浮选中间室中粗砂孔的应用

目前,国内大部分中小型浮选厂的浮选中间室仍使用传统的丝杆螺旋装置调节矿浆液面,这种传统的闸门存在如下问题:一是调节各浮选作业矿浆液面的升降速度慢,不能使浮选槽中的矿浆液面降得太低,二是在使用过程中易出现调过了头而脱扣和锈死旋不动等现象。对浮选过程中出现的跑槽、跑水、沉槽、后串等现象不能及时调整,影响浮选指标的提高。因此,黄沙坪铅锌矿选矿厂对其进行了改进,即对原6A、5A浮选机的中间室全部设置粗砂孔。

一种新型负压气浮装置的研究

阐述了气水混合室式气浮装置的工作机理。在实验室条件下确定了试验模型的处理效率 ,试验模型对石油类物质和固体悬浮物 (SS)的去除率达到 95 %以上。并对试验数据进行了分析 ,讨论了气水混合室式气浮装置的去除率与转速的关系 ,达到最佳转速之前去除率随转速的增加而增加 ,达到最佳转速之后去除率随转速的增加而降低。同时得到了估算最佳转速的经验公式。

浅水域围油栏

英国伦敦Skimmex公司推出了一种海岸线围油栏的新产品,专门用以控制较浅的潮水水城溢油污染。 这种围油栏最早用于GC勘探公司和BP石油发展公司在浦耳港西南方向水域合作钻探的一口勘探井,共使用了366米。

新型围油栏

英国维克玛(Vikoma)国际公司推出了一种新型围油栏。它的施放速度比通常使用的围油栏快4倍。 处理溢油事故,围油栏的施放速度极其重要。维苛玛的新型围油栏称为Hi-Sprint(更完善的快速围油栏)。

Nano-microbubble flotation of fine and ultrafine chalcopyrite particles

As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to improve flotation performance of fine and ultrafine particles, there is still much more to be done. In this paper, the effects of nano-microbubbles （nanobuhbles and microbubbles） on the flotation of fine （-38 ＋ 14.36 μm） and ultrafine （-14.36 ＋ 5μm） chalcopyrite particles were investigated in a laboratory scale Denver flotation cell. Nano-microbubbles were generated using a specially-designed nano- microbubble generator based on the cavitation phenomenon in Venturi tubes. In order to better under- stand the mechanisms of nano-microbubble enhanced froth flotation of fine and ultrafine chalcopyrite particles, the nano-microbubble size distribution, stability and the effect of frother concentration on nano- bubble size were also studied by a laser diffraction method. Comparative flotation tests were performed in the presence and absence of nano-microbubbles to evaluate their impact on the fine and ultrafine chalcopyrite particle flotation recovery. According to the results, the mean size of nano-microbubbles increased over time, and decreased with increase of frother concentration. The laboratory-scale flotation test results indicated that flotation recovery of chalcopyrite fine and ultrafine particles increased by approximately 16-21% in the presence of nano-microbubbles, depending on operating conditions of the process. The presence of nano-microbubbles increased the recovery of ultrafine particles （-14.36 ＋ 5 μm） more than that of fine particles （-38 ＋ 14.36 μm）. Another major advantage is that the use of nano-microbubbles reduced the collector and frother consumptions by up to 75% and 50%, respectively.

Effect of galvanic contact on the flotability of galena in the presence and absence of a collector

In this paper,the effect of various electrochemical environments in the galena flotation is investigated.The electrochemical environments consisted of a ball mill for grinding of galena ore and a Denver flotation cell for flotation of galena in the laboratory scale.In order to achieve the maximum recovery with sodium hyposulfite,the concentrations of 0.06 and 0.12 M of air and nitrogen gases have been used to control the pulp potential in the Denver flotation cell.The galena sample was from the ''Era mine'' which is located in the Kiyasar area,north of Iran.This mine contains:Galena(PbS) at least 22%,Fluorite(CaF 2) 73.37%,Quartz(SiO 2) 2.54% and other minerals such as Cerussite(PbCO 3) and Kaolinite(Al 2 Si 2 O 5(OH) 4).Flotation of Galena was conducted in a 0.12 M of sodium hyposulfite solution.It was found that the amount of recovery by this process was 85% and 63% in the presence and absence of potassium amyl xanthate(KAX) and at an estimated potential of 280 to 350 mV respectively while the recovery was 70% and 52% at an approximate potential of 175 to 210 mV in water in the presence and absence of collector(KAX).

