in the centre). Inside the bx is a cutting assembly cnnected t a handle. When the handle is mved dwnwards, a cutting bar mves alng the inside tp f the bx t cut the needle while a secnd bar bends the needle t prevent it frm being reused. The needle then falls int the cntainer. The cntainer has a large hle thrugh which the

3 needles fall. The large hle is cvered by spring-actuated lid which keeps the hle pen while the cntainer is in the bx and which clses the lid when the cntainer is remved. This keeps needles frm falling ut when the cntainer is taken ut and transprted t the autclave. The larger bx als has a large hle thrugh which the plastic prtins f the syringe are drpped. The large bx can be remved when full s that the plastic prtins can als be sterilized in the autclave. Left t right: needle destryer shwing the handle and the needle prtin f the syringe inserted int the hle f the small bx, anther view f the needle destryer shwing the large bx fr cntaining the plastic prtins, the cntainer f the small bx fr the needles with the spring-actuated lid and hle Cmpnent Three: Large and medium aluminium cntainers The large and medium cntainers are made f aluminium and have a semi-cnical shape that is tapered s the bttm is slightly smaller than the tp t allw the cntainers t be stacked n tp f each ther. The half cne shape allws tw cntainers t be placed side by side inside the cylindrical autclave chamber. Bth cntainers are made the same way with the nly difference being the sizes. The large cntainer has a height f 500 mm and the small cntainer is half that. The cntainer is made frm ne aluminium sheet cut frm a template prvided by COET/UDSM. The cntainer has a water-tight vertical duble seam alng the length f its back. The bttm f the cntainer has a cncave shape with a water-tight seam and the cntainer stands flat n its edges. There are tw reinfrcing grves arund the cntainer ne near the tp and anther near the bttm. The muth f the cntainer has a curl with an inside wire t prvide a gd seal. Arund the tp f the cntainer are wire latches which hld the lid tightly. Left t right: frnt f the cntainer painted with the bihazard symbl and shwing sme f the latches; cntainer shwing the lcatin f tw reinfrcing grves ne near the tp and the ther near the bttm; tp view f the cntainer (withut latches and

4 reinfrcing grve) shwing the tapered semi-cnical shape; tw cntainers placed inside the autclave The lid (nt shwn) als has a semi-cnical shape and sides t fit n tp f the cntainer. They are designed with hles and a special assembly which plugs the hles when the cntainer is being transprted and pens the hles when the cntainer is placed inside the autclave. The lid als has a reinfrcing grve. Small aluminium sharps cntainers The small sharps cntainer is intended t stre syringes that have nt been destryed. It is intended fr use with an autclave. The cntainer is a rectangular 9-litre tapered bx made f aluminium and leak-prf at the bttm. The lid has a hinge at the back, anther set f hinges in the middle, and a latch in the frnt t keep it clsed when nt in use (ideally the frnt latch shuld allw fr a lck, nt shwn in pht). When the frnt half f the lid is pened, it shws an upside-dwn V-shaped flap inside the cntainer. The flap is balanced s that any syringe placed n the flap will cause it t flip pen and allw the syringe t fall inside. There are stps n the flap t keep it frm pening if the cntainer is accidentally drpped. When all the latches are pened, the entire lid pens up alng the back hinge. Left t right: sharps cntainer as seen frm the frnt; sharps cntainer with the frnt lid pen and a syringe being drpped n the flap; sharps cntainer with the lid pen shwing the inside flap

5 ANNEX B Required Manufacturing Equipment and Skills Cmpnent One: Hrizntal autclaves with bilers and hydraulic cmpactrs with bailing systems. Manufacturing Equipment Cutting tls fr bth stainless steel and mild steel, including a blade shear r squaring shear machine Rll-bending machine fr bending 1-2 mm stainless steel and mild steel plates Tungsten-inert gas (TIG) arc welding r gas-tungsten arc welding (GTAW) equipment fr stainless steel Metal-inert gas (MIG) arc welding r gas-metal arc welding (GMAW) equipment fr mild steel 10-tnne press fr frming metal rds and plates Heavy-duty lathe fr shear spinning (pwer spinning r rtfrming) with a dished mandrel t create a dished head fr the bttm f the vessel and biler; r alternately, the dished head can be fabricated in a 30-tnne press Thread cutting dies fr frming pipe threads Drilling jig fr bring hles Oxy-acetylene flame cutting set with accessries t allw cutting f perfect cycles up t 0.7 mm diameter. Manual Metal Arc Welding (MAW) fr welding up t 10 mm mild steel plates, and angle bars. Hand grinder with cutting disks. Lathe machine with a minimum swing f 0.35m radius. Manufacturing Skills Metal frming and metal cutting prcesses including cld wrking f stainless steel and mild steel Designing f tls and fixtures fr different types f wrkpieces Fabricatin including welding using metal arc, and specialized welding including MIG and TIG welding Turning using a lathe machine including prper wrk-hlding design fr rings Frming f stainless steel and mild steel n presses r metal spinning n lathes

6 Drilling, reaming and threading f stainless steel and mild steel Designing f electrical and electrnic cntrl circuits including installatin f thermcuples, resistance heaters, water level mnitrs, and pressure gadgets; cnnecting sensrs t simple electrnic cntrls and pwer surces Designing and installatin f hydraulic cntrl systems and cnnecting hydraulic circuits Painting f metal surfaces using a stencil (the bihazard symbl stencil t be prvided by COET/UDSM) Cmpnent Tw: Mechanical needs destryers. Manufacturing Equipment Manufacturing Skills Shearing machine fr cutting stainless steel sheets. Welding machine t weld stainless steel sheets. Lathe machine t male cutting lever (handle) and ther parts f the cutting mechanism. Hammer and vice fr bending sheet metal parts such as the blade. Drilling using a drilling machine Riveting Grinding t debur sharp edges and crners Milling machine fr sltting f blades Welding Bending and cutting steel Riveting Turning using lathe machine Thread cutting using tap and die; and lathe machine. Drilling Sltting f sheet metal parts Cmpnent Three: a) Large aluminium waste cntainers b) Medium aluminium waste cntainers c) Small aluminium sharps waste cntainers Manufacturing Equipment Mechanical hand shears, blade shear machine r straight bench-munted shears t cut aluminium sheets fllwing a template prvided by COET/UDSM Grve rller (als knwn as bead frming rller r curling rller) with mandrels t create reinfrcing grves, hinges

7 (fr the sharps cntainer) and curls n aluminium sheets Hand grver tl t create water-tight duble seams Mallet t frm aluminium sheet and create rivets Hand punches and taps t make hles in the lids Hammer, pliers and ther tls t make simple latches and plug assembly Piercing tl/die fr making hles fr rivets Manufacturing Skills Metal cutting and metal frming prcesses (Cutting, punching and bending f aluminium sheets) including: Bending metal t frm the plug assembly in the lid Frming grves, hinges and curls using a grve rller Making water-tight duble seams Making riveted jints Making latches Applying silicne t seams and lids Making silicne plugs (mld t be prvided by COET/UDSM) Making smth tp rims with wires