农业工程学报
農業工程學報
농업공정학보
2014年
10期
1-9
,共9页
李长友%麦智炜%方壮东%张烨
李長友%麥智煒%方壯東%張燁
리장우%맥지위%방장동%장엽
节能%干燥%系统分析%高湿稻谷
節能%榦燥%繫統分析%高濕稻穀
절능%간조%계통분석%고습도곡
energy conservation%drying%system analysis%high moisture paddy%exergy
为了降低高湿稻谷干燥耗能、提高干燥系统作业效率,基于高湿稻谷干燥特性和干燥传递理论,绘制出了高湿稻谷贮存干燥仓内通风去湿降温过程状态参数变化图,设计出了高湿稻谷贮存干燥仓,能够利用常温自然空气实现高湿稻谷干燥和有效回收干燥系统的烟气余热。应用结果显示,在风量谷物比为149 m3/(h·t)时,每间隔1 h,通风2 h,累计贮藏干燥18 h,可使初始含水率31.3%的稻谷平均含水率降低11.36%,回收烟气废热55.3%。针对南方高温高湿的气候特点,设计出了5HNH-15型稻谷逆流热风干燥机和节能干燥工艺系统。试验结果表明,系统的单位耗热量为2939 kJ/kg,与国标≤7400 kJ/kg相比,最高节能可达60%。该文指出了实现高湿稻谷优质、高效节能干燥,合理的工艺系统设计应以客观能势的利用为主,人为提供主观热能消耗为辅。研究结果为粮食干燥设计指明了高效节能途径,为大型粮食集中干燥工艺系统设计提供了参考。
為瞭降低高濕稻穀榦燥耗能、提高榦燥繫統作業效率,基于高濕稻穀榦燥特性和榦燥傳遞理論,繪製齣瞭高濕稻穀貯存榦燥倉內通風去濕降溫過程狀態參數變化圖,設計齣瞭高濕稻穀貯存榦燥倉,能夠利用常溫自然空氣實現高濕稻穀榦燥和有效迴收榦燥繫統的煙氣餘熱。應用結果顯示,在風量穀物比為149 m3/(h·t)時,每間隔1 h,通風2 h,纍計貯藏榦燥18 h,可使初始含水率31.3%的稻穀平均含水率降低11.36%,迴收煙氣廢熱55.3%。針對南方高溫高濕的氣候特點,設計齣瞭5HNH-15型稻穀逆流熱風榦燥機和節能榦燥工藝繫統。試驗結果錶明,繫統的單位耗熱量為2939 kJ/kg,與國標≤7400 kJ/kg相比,最高節能可達60%。該文指齣瞭實現高濕稻穀優質、高效節能榦燥,閤理的工藝繫統設計應以客觀能勢的利用為主,人為提供主觀熱能消耗為輔。研究結果為糧食榦燥設計指明瞭高效節能途徑,為大型糧食集中榦燥工藝繫統設計提供瞭參攷。
위료강저고습도곡간조모능、제고간조계통작업효솔,기우고습도곡간조특성화간조전체이론,회제출료고습도곡저존간조창내통풍거습강온과정상태삼수변화도,설계출료고습도곡저존간조창,능구이용상온자연공기실현고습도곡간조화유효회수간조계통적연기여열。응용결과현시,재풍량곡물비위149 m3/(h·t)시,매간격1 h,통풍2 h,루계저장간조18 h,가사초시함수솔31.3%적도곡평균함수솔강저11.36%,회수연기폐열55.3%。침대남방고온고습적기후특점,설계출료5HNH-15형도곡역류열풍간조궤화절능간조공예계통。시험결과표명,계통적단위모열량위2939 kJ/kg,여국표≤7400 kJ/kg상비,최고절능가체60%。해문지출료실현고습도곡우질、고효절능간조,합리적공예계통설계응이객관능세적이용위주,인위제공주관열능소모위보。연구결과위양식간조설계지명료고효절능도경,위대형양식집중간조공예계통설계제공료삼고。
Moisture content of paddy in South china is mostly above 22%-28%. The energy consumption of drying process is higher in high temperature and high humidity environment than in other environment. Its main reasons are new theory and technology application, and lack of the reasonable design of drying process system. According to the researches at present, evaporation from grains with high moisture content was little affected by grain features, and moisture binding energy of grains with low moisture content was significantly decreased with increasing temperature. The law of binding energy of high moisture content paddy changed with moisture content was obtained. Energy structure of drying system was revealed based on the drying exergy transferring theory of grain. In order to develop industrial application, reduce the energy consumption in the drying process of high moisture content paddy and improve drying efficiency, based on the drying characteristics and exergy transferring theory of high moisture content paddy, a drying process system of high moisture content paddy was designed which could make full use of the normal temperature natural air, be effective recovery of waste heat of flue gas, and achieve energy-efficient drying of high moisture content paddy. Its process curve of ventilate cooling and dehumidifying was drew out and the principle of design was explained. The energy-saving effect was verified by tests. It was pointed out that the segmented dry process model was one of the important ways to solve the problem of high energy consumption. The results of practical applications in a high moisture paddy drying storage warehouse showed that the average moisture content of 31% (dry basis) of high moisture paddy was decreased to 11.36% and the waste flue gas heat was recycled more than 50%, when the ratio of air flux to grain mass was 149 m3/(h·t), ventilation for 2 hours while intervals of 1 hour, and the accumulative storage dry 18 hours. According to the southern climate characteristics of high temperature and high humidity, type 5HNH-15 paddy countercurrent dryer and energy-saving drying process system were designed. Test showed that the subjective heat in drying system wasting converting into a unit heat consumption of high moisture paddy was 2 939 kJ/kg. Compared with national standard, which was less than 7 400 kJ/kg, the highest energy saving could reach 60%. The results pointed out that, in order to realize high quality, high efficiency, energy-saving in high moisture paddy drying, the reasonable process system design was given priority to objective potential use and subjective thermal energy consumption was complementary. The reliability of the technology solutions were confirmed by theory and experiment. The results of the study pointed out a high efficiency and energy-saving way of design for grain drying, and it provided reference for the large grain drying process system design.