Nanobubble generation and its applications in froth flotation(partⅢ):specially designed laboratory scale column flotation of phosphate

Froth flotation is used widely for upgrading raw phosphate.The flotation recovery of coarse phosphate(-1.18+0.425 mm) is much lower than that achieved on the-0.425+0.15 mm size fraction.Enhanced recovery of coarse phosphate particles is of great economic and environmental importance for phosphate industry.In this investigation,four different phosphate samples were aquired,characterized and tested in a specially designed laboratory-scale flotation column.Significant recovery improvement of coarse phosphate flotation was achieved using cavitation-generated nanobubble though its effects differ among the four testing phosphate samples.The laboratory-scale flotation column test results indicate that nanobubble increased P_2O_5 recovery by up to 10%～30%for a given Acid Insoluble(A.I.) rejection,depending on the characteristic of phosphate samples.The improvement effect of nanobubble on the hard-to-float particles was more significant than that on easy-to-float particles,especially at lower collector dosages.Nanobubbles reduced the collector dosage by 1/3 to 1/2.Nanobubbles almost doubled the coarse phosphate flotation rate constant and increased the flotation selectivity index by up to 25%.

Fluorometric Discrimination Technique of Phytoplankton Population Based on Wavelet Analysis

The discrete excitation-emission-matrix fluorescence spectra (EEMS) at 12 excitation wavelengths (400, 430, 450, 460, 470, 490, 500, 510, 525, 550, 570, and 590 nm) and emission wavelengths ranging from 600-750 nm were determined for 43 phytoplankton species. A two-rank fluorescence spectra database was established by wavelet analysis and a fluorometric discrimination technique for determining phytoplankton population was developed. For laboratory simulatively mixed samples, the samples mixed from 43 algal species (the algae of one division accounted for 25%, 50%, 75%, 85%, and 100% of the gross biomass, respectively), the average discrimination rates at the level of division were 65.0%, 87.5%, 98.6%, 99.0%, and 99.1%, with average relative contents of 18.9%, 44.5%, 68.9%, 73.4%, and 82.9%, respectively; the samples mixed from 32 red tide algal species (the dominant species accounted for 60%, 70%, 80%, 90%, and 100% of the gross biomass, respectively), the average correct discrimination rates of the dominant species at the level of genus were 63.3%, 74.2%, 78.8%, 83.4%, and 79.4%, respectively. For the 81 laboratory mixed samples with the dominant species accounting for 75% of the gross biomass (chlorophyll), the discrimination rates of the dominant species were 95.1% and 72.8% at the level of division and genus, respectively. For the 12 samples collected from the mesocosm experiment in Maidao Bay of Qingdao in August 2007, the dominant species of the 11 samples were recognized at the division level and the dominant species of four of the five samples in which the dominant species accounted for more than 80% of the gross biomass were discriminated at the genus level; for the 12 samples obtained from Jiaozhou Bay in August 2007, the dominant species of all the 12 samples were recognized at the division level. The technique can be directly applied to fluorescence spectrophotometers and to the developing of an in situ algae fluorescence auto-analyzer for phytoplankton population.

Laboratory study on the ecological impact of sophorolipid used for harmful algae elimination

We studied the role of sophorolipid in inhibiting harmful algae bloom （HAB）. Different sophorolipid concentrations were tested on marine microalgae, zooplankton, fish, and bivalve （Mytilus edulis） in laboratory. The result shows that sophorolipid could inhibit the growth of algal species selectively. Among three algae species selected, Platymonas helgolandica var. tsingtaoensis was promoted with increasing sophorolipid concentration; Isochrysis galbana was inhibited seven days later in sophorolipid concentration below 40 mg/L; and Nitzschia closterium f. minutissima was inhibited obviously in only a high sophorolipid concentration over 20 mg/L. Therefore, sophorolipid in a low concentration at 〈20 mg/L could remove certain harmful algae species effectivelywithout harming other non-harmful microalgae. For other animals, sophorolipid could inhibit the growth of ciliate Strombidium sp. by 50% at 20 mg/L sophorolipid concentration after 96 h. The concentration in 96-h LC50 for Calanus sinicus, Neomysis awatschensis, Lateolabrax japonicus, and Paralichthys olivaceus was 15, 150, 60, and 110 mg/L, respectively. The 24 h LC50 value for Arternia salina was 600 mg/L. The relative clearance rate of mussel Mytilus edulis decreased to 80%, 40%, and 20% of the control group after being exposed to 20, 50, and 100 mg/L sophorolipid for 24 h. Therefore, the toxicity for mitigation of harmful algae bloom at previously recommended concentration of 5-20 mg/L sophorolipid is low for most tested organisms in this reaserch.

對京戲小生唱法問題的補充說明

在「我對京戲小生唱法的一些意見」一文中有許多地方我覺得自己說得不够清楚,容易引起誤會,所以想再作一些簡單的補充: 一 吕驥同志說:「在處理聲音上京戲走向分聲部以區別下同的角色的年齡和性格,是此許多其他地方戲有很大進步。我们應接受這一科學原則。」這是非常對的。但我以爲京戲對聲部的區分,還不完全像歌曲那樣區分男聲女聲(男女聲各有其自己的特點),京戲裏只是讓年老的角色用粗些的聲音唱。