This production unit in Northern Ireland was monitored by the author for the purpose of a valuation and viability, commercially. The process is set out as follows The Skim Milk was evaporated with a ' falling film'evaporator to a concentration of 45-46 per cent total solids. The falling film concept made it possible to operate with low temperature differentials and to achieve high thermal efficiency Manual supervision of the equipment was minimal, and the start-up, shut-down and C I.P. could be automatically performed. The evaporator serving the first of two spray dryers was a 4-effect unit, with a three stage instantizer, following the second spray dryer. Initial pasteurization time before evaporation was at 71C for 15 seconds This No l plant handled 19, 350kg of skim milk(at 8 per cent total solids) per hour yielding 1,820kg of powder at 4 per cent moisture per hour The maximum inlet temperature of the drying air was 93C with an outlet at 82C At these temperatures the evaporation was approximately 1, 865kg per hour and the yield of powder at 4 per cent was 1, 820kg per hour -a conversion ratio of10631 The No 2 plant was smaller with a two stage instantizer. The efficiency of the dryer was similar to the No 1 plant with an input of 7, 727kg per hour and a yield of 650kg per hour, although the evaporator was slightly less efficient in that it consumed rather more steam per kg of water evaporated Steam consumption was 1, 600kg per hour for the dryer and 1, 900kg per hour for the evaporator Installed power was 95KVa Packaging was in polyethylene-lined multi-ply paper sacks. Bulk stor age silos had a capacity of 70 tonnes, and the warehouse had a capacity for 2, 000 tonnes of product. he storage of raw milk as previously indicated only provided for 28 hours reserve, and comprised 4 stainless tanks -2 of 114,000 litres capacity and 2 of 91,000 litres, and this feed stock was maintained at 5'C HYGIENE Clean down procedures were carried out daily on the evaporating plant 4 hours wash-down after 20 hours running The spray dryers were cleaned down as necessary at least every 4 weeks QUALITY CONTR。L ests on raw milk include: acidity, total solids, water adulteration, temperature and full bacteriological tests In-process tests include total solids in the concentrateThis production unit in Northern Ireland was monitored by the author for the purpose of a valuation and viability, commercially. The process is set out as follows: The Skim Milk was evaporated with a 'falling film' evaporator to a concentration of 45-46 per cent total solids. The falling film concept made it possible to operate with low temperature differentials and to achieve high thermal efficiency. Manual supervision of the equipment was minimal, and the start-up, shut-down and C.I.P. could be automatically performed. The evaporator serving the first of two spray dryers was a 4-effect unit, with a three stage instantizer, following the second spray dryer. Initial pasteurization time before evaporation was at 71°C for 15 seconds. This No 1 plant handled 19,350kg of skim milk (at 8 per cent total solids) per hour yielding 1,820kg of powder at 4 per cent moisture per hour The maximum inlet temperature of the drying air was 93°C with an outlet at 82°C. At these temperatures the evaporation was approximately 1,865kg per hour and the yield of powder at 4 per cent was 1,820kg per hour - a conversion ratio of 10.63:l. The steam consumption was 3,950kg per hour for the dryer and for the evaporator 3,045kg per hour. Installed power was 240KVa. The No 2 plant was smaller with a two stage instantizer. The efficiency of the dryer was similar to the No 1 plant with an input of 7,727kg per hour and a yield of 650kg per hour, although the evaporator was slightly less efficient in that it consumed rather more steam per kg of water evaporated. Steam consumption was 1,600kg per hour for the dryer and 1,900kg per hour for the evaporator. Installed power was 95KVa. Packaging was in polyethylene-lined multi-ply paper sacks. Bulk stor￾age silos had a capacity of 70 tonnes, and the warehouse had a capacity for 2,000 tonnes of product. The storage of raw milk as previously indicated only provided for 28 hours reserve, and comprised 4 stainless tanks - 2 of 114,000 litres capacity and 2 of 91,000 litres, and this feed stock was maintained at 5°C. HYGIENE Clean down procedures were carried out daily on the evaporating plant; 4 hours wash-down after 20 hours running. The spray dryers were cleaned down as necessary at least every 4 weeks. QUALITY CONTROL Tests on raw milk include: acidity, total solids, water adulteration, temperature and full bacteriological tests. In-process tests include total solids in the concentrate. 204